Parental, F1 and F2 sorghum [Sorghum bicolor (L.) Moench] populations involving the bloomless trait were studied for their reaction to greenbugs (Schizaphis graminum Rondani). Plants were grown in pots in the greenhouse, classified into bloom or bloomless (presence or absence of white wax on leaf sheath) categories, rated for greenbug damage, and studied for tolerance, anti. biosis, and non preference. The objective of the researchwas to learn more about the nature of the resistance of bloomless sorghum to greenbugs since bloomless may be useful in commercial sorghums. Bloomless was inherited as a simple recessive with complete dominance of bloom. The tolerance to damage of ‘Shalin Grain’ and ‘IS 809’ by greenbugs was inherited independently of the bloomless trait. The bloomless plants did not exhibit greenbug tolerance as did Shallu Grain and IS 809, except where the two traits were combined in an F2 individual plant. Bloomless plants showed only slightly more of an antibiotic effect on greenbugs than the susceptible check and significantly less than the resistance check. In this study, bloomless plants 50 to 70 days old exhibited a significant nonpreference to greenbugs compared to the susceptible check.

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In order to evaluate the reaction of yield and yield components of wheat's mutant lines to different levels of nitrogen in the crop year of 2006-2007, an experiment was conducted as factorial based on completely randomized block design in 4 replicates in the Research Farm of Agricultural, Medical and Industrial Research School in Zaferaniyeh-Karaj-Iran the first factor included 5 genotypes of wheat (Tabasi-the maternal entity, T-65-7-1, T-65-5-1, T-6-67-60, T-65-58-8) and the second factor consisted of 4 levels of nitrogen (100, 140, 180 and 220 kg ha(-1) urea 46%). The result showed that grain's yield harvest index, number of grain/spike in mutant lines and their parent had significant difference (p < 0.01) in mutant genotypes, meanwhile, the biological yield and the number of spike m2 were not significant difference (p < 0.05). The harvest index, number of grains per spike, grain's yield, biologic yield and number of spikes m(-2), weight of 1000 grains didn't affected by applying different levels of nitrogen fertilizer.