Seasonal incidence of insect pests and natural enemies of okra (Abelmoschus esculentus L. Moench) in relation to weather parameters during kharif 2025

Introduction

Okra (Abelmoschus esculentus L. Moench), commonly known as bhindi or lady's finger, is an economically important vegetable crop of the family Malvaceae, valued for its nutrient rich tender fruits and wide adaptability to tropical and sub-tropical climates. In India, okra is grown extensively during the kharif and summer seasons due to its wide adaptability, short duration and high economic return. India is the world's leading producer, contributing over 60 per cent of global output, with the crop occupies an area of about 5.55lakh hectares with an annual production of approximately 73.08lakh metric tonnes and a productivity of 13.14metric tonnes per hectare during 2024-25. Maharashtra alone accounting for about 13,990 hectares, producing nearly 1, 75, 440metric tonnes annually with a productivity of 12.54metric tonnes per hectare under the crop (Anonymous, 2025a; Anonymous, 2025b) [1,2] . Despite the availability of improved cultivars and agronomic packages, okra productivity remains constrained by a complex of more than seventy insect, mite and nematode species that attack the crop from the seedling stage to harvest. Among these, the sucking pest complex comprising leafhopper (Amrasca biguttula biguttula Ishida), aphid (Aphis gossypii Glover) and whitefly (Bemisia tabaci Gennadius), together with the shoot and fruit borer (Earias vittella Fabricius), are considered the most economically damaging (Ounis et al., 2024) [3] . Population build-up of these pests is strongly governed by prevailing weather conditions, particularly temperature, relative humidity and rainfall, which influence the timing, magnitude and duration of pest outbreaks (Potai et al., 2018; Soni et al., 2025) [4,5] . An accurate understanding of seasonal population trends and their weather correlates is, therefore, a prerequisite for developing weather-based forecasting models and for the timely and judicious deployment of management interventions, including need-based use of biorational products.

Materials and Methods

Experimental site and crop

The field experiment was conducted during Kharif 2025 at the Instructional Farm of Krishi Vigyan Kendra, Dhule (424 004), Maharashtra. Okra seed of the variety 'Hybrid Radhika' was sown by dibbling on 17 July 2025 at a spacing of 30 cm × 15 cm.

Seasonal incidence plot

For recording seasonal incidence, without any plant protection measures. Five plants were selected and tagged at random from plot, avoiding border rows and weekly observations were recorded of tagged plants.

Recording of observations

The population of leafhopper, aphid and whitefly was recorded on three leaves (one each from the top, middle and bottom canopy) per plant at weekly intervals from the tagged plants. The population of the predatory ladybird beetle (Coccinella spp.) was recorded on a whole-plant basis from the same tagged plants at weekly intervals. Infestation by shoot and fruit borer was assessed at each of the eleven fruit pickings by separating healthy and infested fruits and computing per cent fruit infestation on both number and weight bases at the weekly interval. Fruit infestation by the shoot and fruit borer (E. vittella) was evaluated weekly from picking initiation to crop harvest. Corresponding meteorological data (maximum and minimum temperature, morning and evening relative humidity and rainfall) for each Standard Meteorological Week (SMW) were obtained from the Agronomy Section, Government College of Agriculture, Dhule.

Results and discussion

Leafhoppers, Amrasca biguttula biguttula Ishida

During Kharif 2025 season, the leafhoppers population first appeared during the 30 th SMW 0.60 leafhoppers per three leaves per plant and increased steadily to reach a peak of 8.80 leafhoppers per three leaves per plant during the 37 th SMW. Thereafter, the population remained fairly high (5.20 to 7.80 leafhoppers/3 leaves/plant) up to the 44 th SMW, before declining sharply to 1.40 leafhoppers per three leaves per plant by the last week of October. These trends are in close agreement with Mahmood et al. (1990) [6] , Patni (2000) [7] , Potai et al. (2018) [4] , Thara et al. (2019) [8] , Bisen et al. (2020) [9] , Gupta et al. (2024) [10] and Soni et al. (2025) [5] , all of whom reported peak leafhopper activity around the 36 th to 39 th SMW on okra.

Aphids, Aphis gossypii Glover

Aphids population ranged from 2.80 to 18.20 aphids per three leaves per plant during the season, with initial appearance during the 30 th SMW and a peak of 18.20 aphids per three leaves per plant during the 37 th SMW, followed by a plateau at high density (13.00 to 15.80 aphids/3 leaves/plant) until crop termination. Similar peak periods were reported by Thara et al. (2019) [8] , Bisen et al. (2020) [9] and Sonawane et al. (2021) [11] , while Soni et al. (2025) [5] recorded a slightly delayed peak at the 39 th SMW.

