Screening of wheat germplasm lines for identification of sources for yellow rust resistance in Kashmir valley
In India stripe rust of wheat (Triticum aestivum L.) is important as it occurs in the severe form in North Hill Zone (NHZ) covering states of Jammu and Kashmir, Himachal Pradesh and Uttarakhand. Stripe rust thrives well under cool and moist field conditions and sometimes its epidemic is so severe that it destroys the whole crop. Although the fungicides have been applied to control this disease but their use is unfriendly to the environment and they add to the input cost of farmers. The breeding for disease resistance is an effective strategy and involves identification of stable sources of resistance and their utilization. Deployment of yellow resistance genes has helped in suppressing the intensity, effectiveness and frequency of rust epiphytotics. Many sources of yellow rust resistance exist, but these are either incompletely characterized or these have not been studied in sufficient detail needed for their designation. The present study was conducted to screen for yellow rust resistance a set of 300 wheat germplasm lines received from various national and international germplasm centers viz., CIMMYT, Mexico; CIMMYT, Ankara, Turkey; IARI sub-station, Wellington, Tamil Nadu; IIWBR, Karnal; IIWBR, Flowerdale, Shimla and SKUAST-Kashmir, Srinagar for yellow rust resistance (46S119 and 78S84 as most prevalent races) over years 2012 to 2016 under field and ployhouse conditions. The study could identify eleven wheat lines showing varying levels of resistance to yellow rust races 46S119 and 78S84 when scored at adult plant stage under both conditions. The area under disease progress curve (AUDPC) scores of the lines identified as resistant was lowest as compared to yellow rust susceptible check (Agra Local). The resistant lines identified in the study could efficiently be utilized in yellow rust breeding programmes of the country and thereby deployment of such genes over space and time for an effective and long lasting control.