Specific leaf area

Alpine grassland vegetation supports globally important biodiversity and ecosystems that are increasingly threatened by climate warming and other environmental changes. Traitbased approaches can support understanding of vegetation responses to global change drivers and consequences for ecosystem functioning. In six sites along a 1314 m elevational gradient in Puna grasslands in the Peruvian Andes, we collected datasets on vascular plant composition, plant functional traits, biomass, ecosystem fluxes, and climate data over three years. The data were collected in the wet and dry season and from plots with different fire histories. We selected traits associated with plant resource use, growth, and life history strategies (leaf area, leaf dry/wet mass, leaf thickness, specific leaf area, leaf dry matter content, leaf C, N, P content, C and N isotopes). The trait dataset contains 3,665 plant records from 145 taxa, 54,036 trait measurements (increasing the trait data coverage of the regional flora by 420%) covering 14 traits and 121 plant taxa (ca. 40% of which have no previous publicly available trait data) across 33 families.

SUMMARY - In southern Europe, the trend towards low input agriculture gives new incentives to sow forages, legumes in particular, with the aim of improving natural pastures, increase the quality of animal feeding and improve soil fertility. However, growth of forage crops in these areas is seriously limited by the ability of each species to grow during cold winters. Therefore, the objective of this work was to evaluate several annual medics cultivated in Mediterranean zones for cold response. Annual species tested were Medicago polymorpha L., M. truncatula Gaertn, M. rugosa Desr. and M. scutellata (L.) Mill. Twenty day old plants were subjected to two temperature regimes: 20/15ºC or 10/5ºC (d/n) for 40 d. Leaf area, dry matter production, growth parameters and solute content (proline, starch and total soluble sugars) were determined. Results will be discussed in relation to differential response of annual medics to cold conditions.

Growth, net photosynthetic rate (P N ), chlorophyll fluorescence induction kinetics, and stromal fructose-1,6-bisphosphatase (sFBPase) in annual legumes native to the Mediterranean region, two clovers (Trifolium subterraneum L. ssp. oxaloides Nyman cv. Clare and T. michelianum Savi cv. Giorgia) and two Medicago species (M. polymorpha L. cv. Anglona and M. truncatula Gaertn. cv. Paraggio), shifted from 20 to 10 ºC for 1 d or developed at 10 ºC were compared with controls kept at 20 ºC. Cold development produced a larger stimulation of growth in the clover cv. Giorgia and the Medicago cv. Paraggio. Transferring plants to low temperatures affected P N relatively less in clovers than in Medicago plants. Development at 10 ºC relieved the inhibition of photosynthesis in Giorgia and Paraggio, but not in Clare and Anglona, which correlated with increases in the maximum rate of carboxylation by ribulose-1,5-bisphosphate carboxylase/oxygenase, RuBPCO (V cmax ), and the photon-saturated rate of electron transport (J max ). In Medicago, transfer from high to low temperature inhibited photosynthesis in a lesser extent in Anglona than in Paraggio, which showed severe limitations at level of V cmax and J max . Development at 10 ºC in Paraggio produced an efficient photosynthetic cold acclimation, this being associated with a two-fold increase of quantum yield of photosystem 2 electron transport (∆F/F' m ) and with the activity of sFBPase. By contrast, Anglona showed an irreversible inhibition of P N coupled with the reduction of carbon metabolism by impairment of Calvin cycle enzyme activities such as RuBPCO and sFBPase, resulting in a poor cold acclimation of photosynthesis in this cultivar.

Summary Tropical forests are globally important, but it is not clear whether biodiversity enhances carbon storage and sequestration in them. We tested this relationship focusing on components of functional trait biodiversity as predictors. Data are presented for three rain forests in Bolivia, Brazil and Costa Rica. Initial above‐ground biomass and biomass increments of survivors, recruits and survivors + recruits (total) were estimated for trees ≥10 cm d.b.h. in 62 and 21 1.0‐ha plots, respectively. We determined relationships of biomass increments to initial standing biomass (AGBi), biomass‐weighted community mean values (CWM) of eight functional traits and four functional trait variety indices (functional richness, functional evenness, functional diversity and functional dispersion). The forest continuum sampled ranged from ‘slow’ stands dominated by trees with tough tissues and high AGBi, to ‘fast’ stands dominated by trees with soft, nutrient‐rich leaves, lighter woods and lower...

Summary Disturbances are widespread and may affect community assembly, species composition, (functional) diversity and hence ecosystem processes. It remains still unclear to what extent disturbance‐mediated species changes scale‐up to changes in community functional properties, especially for species‐rich tropical forests. A large‐scale field experiment was performed in which the dynamics of 15 000 stems >10 cm in diameter was monitored for 8 years in 44 one‐ha forest plots. Twelve functional effect and response traits were measured for the most dominant tree species. The effects of different intensities of disturbance caused by logging and silvicultural treatments on the species and functional diversity of a Bolivian tropical forest community were evaluated, along with how these changes were driven by underlying demographic processes. Disturbance treatments did not affect species diversity or functional diversity indices based on multiple traits related to primary productivity a...

AimPlant functional groups are widely used in community ecology and earth system modelling to describe trait variation within and across plant communities. However, this approach rests on the assumption that functional groups explain a large proportion of trait variation among species. We test whether four commonly used plant functional groups represent variation in six ecologically important plant traits.LocationTundra biome.Time periodData collected between 1964 and 2016.Major taxa studied295 tundra vascular plant species.MethodsWe compiled a database of six plant traits (plant height, leaf area, specific leaf area, leaf dry matter content, leaf nitrogen, seed mass) for tundra species. We examined the variation in species‐level trait expression explained by four traditional functional groups (evergreen shrubs, deciduous shrubs, graminoids, forbs), and whether variation explained was dependent upon the traits included in analysis. We further compared the explanatory power and speci...

