Background: The spotted pod borer (SPB), Maruca vitrata Fabricius is a key insect pest of major legume crop i.e. pigeonpea, Cajanus cajan in India and semi-arid tropics. Identifying a SPB resistant genotype will help in sustainable management of SPB and in attaining nutritional security. The SPB has developed insecticide resistance to most of the chemical insecticide like Organophosphorous group of insecticides and also it is expanding its geographic limits. These factors are the driving forces for identifying tolerant genotypes for its sustainable management along with a suitable biorational.

Methods: Forty seven pigeonpea genotypes were screened during kharif 2015 to 2017 at ICAR-IIPR, Kanpur based on percent pod damage and Pest Resistance Susceptibility Rating (PRSR) under insecticide free condition. The 4 biorationals were tested against SPB in ICPL 87 along with untreated control in Randomised Block Design. Further the SPB molecular identity was confirmed by phylogenetic analysis of partial Cox 1 gene amplified from M. vitrata adult.

Results:&nbsp;Two indeterminate genotypes (Pusa2001 and Pusa33) as SPB resistant based on lowest mean pest resistance susceptibility rating (PRSR 1.7) The next best genotypes were a determinate (AL-15) and indeterminate genotype (LRG-30) with a PRSR of 2.0. The highest PRSR (6.0) was recorded from the ICPL 87, a susceptible check in the present experiment. Spinosad 45SC has recorded significantly lowest mean pod damage (6.67%) and highest mean yield (4.36kg/35m2) compared to 4 other treatments in the field efficacy trial. The phylogenetic analysis of Cox 1 gene from Kanpur population (KY559101) with 19 other M. vitrata populations in India revealed that it is more similar to Raichur population (KT070892) and it confirms M. vitrata has same ancestral homology in India.

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Assessing Pigeonpea Genotypes for Resistance against Maruca vitrata Fabricius and its Sustainable Management through Biorationals

<div>Background: Legume pod borer or spotted pod borer, Maruca vitrata is one of the serious insect pest to the green gram, which causes damage mainly at the reproductive phase of the crop growth. The larvae of spotted pod borer are known to cause damage by webbing the leaves, bud, flower and pods together and feed from inside on them. Due to its webbing nature, it is very difficult to enter inside by natural enemies and chemicals cannot directly reach inside webbing. Host plant resistance to insect pests is an economically and ecologically preferred alternative as compared to other pest management tactics, particularly the synthetic pesticides. The present investigation was undertaken to examine the role of certain bio-chemical constituents of the immature pods of green gram in the expression of damage by the spotted pod borer. 
 
Methods: The experiments on screening were conducted during the kharif 2014 and 2015 at the Agricultural Research Farm, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, (U.P.) to define the occurrence of M. vitrata on 20 promising varieties/genotypes of green gram. Pods were collected at the immature stage from different varieties/genotypes and biochemical constituents such as total soluble sugar, total chlorophyll, protein were estimated. 
 
Result: The maximum protein content was found in genotype IPM 306-6 (36.17 mg/g) and minimum in genotype PM-5 (20.53 mg/g). Highest total sugar content was reported from genotype ML 1256 (16.71 mg/g) and lowest total sugar content was recorded in PM-5 (10.94 mg/g).The phenol content in genotype PM-5 (9.00 mg/g) was significantly higher than others whereas, the minimum phenol content was reported in IPM 306-6 (5.14 mg/g). The higher amount of total chlorophyll content found in genotype IPM 306-6 (3.22 mg/g) and lowest in PM-5 (1.85 mg/g). The significant and positive correlation was observed between M. vitrata larval population, pod damage and protein (r=0.954** and r=0.952**, respectively) and total sugar content (r=0.986** and r=0.986**, respectively) and total chlorophyll content (r=0.994** and r=0.993**, respectively) in immature pods, while, the significant and negative correlation was found between phenol (r= -0.916** and r= -0.919**, respectively).</div>

<div>Biochemical Factors Associated with Resistance to Spotted Pod Borer, Maruca vitrata (Fabricius) in Green Gram</div>

