The experiments were carried out at the Regional Agricultural Research Station, Rahmatpur, Barisal during the rabi seasons of 2001-2002 and 2002-2003 to study the impact of different sulphur levels on bulb yield, storability and economic return of onion. Sulphur application had significant effect on yield components and bulb yield of onion. The highest bulb yields (19.75 and 19.88 t/ha) were obtained from sulphur levels between 60 and 75 kg/ha in two consecutive years. Both the cumulative weight and rotten loss were significantly influenced by sulphur fertilization. The maximum weight loss (40.78%) was recorded after 180 days of storage in S 60 kg/ha and the minimum (31.40%) was found in S45 kg/ha. The bulbs stored in bamboo platform were found in acceptable condition after 6 months of storage showing 31.40% of weight loss. The maximum rotten bulbs (63.75%) were observed in control treatment (without S) and the minimum rotten bulbs (37.04%) were observed in S45 kg/ha after 180 days of storage because application of sulphur enhanced the storability of onion bulbs. The highest (9146 %) marginal rate of return (MRR) with gross margin of Tk. 181844/ha was obtained from the sulphur level S 60 kg/ha.

Relative abundance of leaf and plant hoppers species regarding plant growth stages and temperature were studied in the rice variety BINA10 field at the research farm of Patuakhali Science and Technology University (PSTU) during October 2013 to April 2014. The percent relative abundance of leafhoppers was in the rank order of M. dorsalis> C. brevis> N. virescens> N. malayanus> N. cincticeps> N. nigropictus at seedling, early and maximum tillering stages while N. virescens> C. brevis> M. dorsalis> N. nigropictus> N. malayanus> N. cincticeps at reproductive stage. The percent relative abundance of planthoppers was in the rank order of N. nervosa> N. lugens> S. furcifera at seedling and reproductive stages while N. lugens> N. nervosa> S. furcifera at early tillering and N. nervosa> S. furcifera and N. lugens at maximum tillering stages. The abundance of all leafhopper species showed highly negative relationship with temperature. This relationship can be expressed by 81% (R2=0.806) for N. virescens, 80% (R2= 0.801) for N. nigropictus, 65% (R2=0.653) for N. cincticeps, 60% (R2=0.600) for C. brevis and 70% (R2=0.698) for M. dorsalis. Among three planthopper species, population of S. furcifera showed highly negative relationship with temperature and this relationship can be expressed by 71% (R2=0.707). The abundance of N. nervosa showed poor positive relationship with temperature. This relationship can be expressed by 3 % for N. nervosa (R2=0.030). N. lugens showed poor negative relationship with temperature and this relationship can be expressed by 31% (R2=0.310) for N. lugens.SAARC J. Agri., 16(1): 95-104 (2018)

A pot experiment was conducted to study the effects of sewage sludge and nitrogen fertilization on the growth, yield, nutrient and heavy metal uptake into rice straw (Oriza setiva L cv. BRRI dhan-36). There were five 5 treatments (T 0 , T 1 , T 2 , T 3 and T 4 ) consisting of 5 levels of sewage sludge (0, 60, 120, 200 and 300 t/ha) and 5 levels of nitrogen (280, 49, 35, 28 and 21 kg/ha). In the experiment the highest height of the rice plant (97.33 cm per plant) and number (55.00) of tillers per four plants were recorded with the treatment, 300 t/ha sewage sludge plus 21 kg/ha nitrogen. The length of spikelet was significantly high in all treatments compared to the treatment, 300 t/ha sewage sludge plus 21 kg/ha nitrogen. On the other hand, both the fresh and dry weight of rice straw was significantly high in the aforesaid treatment compared to the other treatments. The contents of N, K, Na, Ca, Mg, Fe, Cu, Zn and Pb in rice straw increased significantly with increasing sewage sludge levels and were observed high at the treatment, 300 t/ha sewage sludge plus 21 kg/ha nitrogen, but the amount of P and Mn uptake decreased significantly with increasing sewage sludge levels showing an antagonistic effect. Cr, Cd and Ni contents were below detectable level.

The response of mukhi kachu (Colocasia esculenta L.) cultivars (Bilashi and local variety) to inorganic (Urea 140 kg ha-1, TSP = 95 kg ha-1, MP= 145 kg ha-1 and Urea 150 kg ha-1, TSP= 100 kg ha-1, MP= 150 kg ha-1) and organic (Cowdung 5,000 kg ha-1, Mustard oil cake 100 kg ha-1 and Poultry dropping 8000 kg ha-1) fertilizers was determined at the farm of Patuakhali Science and Technology University, Bangladesh. Different levels of organic and inorganic fertilizers showed significant effect on number of cormels, dry weight of cormels and yield of the crop. Organic fertilizers produced significantly higher yields of mukhi kachu over the inorganic fertilizers. The variety Bilashi produced the highest yield (25.66 t ha-1) with the application of mustard oil cake.

An experiment was conducted to evaluate the effectiveness of five IPM packages in controlling flea beetles and thrips on mungbeans. The results showed that the lowest number of flea beetles (1.67/plot), the highest reduction in flea beetle population the over control (72.17%), the lowest leaf area damaged (3.33%) and the lowest percent reduction in damaged leaf area versus control (72.99%) was recorded from plots treated with Package 2 (Virtako 80WG @ 0.15 g/L water + white sticky trap). The lowest number of thrips populations (1.00/20flowers), the highest reduction in thrips population versus control(85.0%), the lowest number of damaged flowers (2.33/plant), and the highest reduction in infested flowers over control (79.44%)observed in plots treated with Package 1 (Bioneem plus 1% EC at the rate of 1 ml/L water + white sticky trap). There was a negative correlation between the numbers of flea beetles and thrips with total yield. A negative relationship was observed between flea beetle leaf area infestation and total yield, and between thrips flower infestation and total yield from different IPM packages. This study concluded that IPM package 2 was the most effective package for controlling flea beetles and IPM package 1 was good enough for controlling thrips in mungbeans. Jahangirnagar University J. Biol. Sci. 11(1 & 2): 81-91, 2022 (June & December)