Tolerance of Five Upland Rice Cultivars at Various Levels of Drought Stress

The aim of this study was to determine the drought tolerance limit of five upland rice (Paddy Gogo) cultivars in the germination phase. This research was carried out at the Seed Science and Technology Laboratory, Faculty of Agriculture, University of Tadulako, Palu, Indonesia, from September to October 2020. This study was arranged using a completely randomized design (CRD) with a factorial design of 2 factors. The first factor was the cultivar consisting of five cultivars, i.e., Pau Tau Leru, Jahara, Uva Buya, Buncaili, and Kalendeng. The second factor was the Polyethylene Glycol (PEG) concentration which consisted of five levels, i.e., Without PEG, 10%, 20%, 30% and 40% PEG. There were 25 treatment combinations. Each treatment was repeated three times (75 experimental units). The results showed that Uva Buya and Jahara cultivars had a high tolerance for PEG which was characterized by the maximum growth potential, germination power above 85%, and germination time in less than 4 days with the treatment of 40% PEG concentration. Meanwhile, Pau Tau Leru, Buncaili, and Kalendeng cultivars were able to grow and germinate well up to 10% PEG concentration. Both Uva Buya and Jahara cultivars also had a longer and heavier plumule and radicle, and larger roots.