Assessment and quantitative analysis of losses due to Drechslera maydis in maize

摘要

In Indian maize programme, development of early maturing varieties and composites has been given greater emphasis due to their preference by farmers of the major maize growing areas. It was, therefore, decided to obtain an idea about the losses causedby Race 'O' D. maydis incitant of Maydis leaf blight of maize, in the released promising composites and also in a early maturing Pop Corn variety. As the objective of this experiment was to assess the yield loss at the maximum level of infection, it wasdecided to obtain data on individual plants which has shown a disease rating of 4.0 or more, on a scale of 1-5, with one indicating no disease and 5 indicating the highest level of infection. The results averaged over the three years, indicated substantial loss in yield by Maydis leaf blight Maximum yield reduction of 41% was observed in Pop Corn variety. The other two composites namely Pusa composite I & Arun suffered yield loss of 27% and 28%, respectively.