Impact of leaf damage by defoliators on yield of soybean as a sole crop and as a main crop in intercropping systems |
| |
| Authors: | Kiran Gandhi Bapatla R H Patil Srujana Yeddula |
| |
| Institution: | 1. Department of Agricultural Entomology, University of Agricultural Sciences, Dharwad, India;2. ICAR – Indian Institute of Pulses Research, Kanpur, India |
| |
| Abstract: | Defoliators are common insect pests of soybean and often cause economic losses. Insecticides are the first option that farmers choose to minimize the damage caused by the defoliators, and the result is not only the emergence of resistance to insecticides in the pests but also environmental pollution. A field experiment carried out at the University of Agricultural Sciences, Dharwad, India, in 2013 and 2014 in the kharif season (June to September) tested nine intercrops in soybean – all grown as rain-fed crops – for their ability to reduce the damage caused by defoliators to soybean leaves and the effect on grain yield of soybean. Of the three species of defoliators, namely Spodoptera litura, Hedylepta indicata, and Diachrysia orichalcea, S. litura was the most severe. Maize and pigeonpea proved the most effective intercrops because of their phenology, repellent chemicals, and physical barriers and also because they were not the natural hosts of the defoliators and did not compete with soybean. In these two crops, the incidence of the defoliators and the extent of damage to soybean leaves were the lowest and the yields were the highest (3.56 t ha?1 in soybean–maize and 3.25 t ha?1 in soybean–pigeonpea). |
| |
| Keywords: | Defoliators soybean intercropping association yield |
|
|