Whitefly, Bemisia tabaci Gennadius

During Kharif 2025 season, the whiteflies infestation commenced during the 31 st SMW (0.20 whiteflies /3 leaves/plant) and increased to a maximum of 8.00 whiteflies per three leaves per plant during the 37 th SMW, before gradually declining. Comparable peak periods (35 th to 38 th SMW) have been reported by Yadav et al. (2013) [12] , Potai et al. (2018) [4] , Bisen et al. (2020) [9] and Soni et al. (2025) [5] .

Predatory ladybird beetle, Coccinella spp

During Kharif 2025 season, the ladybird beetle population appeared alongside the sucking pests from the 30 th SMW (0.60 ladybird beetle /plant) and reached its peak (4.00 ladybird beetle /plant) during the 37 th SMW, closely tracking the peak availability of its aphid and jassid prey. This close synchrony between predator and prey populations corroborates the findings of Gaikwad et al. (2020) [13] ; Bisen et al and is consistent with the general pattern of coccinellid build-up reported for okra agro-ecosystems.

Okra shoot and fruit borer, Earias vittella Fabricius

During Kharif 2025 season, the fruit borer damage commenced later in the season, during the 38 th SMW, with 8.16 per cent infestation on number basis and 10.86 per cent on weight basis. Infestation increased progressively thereafter, reaching a maximum of 24.67 per cent (number basis) and 25.37 per cent (weight basis) during the 44 th SMW, coinciding with the reproductive and late-fruiting phase of the crop. This late-season build-up pattern is in agreement with Vastav et al. (2019) [14] , Chaudhary et al. (2024) [15] and Sharma et al. (2025) [16] .

Correlation of pest and predator populations with weather parameters

Correlation analysis (Table 2) revealed that maximum temperature had a consistently negative but non-significant association with leafhopper, aphid, whitefly and ladybird beetle populations, while showing a weak positive, non-significant relationship with shoot and fruit borer infestation. Minimum temperature was significantly and negatively correlated with aphid (r = -0.419) and whitefly (r = -0.508) populations and showed a highly significant positive correlation with fruit borer infestation on number basis (r = 0.710**) and a highly significant negative correlation on weight basis (r = -0.694**).

Morning relative humidity exerted a significant positive influence on leafhopper (r = 0.412*), aphid (r = 0.435*) and ladybird beetle (r = 0.428*) populations, whereas its association with whitefly and fruit borer was positive but not significant. Evening relative humidity and rainfall showed, in general, weak and non-significant associations with all the pests and the predator studied. These findings broadly agree with Ratanpara et al. (1994) [17] , Anitha (2007) [18] , Sindhu et al. (2020) [19] , Bisen et al. (2020) [9] and Gupta et al. (1998) [20] , who similarly reported a dominant role of temperature and morning relative humidity in shaping the seasonal abundance of sucking pests and fruit borer on okra, with rainfall playing a comparatively minor role.

Conclusion

The sucking pest complex of okra leafhopper, aphid and whitefly along with the predatory ladybird beetle, appeared during the 30 th to 31 st SMW and attained peak populations synchronously during the 37 th SMW, indicating a strong predator-prey relationship. Shoot and fruit borer infestation, in contrast, was a late-season phenomenon, commencing in the 38 th SMW and peaking in the 44 th SMW. Minimum temperature and morning relative humidity emerged as the key weather drivers of pest and predator abundance, while rainfall exerted little influence. These results can inform the timing of monitoring and biorational spray schedules, with sucking-pest management best initiated by the last week of July/first week of August and fruitborer management from mid-September onward.

Acknowledgement

AcknowledgementWe are grateful to the Department of Entomology and the Agronomy Section, Government College of Agriculture, Dhule and to Krishi Vigyan Kendra, Dhule, for providing the experimental facilities and meteorological data used in this study.

