Climate Change-Related Crop Damage: A Significant Obstacle to Onion Farming in Kalwan Tehsil of Nashik District (MH): A Geospatial Analysis

Abstract Onions are an important horticultural crop cultivated worldwide for their extensive culinary use and as a spice, making them a vital component in food preparation. India ranks as the second-largest producer of onions globally; however, its yield per hectare remains lower compared to many other countries. Maharashtra is a leading state in India's onion production, contributing approximately 25% of the nation's total output. To investigate the reasons behind low onion productivity, a study was conducted to identify the challenges faced by farmers. Data were gathered from 100 farmers, with 10 participants selected from each of 10 villages in Kalwan tehsil. The results highlighted that irregular rainfall posed the most significant challenge, as reported by 74 farmers. This issue was particularly impactful during the harvest period of kharif onions and the preparation of rabi onion nurseries. In 2010, the monsoon arrived a month late and was followed by continuous rainfall until November. Unseasonal rainfall ranging from 200 to 300 mm in October and November severely damaged onion crops at various growth stages. Heavy rains in November caused substantial losses, affecting 30–40% of kharif onions ready for harvest, 15–20% of late kharif onions sown in September–October, and 20–25% of rabi onion nurseries. Additionally, the prevalence of anthracnose disease, particularly in kharif crops grown on flat beds, was exacerbated by water stagnation. Leaf damage caused by Colletotrichum and soil-borne diseases like bulb rot further hindered bulb development. To address these challenges, widespread adoption of techniques developed by the Directorate of Onion and Garlic Research (DOGR) is crucial. Recommended practices include the use of drip or sprinkler irrigation systems and the transplantation of seedlings on raised beds using the broad bed and furrow method, which can significantly improve onion productivity and reduce crop losses.