Rice weevil

The present study was conducted to screen out six rice genotypes including two course and four fine advanced varieties against Coleopterous insect rice weevil, Sitophilus oryzae (L.) under laboratory conditions. Weighing 100g sample of each genotype in plastic jars having capacity of 250g. Thirty adult insects of rice weevil, reared in laboratory were released in each jar. Quantitative losses as weight loss, percent damaged grains, progeny development and frass weight was recorded after 90 days of storage at 28oC, 32oC and 35oC. Percentage damage grains, adult emergence and frass weight was significantly high at 32, 28 and 35°C respectively. Maximum infestation in case of percentage damaged grains recorded in course genotype KSK-133(20.58%) and Basmati-515(16.90%) followed by Basmati-2006(13.033%), and Super Basmati (12.433%) at 28°C. In a similar way but minimum weight loss (0.5%) was observed in KSK-282 at 35°C and (1%) in Basmati-2006 at 32oC. Overall, low resistance level with highest insect development was counted in

This paper presents the process of microwave heating treatment to kill the rice weevil to improve the quality and quantity of rice for industrial storage purpose. Since many years ago, heat uniformity has been a major drawback of microwave heating application. The heat distribution in rice after undergoing four treatments with a microwave frequency of 2.4 GHz at the different power level of 540 and 900W with different time treatment of 50 and 80 seconds are shown in this paper. The samples are placed inside a square container, 8.5 cm x 8.5 cm x 2 cm. Each sample contains 15 adults of rice weevil of Sitophilus Oryzae placed randomly in the container and the mortality of the rice weevil for adult stages from each treatment are observed and interpreted in Analysis of Variance (ANOVA) technique.