S. K. Biswas
Senior Scientific Officer
IWM Division, BARI, Gazipur-1701
D. K. Roy
Scientific Officer
IWM Division, BARI, Gazipur-1701
P. K. Sarkar
Principal Scientific Officer
IWM Division, BARI, Gazipur-1701
A. Khatun
Principal Scientific Officer
IWM Division, BARI, Gazipur-1701
A. R. Akanda
Principal Scientific Officer
IWM Division, BARI, Gazipur-1701
This study was executed at the experimental field of IWM Division, BARI, Gazipur to investigate the effect of irrigation on onion seed yield. The results showed that most of the growth and yield contributing parameters like umbel diameter, effective floret per umbel, seed yield per plant and 1000- seed weights were significantly influenced by different irrigation treatments. Other growth parameters such as, plant height, number of flower stalk per plant, length of scape and diameter of scape varied with the irrigation but the variations were not statistically significant. The highest yield (1110.89 and 1067.58 kg/ha in the first and second year, respectively) was observed from the treatment receiving irrigations at four different growth stages while the treatment in which stress was imposed at flowering stage produced the lowest seed yield (897.70 and 846.55 kg/ha in the first and second year, respectively). Water productivity was observed the highest (0.45 kg/m3) in treatment T5 while the lowest (0.38 kg/m3) was observed in treatment T4. The highest benefit-cost ratio (3.69) was obtained from treatment T1 while the lowest (2.93) was obtained from treatment T6.The results suggest that irrigation at the flowering stage may be considered critical for onion seed production.
Irrigation, onion seed yield, benefit-cost ratio
Central farm, IWM Division, BARI, Joydebpur, Gazipur
Crop-Soil-Water Management
The objective of the study was to evaluate the effects of irrigation regimes on onion seed yield and determine the critical growth stage(s) of onion for seed production in response to irrigation.
Field experiment was conducted at the experimental field of Irrigation and Water Management Division of Bangladesh Agricultural Research Institute, Gazipur during the rabi season of 2010 - 2011 and 2011 - 2012. The soil was silty clay loam with field capacity and bulk density, 29% and 1.44 gm/cc, respectively. Onion variety “BARI piaz-1” was used to study the effect of irrigation levels on onion seed production. Bulb to seed method was used for this experiment.
The irrigation treatments were:
T1: Irrigations at vegetative, bolting, flowering and seed formation stages.
T2: Irrigations at bolting, flowering and seed formation stages.
T3: Irrigations at vegetative, flowering and seed formation stages.
T4: Irrigations at vegetative, bolting and seed formation stages.
T5: Irrigations at vegetative, bolting and flowering stages.
T6: Irrigations at vegetative and flowering stages (Farmers practice).
The experiment was laid out in a randomized complete block design with three replications. Recommended doses of fertilizer (150-100-180 kg/ha N-P-K) in the form of urea, triple super phosphate and muriate 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.
The unit plot size was 3 m x 1.2 m. Onion bulbs were planted on 06 December, 2010 and 05 November, 2011 in 30 cm apart rows maintaining plant to plant distance of 20 cm. 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. The crop was harvested on 11 April, 2011 and 14 March, 2012 in the first and second year, respectively. Data were analyzed statistically following MSTAT-C package program and the mean differences were evaluated by Least Significant Difference (LSD).
BARI Annual Report 2011-2012
The yield of onion seed was reasonably affected by the irrigation regimes. Four irrigations and amounting 280 mm of water contributed increasing the seed yield of onion due to the availability of adequate moisture in the root zone during the critical growth stages. Depending on the quantity and timing of irrigation, the applied irrigation imparted different degrees of influence on the various components of growth and yield parameters. The yield was the lowest when stress was imposed on the flowering stage, irrespective of the amount of water applied. So, it can be concluded that flowering stage is the critical stage for onion seed production. Three irrigations including one at flowering stage can be used without any significant yield loss for onion seed production. So, three irrigations each at vegetative, flowering and seed formation stage may be the optimum and feasible irrigation scheduling for onion seed production under irrigation water shortage situation.
Report/Proceedings