STRATEGIC MANAGEMENT OF INSECT PESTS OF PIGEONPEA (Cajanus cajan L.) WITH PARTICULAR REFERENCE TO POD BORER COMPLEX
Loading...
Date
2012
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Birsa Agricultural University, Kanke, Ranchi, Jharkhand
Abstract
Pigeonpea yields have remained stagnant for the past 3-4 decades due to variety of
factors, of which losses caused by insect pests have been considered as the most important.
About 150 insect pest species have been recorded to be feeding at various stages of its growth
in India (Patel et al., 2002). Among the various insect pests, pod borers are mainly responsible
for causing loss in yield. Several pod borers, viz., the gram pod borer (Helicoverpa armigera),
plume moth (Exelastis atomosa), spotted pod borer (Maruca testulalis), pod fly(Melanagromyza
obtusa), spiny pod borer (Etiella zinckenella), etc. which together form the pod borer complex,
have been found to cause heavy damage to floral parts as well as pods resulting in excessive
loss in grain yield of pigeonpea.
Considering the importance of pigeonpea crop and damage caused by pod borer complex, field
experiments were carried out during kharif, 2011-12 to develop an effective pest management
strategy for sustainable crop production.
The outcome of the research could be summarized as -
In total, 12 insect species were recorded during the course of investigation. However, only
three species (H.armigera,M.testulalis and E.atomosa) were found in appreciable number from
flowering till harvest of the crop. The rest species noticed were very less in number.
The effect of different abiotic factor on the occurrence of these pests was also studied. The
Maruca borer was recorded in 44thstandard week and remained active up to the first week of
January, 2012. Incidence of H.armigera was observed to be maximum (4.86 larvae/ plant)
during 51st standard week.Maximum (4.85 larvae/ plant) incidence of plume moth was also
noticed during 51st standard week. It was also revealed that the larval count of H.armigera
showed strong negative correlation with minimum temperature and RH at 2pm whereas,
M.testulalis was highly significant but negatively correlated with maximum temperature. On the
other hand, E.atomosa showed significant and negative correlation with maximum and
minimum temperature.
Field experiment on varietal screening revealed that out of the 14 genotypes tested,
PA374 (1.7%) and UPAS 120 (2.0%) recoded the lowest pod damage and was considered to be
least susceptible to pod borer complex. Highest grain yield was also recorded in the above
cultivars. BRG 1101 with 36.3 per cent pod damage was considered to be most susceptible
against pod borer complex.
The studies on influence of intercrops on pod borer population indicated that pigeonpea
when intercropped with horse gram recorded the lowest (4.05/ plant) larval population. Similar
trend were recorded in different pod borer species also. Pigeonpea grown with either
horsegram or blackgram, recorded about 70 per cent reduction in grain damage over sole crop.
However, pigeonpea+coriander gave the higher yield and there was an increase of 95.98 per
cent in yield as compared to pigeonpea sole crop.
In another set of experiment, eight insecticides/ biopesticides and one untreated control
were evaluated against pod borer complex .The treatment comprised of five insecticides and
three biopesticides. Each treatment was applied twice at an interval of 20 days starting from 14
December when 50 per cent flowering was noticed .The mean larval population was
significantly lowered in Indoxacarb 14.5SC @60g a.i./ ha against all the species of pod borer
followed by Flubendamide 480 SC@48 g a.i./ha. The treatment recorded Highest (9.52 q/ ha)
seed yield was obtained in Indoxacarb (1: 8.96) followed by Spinosad (1:7.65).
Description
STRATEGIC MANAGEMENT OF INSECT PESTS OF PIGEONPEA (Cajanus cajan L.) WITH PARTICULAR REFERENCE TO POD BORER COMPLEX
Keywords
null