Abstract
Abstract
Background
The tomato fruit borer, Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae), is a serious insect pest owing to its polyphagous nature, migrating long distances, greater capacity to develop resistance against insecticides and persistence in cropping areas. The comparative evaluation of temperate, sub-tropical and tropical H. armigera NPV (HearNPV) isolates was carried out to determine the potential of local and exotic HearNPV isolates for the management of H. armigera in Kashmir, India, having a temperate climate.
Results
Mortality of 2nd instar H. armigera larvae with three different HearNPV isolates at different concentrations ranged between 13.40 and 73.25%, with significant differences between the concentrations in each isolate under laboratory conditions. The median lethal concentration (LC50) values of HearNPV-IND-K, HearNPV-IND-J, and HearNPV-IND-B isolates against 2nd instar H. armigera larvae were 4.62 × 103, 5.99 × 104, and 7.24 × 104 OBs/larva at 10th day post inoculation, with significant differences among the isolates. In time response bioassays, the cumulative mortality (%) caused by median lethal concentration (LC50) of HearNPV-IND-K, HearNPV-IND-J and HearNPV-IND-B isolates over a period of 10 days was 50.33, 49.00 and 49.00%, respectively. Their median survival time (ST50) values against 2nd instar H. armigera larvae were 8.10, 8.94 and 9.50 days, respectively, with significant differences among the isolates. The results revealed that the LC50 and ST50 values of HearNPV-IND K isolate were significantly lower than HearNPV-IND-J and HearNPV-IND-B isolates. The cumulative mortality of H. armigera larvae with HearNPV-IND-K, HearNPV-IND-J and HearNPV-IND-B isolates at different concentrations ranged between 22.00–68.32, 20.54–55.17, 11.66–44.33%, respectively, on tomato crop under field conditions. The highest mortality rate of 68.32% was observed at the local isolate (HearNPV-IND-K).
Conclusions
It’s concluded that the local isolate had the potential for the development of species-specific and environmentally safe biocontrol agent for organic farming and its incorporation into Integrated Pest Management program may reduce the use of chemical insecticides in Kashmir.
Publisher
Springer Science and Business Media LLC
Subject
Insect Science,Plant Science,Agronomy and Crop Science,Ecology
Reference27 articles.
1. Ali G, Abma-Henkens MH, Van der Werf W, Hemerik L, Vlak JM (2018) Genotype assembly, biological activity and adaptation of spatially separated isolates of Spodoptera litura nucleopolyhedrovirus. J Invertebr Pathol 153:20–29
2. Arora R, Sharma HC, Dreissche EV, Sharma KK (2005) Biological activity of lectins from grain legumes and garlic against the legume pod borer. Helicoverpa Armigera J SAT Agric Res 1(1):1–3
3. Arrizubieta M, Simon O, Williams T, Caballero P (2016) Determinant factors in the production of a co-occluded binary mixture of Helicoverpa armigera alphabaculovirus (HearNPV) genotypes with desirable insecticidal characteristics. PLoS ONE 11(10):e0164486
4. Black JL, Lorenz GM, Cato AJ, Bateman NR, Seiter NJ (2022) Efficacy of Helicoverpa Armigera nucleopolyhedrovirus on soybean for control of Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) in Arkansas Agriculture. Insects 13(1):91
5. Chitneni SK (2008) Development and evaluation of diagnostic tools for nucleopolyhedroviruses (NPVs) infecting major lepidopteran pests of legume crops in the Semi-Arid Tropics (Doctoral dissertation, Acharya Nagarjuna University)