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Stripe (yellow) rust disease caused by Puccinia striifarmis f. sp. tritici, is a catastrophic wheat disease in wheat-growing regions around the world. The objective of this study was to investigate potential sources of stripe rust resistance and the yield loss of forty local wheat varieties at four locations in Egypt (Sakha, Mutubas, Qillin and Biyala), under yellow rust disease pressure compared to 'Morroco' variety, as control. To determine slow rusting in the field, the following parameters were recorded: final rust severity (FRS%), average coefficient of infection (ACI), relative resistance index (RRI) and reduction % in the 1000 kernel weight. The severity was higher in the second season than in the first. Seven wheat genotypes ('Shaka 62', 'Shaka 9, 'Shaka 95', 'Gemmiza 7', 'Sids 14' and 'Misr 3') showed the high level of resistance, and FRS% values ranged from 0 to 20 moderately resistant (MR) during first season and achieved the least value of loss in TKW (1.28%) with 'Misr 3'. Meanwhile, four genotypes ('Sakha 93', 'Sakha 95', 'Sids 14' and 'Gim. 7') remained highly resistant during the second season and identified to have good level of slow rusting resistance, which these genotypes showed FRS% values ranged from 5R to 30 moderately resistant-moderately susceptible (MRMS), ACI values < 12, RRI values >6 and the loss % in TKW not exceed 12.54%. On the other hand, the lines; 'Shaka 69', 'Shaka 88', 'Shaka 92', 'Giza 160', 'Giza 163', 'Gem IT, 'Sids 2' and 'Sids 6' exhibited complete susceptibility at the four tested sites, recorded FRS% values >50. Meanwhile, cv. 'Gem IT in 2018/2019 recorded the highest level of ACI >55, the lowest level of RRI<4.05 and the highest loss% in TKW reached 40.69%. These findings could be used in the national wheat breeding program for stripe rust resistance in Egypt. [ABSTRACT FROM AUTHOR]

Sixteen rice genotypes were planted under normal and high temperature during 2018 and 2019 seasons to understand the mechanisms that make plants tolerant or susceptible to heat stress and methods which may lead to generate new varieties with sustainable yield production. The combined analysis showed significant differences at the level of probability 0.05 and 0.01 among years for all characters except, chlorophyll content and leaf rolling which would indicate wide differences among the weather of both years. Environment's variance was significant at the level of probability 0.01 over all characteristics. The significant differences at the level of probability 0.01 were recorded among genotypes and G x E interaction variances for all characteristics. The highest values of panicles number plant-1 were obtained from 'Giza 178' and 'Hybrid 2', however, the highest values of 100-grain weight were recorded with 'Giza 179' and 'Egyptian Yasmine'. The minimum values of sterility% were recorded with 'Sakha 107' and 'IET1444'. Concerning the cultivars performance across two environments, the cultivars 'Giza 178', 'Giza 179', 'Sakha 107' and 'IET 1444' gave the best desirable values over natural and heat stress so, those cultivars are considered to play a vital role in breeding program to enhance heat stresses tolerance accompanied with high yield potential. [ABSTRACT FROM AUTHOR]