Effect of organic manures, green leaf manures and micronutrients on natural enemies, sucking pest population, energy use efficiency and energy productivity

Abstract

The field experiment was carried out at MARS, Dharwad during Kharif, 2017-18 and 2018-19 to study the “Impact of organic manures, green leaf manures and micronutrients on natural enemies, sucking pest population, energy use efficiency and energy productivity. Among the nutrient management practices, EC (1/3) + VC (1/3) + gliricidia GLM (1/3) equivalent to RDF recorded significantly higher natural enemies’ population mainly coccinellids, syrphid maggots, Micromus timidis, chrysoperla and spiders’ plant-1 (0.80, 1.05, 0.88, 0.72, 1.30 and 1.28) over RDF + FYM (0.35, 0.44, 0.44, 0.44, 1.13 and 0.53, respectively). The foliar spray of panchagavya @ 5% recorded significantly higher natural enemy population viz., coccinellid beetles, syrphid maggots, Micromus timidis, chrysoperla and spiders plant-1 (0.67, 0.72, 0.64, 1.27 and 1.04 plant-1, respectively) over bio-digester @ 20% (0.57, 0.64, 0.57, 1.16 and 0.96, respectively). The combined application of EC (1/3) + VC (1/3) + gliricidia GLM (1/3) equivalent to RDF with foliar spray of panchagavya @ 5% recorded significantly higher natural enemies population mainly coccinellid adults and grubs, syrphid maggots, Micromus timidis, chrysoperla and spiders’ plant-1 (0.88, 1.13, 0.92, 0.75, 1.34 and 1.32 plant-1, respectively) as compared to RDF + FYM (0.25, 0.38, 0.36, 0.31, 0.74 and 0.31 plant-1, respectively). At 90 DAS, RDF + FYM @ 5 t ha-1 recorded significantly lower aphids and thrips populations (2.73, 1.42 per 3 leaves) over other nutrient management practices. The integrated application of EC (1/3) + VC (1/3) + gliricidia GLM (1/3) equivalent to RDN recorded significantly higher energy use efficiency and energy productivity (2.19 and 0.192 kg MJ-1, respectively) over FYM @ 5 t ha-1 + RDF. The combined application of EC (1/3) + VC (1/3) + gliricidia GLM (1/3) equivalent to RDN with foliar spray of panchagavya @ 5% recorded significantly higher energy use efficiency and energy productivity (2.20 and 0.192 kg MJ-1, respectively) over RDF + FYM.