Background and aims -Coastal dunes of southern Spain are an original Mediterranean ecosystem, hotspot of biodiversity, insufficiently studied under the functional ecology. We explore co-variation patterns among leaf traits (size, specific leaf area (SLA), nutrient concentrations (N, P, K…), deciduousness and leaf consistence), and growth form in 78 native coastal dune species. Methods -Three coastal dunes of contrasting climatic conditions were sampled and differentiated between fixed and mobile dunes. Species were classified based on growth form, deciduousness and leaf consistence. Leaf samples were collected following Cornelissen et al. (2003) and soil samples were also analysed by ICP-OES and elemental analysis. Key results -Positive co-variation patterns of SLA and leaf [N], and of leaf [N] and leaf [P], were found in two of three sites. Fixed dunes, with a higher proportion of large shrubs, evergreens, and sclerophyllous species, had lower values of SLA and foliar nutrients, and higher values of [C] than mobile dunes. The topsoil of fixed dunes had less [Ca] than in mobile dunes and this was reflected in foliar concentrations. The Mediterranean-subdesert dunes, had a distinct pattern of trait variation. Conclusion -Mediterranean-subdesert coastal dunes are characterized by lower values of leaf [N] and higher values of leaf [Ca] and [Fe] than in other Mediterranean ecosystems and by a broad correlation among SLA, leaf [N], [P] and [K]. Mediterranean-subdesert dunes showed a predominance of xerophytic malacophyllous strategy, whereas Mediterranean -oceanic dunes are dominated by stress tolerant species. Mobile dunes showed a leaf strategy closer to the observed on Mediterranean -subdesert dunes but with a relevantly higher leaf [Ca].

In the context of climate change, extreme heatwaves are often observed. The consequences of these events led to leaf and grape burning, as observed in June 2019 in the South of France. Previous observations showed that genotypic variability exists in response to these heatwaves. One of the main hypotheses to explain the differences is that genotypes could differentially regulate their leaf temperature. This temperature is closely associated with stomatal conductance and the amount of energy absorbed by the leaves. This amount of energy is known to be a consequence of plant architecture that determines light interception. This study was performed on a set of 33 genotypes that were selected with different leaf-burning sensitivities to high temperatures. Functional (i.e., stomatal conductance, photosynthesis) and architectural traits (internode length, leaf area and leaf elevation angles) were measured to compute their heritabilities and to determine correlations between these traits. ...

Polylepis forests, considered relict ecosystems of great ecological importance in the Andes, face significant threats from degradation and climate change. This study evaluated the influence of microclimate, ground cover, and canopy openness on the natural regeneration of three Polylepis species (P. rodolfo-vasquezii, P. canoi, and P. flavipila) in high Andean Forest relics in the Junín and Lima regions of Peru. To achieve this, permanent plots were established in three representative forest patches: María Moya, Curimarca, and Laraos. At each site, 20 m× 20 m plots were delineated and subdivided into 5 m× 5 m quadrants. Within each plot, a central quadrant was selected where microclimatic variables (temperature and relative humidity), structural characteristics (vegetation and plant cover) and reproduction modes (sexual or asexual) in seedlings and/or saplings were recorded. Preliminary findings suggest that Polylepis regeneration may be shaped by canopy cover, which appears to influence the microclimatic conditions of the understory. Soil temperature also seems to play a meaningful role, varying according to the reproductive strategy of each species studied. Interestingly, the presence of lichens and bryophytes showed a potential inverse relationship with sexual regeneration, while more open canopies tended to support greater height in regenerating individuals. Taken together, these patterns point to a possible interplay between microclimate, ground cover, and canopy structure as key factors driving the natural regeneration dynamics of Polylepis ecosystems. These findings underscore the importance of understanding these dynamics to develop conservation strategies that maintain a balance between tree cover and understory functionality in high-Andean ecosystems.

AimPlant functional groups are widely used in community ecology and earth system modelling to describe trait variation within and across plant communities. However, this approach rests on the assumption that functional groups explain a large proportion of trait variation among species. We test whether four commonly used plant functional groups represent variation in six ecologically important plant traits.LocationTundra biome.Time periodData collected between 1964 and 2016.Major taxa studied295 tundra vascular plant species.MethodsWe compiled a database of six plant traits (plant height, leaf area, specific leaf area, leaf dry matter content, leaf nitrogen, seed mass) for tundra species. We examined the variation in species‐level trait expression explained by four traditional functional groups (evergreen shrubs, deciduous shrubs, graminoids, forbs), and whether variation explained was dependent upon the traits included in analysis. We further compared the explanatory power and speci...

The objective of this work was to investigate the effects of shading on the growth and development of the medicinal plant Ocimum selloi after 90 days. Seedlings were maintained under three different light treatments, namely, full sunlight vs coloured shade treatments provided by red and blue ChromatiNet® 50% coloured netting. After 90 days of cultivation, height, stem diameter, petiole length, total leaf area (TLA), specific leaf area (SLA), leaf area ratio (LAR) and leaf weight ratio (LWR) of each plant hare measured. Microscopic examination of leaf sections were conducted in order to determine the leaf blade thicknesses, together with the size and density of the stomata, the number and area of chloroplasts, and chloroplast starch grains present in the palisade parenchyma cells. Although coloured shade-grown plants were taller in comparison with those grown in full sunlight, total dry biomass together with root, stem and leaf tissue biomasses were lower. Plants exhibited phenotypic...

In this study, we investigate seedlings of Quercus castaneifolia C.A. Mey, from five different provenances for the research on leaf and crown morphological variations in relation to a light gradient under controlled conditions in a greenhouse. The results show that significant variations occurred in many parameters due to the effects of light availability. The seedling responses to low light include the proportional allocation of more biomass to leaves, leading to higher leaf mass, leaf area, crown area, specific leaf area and leaf area ratio, in contrast, the seedlings grown in high irradiance faced a high temperature resulting in higher transpiration. At this period, seedlings alter their leaf and crown size to prevent overheating. In this experiment, in spite of the same treatments in controlled conditions in a greenhouse, the seedlings from different provenances indicate different responses to light levels. It seems that the seedlings try to maximize their surface area for the i...

