Bulb yield, pre-mature sprouting and nitrogen use efficiency of garlic varieties as influenced by nitrogen

Abstract

The field experiment was carried out at the research farm of Regional Spices Research Centre, Bangladesh Agricultural Research Institute (BARI), Gazipur (23⁰59^/North Latitude and 90⁰24^/East Longitude) during two successive winter seasons of 2020-21 and 2021-22, to find out the optimum dose of nitrogen and suitable garlic variety for up scaling bulb production. The experiment was laid out in a two-factor randomized complete block design with three replications having four garlic varieties (BARI Rashun-1, BARI Rashun-2, BARI Rashun-3 and BARI Rashun-4) with four different levels of nitrogen (0, 50, 100 and 150 kg ha^-1). A blanket dose of 60-160-20-2-1 kg ha^-1 of P-K-S-Zn-B along with cowdung @ 5 t ha^-1 was applied in each experimental plot. Both factors such as garlic variety and nitrogen level showed significant effects on the yield, yield components, pre-mature sprouting and nitrogen use efficiency of garlic. The highest bulb yield of (8.58 and 8.91 t ha^-1 in 2020-21 and 2021-22, respectively) was obtained from BARI Rashun-3 regardless of N dose. On the other hand, application of 100 kg N ha^-1 produced the highest bulb yield (8.1 and 9.55 t ha^-1 in 2020-21 and 2021-22, respectively). The response of garlic varieties to N was appeared to be quadratic in nature (R² = 0.9914). From the quadratic response function, the optimum dose was estimated to be 92.75 kg ha^-1. The minimum number of pre-mature sprouted bulb (2.5%) was noted in BARI Rashun-4 when N was not applied. The maximum nitrogen use efficiency (138.44 and 144.72% in 2020-21 and 2021-22, respectively) was recorded from BARI Rashun-4 with 50 kg N ha^-1. Among the BARI released garlic varieties, BARI Rashun-3 performed better in this region. Thus, it may be concluded that BAR Rashun-3 could be cultivated by applying 92.75 kg N ha^-1 along with blanket dose of 60-160-20-2-1 kg ha^-1 of P-K-S-Zn-B and cowdung @5 t ha^-1 in the Grey Terrace Soil of Madhupur Tract (AEZ-28).

Bangladesh J. Agril. Res. 49(3): 279-291, September 2024