Growth and yield of rabi onions as affected by inorganic, integrated and organic nutrient sources in South Bihar

Abstract

During the Rabi seasons of 2016-17 and 2017-18, a field experiment was carried out at Bihar Agricultural University's Nalanda College of Horticulture, Noorsarai, to assess the impact of inorganic, integrated, and organic fertilizers on the growth and yield of rabi onions. The soil of the experimental plot had 262, 14.60 and 142 kg ha-1 of available N, P, and K, a pH of 7.47, an EC of 0.21, and a 0.62 percent organic carbon content. There were seven different inorganic, organic, and integrated sources viz., T1-inorganic fertilizer (IF) 120:60:40; T2-50%NPK through IF+50% N through FYM; T3-50% N through FYM+50% N through VC; T4- 1/3 of N each through FYM + VC + Neemcake; T5-50% N through FYM + PSB + Azotobactor; T6-T3+PSB + Azotobactor and T7-T4+PSB + Azotobactor have been taken for study. The experiment was conducted in randomized block design (RBD) with three replications. Results showed that plant height differed significantly due to different treatments at 30 and 60 days after transplanting (DAT). At both the stages, 100% inorganic fertilizer (T1) recorded highest plant height (25.9 and 38.7 cm) followed by T2 and T6. Although at 90 DAT maximum height was noted in T1, but no significant difference were found in treatments mean. Number of leaves didn’t differ significantly during early stage of crop growth but during later stage (90 DAT) it differed significantly and recorded highest in T1 (5.9) followed by T3, T2, T4 and T6. Equatorial diameter of the bulb differed significantly and found maximum in T1, T2 and T6. Bulb yield differed significantly and found highest in T1 (238.0 q ha-1) which was at par with T2 (222.2 q ha-1) and T6 (195.9 q ha-1). Net return; differed significantly and recorded maximum in T1 (1.47 Lac ha-1) followed by T2 (1.29 Lac ha-1) and T6 (0.97 Lac ha-1). B: C ratio also differed significantly and found highest in T1 (3.36). It may be due to low input cost and high yield. On the basis result obtained T2 as 50%NPK through inorganic fertilizer + 50% N through FYM can be adapted as sustainable crop production being at par with 100% inorganic fertilizer sources.