Raising quality hybrid potato true seedlings -derived from hybrid true potato seeds (TPS) -for field transplanting is a critical aspect contributing to the success in cultivating field-transplanted hybrid potato seedling-based crops. Various critical seedling vigour attributes must be defined and enhanced to improve plant performance as well as plant response and adaptation to field conditions after field transplanting. Moreover, additional attributes besides leaf number and stem length should be defined to design selection criteria for "transplantability" of potato seedlings. To assess these attributes and their robustness under different environmental conditions, seedlings of hybrid genotypes were raised under contrasting daylengths, light intensities and temperature regimes, and combinations of these factors, and the effects of these factors (or factor combinations) on seedling vigour and its attributes were quantified. Increased light intensity and daylight integral (DLI) enhanced leaf parameters and increased biomass under long-day conditions, but seedlings did not show conclusive responses under short-day conditions in most attributes. Higher temperatures increased biomass and constant day and night temperatures enhanced compaction of shoot architecture as did higher light intensities -to a greater extent. These results highlight additional seedling vigour attributes including leaf area parameters and seedling biomass which should be utilised to determine "transplantability" of hybrid potato seedlings. Additionally, the results provide a starting point for further research on optimising hybrid seedling production for field transplanting.

To cite this paper: Sarwar, MA, F. Hussain, A. Ghaffar, MA Nadeem, MM Ahmad, M. Bilal, AA Chattha and M. Sarwar, 2008. Post-harvest studies in sugarbeet (Beta vulgaris). J. Agri. Soc. Sci., 4: 89–91 ... Post-Harvest Studies in Sugarbeet (Beta vulgaris)

IntroductionPlant functional traits (FTs) are important for understanding plant ecological strategies (e.g., drought avoidance), especially in the nutrient-poor soils of serpentine ecosystems. In the Mediterranean areas, such ecosystems are characterized by climatic factors (e.g., summer drought) that exert a filtering effect.Material and MethodsIn our study, we analyzed 24 species with varying serpentine affinity, from strictly serpentine plants to generalist plants, from two ultramafic shrublands in southern Spain, considering four FTs: plant height (H), leaf area (LA), specific leaf area (SLA), and stem specific density (SSD). Additionally, we also identified the species’ dominant strategies to avoid drought and those strategies’ relationship to serpentine affinity. We used principal component analysis to identify combinations of FTs, and cluster analysis to define Functional Groups (FGs).Results and DiscussionWe defined eight FGs, which suggests that such Mediterranean serpentin...

Climate change and global warming have worldwide adverse consequences. Biochar production and its use in agriculture can play a key role in climate change mitigation and help improve the quality and management of waste materials coming from agriculture and forestry. Biochar is a carbonaceous material obtained from thermal decomposition of residual biomass at relatively low temperature and under oxygen limited conditions (pyrolysis). Biochar is currently a subject of active research worldwide because it can constitute a viable option for sustainable agriculture due to its potential as a long-term sink for carbon in soil and benefits for crops. However, to date, the results of research studies on biochar effects on crop production show great variability, depending on the biochar type and experimental conditions. Therefore, it is important to identify the beneficial aspects of biochar addition to soil on crop yield in order to promote the adoption of this practice in agriculture. In this study, the effects of two types of biochar from agricultural wastes typical of Southern Spain: wheat straw and olive tree pruning, combined with different mineral fertilization levels on the growth and yield of wheat (Triticum durum L. cv. Vitron) were evaluated. Durum wheat was pot-grown for 2 months in a growth chamber on a soil collected from an agricultural field near Córdoba, Southern Spain. Soil properties and plant growth variables were studied in order to assess the agronomic efficiency of biochar. Our results show that biochar addition to a nutrientpoor, slightly acidic loamy sand soil had little effect on wheat yield in the absence of mineral fertilization. However, at the highest mineral fertilizer rate, addition of biochar led to about 20-30 % increase in grain yield compared with the use of the mineral fertilizer alone. Both biochars acted as a source of available P, which led to beneficial effects on crop production. In contrast, the addition of biochar resulted in decreases in available N and Mn. A maximum reduction in plant nutrient concentration of 25 and 80 % compared to nonbiochar-treated soils for N and Mn, respectively, was detected. This fact was related to the own nature of biochar: low available nitrogen content, high adsorption capacity, and low mineralization rate for N; and alkaline pH and high carbonate content for Mn. Our results indicate that biochar-based soil management strategies can enhance wheat production with the environmental benefits of global warming mitigation. This can contribute positively to the viability and benefits of agricultural production systems. However, the nutrient-biochar interactions should receive special attention due to the great variability in the properties of biochar-type materials.

, 'Golden Delicious' apples from controlledatmosphere (CA) storage (1% O 2 ; 3% CO 2 ) averaged 8.5 N firmer after 30 days and 13.5 N firmer after 60 days of storage than apples from regular-atmosphere (RA) storage. After 7 days of ambient storage, 'Golden Delicious' apples from CA storage were 10.3 N firmer than apples from RA storage. Little change in color was evident in 'Golden Delicious' apples from CA storage after 30 or 60 days, but a distinct increase in yellow color was evident in apples from RA storage after only 30 days. The quality (color, firmness, and acidity) of 'Golden Delicious' apples stored for 30 days under CA and then 30 days under RA was superior to that of 'Golden Delicious' apples after 60 days of RA storage and similar to that of 'Golden Delicious' apples after 60 days of CA storage. 'Granny Smith' apples, traditionally a very firm apple regardless of the type of storage, averaged 3.3 N firmer after 30 days of CA storage (1% O 2 ; 1% CO 2 ) and 5.8 N firmer after 60 days of CA storage when compared to apples from RA storage. Little change in color was evident in 'Golden Delicious' apples regardless of storage length, but under ambient storage temperatures, 'Golden Delicious' apples from CA storage maintained their green color longer. Titratable acidity of both 'Golden Delicious' and 'Granny Smith' apples depended on growing season, and neither 'Golden Delicious' nor 'Granny Smith' apples showed consistent trends in titratable acidity after either RA or CA storage.

