Biological and Ontogenic Studies of Brinjal Shoot and Fruit Borer (Leucinodes orbonalis Guenée) under Controlled Laboratory Conditions
Priyanshi Kamal
Department of Entomology, College of Agriculture, Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya 224229, Uttar Pradesh, India.
Umesh Chandra *
Department of Entomology, College of Agriculture, Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya 224229, Uttar Pradesh, India.
Sameer Kumar Singh
Department of Entomology, College of Agriculture, Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya 224229, Uttar Pradesh, India.
Mohd Yahya
Department of Entomology, College of Agriculture, Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya 224229, Uttar Pradesh, India.
Kamal Ravi Sharma
Department of Entomology, College of Agriculture, Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya 224229, Uttar Pradesh, India.
Ankit Kumar
Department of Entomology, College of Agriculture, Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya 224229, Uttar Pradesh, India.
Ram Veer
Department of Entomology, College of Agriculture, Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya 224229, Uttar Pradesh, India.
*Author to whom correspondence should be addressed.
Abstract
The present study examined the biology, developmental duration, ontogenic characteristics and larval growth pattern of the brinjal shoot and fruit borer, Leucinodes orbonalis Guenée, on brinjal (Solanum melongena L.) under controlled laboratory conditions of 26 ± 1°C and 70 ± 5 per cent relative humidity. Freshly laid eggs were creamy white and became orange before hatching. The incubation period ranged from 4.00 to 6.00 days, with a mean duration of 5.00 ± 1.00 days. Fecundity ranged from 115.00 to 128.00 eggs per female, with a mean of 121.40 ± 6.51 eggs, while egg hatchability ranged from 64.46 to 73.04 per cent and averaged 68.44 ± 4.38 per cent. Larval development consisted of five instars and was completed within 10.00 to 14.00 days, with a mean duration of 12.00 ± 2.00 days. The pupal period ranged from 7.00 to 11.00 days and averaged 9.00 ± 2.00 days. The total life cycle ranged from 32.00 to 34.00 days in males and from 34.00 to 37.00 days in females. Females were larger and lived longer than males. Morphometric observations showed a progressive increase in larval length, breadth and head capsule width across successive instars. Mean head capsule width increased from 0.28 ± 0.02 mm in the first instar to 1.60 ± 0.03 mm in the fifth instar. Growth ratios of 1.59, 1.57, 1.53 and 1.48 supported Dyar’s law. Correlation analysis indicated strong positive associations among larval instars, larval dimensions and head capsule width. These findings provide baseline information for identifying vulnerable developmental stages and supporting stage-specific, environmentally sustainable integrated pest management strategies against this pest of brinjal.
Keywords: Brinjal, Solanum melongena, Leucinodes orbonalis, shoot and fruit borer, biological parameters, larval instars, morphometry, head capsule width, Dyar’s law, integrated pest management