Weather based yield prediction model at various growth stages of wheat crop in different Agro Climatic Zones of Jammu region

Long term seed yield and weather data during growing period of wheat crop from 1991 to 2012 was collected from different offices or agencies for development of the district level yield forecast models. Further, the field experiments at research farm of Agrometeorology Section of SKUAST-J, Chatha, Jammu were also conducted in order to validate these models during rabi season of 2012-13 and 2013-14. Pre harvest yield prediction models for wheat crop has been prepared for different districts of Jammu region using this data. For the prediction of wheat seed yield at F2 stage, the long period weather data from 46th to 5th standard meteorological week (SMW) from 1991 to 2012 were used, where as at F3 stage, the data used from 46th to 9th standard meteorological week. The statistical weather based models for prediction of wheat yield for five districts of Jammu region were developed using the long term data. Models were validated with 2 years (2013 and 2014) data. For developing the yield forecast, models using composite weather variables have been studied. Simple and weighted weather indices have been prepared for individual weather variables as well as for interaction of two at a time considering throughout the crop growing season. The prediction models were able to explain the inter annual variation in the seed yield of wheat to an extent of 78, 74, 70, 73 and 68 percent and 82, 75, 76, 80 and 77 percent for Jammu, Kathua, Kishtwar, Udhampur and Doda districts during rabi 2012-13 and 2013-14, respectively. The validation results indicate that prediction of yield forecast is better for most of the Districts in 2014 as compared to 2013. The predicted rabi wheat yields for most of districts are within acceptable error limit (+/- 10 percent) in both the years of validation.