Leaf traits characterise and differentiate single species but can also be used for monitoring vegetation structure and function. Conventional methods to measure leaf traits, especially at the molecular level (e.g. water, lignin and cellulose content), are expensive and time-consuming. Spectroscopic methods to estimate leaf traits can provide an alternative approach. In this study, we investigated high spectral resolution (6612 bands) emissivity measurements from the short to the long wave infrared (1.4-16.0 μm) of leaves from 19 different plant species ranging from herbaceous to woody, and from temperate to tropical types. At the same time, we measured 14 leaf traits to characterise a leaf, including chemical (e.g., leaf water content, nitrogen, cellulose) and physical features (e.g., leaf area and leaf thickness). We fitted partial least squares regression (PLSR) models across the SWIR, MWIR and LWIR for each leaf trait. Then, reduced models (PLSR red ) were derived by iteratively reducing the number of bands in the model (using a modified Jackknife resampling method with a Martens and Martens uncertainty test) down to a few bands (4-10 bands) that contribute the most to the variation of the trait. Most leaf traits could be determined from infrared data with a moderate accuracy (65 < R cv 2 < 77% for observed versus predicted plots) based on PLSR red models, while the accuracy using the whole infrared range (6612 bands) presented higher accuracies, 74 < R cv 2 < 90%. Using the full SWIR range (1.4-2.5 μm) shows similarly high accuracies compared to the whole infrared. Leaf thickness, leaf water content, cellulose, lignin and stomata density are the traits that could be estimated most accurately from infrared data (with R cv 2 above 0.80 for the full range models). Leaf thickness, cellulose and lignin were predicted with reasonable accuracy from a combination of single infrared bands. Nevertheless, for all leaf traits, a combination of a few bands yields moderate to accurate estimations.

Water extraction from the underground aquifers of the Pampa del Tamarugal (Atacama Desert, Chile) reduced the growing area of , a strict phreatic species endemic to northern Chile. The objective of this work was to evaluate the effect of various architectural and morpho-physiological traits adjustment of subjected to three groundwater depletion intervals (GWDr): &lt;1 m (control), 1-4 m and 6-9 m. The traits were evaluated at three levels, plant [height, trunk cross-section area, leaf fraction (GCC), and crown size], organ [length of internodes, leaf mass per unit area (LMA), leaflet mass and area], and tissue level [wood density (WD), leaf C, O isotope composition (δ), and intrinsic water use efficiency (iWUE)]. In addition, soil water content (VWC) to 1.3 m soil depth, pre-dawn and midday water potential difference (ΔΨ), and stomatal conductance (g) were evaluated. At the deeper GWDr, experienced significant growth restriction and reduced GCC, the remaining canopy had a significan...

Alpine grassland vegetation supports globally important biodiversity and ecosystems that are increasingly threatened by climate warming and other environmental changes. Traitbased approaches can support understanding of vegetation responses to global change drivers and consequences for ecosystem functioning. In six sites along a 1314 m elevational gradient in Puna grasslands in the Peruvian Andes, we collected datasets on vascular plant composition, plant functional traits, biomass, ecosystem fluxes, and climate data over three years. The data were collected in the wet and dry season and from plots with different fire histories. We selected traits associated with plant resource use, growth, and life history strategies (leaf area, leaf dry/wet mass, leaf thickness, specific leaf area, leaf dry matter content, leaf C, N, P content, C and N isotopes). The trait dataset contains 3,665 plant records from 145 taxa, 54,036 trait measurements (increasing the trait data coverage of the regional flora by 420%) covering 14 traits and 121 plant taxa (ca. 40% of which have no previous publicly available trait data) across 33 families.

Nutrient resorption is one of the most important nutrient use strategies developed by plants. The ratio of leaf area to dry mass (SLA) is related to leaf nutrients. In this study, the changes in SLA, N, P concentrations, N/ P ratio and C content of sun and shade leaves of the evergreen liana Hedera helix L. were investigated over the year in an altitudinal gradient. Foliar resorption efficiency (RE) and proficiency (RP) were also calculated in sun and shade leaves. Leaf traits significantly changed among studied localities and over the year. There were statistically significant differences between sun and shade leaves regarding SLA, N concentration and C content, but these were dependent on the differences of altitude. However, no significant differences were found for P concentrations between sun and shade leaves. SLA increased in sun and shade leaves at the end of the spring and decreased after the fall. Leaf C content generally increased in January. Leaf N concentration in sun an...

Intraspecific trait variation has been singled out as an important mechanism by which individuals can cope with environmental variations and avoid local extinctions. Here we evaluate variation in metamer traits (i.e., traits associated with internodes, petioles and their corresponding leaves) and parameters of chlorophyll fluorescence within and among populations of a neotropical tree, Copaifera langsdorffii. We also evaluated phenotypic plasticity in natural settings comparing traits between shade and sun-exposed metamers. We selected six populations along a climatic gradient ranging from semi-arid to humid and representing three different biomes (Caatinga, Cerrado, and Atlantic Forest). Local climatic conditions significantly affected the morphological and physiological traits of populations. Trait variation among populations was explained mainly by aridity index and evapotranspiration. Individuals from drier regions had lower specific leaf area (SLA), lower investment in leaf area per total dry mass of metamer (LARm), lower specific petiole length (SPL) and lower potential quantum yield (Fv/Fm, only for sun-exposed metamers). Populations from locations with greater environmental heterogeneity (interannual variation) had greater plasticity in response to light for Fv/Fm and electron transport rate (ETR) and morphological traits related to the hydraulic and biomechanical aspects of the leaves (petiole length, internode length and SPL). High intraspecific variation in metamer traits in C. langsdorffii coupled with its ability to modify these traits in response to different climate conditions can explain the success of the species over a range of different habitats and represent important factors for the persistence of this species in the face of climate change.

