Integrating traditional knowledge and field monitoring to assess insect pest tolerance in indigenous rice varieties of Wayanad, Kerala

Abstract

The traditional rice varieties are a crucial part of ecological farming practices in Wayanad, Kerala. The present study combined traditional knowledge with field monitoring to assess the insect pest tolerance of 49 traditional rice varieties in seven panchayats of northern Wayanad, Kerala, for five wet seasons (June to October) from 2019 to 2023. The measurement of pest density and abundance, along with parasitism, was used to calculate a composite Pest Index for each rice variety (0-1; higher values indicate lower tolerance), while farmer perceptions and traditional measures such as leaf strength, aroma, and recovery characteristics were collected through interviews (n = 203). Random Forest analysis revealed that lodging, maturity days, and grain yield were useful predictors of pest incidence (AUC = 0.91; OOB ≈ 8%). While Jeerakasala, Mundon, and Gandhakasala were found to be highly susceptible to pests, Kanakam, Kayama, Kunjootti, Kunnumkulamban, and Marathondi were found to be most tolerant to insect pests. In addition to the significance of preserving pest-tolerant varieties for sustainable and low-input rice cultivation, the strong agreement between farmer perceptions and results confirms the validity of traditional ecological knowledge.