AbstractGroundnut is an important oilseed crop, and its productivity is often constrained by soil-borne diseases, among which collar rot is a major threat, particularly during the early crop growth stages. Limited information on the seasonal prevalence of collar rot and its relationship with prevailing weather parameters hampers timely disease management under field conditions. Therefore, a field survey was undertaken at different locations during Kharif 2023 to assess the incidence and temporal dynamics of collar rot disease in groundnut. The results revealed that collar rot disease initiated 20–25 d after sowing during the 25th Standard Meteorological Week (SMW) with a minimum disease incidence of 0.33 per cent. Disease intensity increased progressively and reached its peak (18.66 %) during the last week of July, after which a gradual decline was observed, reaching 0.33 per cent by the 37th SMW. Correlation analysis indicated a negative but non-significant association between disease intensity and temperature, whereas a positive and significant correlation was observed with relative humidity. The study concluded that collar rot incidence in groundnut is strongly influenced by seasonal weather conditions, particularly humidity, and is most severe during the early growth stages of the crop. Understanding the disease onset and peak period will aid in timely implementation of preventive and management strategies, thereby minimizing yield losses in groundnut-growing areas.
Tetarwal et al. (Wed,) studied this question.