S Ahmed

Integrated approaches for controlling purple blotch of onion for true seed production in Faridpur of Bangladesh

An experiment was conducted during the Rabi season of 2014–2015 at the farmer’s field of Pearpur, Faridpur Sadar, Faridpur under the supervision of On-Farm Research Division (OFRD), Bangladesh Agricultural Research Institute (BARI), Faridpur to investigate the effective control method of purple blotch of onion during seed production and to develop ecofriendly and cost minimizing approaches for controlling purple blotch. The experiment was conducted using eight treatments viz., T1 = Combination of Iprodione and Mancozeb with Metalaxyl 4 times spray @ 2 g L−1 water each, T2 = Iprodione + Fenamidone with Mancozeb + Propineb + Mancozeb one time alternative spray each @ 2 g L−1 water for 4 times, T3 = Combination of Iprodione and Mancozeb with Metalaxyl 2 times spray @ 2 g L−1 water each + Trichoderma harzianum one time spray @ 50 ml L−1 water + Sanitation (25% removal of infected leaves at 77 DAP), T4 = Trichoderma harzianum two times spray @ 50 ml L−1 water + Combination of Iprodione and Mancozeb with Metalaxyl 1 time spray @ 2 g L−1 water each + Sanitation, T5 = Trichoderma harzianum compost used during final land preparation @ 50 g m−2 plot + T3, T6 = Trichoderma harzianum compost used during final land preparation + Trichoderma harzianum 3 times spray @ 50 ml L−1 water + Sanitation, T7 = Difenoconazole 2 times @ 1 ml L−1 water + combination of Iprodione and Mancozeb with Metalaxyl 2 times spray @ 2 g L−1 water each and T8 = Control. Successful control of purple blotch of onion was achieved by spraying fungicide (chemical plus bio) in treatment T5 followed by T3 and T4 treatment. The highest seed yield was 580 kg ha−1 obtained from the treatment T5 in onion seed crop. The highest benefit: cost ratio (3.92) was calculated from T5 treatment and the lowest from T8 (2.78).

Response of capsicum to boron and zinc application in terrace soils of Gazipur, Bangladesh

A field experiment was conducted at vegetables research field of Horticulture Research Centre, Gazipur in terrace soils under Madhupur Tract (AEZ 28) during rabi seasons of 2009-10, 2010-11and 2011-12 to determine the optimum dose of boron and zinc for yield maximization of capsicum. There were sixteen treatment combinations comprising four levels each of B (0, 1, 2 and 3 kg ha -1 ) and Zn (0, 2, 3 and 4 kg ha -1 ) along with blanket dose of N 150 P 65 K 120 S 20 kg ha -1 including cow dung 10 t ha -1 were used. The experiment was laid out in RCBD factorial with three replications. Results revealed that maximum mean number of fruits per plant (11.1), the highest fruit length (9.29 cm) and diameter (7.34 cm), maximum individual weight of fruits (122 g) were recorded from the combination treatment of B 2.0 Zn 3.0 and the highest mean yield (31.8 t ha -1 ) was also recorded from the same treatment. The 84.8% yield increase over control (B 0 Zn 0 ) due to combined application of B 2.0 Zn 3.0 kg ha -1 . The combined application of zinc and boron were observed superior to their single application. Therefore, the combination of B 2.0 Zn 3.0 treatment may be considered as suitable dose for capsicum cultivation in terrace soils of Bangladesh. Bangladesh J. Agril. Res. 42(1): 43-52, March 2017