Aegilops speltoides is an important genetic resource for wheat improvement and has high levels of heat tolerance. A heat-tolerant accession of Ae. speltoides pau3809 was crossed with Triticum durum cv. PDW274, and BC 2 F 4-6 backcross introgression lines (BILs) were developed, phenotyped for important physiological traits, genotyped using SSR markers and used for mapping the QTL governing heat tolerance component traits. A set of 90 BILs was selected from preliminary evaluation of a broader set of 262 BILs under heat stress. Phenotyping was conducted for physiological traits such as cell membrane thermostability, chlorophyll content, acquired thermotolerance, canopy temperature and stay green. Much variation for these traits was observed in random as well as selected sets of BILs, and comparison of the BILs with the recurrent parent showed improvement for these traits under normal as well as heat stress conditions, indicating that introgressions from Ae. speltoides might have led to the improvement in the heat tolerance potential of the BILs. Introgression profiling of the 90 BILs using SSR markers identified Ae. speltoides introgression on all the 14 chromosomes with introgressions observed on A as well as B genome chromosomes. QTL mapping identified loci for various heat tolerance component traits on chromosomes 2B, 3A, 3B, 5A, 5B and 7A at significant LOD scores and with phenotypic contributions varying from 11.1 to 28.7 % for different traits. The heattolerant BILs and QTL reported in the present study form a potential resource that can be used for wheat germplasm enhancement for heat stress tolerance.

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Tomato is the most widely eaten vegetable and used as a good source of vitamins A, B, C, and D and minerals such as calcium, phosphorus, and iron. The study was done to evaluate the effect of Bacillus species isolated from the sediment of Lake Tana on the early growth of different tomato (Solanum lycopersicum L.) varieties. All Bacillus isolates significantly ( P < 0.05 ) increased the growth of all three tomato varieties in terms of shoot length, shoot fresh weight, shoot dry weight, root length, and fresh and dry weights of the root. The isolates’ efficacy varied among tomato varieties. Bacillus isolate B2 was more effective in the Maya variety, with a potency of 85% and 71.2% shoot and root lengths, respectively. Bacillus isolate B3 was more efficient in the Melkesalsa variety, with a shoot and root length efficiency of 57% and 68%, respectively. Bacillus isolate B1 was more successful in the Kochero variety with 65 and 70% shoot and root length efficacy. Individual isolates’ PGPR characteristics differed, resulting in a wide range of effectiveness among different varieties. More research studies are needed to fully know the mechanism of action and efficacy of these isolates in the field. The isolates must also be identified using molecular techniques.

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