Optimizing Plant Spacing under the Systems of Rice Intensification (SRI)

Optimum plant spacing is among key agronomic parameters that influence crop growth performance and crop yield. A study was conducted to investigate the optimum rice transplanting spacing under the Systems of Rice Intensification (SRI) practice in Tanzania. The study composed of five treatments of rice transplanting spacing namely 1) 15 cm × 15 cm (T1); 2) 20 cm × 20 cm (T2); 3) 25 cm × 25 cm (T3); 4) 30 cm × 30 cm (T4); and 5) 35 cm × 35 cm (T5). The experiment was set in a Randomized Complete Block Design (RCBD) and transplanted with uniform age of 12 days old seedlings in all treatments. The rice variety tested was TXD 306 Super SARO which was recommended by the Ministry of Agriculture for flooded rice in central and eastern Tanzania. Data was collected throughout the two growing seasons (Masika and Vuli) of 2013 and 2014. Data collected include biomass at vegetative, flowering and harvesting stages, total number of tillers per hill, number of productive tillers per hill, number of grains per panicle and rice grain yield at the end of the season. Data was analyzed using SAS software version 9.1. Results have shown that transplanting spacing of 25 cm × 25 cm, 30 cm × 30 cm and 35 cm × 35 cm has significantly performed better than rice transplanted at 15 cm × 15 cm and 20 cm × 20 cm. For the higher performing treatments, 25 cm × 25 cm has performed much higher than the rest. It is therefore recommended that for rice variety TXD 306 Super SARO under SRI practice in areas with soil conditions similar to Mkindo area in Morogoro Region, the optimum transplanting spacing that gives maximum yield is 25 × 25 cm.