Evaluation of Various Pest Management Modules Against Rice Yellow Stemborer, Scirphopaga incertulas (Walker) (Crambidae: Lepidoptera)

Abstract

Background: Globally, rice yellow stem borer alone causes yield losses of 10 m t accounting for 50 per cent of all insecticides usage in the rice field farmers depend upon a plenty of insecticide applications, even though a lot of insecticide applications are not effectual (Sarwar et al., 2005). The over- reliance on use of chemicals to manage this pest had lead to numerous undesirable consequences like disrupting natural enemy complexes, secondary pest outbreaks, pest resurgence, development of insecticide resistance and environmental pollution. Keeping in view the deleterious effects of chemical pesticides, there is a need to evaluate alternate methods or integrated methods to manage the rice stem borer effectively without any menace to the ecological niche. Hence, a research trial was conducted to evaluate the efficacy of various pest management modules against rice stem borer in comparison to farmers practice and sole chemical control, besides in concern to yield and cost economics. Methods: The field efficacy of various pest management modules viz., non-chemical based, non-chemical + biorational methods, chemical-based, IPM module and farmers practice against rice yellow stem borer were evaluated during the wet season and dry seasons of 2016 and 2017. The experimental was laid in a net area of 10 m x 20 m each plot laid in Randomized Block Design which comprised of five treatments (modules) with four replications. The incidence of rice yellow stem borer (YSB) in various modules in terms of percent dead hearts (% DH) during tillering stage and percent white ears (%WE) during maturing stage were recorded. Result: It was evident from the pooled mean data that among various modules, the least per cent dead hearts (2.68 and 2.56% DH ) and white ears (2.79 and 2.31% WE) were registered in IPM based module followed by farmers practice (2.31 and 2.32% dead hearts and 3.92 and 4.77% white ears) and chemical-l based module (2.90 and 4.24% dead hearts and 5.59 and 5.18% white ears) as against highest incidence in non- chemical (13.78 and 13.7% dead hearts; 18.24 and 17.94% white ears) and non- chemical + bio rational (11.40 and 9.88% dead hearts; 13.09 and 11.25% white ears ) based modules during the wet season and dry season, respectively.