Evaluation of Wheat landraces of National Plant Gene Bank of Iran for Resistance to Powdery Mildew Disease

Wheat powdery or superficial mildew caused by Blumeria graminis f. sp. tritici has been one of the most important wheat diseases in the world. It has been prevalent in Mazandaran province that is an important region of epidemic which causes considerable yield damage. Due to preparation and cultivation of resistant varieties is most appropriate method for disease control and Pathogen population always evolved therefore new source of resistance sources should always be investigated. In order to evaluate the wheat land race collection of National Plant Gene-Bank of Iran to Mildew disease 1800 accession were evaluated observationally during three years from 1384 to 1387 in Qarakhyl station, Mazandaran. Cultivars Shanghai, Tajan and Bolani were planted with in each block. Bolani sensitive cultivar was cultivated around the blocks as disease spreader on the sidelines. Reaction of under study accessions to powdery mildew were recorded based on Sari and Prescott method base on disease severity and disease incidence. The results indicated that land races evaluation of 9 percent in the first year, 8 percent in the second year and during third year 55 percent of the indigenous landraces belong to National Plant Gene-Bank of Iran wheat collection were immune to wheat surface Mildew disease. Thirty five lines from germplasms under study during three year primary phase of study separated according to different level of resistance to powdery mildew and along with improved breeding lines that already used on fifteen percent of local wheat growing area selected for experiment in fourth year were studied by incomplete block statistical design in the form of triple lattice. Performance and number of grains per spike had the highest variability and number of floret per spikelet and number of nod per stem had the lowest variability during last phase of study. Wheat accessions TN.12494, KC.299, TN.10600 and N-80-19 had higher seed yield compared to other accessions under study.