Status of Seed Health and Facultative Foliar Pathogens of Wheat in Punjab From 1992–99

Wheat is a premier Rabi crop in the state, cultivated mainly under irrigated high fertility conditions in rotation with rice. This annual monoculture got further reinforced with staggered planting of early normal and late sown varieties. In the last decade the frequency of black point affected, dis-colored, shriveled seed and foliar pathogens in the crop likely to become serious were monitored. Overall the black point incidence was widely prevalent in the state, fluctuating from 0.21 to 0.99%, in 62–86 percent samples from 1992–99. Mean incidence of shriveled grains was relatively higher (1.4%). In the black point syndrome, seed infections was due to D. sorokinians followed by Fusarium spp. Grain shriveling was due to high temperature in 1996, however subsequently, the incidence of Fusarium and Alternaria spp were seen to increase. There was no evidence of reduced seedling stand in the farmers field but in laboratory conditions the affected seed germinated poorly with reduced seedling vigor. Foliar blight pathogens remained in low incidence till 1995. In 1996 and un-precedent severity of leaf blight due to Drechlera sorokiniana and Fusarium species occurred widely, resulting in severe set back to HD 2329 and Durum cultivation, which was being given thrust for export purpose.