Plant functional types (PFTs) have been widely proposed as an ecological alternative to classical taxonomy and include easily measurable traits such as life form, leaf habit, plant height, plant longevity, and specific leaf area (SLA). They exhibit similar responses to environmental conditions and also have similar effects on matter and energy processes in ecosystems . PFTs consist of species that have common morphological and physiological attributes, and classification schemes according to PFTs can include the identification of correlations among quantitative traits that reflect life history trade-off or assignment of species to plant functional groups based on dominant traits (Garcia-

Proleptic flowering is common among plant species from tropical seasonal forests. In these species flower initiation and anthesis are separated by a prolonged rest period (the unfavorable season), and the two processes are controlled separately. Proleptic species are appropriate for assessing the withinand between-season effects of herbivory on flowering and reproductive success. We investigated the reproductive consequences of artificial defoliation of the proleptic shrub Erythroxylum havanense, in a seasonal dry forest in western Mexico. Twenty individuals in each of three sites were randomly assigned to one of four treatments: control (no manipulation), and three levels of leaf area removed: 0, 25, and 100%. Plants in the latter three treatments were sprayed with insecticide to prevent additional foliage consumption by natural herbivores. Within a season undamaged plants (control and 0% defoliation) produced from two to four times more seeds than damaged ones (25 and 100% defoliation). In addition, completely defoliated plants exhibited a significant increase in both fruit maturation time (8 d) and average seed mass (9.5%), when compared to the plants in the other treatments. There was no evidence of a trade-off between seed number and seed mass, or between ripening time and seed mass. One year after defoliation, vegetative growth (basal area increment) was reduced only by 100% defoliation. Likewise, flower and fruit production were significantly reduced only in this treatment. Although defoliation reduced seed production in both years, only the first year's reduction was a direct consequence of defoliation. Seed production decline in year 2 was an indirect effect of the reduction in flower number, suggesting that fruit and seed maturation do not depend on resources stored, but on annual production of photosynthates. Plant survival was not affected up to 5 yr after defoliation. Since most of the effects were evident only in the 100% defoliated plants, our results reflect those instances when insect outbreaks occur and E. havanense plants are completely defoliated.

To cite this paper: Sarwar, MA, F. Hussain, A. Ghaffar, MA Nadeem, MM Ahmad, M. Bilal, AA Chattha and M. Sarwar, 2008. Post-harvest studies in sugarbeet (Beta vulgaris). J. Agri. Soc. Sci., 4: 89–91 ... Post-Harvest Studies in Sugarbeet (Beta vulgaris)

Alpine grassland vegetation supports globally important biodiversity and ecosystems that are increasingly threatened by climate warming and other environmental changes. Traitbased approaches can support understanding of vegetation responses to global change drivers and consequences for ecosystem functioning. In six sites along a 1314 m elevational gradient in Puna grasslands in the Peruvian Andes, we collected datasets on vascular plant composition, plant functional traits, biomass, ecosystem fluxes, and climate data over three years. The data were collected in the wet and dry season and from plots with different fire histories. We selected traits associated with plant resource use, growth, and life history strategies (leaf area, leaf dry/wet mass, leaf thickness, specific leaf area, leaf dry matter content, leaf C, N, P content, C and N isotopes). The trait dataset contains 3,665 plant records from 145 taxa, 54,036 trait measurements (increasing the trait data coverage of the regional flora by 420%) covering 14 traits and 121 plant taxa (ca. 40% of which have no previous publicly available trait data) across 33 families.

To cite this paper: Sarwar, MA, F. Hussain, A. Ghaffar, MA Nadeem, MM Ahmad, M. Bilal, AA Chattha and M. Sarwar, 2008. Post-harvest studies in sugarbeet (Beta vulgaris). J. Agri. Soc. Sci., 4: 89–91 ... Post-Harvest Studies in Sugarbeet (Beta vulgaris)

Seedling vigor, defi ned here as total seedling biomass, is directly related to seedling performance in the face of environmental harshness. Additionally, diff erential portioning between shoot and root biomass can be a determinant of seedling survival under conditions of resource scarcity. We aimed to determine the biomass allocation pattern of Euterpe edulis seedlings and test the hypothesis that heavier seeds produce more vigorous seedlings. We followed a germination protocol that produced 50 seedlings, 32 of which were used to calculate the total seedling biomass investment, relative growth rate (RGR), specifi c leaf area (SLA), and root/shoot ratio (R/S). A linear regression showed that the root/shoot ratio (R/S) increased with increasing seed mass (p = 0.03). This result may be a consequence of diff ering seed reserves accumulated by seeds of diff erent masses. Seed mass was also directly related to seedling vigor (p = 0.03). Despite the lack of relationship between seed mass and RGR (p = 0.553), the positive relationship between seed mass and SLA (p = 0.03) suggests that heavier seeds have a slow-growth strategy, whereas lighter seeds have a fastgrowth strategy. As heavier seeds produce more vigorous seedlings, they should be preferred when planning restoration plantations since their seedlings have greater chances of survival under harsh conditions and may present more satisfactory performance. Additionally, since the population studied is already located at the upper thermal limit of the species, we suggest that future studies focus on how seedlings of diff erent sizes perform at diff erent temperatures.

Due to the role leaf phenolics in defending against ultraviolet B (UVB) under previously controlled conditions, we hypothesize that ultraviolet radiation (UVR) could be a primary factor driving the variation in leaf phenolics in plants over a large geographic scale. We measured leaf total phenolics, ultraviolet-absorbing compounds (UVAC), and corresponding leaf N, P, and specific leaf area (SLA) in 151 common species. These species were from 84 sites across the Tibetan Plateau and Inner Mongolian grasslands of China with contrasting UVR (354 vs. 161 mW/cm 2 on average). Overall, leaf phenolics and UVAC were all significantly higher on the Tibetan Plateau than in the Inner Mongolian grasslands, independent of phylogenetic relationships between species. Regression analyses showed that the variation in leaf phenolics was strongly affected by climatic factors, particularly UVR, and soil attributes across all sites. Structural equation modeling (SEM) identified the primary role of UVR in determining leaf phenolic concentrations, after accounting for colinearities with altitude, climatic, and edaphic factors. In addition, phenolics correlated positively with UVAC and SLA, and negatively with leaf N and N: P. These relationships were steeper in the lower-elevation Inner Mongolian than on the Tibetan Plateau grasslands. Our data support that the variation in leaf phenolics is controlled mainly by UV radiation, implying high leaf phenolics facilitates the adaptation of plants to strong irradiation via its UV-screening and/or antioxidation functions, particularly on the Tibetan Plateau. Importantly, our results also suggest that leaf phenolics may influence on vegetation attributes and indirectly affect ecosystem processes by covarying with leaf functional traits.

