Effect of Bio-organic Amendments on the Infestation of Major Pests & Foliar Disease, Leaf Productivity in Mulberry (Morus alba L)

Abstract

Massive utilization of inorganic fertilizers for a prolonged period leads to alteration of the soil chemical properties, the availability and uptake of nutrients by the plants. The field experiments aimed at investigating the effect of bio-organic amendments on infestation of major pests, foliar disease and leaf productivity of mulberry (Morus alba L) have been conducted during March 2004-February 2007 in lateritic soil condition (having around pH of 5.6) with limited irrigation support in some areas of Midnapur (West) Districts, West Bengal, India. The research was set up as randomized block design, consisted of five treatments and provided with three replications. (T1 = 20 MT/ha FYM + 336 kg N+180 kg P2O5+ 112 kg K2O /ha /yr, T2 = 10 MT/hc Vermicompost + Azotobacter +AMF + 50% N + 33% P2O5 and K2O /ha /yr of T1, T3 = 7 MT/hc of Poultry-manure + Azotobacter +AMF + 50% N + 33% P2O5 and K2O /ha /yr of T1, T4 = 5 MT/hc Vermicompost + Azotobacter +AMF + 50% N + 33% P2O5 and K2O /ha /yr of T1, T5 = 3.5 MT/hc Poultry-manure + Azotobacter +AMF + 50% N + 33% P2O5 and K2O /ha /yr of T1). The experimental results revealed that the effect of vermicompost in combination with bio-fertilizers followed by reduced doses of inorganic fertilizers imparted significant effect on leaf productivity and incidence of pests and diseases of mulberry plants. However, maximum leaf yield was recorded with the application of poultry manure along with bio-fertilizers and reduced dose of inorganic fertilizers (T3) in the third year after the establishment of plants (16.98 MT/ha/yr). Study of surveillance on the incidence of disease and insect pests clearly indicated that no other diseases than foliar disease was recorded under different manurial and fertilizer treatments. Further, population of the insect pests like white fly and thrips were found to be significantly reduced below the economic threshold level in the experimental plots treated with different organic manures along with bio fertilizers over control.