Effect of Transplanting Method and Gypsum Rate on Yield and Yield Contributing Characters of Boro Rice in Saline Zone of Bangladesh

Abstract

Salinity intrusion causes problems in the coastal areas of Bangladesh. Climate change creates hazards like cyclone, sea level rise, and storm surge have been increasing the salinity problem in many folds. The coastal region covers about 20% of the country; from where cultivable land more than 30%. Agricultural land uses in these areas are very poor, because of high content of salinity in Rabi season. Already, 830,000 million hectares of land already identified as affected by soil salinity. A field experiment was carried out at saline prone area at Binerpota, Satkhira under natural salinity condition during Rabi season 2017-2018. The experiment was carried out with rice variety Binadhan-10.This variety was evaluated under four transplanting methods i.e., M0: Control (No Slope/flat land), M1: Ridge and furrow (each furrow 30 cm wide accommodating 3 lines transplanting), M2: Ridge and furrow (each furrow 60 cm wide accommodating 5 lines transplanting) and four levels of gypsum with control G0: control, G1: 75 kg ha-1, G2: 150 kg ha-1 as basal and G3: 150 kg ha-1(75 kg ha-1 as basal +75 kg ha-1 42 DAT). The experiment was laid out in a split plot design with three replications. The unit plot size was 3 m x 4 m. The recommended fertilizer doses applied for the experiment were 80 kg N ha-1, 15 kg P ha-1, 50 kg K ha-1. Nitrogen, phosphorus, potassium, sulphur and zinc were supplied from urea, TSP, MoP, gypsum and zinc sulphate monohydrate respectively while urea was applied in three equal splits. Application of gypsum had significant effect on plant height, number of effective tiller m-2, length of panicle, total number of spikelets panicle-1, thousand grain weight, number of filled spikelets panicle-1, grain yield straw yield. It seems that the crop responded to the application of gypsum. Overall results suggest that an application of gypsum The highest grain yield (7.7 t ha-1) was produced in ridge and furrow method where gypsum rate was 150 kg ha-1 (75 kg ha-1  as basal + 75kg ha-1 at weeks after transplanting followed by (7.4 t ha-1) basal application of 150 kg ha-1 gypsum along with N, P, K, Zn and Boron might be necessary to ensure satisfactory yield of rice in saline prone area under natural salinity condition.