A field experiment was conducted at the `Research Farm` of Regional Seed Production Office of Lal Teer Seed Limited, Dinajpur, Bangladesh during November 2008 to April 2009. The study was conducted to investigate the effect of bulb size and planting spacing on seed production of cultivar Taherpuri onion. Three bulb sizes [small (5±2g), medium (10±2g), and large (15±2g)] and four planting spacing [closest 25×15, closer 25×20, wider 30×15, and widest 30×20cm] was considered in this experiment. Number of flowering stalks, length of flowering stalks, number of umbels per plant, number seeded fruits, seed weight per umbel, 1000-seed weight and seed yield per hectare were measured to assess the onion seeds. The results revealed that the highest seed yield (776.67 kg) per hectare was obtained from the large bulb (15±2g) with the closest spacing of 25×15cm followed by small bulb size of same spacing. The maximum number of flowers per umbel (371.39), seed weight per umbel (0.80g) and 1000-seed weight (3.92g) were obtained from the largest bulb size (15±2g) with widest (30×20cm) planting spacing. Hence, large bulb size with closest plant spacing is suggested for onion seed production in northern part of Bangladesh. Bangladesh J. Agril. Res. 37(3): 405-414, September 2012 DOI: http://dx.doi.org/10.3329/bjar.v37i3.12084

The comparative growth and yield performances between two Mungbean (BARI Mung 6 and BARI Mung 5) varieties with foliar application of GA3 (0, 50, 100 and 150 ppm) were studied to find out the suitable variety and optimum level of GA3 application. The design of experiment followed was RCBD. Data on morpho-physiological characteristics were recorded at 15, 25, 35, 45and 55 days after sowing (DAS) and yield contributing parameters were recorded only at harvest stage. The results showed that application of GA3 @ 100 ppm produced better performance on morpho-physiological characters namely, plant height (56.59cm), number of leaves per plant (10.75), branches per plant (4.75), length of root (24.73cm), total dry matter weight (12.67g)which were recorded from the variety BARI mung 6 with the foliar application of GA3 @ 100 ppm. Yield contributing characters were also showed the highest performance in terms of number of pods per plant (23.40), pod length (6.67cm), number of seeds per pod (12.82), thousand seed weight (33.95 g), seed yield (7.53 g/plant and 1.92 t ha–1), and harvest index (35.36%) which were the highest with the application of 100 ppm GA3 in case of BARI Mung 6. Single and combined effects of treatments were found statistically significant. Between two varieties BARI Mung 6, among the treatments GA3 @ 100 ppm as foliar application and interaction effect of GA3 @ 100 ppm and BARI mung 6 showed the highest performance in respect of all growth and yield parameters. Progressive Agriculture 29 (3): 233-238, 2018

An incubation experiment was conducted at the Department of Soil Science, Patuakhali Science and Technology University during Rabi season 2015 to investigate the effects of different levels of salinity on germination and early seedling growth of maize. There were ten treatments consisting of different concentrations of salinity viz. 0, 20, 40, 80, 120, 160, 200, 240, 280 and 320 mM NaCl. The germination experiment was conducted in petri dish lined with a layer of cotton consisting ten ml of each test solution. Germination percentage gradually decreased with the increase of concentration of salt. Up to 80 mM concentration was found safe for maize seed germination. Salinity caused delay in germination.  Highest seedling height was found at 40 mM NaCl concentration (21.51 cm) and root length (23.61 cm) was found in 20 mM NaCl concentration. In 320 mM NaCl concentration roots were abnormal, deformed and twisted. The 0 to 80 mM NaCl concentration gave statistically similar shoot fresh weight. Compared to control treatment 20 mM NaCl concentration gave 0.55 % higher fresh weight and at 80 mM NaCl concentration shoot fresh weight reduced by only 6.9 %. The 80 mM NaCl concentration was found acceptable for germination and early seedling growth of maize.Progressive Agriculture 28 (1): 18-25, 2017

The most sensitive stages of Boro rice against the low temperature are agronomic panicle initiation (API), reduction division (RD) and flowering/anthesis. The critical low temperature is growth stage specific. The time and intensity of the critical low temperature during Boro season has a direct impact on the growth and yield of a crop. Therefore, it is necessary to understand the probability of the critical low temperature with respect to the growth stages to have a good planning for safe harvest. Long term weekly low temperature data have been used to estimate the probability of falling low temperature on those stages and the return period was computed. The growth durations of 1-and 30-November seeded Boro rice crop from 45-day-old seedling of BRRI dhan28 (short duration) and BRRI dhan29 (long duration) are considered to observe the probability. A Boro crop encountering critical low temperature is appeared to suffer from cool injury. The extent of cool injury depends on the nature and duration of low temperature and diurnal change of low (night) and high (day) temperature. The critical low temperature for a rice crop at API, RD and anthesis are 18, 19 and 22°C, respectively. Boro rice is grown between November and May. The low temperature occurs from October to early March. There is, therefore, the probability of low temperature occurrence from the crop establishment to the flowering stage is a great concern. The probability of experiencing stage-wise critical temperature approaches to 100% for early established and short duration crop. However, the late established and long duration crop has the probability little less than the early and short duration crop. In a study it has been observed that short duration BRRI dhan28 having 64.6% sterility to yield 2.5 t ha-1 and BRRI dhan29, 40.8% sterility to yield 6.5 t ha-1. The percentages of corresponding sterility for late established crops were 35.9 and 32.8%. Irrespective of growth duration, the yield is affected a little of the late established crop. Despite low temperature along with the reproductive phase, the late established crop is quite safe due to the parallel high (day) temperature (31-35°C). The high maximum temperature appears to play an important role through the alleviating effect of low temperature. But for early-established particularly short duration variety could not escape the low temperature at some of its sensitive growth stages as the high temperature appears to stay a several degree low (27-29°C) at that time. The low level of high temperature is appeared to drag down the low temperature to aggravate the growth and development of a crop. Therefore, not only the variation of high temperature of the day but also the variation of critical low temperature might have some role in alleviating effect of cool-injury. The periodic return of critical low temperature (10-15°C) during the reproductive stage may occur every year or every alternate year depending on the time across the cropping season and the region as well. Therefore, the critica...

The experiment was conducted at the field laboratory of the Patuakhali Science and Technology University, Patuakhali, Bangladesh during the period from November, 2011 to March 2012 under the tidal Floodplain region to find out optimum sowing time for the selected three cultivars (BARI Sharisha-15, BINA Sharisha-5 and BARI Sharisha-9). There were four sowing dates viz. 30 November, 15 December, 30 December and 15 January. Significant variations due to different sowing dates were observed in plant height, total dry matter, leaf area index, number of siliqua plant -1 , seeds silique -1 , 1000-grain weight, grain yield and HI. Results showed that the highest grain yield (1.73 t ha -1 ) was obtained from the first sowing (30 November) with BINA Sharisha-5 and it was significantly different from the yields of all other combination.