EXPLOITING WILD SPECIES AS SOURCE OF RESISTANCE AGAINST MAJOR PESTS AND DISEASES IN GROUNDNUT

Abstract

A field experiment was laid out at Regional Research Station, Vridhachalamduring  2020 with the already existing thirty numbers of groundnut wild species to explore and identify the resistance sources against major pests like leaf hopper Empoasca kerri, groundnut leaf miner, Aproaerema modicella and Spodoptera litura and diseases viz., leaf spots, rust, stem rot and root rot.Four observations were made at monthly intervals from the date of sowing in each season.Percent leaf damage by hopper,leaf miner,Spodoptera, percent disease incidence were observed and categorised as resistance or susceptible. A.villosa recorded 3.09% leaf hopper damage followed by A.helodes 3.55% are categorized as resistant to leaf hopper.A.villosa and A.helodes recorded late leaf spot and rust disease score of 1.A.villosa recoded 2.95%Stem rot and  2.2% root rot incidence.Specific leaf weight was minimum in  A.cardenasii(8216) (0.01 mg/cm2) and maximum was recorded in A.hermannii(13251)(0.12 mg/cm2).A.villosa (8144) recorded maximum abaxil surface trichome density of 53.33/0.25cm2and minimum in VRI 2 27.33 trichomes per 0.25cm2. Higher total phenol contents were observed in A.helodes (694.72mg/100g) followed by VRI-2(689.59mg/100g) but total tannin content was high in A.villosa(873.2mg/100g) followed by VRI -2(800.31mg/100g).Low total sugar content was observed in A.villosa(3.29%) followed by VRI-2(4.96%). Reducing sugar was less in A.villosa (0.70%) and non reducing sugars in A.helodes(1.70%).