~ 3002 ~ Journal of Pharmacognosy and Phytochemistry 2020; 9(5): 3002-3006 E-ISSN: 2278-4136 P-ISSN: 2349-8234 www.phytojournal.com JPP 2020; 9(5): 3002-3006 Received: 12-06-2020 Accepted: 18-07-2020 P Thilagam Assistant Professor, Tamil Nadu Agricultural University, Agricultural Research Station Virinjipuram, Vellore, Tamil Nadu, India D Dinakaran Professor and Head, Department of Plant Protection, Tamil Nadu Agricultural University, Agricultural College and Research Institute Vazhavachanur, Tiruvannamalai, Tamil Nadu, India A Gopikrishnan Assistant Professor, Tamil Nadu Agricultural University, Agricultural Research Station Virinjipuram Vellore, Tamil Nadu, India Corresponding Author: P Thilagam Assistant Professor, Tamil Nadu Agricultural University, Agricultural Research Station Virinjipuram, Vellore, Tamil Nadu, India Identification of resistant genotypes against major podborers and diseases in pigeonpea ( Cajanus cajan L.) P Thilagam, D Dinakaran and A Gopikrishnan Abstract An experiment was conducted to during Kharif, 2019 to identify the resistant genotypes towards major pod borers and diseases in pigeonpea. Observations on the larval population of Helicoverpa armigera (Hubner) at 50 per cent flowering stage ranged from 0.3 - 7.0 No.s / plant in all the pigeonpea genotypes tested with the lowest being obtained in Yelagiri local and the highest in ICP8840. The webcounts of Maruca vitrata (Geyer) ranged between 0.3-12.7 webs per plant. At the time of harvest, among the podborers, the pod damage caused due to Melanagromyza obtusa (Malloch) was comparatively high and recorded between 9.3-28.0 per cent. The pod damage caused by M.vitrata ranged from 1.3 – 30.5 per cent and H. armigera recorded 1.3-28.5 per cent. Out of seventy entries with ICP 8863 as check, sixty one entries were found to be highly susceptible, five entries were susceptible and three entries were moderately susceptible and AC9060 was moderately resistant to podborer complex. For sterility mosaic disease, fifteen entries were found to be susceptible expressing more than 30 per cent of infection. Thirty pigeonpea geonotypes expressed 10-30% infection with moderately resistance and twenty four were found to be resistant. Zero wilt incidence was recorded in twenty one entries and the remaining entries tested also exhibited only 1.8 to 6.9 per cent wilt incidence which confers their resistance to wilt. Keywords: Pigeonpea, screening, pod borer complex, wilt, sterility mosaic disease Introduction Pigeonpea, Cajanus cajan, L. is an important legume crop and is rich in protein source and ensures nutritional security to the country. The crop can be cultivated in areas of less rainfall due to its drought-resistant nature. The crop can also able to fix atmospheric nitrogen and enriches the soil and also can be interplanted with other short term crops for higher productiivty per land area and reduced risks associated with some crop failures (Dasbak et al., 2012) [2] . In India, Pigeonpea is grown in 4.42 million ha with an annual production of 2.89 million tonnes with 655 kg ha-1 of productivity. It is a predominant pulse crop in Vellore district next to groundnut, paddy and sugarcane. It is grown in an area of 13,584 ha which accounts for about 20% of Tamil Nadu state. Though the area under pigeonpea cultivation is more in this district, it is cultivated mainly under rainfed situation and many places it is grown as an intercrop in groundnut. There is a wide gap between potential and the actual yield obtained by the farmers. Among the various constraints, biotic constraints viz., insects and diseases are the major ones that threatens pigeonpea production. Though approximately 200 insect and mite pests attack pigeonpea, the economic loss by attacking the crop at flowering and pod development stages, pod borers viz., Spotted podborer, Maruca vitrata (Geyer), gram podborer, Helicoverpa armigera (Hubner) and podfly, Melanagromyza obtusa (Malloch) are the major insects determining the yield potential in pigeonpea crop (Saxena, 2012) [10] . Among the podborers, M. vitrata caused heavy losses in early, medium and late maturing genotypes (Shanower et al., 1999) [12] as the larvae feed by remaining inside the webbed mass of leaves, flowers and pods. This concealed feeding complicates the management of this pest as pesticides and natural enemies have difficulty in penetrating the shelter to reach the target (Sharma, 1998) [13] . Among the various diseases, wilt and sterility mosaic diseases (SMD) are the major constraints limiting the pigeonpea production. Wilt, Fusarium udum is a major soil-borne disease in almost all pigeonpea growing areas (Carlos Popelka et al., 2004) [1] . The pathogen enters the plant through roots, affect the vascular system and causes wilting within few days of entry. The loss in grain yield due to wilt disease depends on the stage of the crop at which the disease appears and loss is total if it occurs before pod formation (Kannaiayan and Nene, 1981 and Okiror, 2002) [4, 8] . SMD caused by by pigeonpea sterility mosaic virus (PPSMV) is the economically important viral diseases in India, causing an estimate annual loss of more than