Effect of temperature and humidity regimes on grain mold sporulation and seed quality in sorghum (Sorghum bicolor (L.) Moench) Abstract Grain mold, induced by a number of non-specific fungi, causes substantial loss to seed/grain yield and quality in sorghum (Sorghum bicolor (L.) Moench). Fungal sporulation and grain mold severity are greatly influenced by temperature and relative humidity (RH) levels. We studied the effects of three incubation temperatures (25, 27 and 288C) and two sets of RH levels (first set: 85, 90, 95, 98, and 100%, second set: 95, 96, 97, 98, 99 and 100%) on sporulation and grain mold severity in three major mold fungi (Curvularia lunata, Fusarium moniliforme, and Bipolaris australiensis) and on four each of resistant, moderately resistant and susceptible sorghum genotypes for sporulation and mold severity of major fungi. Results indicated that both fungal sporulation and grain mold severity increased on most sorghum genotypes with increasing incubation temperature from 25 -288C and RH levels from 95 -98%. A linear relationship was observed among RH levels, grain mold severity and fungal sporulation. The highest sporulation of all the three fungi occurred at 288C and 98% RH after 5 days of incubation. Among the three fungi, C. lunata grew and sporulated faster than B. australiensis and F. moniliforme, in that order. Among the sorghum genotypes, IS 25017 supported the least sporulation and had the lowest mold severity, followed by IS 8545 and PVK 801. Seed quality parameters, such as seed germination, seedling vigor index, field emergence potential, dehydrogenase and þ-amylase activities declined significantly with increasing temperature and RH levels that supported heavy sporulation and grain colonization.

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Use of synthetic insecticides for the management of fall armyworm (FAW) Spodoptera frugiperda (J. E. Smith) for a longer period will led to development of insecticide resistance. Identification of an eco-friendly synergistic agent to enhance the toxicity potential and reduced pesticide use as well become mandatory in due process. Hence the present study was formulated to find the single and combined toxicity of chlorantraniliprole and Bacillus thuringiensis (Bt) against the 2nd and 3rd larval instars of S. frugiperda. Single toxicity of chlorantraniliprole against 2nd and 3rd larval instars were 0.87 and 1.52 ppm (LC25); 4.08 and 6.50 ppm (LC50), respectively. With respect to Bt, single toxicity against 2nd and 3rd larval instars were 474.39 and 693.48 ppm (LC25); 1008.62 and 1228.62 ppm (LC50), respectively. Combination effect of chlorantraniliprole with Bt revealed that 2nd instar of FAW showed supplemental synergism at LC50 of chlorantraniliprole + LC25 of Bt. In the case of LC50 of chlorantraniliprole + LC50 of Bt, LC25 of chlorantraniliprole + LC50 of Bt and LC25 of chlorantraniliprole + LC50 of Bt combinations, they showed sub additive synergism. In 3rd instar larvae, the combined toxicity results were similar for all the combinations of chlorantraniliprole + Bt except LC25 of chlorantraniliprole + LC50 of Bt where it showed an antagonistic synergism. Activity of Carboxyl Esterase (CarE), Mixed Function Oxidase (MFO) and Glutathione-S-Transferase (GST) were found to be lesser in chlorantraniliprole LC50 + Bt LC25 combinations than single toxicity treatments. Therefore, combined use of chlorantraniliprole with Bt at LC50 of chlorantraniliprole + LC25 of Bt had supplemental synergism on fall armyworm under laboratory condition.

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Iron (Fe) and Zinc (Zn) are the most essential micronutrients needed for the growth and metabolism of higher plants. Fe and Zn has important role as a component of various enzymes that are involved in chlorophyll biosynthesis, photosynthesis and seed development. Plants have evolved with multifaceted Fe and Zn homeostatic mechanisms that regulate its acquisition from the environment and the movement between organelles, cells, tissues, and organs. In addition, Plant establishes a tightly controlled system including metal specific uptake transporters and transcriptional regulators to balance the uptake, utilization and storage of metal ions. Barnyard millet (Echinocloa frumentaceae), one of the minor millets is superior in Fe and Zn content compared to the most widely consumed cereals like rice and wheat. In the present study, ionomic profiling of grains of several barnyard millet accessions revealed that accession ACM-10-145 accumulates high Fe and Zn content (Fe: 14.5 mg/100g; Zn: 2.18 mg/100g). Furthermore, transcriptomic studies are in progress to understand the key factors involved in metal uptake and translocation in barnyard millet. The research outcome could be exploited for biofortification program in cereals.