References

1. Anonymous. Annual reports: First advance estimates. Ministry of Agriculture and Farmer's Welfare, Government of India; 2025.
2. Anonymous. Food and Agriculture Organization Statistical Database. Food and Agriculture Organization of the United Nations. 2025.
3. Ounis S, Turóczi G, Kiss J. Arthropod pests, nematodes, and microbial pathogens of okra (Abelmoschus esculentus) and their management: A review. Agronomy. 2024;14(12):2841.
4. Potai A, Chandrakar G. Studies on seasonal incidence of major insect pests and its natural enemies on okra and correlation with weather parameters. International Journal of Current Microbiology and Applied Sciences. 2018;6:204-210.
5. Soni S, Halder J, Chandra U, Singh AP. Influence of meteorological parameters on the seasonal abundance of sucking pests of okra (Abelmoschus esculentus L. Moench). Plant Science Today. 2025;12(1):1-5.
6. Mahmood T, Khokhar KM, Banaras M, Ashraf M. Effect of environmental factor on the density of leafhopper Amrasca devastans (Distant) on okra. Tropical Pest Management. 1990;36:282-284.
7. Patni SK. Effect of date of sowing and eco-friendly insecticides on the incidence and management of major insect pests of okra (Abelmoschus esculentus Moench). Thesis, Rajasthan Agricultural University, Bikaner. 2000.
8. Thara KT, Sharanabasappa, Narasa Reddy G, Girish BR. Seasonal incidence of sucking insect pests on okra agro-ecosystem. Journal of Pharmacognosy and Phytochemistry. 2019;8(1):2568-2571.
9. Bisen R, Singh D, Mishra P. Population dynamics of major insect pests and their natural enemies on okra (Abelmoschus esculentus L.) cv. Akola Bahar. Journal of Entomology and Zoology Studies. 2020;8(5):1520-1525.
10. Gupta SK, Yadav AK, Maheshwari S, Maurya PK, Kumar P. Population dynamics of major insect pests of okra in relation to weather parameters. Plant Archives. 2024;24(1):304-308.
11. Sonawane ST, Patil BV, Suradkar AL, Shelar DR. Population dynamics of sucking insect pests of okra. Journal of Entomology and Zoology Studies. 2021;9(2):1356-1358.
12. Yadav K, Singh RP. Seasonal incidence of insect pests of okra. Plant Archives. 2013;22(2):37-40.
13. Gaikwad BB, Bhosle BB, Sapkal SD. Seasonal incidence of natural enemies of insect pests on okra. Journal of Entomology and Zoology Studies. 2020;8(3):365-368.
14. Vastav ASS, Yadav P. Study on the seasonal incidence of shoot and fruit borer Earias vittella (Fab.) of okra [Abelmoschus esculentus (L.) Moench] and its correlation with weather parameters. International Journal of Current Microbiology and Applied Science. 2019;8(9):1953-1957.
15. Chaudhary A, Kumar R, Singh P, Yadav S. Seasonal incidence of shoot and fruit borer, Earias vittella (Fabricius), on okra in relation to weather parameters. The Pharma Innovation Journal. 2024;13(8):452-456.
16. Sharma AK, Kumar L, Seervi S, Sanjay M. Seasonal incidence of shoot and fruit borer [Earias vittella (Fab.)] on okra [Abelmoschus esculentus (L.)] in relation to abiotic factors. International Journal of Plant & Soil Science. 2025;37(1):393399.
17. Ratanpara AM, Shekh JR, Patel, Patel NM. Effect of weather parameters on brinjal leafhopper Amrasca biguttula biguttula (Ishida). Gujarat Agriculture Journal. 1994;19(2):39-43.
18. Anitha KR. Seasonal incidence and management of sucking pest of okra. M.Sc. (Agri.) Thesis, University of Agricultural Sciences, Dharwad, Karnataka, India. 2007.
19. Sindhu, Kalkal D, Rolania K, Kumar D, Kumari P, Kumar G. Incidence of sucking insect-pests of okra and their correlation with abiotic factors. Journal of Entomology and Zoology Studies. 2020;8(6):1636-1641.
20. Moench]. Journal of Research, BAU. 1998;10(1):12-15.
21. Aarwe R, Pachori R, Sharma AK, Thakur AS, Mandloi R. Impact of weather factors on the incidence of major insect pests of okra (Abelmoschus esculentus Moench). International Journal of Agricultural Science. 2016;8(3):981-983.
22. Badotiya SK, Meena BS, Singh RN, Sharma P. Seasonal incidence of sucking pests of okra (Abelmoschus esculentus L.). The Pharma Innovation Journal. 2023;12(3):1643-1645.
23. Dhandge SR, Bangale SA, Vaja AS, Virani VR. Seasonal incidence of sucking pest of okra and its relationship with weather parameters in summer season. International Journal of Current Microbiology and Applied Sciences. 2018;7(11):2697-2704.
24. Purohit D, Ameta OP, Sarangdevot SS. Seasonal incidence of major insect pests of cotton and their natural enemies. Pestology. 2006;30(12):24-29.
25. Sapkal SD, Mehendale SK, Shinde BD, Sanap PB, Chavan SS. Seasonal incidence of major sucking pests on okra. The Pharma Innovation Journal. 2022;SP-11(3):68-72.
26. Singh Y, Jha A, Verma S, Mishra VK, Singh SS. Population dynamics of sucking insect pests and its natural enemies on okra agro-ecosystem in Chitrakout region. African Journal of Agricultural Research. 2013;8(28):3814-3819.
27. Swamy KRM. Advances in okra production technology. Vegetable Science Review. 2023;8:22-31.