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Background: Pigeon pea (Cajanus cajan, Mayer) is the member of Asian Cajanus crop and also reffered as Tur and Arhar and commonly grown in Kharif session in Indian subcontinent.). In India, around 250 known species of insect pests have been identified to affect pigeon pea crops at different growth stages. The leaf webber and leaf roller are notable insect pests that pose a significant threat to pigeonpea, particularly during its vegetative stage. The leaf webber and leaf roller, among various insect pests, are notably visible and pose a threat to pigeonpea. These insects target the pigeonpea plant during its vegetative stage. Specifically, the leaf webber, identified as Grapholita (Pammene) critica, Meyrick (Lepidoptera: Tortricidae), has been acknowledged as a significant constraint affecting pigeonpea production. The aim of this investigation is to assess the relationship between the incidence of leaf roller and leaf webber and various abiotic factors, including temperature, relative humidity, wind velocity and rainfall. Methods: The research, spanning Kharif 2021-22 and 2022-23, at Entomological Research Block in BUAT, Banda. It aimed to observe leaf roller and leaf webber incidence in pigeon pea alongside weather conditions. 'IPA-203' pigeon pea variety was manually sown in 200 m2 plots on July 12, 2021 (first year) and July 18, 2022 (second year). Standard agronomic practices were adhered to and no insecticides were used on the crop. Result: Over the two-year observation period, the larval population of G. critica on pigeon pea plants commenced during the 34th SMW, peaking at 4.90 larvae plant-1 in the 45th SMW. Simultaneously, C. soyella infestation initiated in the 34th SMW, steadily increasing until the 42nd SMW, reaching its peak larval count at 3.03. [ABSTRACT FROM AUTHOR]

The studies entitled "Population build-up and seasonal occurrence of pod bug Clavigralla gibbosa (Spinola) in long duration pigeon pea ecosystem in Bundelkhand region of Uttar Pradesh" was conducted at the Student Research Farm, BUAT, Banda, India during kharif 2021-22 and 2022-23. Seasonal occurrence of pod bug in pigeon pea exhibited that the peak population of pod bug (7.90/plant) at 10th standard meteorological week (SMW) during 2021-22 while during 2022-23 peak population of pod bug was recorded at 9th SMW (11.40/plant). The average population of C. gibbosa of both years was recorded during 9th SMW (9.38/plant). Correlation studies of the average number of pod bugs in both years and weather variables found that the morning relative humidity was negatively associated (r = -0.568), whereas evening relative humidity had a substantial negative correlation value (r = -0.665). The regression analysis found that maximum temperature, morning relative humidity, evening relative humidity, and wind velocity were the most influential factors on the occurrence of pod bug populations, influencing 16.3, 32.2, 44.2, and 20.7%, respectively. [ABSTRACT FROM AUTHOR]

The present study performed a three-dimensional numerical analysis on an adiabatic flat plate with forward injection holes for multi-zone film cooling. The cooling holes were divided into three-zone, and the cold air was supplied from cylindrical holes at a velocity ratio of 0.5 and 1.5 with 30° inclination to the primary flow. The effect of multi-zone arrangement in film cooling effectiveness is studied, and a comparison between two-zone and three-zone arrangement has been made. Results show that the three-zone arrangement helps achieve better film cooling effectiveness than the two-zone arrangement due to the uniform flow of coolant at a higher velocity ratio. It also reduces the mass flow rate of secondary flow by decreasing the number of cylindrical holes in the perforated plate. [ABSTRACT FROM AUTHOR]

In the present work, a three-dimensional numerical analysis of multi-hole film cooling on an adiabatic flat plate with combined backward and forward injection holes is carried out at varying velocity ratios from 0.5 to 2.5. The effect of three different multi-hole arrangements, square-diamond, long-diamond, and super-long-diamond with constant perforated percentage (3.27%), on film cooling performance is studied. Combining backward and forward injection holes help in achieving higher velocity boundary layer thickness in the multi-hole arrangement. It is observed that super-long-diamond arrangement provides the highest film cooling effectiveness than square-diamond and long-diamond arrangements and favours early development of coolant film layer. [ABSTRACT FROM AUTHOR]