Aim: Forecasting the incidence and severity of aphids, the major insect pest of wheat, is expected to significantly help in their management. In the present study, a set of weather-based models were developed to predict the timing and severity of Rhopalosiphum maidis infestation at Ludhiana falling under the North Western Plain Zone and R. padi at Niphad in the Peninsular Zone of India. Methodology: The weather indices-based regression models for two locations, Ludhiana and Niphad, were developed using the aphid population and weather data gathered over eight years (2006–14), and the models' predictive accuracy was successfully tested over four additional years (2014-18). The developed statistical models were transformed into three-tier architecture, web-based system, i.e. Presentation, application and data tier for dissemination of information. Results: The developed models can predict the crop’s age - when aphids first colonize the plants, when the aphid population attains the peak and the information about the peak intensity of the aphid population. For predicting the crop’s age at which population peaked at Ludhiana, the weighted interaction of the relative humidity (RH) in the evening and the number of hours of sunshine (NHS) along with the weighted interaction of minimum temperature and RH (morning) were important parameters while, at Niphad, the weighted NHS and the interaction of RH (morning and evening) were important. Likewise, for predicting the maximum aphid population at Ludhiana, the weighted interaction of minimum temperature and RH (morning) were important, while at Niphad, the key parameters were the weighted interaction of RH (evening) with the NHS. Interpretation: A prototype system developed to forecast the location-specific (Ludhiana and Niphad) infestation of wheat crops by aphids is expected to facilitate aphid management through an accurate forewarning at the locations.

Aim: To evaluate the efficiency of most effective trap among two types of sticky traps of, i.e., card or tray of two colours (yellow and blue) and their placement height within wheat crop for catching alate of R. maidis, the most abundant aphid species in selected locations. Methodology: Sticky card and tray traps of two colours; yellow and blue were placed at different heights within wheat crop and the effects of trap parameters (type, colour and height) were evaluated to determine the trapping efficiency of R. maidis alate. The traps were installed at two heights above ground level; 100 cm and 150 cm at Karnal and Ludhiana and at 60 cm and 120 cm above ground level at Niphad location. Alate aphid counts were recorded weekly to make comparisons. Results: The highest number of R. maidis alate were caught on yellow coloured sticky card traps placed within the crop canopy at 100 cm height above ground and the lowest on blue coloured sticky tray traps at 150 cm height above ground at Ludhiana and Karnal. At Niphad, the highest population was caught on yellow coloured sticky card traps placed at 60 cm height above ground and the lowest number on blue coloured sticky tray traps at 120 cm height above ground. Correlation analysis revealed that all three trap parameters (trap type, colour and placement height) were correlated with mean alate trap catches. Backward stepwise regression modelling indicated that trap type and placement height had a maximum influence on the R. maidis alate trapping. Interpretation: This study indicated that the yellow sticky card traps were most effective in catching R. maidis alate as compared to other tested traps. Key words: Aphids, Insect sampling, Trapping efficiency, Trap parameters, Triticum aestivum