Powdery Mildew Infection on Some Egyptian Bread Wheat Cultivars in Relation to Environmental Conditions.

Abstract

Wheat powdery mildew, caused by the biotrophic fungus Blumeria graminis (DC) E.O. Speer f. sp. tritici Em. Marchal, is one of the most severe foliar diseases attacking this crop, affecting wheat production under Mediterranean basin conditions through the last few years. Four bread wheat cultivars i.e.. Sakha-93, Gemmeiza-7, Gemmeiza-10, and Giza-160 as a check were evaluated to artificial inoculation of powdery mildew under field conditions. The tested wheat cultivars showed susceptible responses to powdery mildew with fluctuated values in 2010 and 2011 seasons. In 2010 season, the tested cultivars showed high levels of disease severity, ranged from 35 to 87 % (Gemmeiza-7 and Gemmeiza-10, respectively). While, in 2011 lower levels were recorded, from 6.00 up-to 15% (Sakha-93 and Gemmeiza-10, respectively). Area under disease progress curve (AUDPC) was correlated with disease severity during the two seasons. Also, the yield components, the thousand grain weight and the grain yield/m 2 were affected by disease severities with different values for each cultivar. High air temperature, wind speed and mild relative humidity played an important role in increasing powdery mildew infection level in 2010 season.

Partial resistance to powdery mildew and leaf rust of wheat in Egyptian and CIMMYT genotypes

“…tritici (Bgt) and Puccinia triticina (Pt) collected from different places and different years, but they recorded the longest incubation period (IP) and latent period (LP) at the seedling stage. They, therefore, appear to have good partial resistance to both diseases (El-Shamy et al, 2012;Draz et al, 2015;Abdelrhim et al, 2018).…”

Grain Yield and Quality of Some Egyptian Wheat Varieties as Influenced by Powdery Mildew Infection

“…According to the obtained results and depending on the values of AUDPC, it could be stated that the wheat varieties Giza 168, Misr 1 and Sids 12 showed high and appropriate levels of adult plant resistance to powdery mildew infection under field conditions during the two seasons. These varieties showed the lowest values of AUDPC less than 300 (El-Shamy et al, 2012).…”

“…Tomas and Solis (2000) concluded that the reduction in grain yield of the durum wheat cultivars in South of Spain was mainly caused by powdery mildew infection. El-Shamy et al (2012) found that the highest reduction in yield components was detected in cv. Gemmeiza 10 i.e.…”

“…On the other hand, Sakha 93 exhibited the highest disease severity (38.33% and 51.66%) during the two successive seasons. The variation in disease severity among different varieties and growing seasons were also represented by others (Vechet, 2006 andEl-Shamy et al 2012).…”

Novel genomic regions on chromosome 5B controlling wheat powdery mildew seedling resistance under Egyptian conditions

“…One of the major devasting foliar diseases that reduce wheat crop and quality is powdery mildew (PM) caused by Blumeria graminis f.sp tritici ( Bgt ) ( Singh et al., 2016 ; Figureueroa et al., 2018 ). In favorable conditions, PM infection could cause yield losses of up to 62% in many wheat planting areas ( Costamilan, 2005 ; Maxwell et al., 2009 ; El-Shamy et al., 2012 ; Huang et al., 2013 ). Recently, PM was reported to occur annually in Egyptian fields and is considered more dangerous than rusts that have been effectively controlled ( El-Shamy and Mohamed, 2022 ).…”