A Farmer’s Approach to Detecting Photoperiod Sensitivity in Rice (Oryza sativa ssp. indica) Landraces

Most indigenous rice landraces are sensitive to photoperiod during short day seasons, and this sensitivity is more pronounced in indica than japonica landraces. Attempts identify (PPS) cultivars based on the life history stages of plant, several models indices phenology length have not been precise, some cases yield counterfactual inferences. Following empirical method traditional Asian farmers, author has developed a robust index, sowing flowering dates large number grown different seasons from 2020 2023, contradistinguish PPS insensitive cultivars. Unlike other sensitivity, index does require presumed duration plant but relies only days till cultivar sown consistently