A kutatás fő témái az időjárás - ezen belül kiemelten a hőmérséklet - rizsre gyakorolt hatásának vizsgálata és a hőmérsékleti viszonyok elemzése (különböző idő- és térskálák). Új/újszerű eredmények a következő területeken születtek: fenológiai fejlődés leírása, hőösszeg-modell (bilineáris), termésbecslés, hidegstressz kockázatelemzése, rizsállomány mikroklímája, árasztóvíz hőmérsékletének modellezése. The effect of weather (especially the temperature) on the development and yield of the rice, and the analysis of thermal conditions (different spatial and time scales) were the main topics of the research. The research resulted in new/newish information in the fields of: modelling of phenological development (bilinear thermal time model), prediction of yield, risk analysis of cold stress, microclimate of rice fields, modelling of floodwater temperature

In this review we analysed inherent differences in Relative Growth Rate (RGR) between herbaceous species or genotypes in terms of variation in the growth parameters Net Assimilation Rate (NAR), Leaf Area Ratio (LAR), Specific Leaf Area (SLA) and Leaf Mass Ratio (LMR). We did so after introducing the 'Growth Response Coefficients' (GRCs), which indicate how a proportional difference in any of the growth parameters scales with the observed proportional difference in RGR. A GRC NAR value of 1 indicates that a given proportional difference in RGR is accompanied by a proportional difference in NAR of the same magnitude; a GRC NAR of 0 indicates that a difference in RGR is not accompanied by any systematic difference in NAR. Averaged over all literature on herbaceous species the GRC NAR was 0.26 and the GRC LAR was 0.74, indicating that LAR is by far the most important factor in explaining inherent variation in RGR. The differences in LAR were mainly due to variation in SLA, GRC SLA being 0.63 and GRC LMR 0.11. We tested in both a direct and an indirect way whether the relative importance of LAR was highest in experiments with low-light grown plants, with variation in NAR being more important in experiments conducted at highlight. In none of the two ways did we find any support for this hypothesis.

Coffee is an important crop in the global south. However, ongoing changes in the climate system reinforce the need to quantify coffee plants' ecological and eco-physiological traits to assure coffee production in the future. One way to assess how environmental changes affect coffee performance is via leaf traits, most notably leaf carbon and nitrogen concentrations (to reflect the nutrient status), leaf stable carbon isotope composition (δ 13 C) to determine intrinsic water use efficiency (WUEi), and specific leaf area (SLA) to describe carbon gain relative to water loss within a plant canopy as these traits are related to yields. Therefore, we sampled coffee plants growing at contrasting elevations using a space-for-time substitution approach for warming and superimposed a canopy cover gradient to assess whether increasing canopy cover could modulate responses to temperature. Three coffee shrubs were sampled in each of 59 coffee farms in southwest Ethiopia across elevations of 1500-2160 m a.s.l. and along canopy cover gradients from open to deep shade. Soil nutrient concentrations, light availability, soil temperature and moisture were quantified for each coffee shrub. Elevation and shade tree canopy cover significantly and interactively affected WUEi. Elevation was found to be the driving factor for microclimate and soil factors which indirectly influenced both SLA and WUEi. Both of these coffee leaf traits are moderately governed by soil temperature whereas leaf N and C:N are mainly controlled by soil temperature and soil chemical variables. As elevation increased, WUEi kept increasing at light (< 35%) to intermediate shade levels (35-65%), and the values decreased at dense shade levels (65-100%) at high elevations, suggesting that coffee plants growing at high elevations with light shade can assimilate more CO 2 with minimum evaporative water loss. SLA declined with elevation. Leaf N and leaf C:N responded negatively and positively to shade canopy cover, respectively. In sum, elevation and canopy cover interactively determined microclimate and coffee leaf traits. Our findings are useful to adjust the intensity of shade, along with other tree-level management tools, to modulate climate-change effects on coffee at the farm level.

Although the potential for increased temperature is the primary and best-studied aspect of anthropogenic climate change, altered rainfall patterns, increased storm intensity, and more severe droughts are also predicted in most climate-change scenarios. We altered experimentally the rainfall regime in a native tallgrass prairie in northeastern Kansas and assessed leaf-level physiological activity and plant growth responses for C 3 and C 4 plant species. Our primary objective was to contrast the importance of reductions in rainfall quantity (30% smaller rain events, no change in rainfall pattern) with an altered, more extreme distribution of rainfall (no reduction in total growing-season quantity, 50% increased inter-rainfall dry intervals) for these dominant species from the two main plant functional groups (C 4 grasses, C 3 forbs) present in many grasslands. Leaf water potential (w l ), net photosynthetic carbon gain ( ), specific leaf mass, leaf C : N ratio, growth rate A CO2 for Andropogon gerardii (C 4 grass) and Solidago canadensis (C 3 forb), vegetative and flowering stem densities, and canopy light penetration for grass and forb assemblages were intensively monitored during the 1999 growing season in a long-term rainfall manipulation study at the Konza Prairie Biological Station. Soil water content at 0-30 cm depth was more variable in response to the altered rainfall distribution compared to the reduced-quantity treatment. In S. canadensis, , g s (stomatal conductance), A : Ci (leaf stomatal [CO 2 ]), A CO2 and A : E (estimated leaf transpiration rate) were positively correlated with soil water content, but no relationship was seen for A. gerardii, indicating that even though this dominant grass species has most of its roots in the upper 30 cm of the soil, A. gerardii was buffered physiologically from increased resource variability. There were few significant responses in growth parameters in either grasses or forbs, but canopy light penetration increased with both rainfall treatments. We concluded (1) that the temporal variability in rainfall inputs can have as much impact on soil moisture as simple reductions in rainfall quantities with no change in temporal distribution, (2) that responses of A. gerardii and S. canadensis to altered rainfall distributions were not consistent with common views of soil resource partitioning between shallow-rooted grasses and deep-rooted forbs, and (3) that altered rainfall patterns may have the potential to offset elevated CO 2 impacts on grassland vegetation.

