A field experiment was conducted at saline prone area, Suparishata, Sodor, Sathkira under natural salinity condition during in 2017-18, was carried out with two varieties namely, V1=Binadhan10, V2=BRRIdhan67 and four levels of silicon with control S0: 0 kg ha-1, S1: 5 kg ha-1, S2: 10 kg ha-1 and S3: 15 kg ha-1. The experiment was laid out in a split plot design with three replications. The unit plot size was 3m x 4m. The treatments were randomly distributed to the plots within a block. The bunds around individual plots were sufficiently strong to control water movement between the plots. A drain of 1meter wide provided for watering around the whole experimental plot and between the blocks.
Seedlings rising Seedlings were raised in well prepared wet seed bed at the sub-station Satkhira farms. Before sowing, seeds were immersed in water for 24 hours and then they were taken out and kept in jute sacks in dark condition for 48 hours. Seedling nurseries for each variety were prepared by pudding the soil. The sprouted seeds were sown on a well prepared wet nursery bed in 1 January, 2018. No manuring and fertilization was done but water and pest management practices were followed in order to raise healthy seedlings.
Land preparation The land preparation was started one month prior to transplant of the seedlings. The land was thoroughly prepared with the help of a power tiller. Subsequently, the land was sufficiently irrigated and ploughed and cross ploughed three times with country plough followed by laddering to have a good tilth. All kinds of stubble and residues of previous crop were removed from the field. After uniform leveling, the experimental plots were laid out according to the requirement of the treatment.
Fertilization and manuring The plots of Boro rice were fertilized with N, P, K, S, Zn at the recommended by the rate of respectively according to the recommendation of BARC (2005). The whole amount at triple super phosphate, muriatic of potash silicon, gypsum and zinc sulphate were applied to the soil at the time of final land preparation. Urea was applied in three equal splits. One split of urea was applied with other fertilizers as basal dose and the other two splits were applied 21 and 45 DAT. The seed bed was wet by application of water both in the morning and evening on the previous day before uprooting the seedling. Thirty days old seedlings were uprooted carefully from the seedling nursery for transplanting in the experimental plots. Only selected healthy seedlings were translated in the experimental plots in 1 February 2018 in 20 cm apart line maintaining a distance of 15cm from hill to hill with three seedlings hill-1 proper care was taken during the growing period of the crop.
Intercultural operation Intercultural operating was done in order to ensure and to maintain the normal growth of the plant as and when needed. After one week of transplanting dead seedling were replaced carefully by transplanting fresh seedlings from the same source. The experiment plots were infested with some common weeds which were removed twice by hand weeding. After transplanting six irrigations were needed to maintain 5-6 cm standing water in each plot. Finally, the field was drained out 7 days before harvest. Observations were regularly made and the field looked nice with normal green plants.
Harvesting and data collection The crops were harvested on 27 April, 2018 with sickle at full maturity. The maturity of crops was determined when some 70% of the seeds became attain their character’s color. Grain and straw yields plot were recorded after threshing by a pedal thresher winnowing and drying in the sun properly including the grains and straws of the sample plants. The weight of grains was adjusted to 12% moisture content. Grain and straw yield were them converted to tha-1. From the 10 randomly harvested hills, the following data were recorded, plant height, number of total tillers hill-1, number of effective tillers hill-1 , number of non-effective tillers hill-1, number of grain panicle-1, number of unfilled spikelet’s panicle-1,1000 grain weight, Grain yield (tha-1), Straw yield (tha-1) Biological yield (tha-1), harvest index (%).
Data processing and analysis Data recorded for different parameters were subjected to analysis of variance (ANOVA) and the treatment means were compared using the least significant different test.