<div>Field experiments were carried out in pigeonpea during Kharif 2014 to Kharif 2017 for Maruca vitrata Fabricius management through farmscaping approach with 7 different border crops (5 leguminous crops; 2 non-leguminous crops) and a sole crop. The M. vitrata larval webbing per plant was lowest and per cent decrease in webbing/plant over sole crop was highest in sorghum (2.05 and 60.95) as border crop followed by pearl millet (3.29 and 37.39). The highest mean number of Coccinella septumpunctata per plant (0.77), Cheilomenes sexmaculata per plant (0.85/plant) and spiders (0.76/plant) was recorded from sorghum as border crop with pigeonpea. The highest percent increase in above said natural enemies over sole crop was also recorded from sorghum as border crop treatment (755.6, 844.4 and 660). The highest pigeonpea yield (730.72 kg/ha) and per cent yield gain (65.81%) was also recorded with sorghum treatment. Among 5 weather parameters tested, day length (1.53) and relative humidity (-0.12) were found to influence the M. vitrata population significantly and its incidence was recorded from 41st SMW to 47th SMW.</div>

<div>Seasonal Abundance of Spotted Pod Borer, Maruca vitrata Fabricius in Early Pigeonpea [Cajanus cajan (L.) Millsp.] and its Management through Farmscaping in Uttar Pradesh</div>

Background: The legume pod borer, Maruca vitrata, is recognized as serious insect pest on grain legumes and cause significant yield loss. Much research work has been carried out on management of M. vitrata with synthetic pesticides and biocides, there is paucity of knowledge on alternative non chemical methods to overcome this menace. Chemical signals from reproductive structures of host plants act as a key for lepidopteran phytophagous insects.&nbsp; 
 
Methods: Effects of volatiles from flowers and pods of different pulses such as pigeonpea, greengram, blackgram, cowpea and lablab on orientation pattern of M. vitrata larvae and adult moths and attractance behaviour of male moths to their females were investigated under laboratory conditions by using multi arm olfactometer and wide spaced basins.&nbsp; 
 
Result: One day old female moths showed significantly maximum orientation towards flowers of pigeonpea (42.7%) while elder age groups had the orientation ranging from 0.0 to 34.0 per cent on blackgram flowers and control (without host) respectively. The order of host preference of M. vitrata larvae observed as cowpea (32.2%) &gt;lablab (32.0%) &gt;pigeonpea (18.8%) &gt;greengram (9.0%) &gt;blackgram (4.8%) &gt;unsettled (3.0%). These results clearly showed the maximum preference of lablab by M. vitrata than other pulses tested. In an another experiment, one, two and three day old male moths had maximum orientation towards two day old females (31.3 to 40.0%) and this indicated more amount of sex pheromone emitted by female moths on two days after their emergence.

Orientation Behaviour of Legume Pod Borer, Maruca vitrata Fabricius (Lepidoptera: Crambidae) on Different Pulses

Background: Green gram also known as mung bean (Vigna radiata L.) which is a versatile and drought resistant pulse crop widely grown for its high nutritional value and play an vital role in crop rotation. It can be cultivated in the diverse climates and soil types which makes it important cash crop for farmers. 
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Methods: The experiment was conducted during the summer 2021 and 2022 at the Crop Research Centre of S.V.P. University of Agriculture and Technology to investigate the presence of M. vitrata on the various promising varieties and genotypes mungbean. Samples were collected from the immature plants. The experiment was conducted to estimate the biochemical constitutes viz. total soluble sugar, phenols, proteins and reduced sugar. 
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Result: Among all genotypes, Phenol content varied between 6.38 to 8.94. The maximum protein content was recorded in IPM-2-K-14-9(8.94 mg/g). Studies on the correlation between genotype&rsquo;s phenol content, M. vitrata damage (r=-0.712*) and number of larvae (r=-0.809*) had a significant negative correlation. The amount of protein content ranged between 11.09 to 18.95. KM-2328 (11.09 mg/g) had less amount of protein. The protein content with the number of larvae (r=0.581*) had a significant positive correlation. The percentage of pod damage was connected with protein content (r=0.550*) followed a similar pattern and had the significantly positive correlation. Sugar content of various genotypes varied between 10.52 to 19.76 mg/g. The maximum sugar content was recorded in SML-668 (19.76 mg/g) followed by the KM-2241 (19.47 mg/g), IPM-302-2 (19.01 mg/g), T-44 (18.42 mg/g) and K-851 (17.66 mg/g). The estimation range of reducing sugar content was 6.76 to 14.39 mg/g. The maximum reduced sugar was estimated in KM-2241(14.39 mg/g) and MH 421 (6.76 mg/g) had less amount of reducing sugar. The sugar was positively correlated with number of larvae and damage percentage done by M. vitrata.