Introduction: Water availability is one of the main factors determining the distribution of woody species in the tropics. Although the functional mechanisms that determine the species tolerance to water deficit have been extensively studied in adult individuals, the responses of early ontogenetic stages have been less explored. Objective: To identify functional strategies and trait correlations between different seedlings&#39; dimensions (leaf, stem, and root). We expect limited coordination between above and below-ground functional traits due to a single conservation-acquisition trade-off cannot capture the variability of functions and environmental pressures to which the root system is subjected. Methods: We measured 12 functional traits belonging to 38 seedling species in a tropical dry forest in Colombia. We explored the relationships between pairs of traits using Pearson correlations, and to obtain an integrated view of the functional traits, a principal component analysis (PCA...

Heteroblastic plants produce markedly different leaf morphologies between juvenile and adult stages, while homoblastic plants exhibit little or gradual changes. We tested the hypothesis that the leaf morphology of the seedling stage of New Zealand heteroblastic species is advantageous in dealing with low light levels found in forest understorey. We used four independent contrasts of heteroblastic and homoblastic seedlings from

Climate models predict a further drying of the Mediterranean summer. One way for plant species to persist during such climate changes is through acclimation. Here, we determine the extent to which trait plasticity in response to drought differs between species and between sites, and address the question whether there is a trade‐off between drought survival and phenotypic plasticity. Throughout the summer we measured physiological traits (photosynthesis – Amax, stomatal conductance – gs, transpiration – E, leaf water potential – ψl) and structural traits (specific leaf area – SLA, leaf density – LD, leaf dry matter content – LDMC, leaf relative water content – LRWC) of leaves of eight woody species in two sites with slightly different microclimate (north‐ versus south‐facing slopes) in southern Spain. Plant recovery and survival was estimated after the summer drought period. We found high trait variability between species. In most variables, phenotypic plasticity was lower in the dri...

1. Many studies discuss the adaptive value of plant architecture, but few have actually measured architectural effects on plant growth and survival. In this study, sapling growth and survival are related to crown traits for two tree species, Trophis mexicana (Liebm.) Bur. and Pseudolmedia oxyphyllaria Donn. Sm., in the Los Tuxtlas lowland rainforest of Mexico. The traits investigated were crown width, crown depth, number of leaves, number of leaves per unit crown area (horizontal self-shading), and number of leaves per unit silhouette area (vertical self-shading). 2. Self-shading indices decreased with crown size, but were unaffected by the number of leaves per tree. Larger crowns thus had more diffuse foliage, with less self-shading. 3. The number of leaves had positive effects on growth and survival, while self-shading indices had no effect. This indicates that shaded leaves do not necessarily have negative carbon balances. 4. Negative effects of crown width on horizontal crown growth, and positive effects on vertical crown growth, suggest that saplings tend to grow towards a shape intermediate between the narrow and wide crown extremes. 5. Survival was positively correlated with crown width in Pseudolmedia, and with the number of leaves in Trophis. Apparently, dependence of survival on crown traits differed among species. 6. Crown traits affected plant growth and survival, but the hypothesis emerging from light-limited carbon acquisition was confounded by other factors, such as tree size and the inherent branching patterns. 7. Crown traits are good and rather simple predictors of future sapling growth and survival, and may help foresters to select potential crop trees.

Water extraction from the underground aquifers of the Pampa del Tamarugal (Atacama Desert, Chile) reduced the growing area of , a strict phreatic species endemic to northern Chile. The objective of this work was to evaluate the effect of various architectural and morpho-physiological traits adjustment of subjected to three groundwater depletion intervals (GWDr): &lt;1 m (control), 1-4 m and 6-9 m. The traits were evaluated at three levels, plant [height, trunk cross-section area, leaf fraction (GCC), and crown size], organ [length of internodes, leaf mass per unit area (LMA), leaflet mass and area], and tissue level [wood density (WD), leaf C, O isotope composition (δ), and intrinsic water use efficiency (iWUE)]. In addition, soil water content (VWC) to 1.3 m soil depth, pre-dawn and midday water potential difference (ΔΨ), and stomatal conductance (g) were evaluated. At the deeper GWDr, experienced significant growth restriction and reduced GCC, the remaining canopy had a significan...

The water relation strategy of a species (iso-anisohydric continuum as one of the most widely used definitions) is a key issue in the context of climate change. Given the difficulty of determining water relations strategy, there is a need for simple traits with a solid theoretical basis to estimate it. Among the many possibilities, traits associated with the &quot;fast-slow&quot; plant economics spectrum are particularly interesting. Avocado, Fig, Mandarin, Olive, Pomegranate, and Vine were characterized in terms of stomatal behavior, water potential at the turgor loss point (TLP), and Hydroscape Area, and the association of these metrics with leaf mass per area (LMA) and wood density (WDen) was explored. Our results showed high coordination between LMA and WDen across the six species, and both traits were related to metrics of water relation strategy. Species with less regulation of their water status tended to invest a greater amount of carbon per unit leaf area or unit stem volum...

This study assesses the agronomic performance of rice varieties introduced in Morocco using a randomized complete block design (RCBD) with three replications at the irrigated site of Sidi Allal Tazi Experimental Domain. Thirty-three Kafaci rice lines, selected from 100 introduced by the Africa Rice Center in Saint-Louis, Senegal, underwent comprehensive evaluation for agro-morphological parameters and yield potentials. The objective is to evaluate and categorize newly introduced rice varieties in Morocco based on their agronomic performance, employing statistical tools such as hierarchical cluster analysis (HCA) and principal component analysis (PCA) to identify distinct groups suitable for local cultivation. The HCA and PCA classified rice accessions into three classes based on their agronomic performances. Class 1 (KF20005, KF190112, KF20034, KF20059, KF190061) showed relatively lower performance, suggesting potential adaptation to environments requiring less biomass. Class 2 (KF190136, KF190006, KF20058, KF20019, KF190065, KF190022) demonstrated high potential in grain weight and seed production, particularly suited for climates with limited growing seasons. Class 3 (KF20017, KF20018, KF190114, KF20046, KF20006, KF20013), characterized by slower maturation and higher biomass production, is suitable for systems emphasizing biomass utilization. Additionally, PCA identified four quadrants based on similar agronomic characteristics: Top Right Quadrant (KF190063, KF190065, KF18045, KF20006, KF20046) characterized by high yields and resistance; Top Left Quadrant (Lagostino, KF20005, KF190136) with specific traits such as tiller number and sowing-heading cycle; Bottom Left Quadrant (KF20034, KF20059, KF190061) indicating areas needing significant improvement; Bottom Right Quadrant (KF20013, KF20017, KF20018, KF190114) targeted for specific breeding or improvement programs. This research provides insights into future selection and genetic improvement efforts to enhance food security and economic sustainability in the region.

