Coastal Karnataka is facing a 29% rainfall deficit, raising concerns for agricultural productivity.Experts warn that this deficit could worsen whitefly infestations in coconut plantations, as higher temperatures and reduced moisture create ideal conditions for the pests.In districts like Chikkamagaluru and Hassan, black-headed caterpillars are also expected to thrive due to erratic weather patterns.Arecanut farmers face another challenge with increased nut shedding caused by dry spells, adding to existing issues like yellow leaf disease.Paddy cultivation remains stagnant despite rains in early July, with only 6.86% of the targeted 10,000 hectares sown in Dakshina Kannada.Environmental activists highlight risks of human-animal conflict as water sources dwindle, impacting hydel power generation.The Karnataka Horticulture Department has been advised to take preventive measures against pests and diseases affecting plantations.