Rice false smut disease caused by the ascomycete fungus Villosiclava virens (Clavicipitaceae) reduces rice yield worldwide. It invades rice panicles and forms dark-green false smut balls composed of thick-walled conidia. Although the infection process during the booting stage is well studied, its infection route before this is unclear. It was hypothesized that the thick-walled conidia in soil penetrate rice roots, and the fungus latently colonizes roots and tiller buds at the vegetative stage. This hypothesis was tested using species-specific detection methods. First, real-time PCR with speciesspecific primers and probe was used to estimate thick-walled conidial number in the paddy field soil. Secondly, nested PCR with species-specific primers showed that fungal DNA was detected in roots and shoot apices of rice plants in the vegetative stage. Thirdly, colourimetric in situ hybridization with a species-specific oligonucleotide probe targeting 18S rRNA suggested that sparse mycelia or tightly condensed mycelia were present on the external surface of tiller buds enveloped by juvenile leaf sheaths at the vegetative stage. Thin hyphae were found around leaf axils at the surface of elongated stems at the heading stage, and the fungal hyphae grew in the rice root tissues. In addition, it was demonstrated that eGFP-tagged transformants of the fungus invaded rice roots and colonized the surface of roots and leaf sheaths under artificial conditions.

Two newly bread wheat cultivars Misr 1 and Misr 2 were selected from CIMMYT wheat genotypes as resistant to stem rust specially the race Ug 99. Grain yield and rust resistance evaluation was performed through preliminary, advanced and varietal verification started in 2009/2010 through 2012/2013 growing seasons, compared to the check bread wheat cultivated cultivars. The results reveled that the grain yield of Misr 1 and Misr 2 exceeded wheat check cultivars in most of the tested locations. Generally, the new cultivars mean grain yield exceeded all the check cultivars means in preliminary, advanced and varietal verification yield trials and have high stable parameters allover the wheat cultivated areas. Testing the two new cultivars for stem and yellow rusts reaction, in the hot spots in Egypt, Uganda, Kenya and Ethiopia, indicated their resistance to stem and yellow rusts. Thus they could be highly recommended to be grown all over Egypt.

Fifty bread wheat lines were evaluated for heat tolerance and compared to some local cultivars under three sowing dates (November 25th, December 15th and January 5th). Four agronomic traits were evaluated, i.e. No. of spikes per plant, grain yield per plant, 100-kernel weight and harvest index under normal and stress conditions. Analysis of variance showed highly significant variations among the tested lines and demonstrating that the main effect of sowing dates was due to the late date. Grain yield per plant was the most affected trait by heat followed by 100-kernel weight and No. of spikes per plant, while harvest index showed the lowest reduction due to heat stress. Six lines (L1, L11, L16, L34, L37 and L41) showed heat tolerance based on high performance in grain yield/plant by 29.45, 29.75, 27.75, 27.43, 27.37 and 31.90 g, respectively under late sowing conditions as well as low heat sensitivity index. The sequence related amplified polymorphism (SRAP) was able to differentiate between bulked DNA samples of lines with the highest and lowest performance in agronomic traits under heat stress. SRAP generated 2, 1 and 3 bands specific for lines with high performance of No. of spikes per plant, grain yield per plant and harvest index, respectively as well as it showed 5 and 3 bands specific for lines with low performance of grain yield per plant and harvest index, respectively. These specific bands could serve in wheat genotyping and screening, and might be used as SRAP markers associated with heat tolerance in wheat breeding programs.

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