Effect of weather parameters on growth and development of Spodoptera frugiperda (J. E. Smith) in maize
Loading...
Date
2022
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Punjab Agricultural University
Abstract
The studies on the effect of weather parameters on growth and development of Spodoptera frugiperda (J.E. Smith) in maize were conducted on PMH 10 hybrid under laboratory conditions at five alternating temperature viz., 18:07, 24:12, 28:17, 32:22 and 36:27°C. The different developmental stages of S. frugiperda were influenced by temperature. The duration of different developmental stages viz., incubation, larva, pupa, and adult reduced with increase in temperature combinations of 18:7, 24:12, 28:17, 32:22 and 36:27oC. Maximum per cent hatchability (94.66%) was recorded at 36:22oC whereas no eggs hatched at 18:07oC. The larval survival was maximum (88%) at 36:27oC and minimum (66%) at 24:12°C. The larval duration was longer (29.50±0.24 days) at 24:12oC. It was significantly shorter (11.98±0.25 days) at 36:27°C. The minimum pupal survival of 68 per cent was recorded at 24:12oC. It was significantly more (96%) at 32:22°C. Pupal period was significantly longer (24.7±0.13 days) at 24:12oC and shorter (8.8±0.09 days) at 36:27°C. Overall, total life cycle of S. frugiperda took longer 68.06±0.49 days at 24:12°C and shorter duration of 29.38±0.65 days at 36:27°C. Maximum adult emergence of 80.64 per cent was recorded at 32:22°C while it was minimum (44.88%) at 24:12°C. The maximum male to female sex ratio of 1:1.80 was recorded at 36:27°C whereas minimum ratio of 1:1.27 was observed at 28:17°C. Fecundity increased significantly with increase in temperature being maximum (925.64 eggs/female) at 36:27°C and minimum (719.72 eggs/female) at 24:12°C. The adult longevity was maximum (male: 8.66±0.07; female: 9.46±0.04 days) at 24:12°C whereas lowest (male: 6.06±0.05; female: 6.82±0.05 days) at 36:27°C, respectively. The thermal constant for egg, larval, pupal and adult stages was found to be 45.45, 333.33, 166.67 and 125.00 Degree Days (DD), respectively totalling to 670.45 DD while, the lower developmental threshold was found to be 12.59, 12.33, 12.67 and 10.50oC for the respective stages. The dimensions of all the developmental stages (egg, larva, pupa and adult) of S. frugiperda were recorded to be increased with increase in test temperature combinations. Population growth parameters viz., net reproductive rate (R0), mean generation time (Tc), intrinsic rate of increase (rm), finite rate of increase (λ) and doubling time (DT) were influenced significantly by temperature. Among various life table parameters, highest net reproductive rate of 393.61±0.61 females/ female was observed at 32:22oC, whereas mean length of generation and doubling time was longest at 24:12oC. The innate capacity for increase and finite rate of increase was recorded highest at 36:27oC. The biology of S. frugiperda studied at different combinations of alternating temperatures of 24:12 and 32:22oC and carbon dioxide (CO2) levels of 375 ppm and 450 ppm revealed temperature as the major factor influencing the biology. As the temperature increased, the duration of growth stages viz., egg, larval, pupal and adult stages decreased and fecundity increased and same trend was also observed with increase in CO2 levels.
Description
Keywords
Citation
Pukhraj Singh (2022). Effect of weather parameters on growth and development of Spodoptera frugiperda (J. E. Smith) in maize (Unpublished M.Sc. thesis). Punjab Agricultural University, Ludhiana, Punjab, India.