M N Yousuf
Spices Research Centre, Bangladesh Agricultural Research Institute Gazipur-1701
M M Kamal
Spices Research Centre, Bangladesh Agricultural Research Institute Gazipur-1701
M M Akand
Spices Research Centre, Bangladesh Agricultural Research Institute Gazipur-1701
N Akther
Spices Research Centre, Bangladesh Agricultural Research Institute Gazipur-1701
N Mohammad
Agricultural Statistics and Information & Communication Technology Division, Bangladesh Agricultural Research Institute Gazipur-1701
Onion, Seed production, Irrigation
Experimental field of Regional Spices Research Centre, BARI, Gazipur
Crop-Soil-Water Management
Irrigation scheduling
The experiment was conducted at the experimental field of Regional Spices Research Centre, Gazipur during 2011-2012. The soil was silty clay loam with field capacity and bulk density, 29% and 1.44 gm/cc, respectively. The soil of experimental field was nutrient deficient and slightly alkaline in nature (Table 1). Onion variety "BARI piaz-1" was used to study the effect of irrigation levels on onion seed production. The technique of bulb to seed method was used for this experiment. The experiment was laid out in a randomized complete block design with three replications. Well decomposed cowdung (10 t/ha) and recommended dose of fertilizer (150-100-180 kg/ha NP- K) in the form of urea, triple super phosphate and mural of potash was applied to grow the crop. In addition to N-P-K, gypsum, zinc and borax were also applied at 20-3.7-1.7 kg/ha. Nitrogen was applied in two equal splits, the first along with phosphorus and potash at the time of soil preparation while the remaining half was applied during apparent flowering and umbel formation of crops. The unit plot size was 3m x 1 m. Onion bulbs were planted on 16 October 2011 in 25 cm apart rows maintaining plant to plant distance 20 cm. Bulbs were set upright and at a depth of 2.5 cm at 60 bulbs per plot. Measured amount of water was applied to each plot at several intervals to maintain the soil moisture content in the root zone up to field capacity. The crop was kept weed free by manual hoeing. Ten plants from each plot were selected randomly at harvest for collection of data on growth, yield components and yield. The selected treatments were: T1: Irrigations at vegetative, bolting, scape elongation, flowering, seed formation and pre-mature stages, T2: Irrigations at bolting, scape elongation, flowering, seed formation and pre-mature stages. T3: Irrigations at vegetative, bolting, scape elongation, flowering and seed formation stages, T4: Irrigations at vegetative, bolting, flowering and seed formation stage, T5: Irrigations at vegetative, scape elongation, flowering and seed formation stages, T6: Irrigations at vegetative, bolting, flowering, seed formation and pre-mature stages, T7: Irrigations at vegetative, bolting, and flowering stages, T8: Irrigations at vegetative, bolting, flowering and pre-mature stages, T9: Irrigations at vegetative, bolting, seed formation and pre-mature stages. Estimation of Irrigation water - The irrigation water was applied to bring the soil moisture content at the root zone to field capacity taking into account the effective root zone depth. Soil moisture was determined both by digital moisture meter and by Gravimetric method before every irrigation. Measured amount of water was applied to all treatments. The effective root zone of onion was considered as 30-40 cm depending on the growth stag. Harvesting and seed extraction - In onion seed crop, the timing of harvest is complicated by the asynchronous pattern of seed growth and development within and between umbels. Furthermore, there is a tendency for seeds to shed soon after physiological maturity as a result of capsule busting. Therefore, selection of optimum harvest time must balance the increase in the number of physiologically mature seeds in umbels over time with the decrease in seed number caused by capsule dehiscence. Although all the seed heads did not mature simultaneously, there was only one cutting. Statistical analysis - The recorded data on different parameters were statistically analyzed by using MSTAT software to find out the significance of variation resulting from the experimental treatments. The difference between the treatment means were judged by Duncan’s Multiple Range Test (DMRT).
Eco-friendly Agril. J. 6(02): 34-39, 2013 (February); ISSN 1999-7957
Journal