Silicon status in soil and its effect on growth and yield of rice under the system of rice intensification and continuous flooding in Mkindo Irrigation Scheme, Morogoro, Tanzania

Silicon (Si) improves physical, chemical and biological properties of soil, enhances growth and rice yield. Hence, Si deficiency in the soil may lead to decline in rice yields. A study was undertaken to assess Si status in soils and its relation to growth and yield parameters of rice plant grown under the system of rice intensification (SRI) and continuous flooding regime in Mkindo Irrigation Scheme, Morogoro, Tanzania. A randomized complete block design (RCBD) with two treatments replicated three times was employed for the experiment. The treatments were two water application regimes (T1 and T2). T1 was alternate wetting and drying using SRI technology and T2 was continuous flooding. Rice variety SARO 5 (TXD 306) was used as a test crop. The experiment was conducted for two consecutive seasons from October 2019 to January 2020 and from March 2020 to June 2020. The objectives of the study were to assess the Si status in soils of the experimental site and to examine growth (in terms of plant height, number of tillers, number of productive tillers and number of panicles per hill) and grain yield in relation to soil Si status. Results showed that the soils of the study area had sufficient amount of available Si content (235.5 mg kg-1). Plots under SRI technology recorded higher plant height (147 cm), number of tillers per hill (54), number of productive tillers per hill (46), number of panicles per hill (31) and grain yield (8 tons ha-1). On the other hand plots under continuous flooding gave lower plant height (129 cm), number of tillers per hill (27), number of productive tillers per hill (22), number of panicles per hill (27) and grain yield (3 tons ha-1). It was thus concluded that, SRI enhanced higher uptake of soil Si which in turn improved significantly crop growth and rice yield