Abstract

Rice paddy cultivation in Senegal is subject to climatic fluctuations that affect its vegetative development. Although climatic conditions are a concern, we hypothesized that the new rice paddy ISRIZ would be better adapted to these fluctuations and would allow double cropping. We studied the vegetative behavior according to the date and mode sowing under low temperatures. An experiment was carried out in a split-split plot design with sowings staggered every three weeks (18 dates), and two sowing modes (Broadcast, transplanting). Data collected included plant height, number of tillers, 50% flowering, 80% maturity. The results showed that the sowing date and method had significant effects on the morphology of the varieties. These effects were exacerbated by low temperatures, resulting in a lengthening of the cycle of the varieties. Some varieties performed well with flowering cycles of less than 100 days and are adapted to double cropping. The best planting period during the hot dry season is between February and March, while in winter, planting between July and August is recommended. In the cold, the practice of transplanting is better adapted. This study identified new varieties that could be adapted to the practice of double cropping in a context of climatic variability.

Key words: Irrigated rice, sowing dates, low temperatures, double cropping.