Varietal diversity of Sri Lankan traditional rice based on sensitivity to temperature and photoperiod at vegetative stage

Abstract

Photoperiod and temperature are two important environmental factors affecting vegetative growth and yield of rice. The varietal diversity based on the response to temperature and photoperiod during vegetative growth was determined in a core collection of 40 Sri Lankan traditional rice accessions (SLTRA) and 2 improved and 2 wild rice types in terms of days were imposed during 2 trials of high temperature (HT) and low temperature (LT) at under. Average DFL of the collection while photoperiod alone affected 1 accession. Average PHs by photoperiod or temperature. Temperature alone affected 12 accessions and photoperiod alone affected 2 accessions. Both photoperiod and temperature affected 4 accessions. In the SLTRA and improved rice were differentiated into 2 clusters at accessions of the same variety together. The differential varietal response to photoperiod and temperature in SLTRA would be useful in breeding for climate change adaptations after further experiments Oryza sativa

Reproductive Development and Yield Components of Bario Sederhana Rice in Response to Photoperiod

“…It has been reported that traditional rice cultivars from tropical regions are photoperiod sensitive and require between 160-170 days to mature (Vergara & Chang,1985;Viraktamath, 2013;Nandini, 2020;Khotasena et al, 2022). Most of the studies on photoperiodism of traditional rice in the tropics are from Cambodia (Makara et al, 2001;Tsubo et al, 2009;Uch et al, 2023), Thailand (Cha-um & Kirdmanee, 2007;Boling et al, 2011;Sujariya et al, 2023), and Sri Lanka (Mapalana, 2017;Padukkage et al, 2017;Rathnathunga et al, 2019). The geographical locations of these countries are within 7.9 °N-15.9 °N latitude, thus experiencing different changes in day length throughout the year.…”