To save the crops from stripe rust disease, known as yellow rust, the Directorate of Wheat Research, Karnal has issued a warning to farmers of Himachal Pradesh against the disease.
A release issued here by the Institute said a stripe rust survey, was conducted extensively in Kullu district of HP on June 4-5, by Dr Indu Sharma, project director, DWR, Karnal and CSKHPKV Regional Research Centre, Bajoura (Dr Rakesh Devlash, Dr Gurdev Singh, Dr Naval Kishore).
The survey was undertaken as wheat crop was at different stages of maturity in this region.
At some places, the crop was harvested whereas in other areas it was ready to harvest. According to reports, the disease has affected wheat growing areas of Himachal Pradesh, Haryana and Punjab.
Due to untimely rain in recent times, thousands of acres growing wheat have been affected by the disease.
Close observation of the dried leaves revealed the teliospore stage of stripe rust at Bajaura and other areas between Kullu to Bhaliyani.
Stripe rust uredospores were also observed in high hills in Himachal Pradesh.
In different fields, the intensity of the stripe rust disease varied from 10S to 80S.
In Bragran and Bhaliyani villages, the disease intensity was 60-80S in wheat sown under apple trees.
The stripe rust was also observed in self sown wheat. There is a likelihood that this stripe rust infected wheat crop serves as a green bridge and the uredospore inoculum from Kullu and further gets carried away with wind currents in Lahaul valley in July where the crop is sown in May-June.
Though rust could not be found on the grass but intensive surveillance might reveal some grasses harbouring the uredospore inoculum.
The crop at Lahaul is harvested in September and there is a lapse of three weeks to one month in October when the areas between Lahaul and sub-mountain tracts are devoid of any crop.
As the temperature dips, the crop matures at Lahaul and uredospores could survive as such on dried leaves.
The uredospores either surviving as such under cooler temperatures at Lahaul and uredospores on self sown crop could serve as a source of inoculum for the crop sown in adjoining hilly areas of Himachal Pradesh and sub-mountain areas of Punjab in the regular wheat crop sown in November/October end.
In general, the disease in high intensity has been observed in areas adjoining Satluj and Beas.
In Haryana also, the disease is of high intensity in adjoining areas in Yamuna belt of Yamunanagar district.