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Salinity is one of the most devastating abiotic stresses limiting crop production. Considering this issue, a pot experiment was conducted at Sher-e-Bangla Agricultural University, Dhaka, Bangladesh during the boro season (2017-2018) using two rice(Oryza sativa L.) varieties, namely BRRI dhan28 (salt sensitive) and BRRI dhan47 (salt tolerant),to assess the effects of varied salinity levels on the growth and the performance of the rice varieties under salt stress conditions. Four salinity treatments were used in this experiment, viz. control S0 (only freshwater), quarter-strength marine water S1 (three-parts freshwater and one-part marine water; 7.5 ds m−1), half-strength marine water S2 (half freshwater and half marine water; 15 ds m−1), and full-strength marine water S3 (only marine water; 30 ds m−1).These mixtures were used for irrigation purposes throughout the life cycle of the plants. Salt stress significantly decreased the plant height, relative water content (RWC) of leaves, number of effective tillers hill−1, number of filled grains panicle−1, 1000-grain weight, grain yield, straw yield, and biological yield of the rice. In both rice types, plant growth and yield were reduced as the salinity level increased. Grain yields decreased by 50, 90, and 100% in BRRI dhan28 when irrigated with quarter strength, half strength, and full-strength seawater, respectively, but decreased by 27, 50, and 72%, respectively, in BRRI dhan47. Similarly, other yield attributes had higher reductions in BRRI dhan28 under salt stress conditions than BRRI dhan47. However, irrigation with marine water in rice might lead to some straw yield but produced little to no grain.

Boron is an important micronutrient that enhances vegetative growth and yield of crops, like peanut. Light also plays an important role in pegging of peanut. There has been little information regarding the application of boron and light in peanut in Bangladesh. Therefore, a field experiment was conducted to study the response of boron and light on morph-physiology and pod yield of two peanut varieties. Treatments considered two peanut varieties,namely, Dhaka-1 and BARI Chinabadam-8, three levels of boron (B),namely, 0-kg B ha−1(B0), 1-kg B ha−1(B1), and 2-kg B ha−1(B2), and two levels of light,namely, normal day light (≈12 h light) and normal day light + 6 h extended red light at night (≈18 h light). Result revealed that days to first-last emergence and days to first-50% flowering took shorter times and vegetative growth, pods dry weight plant−1, pod yield, and germination were markedly increased with the application of boron. Vegetative growth and germinations were significantly increased in light, but the lowest leaf area, pods dry weight plant−1, and pod yield were found in light. Without germination, the highest vegetative growth, reproductive unit, and pod yield were observed from BARI Chinabadam-8. Days to first-last emergence, days to first-50% flowering, and number of branches plant−1were found linearly related to pod yield.

Rice production in the tidal floodplain of southern Bangladesh is constrained by uncontrolled water. In absence of high yielding varieties suitable for tidal floodplain, farmers grow low yielding indigenous cultivars of tall plant type. This paper reports the effect of agronomic management on the yield and yield components of an indigenous rice cultivar, Sadamota. The trial was conducted in 10 farmers' plots located widely apart in two upazila (sub-districts)-Jhalakati and Rajapur. 45 d and 60 d old seedlings were transplanted either in rows at 40 cm × 20 cm spacing or following farmers' traditional practice of random planting. Transplanting 60 d old seedlings produced 14% higher yield compared with 45 d old seedlings. Transplanting in rows also increased grain yield by 12%. The yield increase was associated with hill density, the number of effective tillers per hill and the number of spikelets per panicle.

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