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Bihar Agricultural University, Sabour

Bihar Agricultural University, Sabour established on 5th August, 2010 is a basic and strategic institution supporting more than 500 researchers and educationist towards imparting education at graduate and post graduate level, conducting basic, strategic, applied and adaptive research activities, ensuring effective transfer of technologies and capacity building of farmers and extension personnel. The university has 6 colleges (5 Agriculture and 1 Horticulture) and 12 research stations spread in 3 agro-ecological zones of Bihar. The University also has 21 KVKS established in 20 of the 25 districts falling under the jurisdiction of the University. The degree programmes of the university and its colleges have been accredited by ICAR in 2015-16. The university is also an ISO 9000:2008 certified organisation with International standard operating protocols for maintaining highest standards in teaching, research, extension and training.VisionThe Bihar Agricultural University was established with the objective of improving quality of life of people of state especially famers constituting more than two third of the population. Having set ultimate goal of benefitting society at large, the university intends to achieve it by imparting word-class need based agricultural education, research, extension and public service.

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Subject: Entomology × Author: Krishna, Hari ×
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    ThesisItemOpen Access
    Studies on major lepidopteran pests of mango and their management
    (Department of Entomology, BAU, Sabour, 2023) Krishna, Hari; Ray, S.N.
    Mango (Mangifera indica L.) belongs to the family Anacardiaceae. It is known as king of fruits and considered as “National fruit of India” due to its flavour, taste, nutritious value, religious and therapeutic significance. It is widely cultivated in the tropical and subtropical region in the world. Among lepidopteran insect pests of mango, mango leaf webber and fruit borers have become major threats in last few decades in Bihar. The present investigation entitled ‘Studies on major lepidopteran pests of mango and their management’ was conducted in the year 2019-20 and 2020-21 at AICRP mango orchard of Bihar Agricultural University, Sabour. Screening of cultivars, seasonal incidence of mango leaf webber, biophysical and biochemical parameters and management against mango leaf webber and mango fruit borers were carried out on mango cultivars. The mean of two consecutive years regarding screening of cultivars against mango leaf webber suggested that the number of webbed leaves per tree in Baramasia had significantly highest infestation level where as Alphonso recorded second highest infestation which was at par with Fernandin. Regarding the other cultivars, infestation in Dashehari was at par with Bombay, Mulgoa, Bangalora, Bombay Green, Kesar and SB Chausa whereas infestation level in Amrapali was at par with Bangalora, Bombay Green, Gaurjeet, Mulgoa and Prabhashankar. The cultivar Langra was found to be free from the infestation. With respect to direction preference (East, West, North and South), the mango leaf webber preferred the tree canopy of South direction followed by the West and the East direction. Therefore, the study identified the cultivar Langra as resistant to leaf webber whereas Dashehari was found as most susceptible cultivar to this pest. The present study revealed that the cultivar Mahmood Bahar and Prabhashanker were free from the infestation by red banded mango caterpillar during both the studied years. Significantly highest infested cultivar was recorded as Langra (15.90) followed by Zardalu (12.84), Keshar (11.93), Dashehari (13.05) and SB Chausa (10.23). Therefore, the present finding of Langra as highly susceptible cultivar to the RBMC where as Mahmood Bahar and Prabhashanker were free from the fruit borers. The mango leaf webber was found to be highly active (with more than 10 webs/tree) during the July to December. During rest of the periods, relatively lower activity of the pest was there with less than 1 web/tree. There were no active webs from the 2nd fortnight of February to 2nd fortnight of May. Infestation levels of mango leaf webber were different in the cultivars with different tree canopy type. Therefore, probably, the tree canopy type also played a crucial role in having variation in the level of pest infestation. Among the different canopy types (TC1 to TC7), TC3 was least preferred with mean infestation ranging from 0 to 0.61. Cultivars under this category were Prabhashankar (0), Mahmood Bahar (0.03) and Baneshan (0.61). Significant and negative correlation (r = -0.51**) of RBMC was found with peel thickness at fruit tip and significant and positive correlation (r = 45*) was found with seed length of fruits. Rest of the parameters like length of fruits, width of fruits, and width of stone/seed and thickness of mezocarp at fruit tip were not having any significant correlation. It was pertinent to notice that the highly infested cultivar Langra had 0.76 mm peel thickness in contrary to cultivar Prabhashanker (one of the least preferred cultivars) where the peel thickness was 0.86 mm at the fruit tip. The present investigation inferred that the total phenol content and mango leaf webber infestation had significantly negative correlation (r = -0.69) as presented. Significantly higher tannin contents were found in the cultivars namely, Prabhashanker, Baneshan, Mahmood Bahar, Langra and Gourjeet with the values of 17.33, 17.22, 16.67, 16.33 and 15.67 mg/g, respectively in comparison to the cultivars like Baramasia (9.00), Fernandin (9.67), Mulgoa (10.78), Kesar (11.45) and Himsagar (12.11). The formerly mentioned cultivars were among the least preferred whereas the later cultivars were among the most preferred cultivars. This parameter also had significantly negative correlation (r = -0.70) with the leaf webber infestation. The biochemical parameters such as phenol content (mg/g), tannin content (mg/g), reducing sugar (%), total sugar (%) and TSS (%), all measured separately in pulp and seed suggested that correlation coefficient values against RBMC infestation was significantly and negatively correlated with the phenol content in pulp (r = -0.56**) and seed (r = -0.42*). Against mango leaf webber, among the test insecticides, Lambda cyhalothrin 2.5 EC @ 1 ml/litre was found to be significantly superior over the other treatments containing least number of active webs per tree (along with highest percent reduction over control) followed by Indoxacarb 14.5 SC @ 0.5 ml/l of water. Against mango fruit borer complex, Chlorantraniliprole 18.5 % SC @ 0.2 ml/litre was found as the best molecule followed by Emamectin benzoate 5 SG @ 0.2 g/litre and Flubendiamide 20 % WG @ 0.3 g/litre.