Impact of Biochemical Constitute Responsible for Resistance against Maruca vitrata (Fabricius) in Different Genotypes of Mungbean

<div>Background: Maruca vitrata is an economically important cryptic insect pest in pigeonpea. Caterpillar, the damaging stage hides in the webs thus escapes the contact with insecticides thus making an effective insecticide also ineffective. Hence, the role of some tall statured intercrops in the manipulation of pigeonpea crop environment for reducing the incidence of this webbing caterpillar was studied.&nbsp; 
 
Methods: Studies were conducted at NPRC, Vamban, Pudukottai dt., Tamil Nadu to study the effect of different intercrops in reducing the incidence of Maruca vitrata. During kharif 2016-17 and 2017-18, M. vitrata incidence was compared among the intercropping systems (pigeonpea with pearlmillet, sorghum and maize in 1:6 ratio) and sole pigeonpea crop. IPM modules were formulated in which botanical spray (NSKE 5% at bud initiation stage) and spray of recommended insecticide (indoxacarb 15.8 EC-0.7 ml/lt at flowering and 15 days later) were integrated with intercropping practice and tested for efficacy against this borer pest.&nbsp; 
 
Result: Intercropping of pigeonpea with pearlmillet was effective in managing the spotted pod borer. Coccinellids and spiders were more in intercropped pigeonpea than the sole pigeonpea crop. Synchronized flowering times of short duration pigeonpea and intercrops would have facilitated the transfer of natural enemies from intercrops to pigeonpea and this may be the one of the reasons for the lower insect population. IPM module I (pigeonpea intercropped with pearlmillet, NSKE and indoxacarb sprays) was effective in reducing the spotted pod borer damage. In IPM module I, yield of 770 kg/ha was obtained as against 550 kg/ha in sole pigeonpea crop. Among the IPM modules, high B:C ratio of 1:1.66 was recorded with IPM module I.</div>

​​Habitat Manipulation: An Important Component of IPM in the Management of Webbing Caterpillar, Maruca vitrata (Geyer) in Pigeonpea

<div>Background: Legume pod borer, Maruca vitrata (Fabricius), infests the Dolichos bean throughout the cropping season. However, there is no information on the seasonal abundance of M. vitrata over different seasons on Dolichos bean, which is an essential tool for forecasting and developing integrated pest management strategies.&nbsp; 
 
Methods: The seasonal abundance of M. vitrata on Dolichos bean were studied during three consecutive cropping seasons of 2019 Summer, Kharif and Rabi. The larval population in flowers and pods and the number of larval webbings and weather parameters were recorded and subjected to correlation and multiple linear regression analysis. 
 
Result: The overall larval abundance was observed to be higher in flowers than in pods. The highest larval abundance in flowers and pods was 14.60 and 13.40 during the 48th and 50th standard meteorological week (SMW) of Rabi 2019 respectively, which corresponds to 8 to 10 weeks after sowing (WAS) in flowers and 10 to 12 WAS in the case of pods. The number of larval webbings was higher, with 18.76 during the 49th SMW of Rabi 2019. The maximum temperature had a significant negative correlation with the larval abundance in flowers (r= -0.570), pods (r= -0.523) and the number of active webbings (r= -0.477). At the same time, the regression coefficient shows that rainfall had a significant negative influence on the larval abundance in pods (B= -1.26).</div>

Influence of Weather Parameters on the Seasonal Abundance of Legume Pod Borer Maruca vitrata (Crambidae: Lepidoptera) on Dolichos Bean (Lablab purpureus var. typicus)

<div>Background: Cowpea [Vigna unguiculata (L.) Walp.] is an important legume crop known for its nutritional value. However, the cultivation of this crop is greatly hampered by a destructive pest, a spotted pod borer (Maruca vitrata Fab.). Keeping the caustic nature of the pest in view, the present study was undertaken. 
 
Methods: Field evaluation of thirty cowpea genotypes was carried out by raising cowpea plants in an open field. Observations on the M. vitrata incidence were recorded at three days&rsquo; intervals starting from the development of the first buds to the end of flowering. Based on the level of infestation of buds, flowers and pods, the cowpea genotypes were categorised into four groups viz., resistant, moderately resistant, susceptible and highly susceptible. 
 