Screening species-rich communities for the variation in functional traits along environmental gradients may help understanding the abiotic drivers of plant performance in a mechanistic way. We investigated tree leaf trait variation along an elevation gradient (1000–3000 m) in highly diverse neotropical montane forests to test the hypothesis that elevational trait change reflects a trend toward more conservative resource use strategies at higher elevations, with interspecific trait variation decreasing and trait integration increasing due to environmental filtering. Analysis of trait variance partitioning across the 52 tree species revealed for most traits a dominant influence of phylogeny, except for SLA, leaf thickness and foliar Ca, where elevation was most influential. The community-level means of SLA, foliar N and Ca, and foliar N/P ratio decreased with elevation, while leaf thickness and toughness increased. The contribution of intraspecific variation was substantial at the com...

The assessment of Visible Foliar Symptoms (VFS) is commonly adopted by forest monitoring programs to evaluate ozone impact on vegetation. The occurrence of ozone VFS may differ among individuals of the same species at the same site, and within leaves of the same individual. The aim of this study was to identify site and plant characteristics as well as functional leaf traits associated with the occurrence and severity of VFS in Viburnum lantana (an ozone-sensitive species) and at the scale of an individual site. V. lantana plants growing at one site of the ViburNeT monitoring network (Trentino, North Italy) experiencing high ozone levels were surveyed in relation to 1) sun exposure, 2) shading effect from neighbor vegetation, 3) plant height and 4) presence and severity of VFS. Leaves from three different sections of each plant were subjected to a phenotypic characterization of leaf area, dry weight, specific leaf area (SLA), chlorophyll content (Chl SPAD ), percentage of VFS, and adaxial and abaxial trichome density (Tr). We showed that plants at high irradiation levels had significantly lower SLA (p<0.05), higher Tr (p<0.01) and greater Chl SPAD (p<0.01) when compared to shaded and/or west-and north-exposed plants, thus indicating a strong influence of sitespecific characteristics on leaf trait plasticity. Similar differences were observed for taller vs. shorter plants and apical vs. basal branches (p<0.05). Ozone-induced VFS at leaf level were associated with lower SLA (p<0.001) and higher Tr in the abaxial leaf surface (p<0.05). Both leaf traits showed significant differences also within the south and east exposed plant category, thus suggesting the increase in leaf thickness and Tr as a potential adaptive strategy under multiple stress conditions. Our results provide evidence of a strong relationship between VFS, leaf traits and site-specific variables, offering new insights for interpreting data on the impact of ozone on vegetation.

Plants display a large number of traits which are reflected in physiological and ecological functions (functional traits). Leaf traits are amongst the most important functional traits. However, a great challenge in measuring leaf traits in the field is that direct methods are limited by the cost of the instruments and the time and work required by direct measurements, which are often destructive. As an alternative, we developed and tested a non-destructive methodology to assess a suite of leaf traits using different digital photographic approaches, with the intimate aim to develop a rapid, robust and cheap protocol for leaf trait measurements in the field. The proposed digital photographic approaches were tested in broadleaved tree species Digital photography allowed to assess a morphological foliar trait (leaf area; LA) and physiological foliar traits (leaf reflectance in red (R), green (G) and blue (B) bands; leaf venation attributes). Leaf area derived from photography significantly agreed with that directly measured with a leaf area meter (LA PHOTO = 0.98 LA AREA METER + 0.84, R 2 = 0.99, p < 0.001); leaf reflectance in the R, G, B channels derived from photography significantly agreed with that directly measured with a field spectroradiometer (SPEC) (R PHOTO = 0.77 R SPEC + 0.05, R 2 = 0.61, p < 0.001; G PHOTO = 0.79 G SPEC + 0.06, R 2 = 0.58, p < 0.001; B PHOTO = 0.56 B SPEC + 0.00, R 2 = 0.51, p < 0.001). Leaf venation traits estimated from photography agreed to within ± 20% measurements obtained in cleared leaves of the same species. Based on the obtained results, we demonstrated that digital photography can be an effective tool to obtain a fast, cheap, reliable and non-destructive assessment of morphological and physiological leaf traits in broadleaf tree species, being highly suitable for use in long-term research and monitoring programs.

Models which can predict crop yield loss using weed density or weed relative leaf area can be valuable decision-making tools for integrated weed management. Two field experiments were conducted to evaluate the goodness of fit of different yield loss models in corn-redroot pigweed system, during 2008 and 2009 growing seasons at the research field of Agricultural College of Shiraz University. The yield loss of the crop was recorded in experimental plots laid out in split plot design with three replicates. Main plots included five weed densities (0, 5, 10, 20, 30 and 40 weeds m -1) with subplots assigned with each of three different irrigation treatments as follows: T1=full irrigation and increasing soil moisture content in root depth to field capacity, T2=T1+25% and T3=T1-25%. Three empirical models characterized the relationship between redroot pigweed density or relative leaf area and corn yield loss under different irrigation conditions. These models included Cousens hyperbolic, Sp...

Plant species show considerable leaf trait variability that should be accounted for in dynamic global vegetation models (DGVMs). In particular, differences in the acclimation of leaf traits during periods more and less favourable to growth have rarely been examined. 2. We conducted a field study of leaf trait variation at seven sites spanning a range of climates and latitudes across the Australian continent. 80 native plant species were included. We measured key traits associated with leaf structure, chemistry and metabolism during the favourable and unfavourable growing seasons. 3. Leaf traits differed widely in the degree of seasonal variation displayed. Leaf mass per unit area (M a ) showed none. At the other extreme, seasonal variation accounted for nearly a third of total variability in dark respiration (R dark ).