Pest scenario of Helicoverpa armigera (Hub.) on pigeonpea during future climate change periods under RCP based projections in India

Abstract

Gram pod borer, Helicoverpa armigera (Hub.) is the major insect pest of pigeonpea and prediction of number of generations (no. of gen.) and generation time (gen. time) using growing degree days (GDD) approach during three future climate change periods viz., Near (NP), Distant (DP) and Far Distant (FDP) periods at eleven major pigeonpea growing locations of India was attempted. Multi-model ensemble of Maximum (Tmax) and Minimum (Tmin) temperature data of four Representative Concentration Pathways viz., RCP 2.6, 4.5, 6.0 and 8.5 of Coupled Model Inter comparison Project 5 (CMIP5) models was adopted here. The increase in projected Tmax and Tmin are significant during 3 climate change periods (CCPs) viz., the NP, DP and FDP over base line (BL) period under four RCP scenarios at all locations and would be higher (4.7–5.1 °C) in RCP 8.5 and in FDP. More number of annual (10–17) and seasonal (5–8) gens. are expected to occur with greater percent increase in FDP (8 to 38%) over base line followed by DP (7 to 22%) and NP (5to 10%) periods with shortened annual gen. time (4 to 27%) across 4 RCPs. The reduction of crop duration was substantial in short, medium and long duration pigeonpeas at all locations across 4 RCPs and 3 CCPs. The seasonal no.of gen. is expected to increase (5 to 35%) with shortened gen. time (4 to 26%) even with reduced crop duration across DP and FDP climate periods of 6.0 and 8.5 RCPs in LD pigeonpea. More no. of gen. of H. armigera with reduced gen. time are expected to occur at Ludhiana, Coimbatore, Mohanpur, Warangal and Akola locations over BL period in 4 RCPs when normal duration of pigeonpeas is considered. Geographical location (66 to 72%), climate period (11 to 19%), RCPs (5–7%) and their interaction (0.04–1%) is vital and together explained more than 90% of the total variation in future pest scenario. The findings indicate that the incidence of H. armigera would be higher on pigeonpea during ensuing CCPs in India under global warming context.

First record of Hadda beetle, Henosepilachna (Epilachna) vigintioctopunctata Fab. Coccinellidae: Coleopatra on Ashwagandha, Withania somnifera L. (Solanaceae) from Tamil Nadu, India

“…The number of generations of Helicoverpa armigera was predicted to increase with a decrease in their generation time under elevated temperatures (Srinivasa Rao et al, 2023). The adult longevity of Citrostichus phyllocnistoides and Cirrospilus ingenuus, when reared on citrus leaf miner, exhibited a significant decrease in response to elevated temperatures (Ullah et al, 2023).…”

Suitability of Satellite Imagery for Surveillance of Maize Ear Damage by Cotton Bollworm (Helicoverpa armigera) Larvae

“…The Carpathian Basin's climatic conditions are temperate, and this climate does not permit the continuous presence of the CBW in this region (although, it should be noted that overwintering is becoming more frequent here [7]). Temperature is the most significant factor determining the moth development rate [21,128], and the CBW in this region develops two to four generations, in contrast to the subtropical regions where the number of moth generations can reach more than ten [128]. For this reason, the extension of the method to the Mediterranean regions requires further investigation.…”

Climate Change and Invasive Insects in Forest Ecosystems - Recent Examples from Türkiye

“…Ithomiola butterfly species that do not die during winter because of the warmer climate are also significant as they lay eggs now in spring and the next generation occurs now in spring. Such species are the cotton bollworm [Helicoverpa armigera (Hübner, 1808)] and the silver Y moth [Autographa gamma (Linnaeus, 1758)] (Srinivasa Rao et al, 2023).…”