Impact of Climate variability on recent and future status of lepidopterous insects of Pigeonpea at Banaskantha region of Gujarat (India)

Pigeonpea (Cajanus cajan) is grown across varied agro climatic zones and Gujarat contributes 9.6% of 3.75 million hectares (mha) in India. Information and communication technology (ICT) based pest surveillance of lepidopterous insect dynamics in relation to climate change during kharif (2011–16) revealed non significance on Grapholita critica (Meyr.) and Maruca vitrata (Fab.) and significant impact on H. armigera in pigeonpea at Banaskantha region of Gujarat. Besides positive effect of significantly increasing Rainfall (RF) and Maximum temperature (MaxT) and decreasing Minimum Temperature (MinT) had shown significant positive and negative impacts on Helicoverpa armigera. Seasonal dynamics across preceding and successive years followed the order of 2011 > 2015 > 2012 > 2013 > 2014 > 2016, 2012 > 2011 & 2013 > 2014 > 2015 & 2016 and 2011 > 2012, 2013 & 2015 > 2014 > 2016 for H. armigera, G. critica and M. vitrata, respectively. Future scenario of lepidopterous insects for 2020, 2050 and 2080 with changing climate using representative concentration pathway 4.5 for MaxT, MinT and RF had shown significant negative associations but for non-significance of MaxT in 2050, projecting reduced population of Helicoverpa during the whole of current century. Use of crop, climate and pest/disease dynamics and their management data provide ample and immediate scope of understanding effects of climate change and implement adaptive IPM strategies.