Yield and Nutrition of Rice as Influenced by Pre-submergence and Amendments in a Highly Sodic Soil

A field experiment was designed to evaluate the effect of amendments viz, gypsum, pyrites, farmyard manure (FYM), and rice husk with two periods of duration of pre-submergence (0 and 30 days), prior to the transplanting of rice seedlings on soil properties, yield and chemical composition of the crop in a highly sodic soil (pH 10.6, ESP 94). Beneficial role of pre-submergence on grain yield was very much conspicuous over the treatments which had no prior flooding. This effect was more pronounced with FYM and rice husk as compared with gypsum and pyrites. Though gypsum and pyrites reduced the pH and exchangeable Na to a large extent and recorded higher yields than other treatments without pre-submergence, FYM was found equally effective on crop yield and nutrient composition. Submergence enhanced the uptake of P, K, Co, Mg, Fe, Mn, Zn, and Cu by the crop, except K, Mg and Cu in grain but Na uptake was decreased. Use of FYM and rice husk brought about marked improvement in Fe and Mn concentration in the crop. A period of 30-day pre-submergence can thus be considered as an important requirement to obtain better yield of rice when calcareous sodic soils are to be reclaimed by using amendments.