Results: Results of the study revealed a significant variation between the genotypes in terms of total damage (0.21 to 48.46%). Genotype IC 2918 recorded remarkably low damaged (0.12%) and was on par with Palakkadan thandan payar, Hridya, EC 300039, EC 101216, EC 98668, IC 39945, IC 52110, IC 39922 and IC 39916. The genotype Bhagyalaxmi recorded the highest damage (48.46%) followed by the variety Lola (30.04%). Flower buds were more susceptible to M. vitrata and suffered severe damage as compared to flowers and pods. Conversely, genotypes EC 98668 and IC 39922 were free from bud damage. Genotypes EC 300039, EC 98668, IC 52110, IC 39945, IC 2918 and IC 39922 recorded no flower damage and Palakkadan thandan payar, IC 39945, IC 2918 and IC 39947 recorded no pod damage.&nbsp;</div>

Screening of Cowpea Genotypes for Field Resistance to the Spotted Pod Borer (Maruca vitrata)

Legume pod borer, Maruca vitrata (Geyer) is one of the major constraints in increasing the production and productivity of grain legumes in the tropics. Keeping in view of the importance of this pest, present studies were carried out with the association of different morpho-chemical traits with resistance/susceptibility to M. vitrata at the Pulses Research Station, SDAU, S.K. Nagar. Some of the characters like flower colour, pod angle, protein, flavonoid, tannin and phenols were found to be associated with M. vitrata &nbsp;attack on cowpea genotypes. The pod damage by M. vitrata on different cowpea genotypes in the field ranged from 10.22 to 19.98%. High phenol content in pods (428.63mg/100g) and (326.33mg/100g) found responsible for the resistance of GC 5 and GC 0815, respectively and high flavonoid concentration in pods (484.08mg/100g) and (458.81mg/100g) in GC 5 and GC 0815 respectively were responsible for resistance. Based on these results, GC 5 and GC 0815 were categorized as moderately resistant. This paper discusses the physico-chemical traits associated with resistance to M. vitrata in cowpea variety/genotypes.&nbsp;

Morphological and bio-chemical factors associated with resistance to&nbsp;Maruca vitrata (testulalis) &nbsp;(Geyer) in cowpea

<div style="text-align: justify;">The acute and persistent toxicity experiments was conducted in the Insectary of Agricultural College and Research Institute (AC&amp;RI), Maduari, Tamil Nadu Agricultural University. Two field experiments were conducted at farmer&rsquo;s field at Jadhi Goundanpatti, Attur Block, Dindigul district, Tamil Nadu. The incidence of M. vitrata (Geyer) has been increasing for the last few years and the larvae bore inside the flower buds, flowers and the green pods and cause upto 40-70 per cent damage. A new biological insecticide molecule, spinetoram 12 SC was evaluated for acute toxicity on laboratory reared M. vitrata population, and persistence on pigeonpea leaves at laboratory conditions; and effect on M. vitrata on pigeonpea at field conditions during 2012-13 and 2013-2014 seasons. Acute toxicity studies revealed that LC50&lsquo;s of spinetoram on third instar larvae after 24, 48 and 72 hours after treatment were 4.30, 1.95 and 1.46 ppm respectively. In persistence studies, Persistence was upto 11 DAT for spinetoram 12 SC 27 g a.i./ha, spinosad 45 SC 78 g, emamectin benzoate 5 SG at 11 g a.i./ha, and monocrotophos 36 SL at 500 g; and 14 DAT for spinetoram 12 SC 36 and 45 g a.i./ha. There was a reduction in the mortality of M. vitrata larvae as the time increased and there was no mortality at 21 DAT. Results indicated that spinetoram 12 SC was significantly effective at 36 and 45 g a.i./ha when sprayed thrice at 15 days interval and minimized the incidence of leaf feeder, M. vitrata on pigeonpea plants.&nbsp;</div>

Assessing Pigeonpea Genotypes for Resistance against Maruca vitrata Fabricius and its Sustainable Management through Biorationals

Biochemical Factors Associated with Resistance to Spotted Pod Borer, Maruca vitrata (Fabricius) in Green Gram

Seasonal Abundance of Spotted Pod Borer, Maruca vitrata Fabricius in Early Pigeonpea [Cajanus cajan (L.) Millsp.] and its Management through Farmscaping in Uttar Pradesh

Orientation Behaviour of Legume Pod Borer, Maruca vitrata Fabricius (Lepidoptera: Crambidae) on Different Pulses

Impact of Biochemical Constitute Responsible for Resistance against Maruca vitrata (Fabricius) in Different Genotypes of Mungbean

Habitat Manipulation: An Important Component of IPM in the Management of Webbing Caterpillar, Maruca vitrata (Geyer) in Pigeonpea

Influence of Weather Parameters on the Seasonal Abundance of Legume Pod Borer Maruca vitrata (Crambidae: Lepidoptera) on Dolichos Bean (Lablab purpureus var. typicus)

Screening of Cowpea Genotypes for Field Resistance to the Spotted Pod Borer (Maruca vitrata)

Morphological and bio-chemical factors associated with resistance to Maruca vitrata (testulalis) (Geyer) in cowpea

Field evaluation of spinetoram 12 SC against Maruca vitrata on pigeonpea