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Solar drying is the common traditional method to preserve fruits by reducing its moisture content and the microorganisms’ activities, hence, slowing down the mold growth, which affect the quality of fruits. Operational cost of solar dryer can be cheaper but the drying time using solar dryer is usually longer than other drying techniques that use electricity due to the lower and inconsistent temperature within its drying chamber. In this work, bananas, papaya and pineapple were dried using an oven at temperatures of 65-85oC, and the results were compared with the outcomes of drying using a simple wood solar cabinet dryer, done in Kota Samarahan, Sarawak Malaysia. The drying profiles for the fruits dried in the oven were found to be quite similar, indicating the insignificant variation in the cell matrix structure of the fruits, and in addition, these results were supported by the small range of the estimated drying constants between 1.32 - 1.83 10-1 hr-1. Moreover, the results showed that the increase in the temperature of drying in the oven from 65 to 75oC did not change the drying time significantly, but the drying time was reduced significantly to 70% when the temperature was increased to 85oC. The fluctuation of temperature and air flow within the solar dryer between 27-34oC and 0.12 -1.52 m/s, respectively, slowed down the drying process, resulting to prolong of drying time. The drying time to reduce the moisture content from 80-60% for the solar drying was between 31 to 74 hours while for oven drying with temperatures of 65-85oC was between 1-5 hours.

In order to assess the effect of biofertilizer and weeding regimes and their interaction on the performance of bush bean (Phaseolus vulgarisL.), a field experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh following randomize complete block design (RCBD) with three replications during winter season, in 2017. The experiment consisted of five treatments of biofertilizer (B0= no biofertilizer, B1= 1.0 Kg biofertilizer ha-1, B2= 1.5 Kg biofertilizer ha-1, B3= 2.0 Kg biofertilizer ha-1, B4= 2.5 Kg biofertilizer ha-1) and four level of weeding W0= No weeding, W1= One weeding at 15 DAS, W2= Two weeding at 15 DAS and 30 DAS, W3= Three weeding at 15 DAS, 30 DAS and 45 DAS. Yield contributing characters were significantly influenced by biofertilizer and weeding regimes. In case of attributes affected by yield factor for biofertilizer the highest plant height, weight of seed plant-1, grain and stover yield in 1.5 Kg biofertilizer ha-1, number of seed plant-1in 1.0 Kg biofertilizer ha-1, weight of 1000 seeds in no biofertilizer and harvest index in 2.0 Kg biofertilizer ha-1treatments were observed. Considering yield attributes against weeding regimes, the highest plant height, grain yield, stover yield and harvest index in three weeding, weight of seeds plant-1and weight of 1000 seeds in two weeding were found. In case of interaction effect highest plant height in B2W3, weight of seeds plant-1in B4W2, weight of 1000 seeds in B1W3, grain yield in B3W3, stover yield in B3W3and harvest index in B0W3were observed. The results obtained in experiment indicate that there is ample scope to increase the yield of bush bean by applying proper dose of biofertilizer and management of weeding regimes.

The experiments were conducted at the Agronomy Field Laboratory, Agricultural University, Mymensingh in Bangladesh during December 2015 to April 2016 to investigate the effect of variety and plant spacing on yield attributes and yield of maize. The experiment comprised of five varietiesviz.,Khoi bhutta, BARI hybrid maize 7, BARI hybrid maize 9, C-1921, P-3396 and five plants spacingviz.,75 cm × 20 cm, 75 cm × 25 cm, 75 cm × 30 cm, 75 cm × 35 cm and 75 cm × 40 cm. The experiment was laid out in a randomized complete block design with three replications. Results revealed that variety and plant spacing had significant effect on the studied crop characters and yield. The highest plant height, highest number of leaves plant-1, longest cob, maximum diameter of cob, highest number of kernel cob-1, the highest 1000-grain weight, maximum grain yield and stover yield were observed in BARI hybrid maize 7. On the other hand, the shortest plant, lowest number of cob, diameter of cob, lowest number of grains cob-1, 1000-grain weight, grain yield and stover yield were observed in Khoi bhutta. The longest plant, highest cob, maximum diameter of cob, highest number of kernel cob-1the highest 1000-grain weight, maximum grain yield and stover yield was observed in the spacing of 75 cm × 25 cm. In contrast, the spacing of 75 cm × 30 cm produced the lowest values of the above mentioned plant parameters and also showed the lowest grain yield. In regard to interaction effect of variety and spacing, the highest plant height (232.67 cm), maximum number of cob plant-1(1.73), maximum diameter of cob (4.60 cm), highest number of kernel cob-1(34), maximum stover yield (12.38 t ha-1) were observed at the spacing of 75 cm × 25 cm with BARI hybrid maize 7 and resulting in the highest grain yield (9.04 t ha-1). The lowest values of the above parameters were recorded in the narrowest plant spacing of 75 cm × 35 cm with Khoi bhutta. Based on the experimental results, it may be concluded that maize (cv. BARI hybrid maize 7) can be cultivated with a spacing of 75 cm × 25 cm for appreciable grain yield.

The study was conducted during winter season (February-June) of 2016 at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh. Fourteen rice varieties namely, BRRI dhan28, BRRI dhan29, BRRI dhan47, BRRI dhan50, BRRI dhan55, BRRI dhan58, BRRI dhan59, BRRI dhan67, Binadhan-5, Binadhan-6, Binadhan-8, Binadhan-10, BRRI hybriddhan3 and Agrodhan14 were grown under weedy and weed- free conditions. Plots with no rice were also maintained to study the natural growth of weed in absence of rice. Primed rice seeds were dry seeded following 25 cm ×15 cm spacing with 5 seeds hill-1on non-puddled soil. Plots were surface irrigated as and when necessary to maintain aerobic condition (at around field capacity) up to heading stage followed by wet condition from heading to grain filling stage. The results revealed that rice varieties varied widely in yield performance and weed suppressive ability. Among varieties, BRRI dhan59 allowed the minimum weed growth (20.8 g m-2) while Binadhan-5 allowed the maximum weed growth (65.8 g m-2). Grain yield ranged from 2.2 t ha-1(BRRI dhan55) to 4.67 t ha-1(Binadhan-5) under weed-free condition and from 0.62 t ha-1(BRRI dhan55) to 2.48 t ha-1(BRRI dhan59) under weedy condition. Weed infected relative yield loss ranged from 40.1% to 78.2% among varieties. BRRI dhan59 incurred the least yield penalty (40.1%) while Binadhan-5 performed the best in terms of grain yield (4.67 t ha-1) but its weed inflicted relative yield loss was higher (76.4%) than any other variety with low yield potential. BRRI dhan59, on the other hand, appeared as the most weed competitive variety (only 40.1% relative yield loss) with yield of 4.19 t ha-1. Present study confirms that the varieties tested under study varied widely in terms of weed suppressive ability and yield performance. Considering both yield and weed competitiveness, BRRI dhan59 can be recommended for cultivation following modified aerobic system.