Growth, Yield and Quality of Rabi Groundnut (Arachis hypogaea L.) as Influenced by Sources of Calcium and Sulphur under Different Site - Specific Nitrogen Management in Rice-Groundnut Cropping System

The injudicious and imbalanced fertilizer use under the existing farming system necessitates the adoption of amelioration methods and balanced use of nutrients especially nitrogen (N). There is lack of information on effects of various sources of calcium and sulphur in groundnut along with balanced nitrogen management which needs to be addressed. A field experiment was carried out during 2020-21 and 2021-22 at Odisha University of Agriculture and Technology, Bhubaneswar, Odisha, India to study the growth, yield and quality parameters of groundnut as affected by site specific nitrogen management in rice and various sources of calcium and sulphur in groundnut. The experiment was laid out in split plot design with six main plot treatments i.e. Soil test based nitrogen (STBN) (100 kg N/ha), 75% N through STBN + 25% N through farmyard manure (FYM), 75% N through STBN + 25% N through vermicompost, N @ 20kg at basal and at leaf colour chart (LCC) < 3, N @ 20kg at basal and at chlorophyll value determined by soil plant analysis development (SPAD) < 35 and no nitrogen to rice during Kharif and three sub plot treatments i.e. lime @ 0.2 LR, gypsum @ 250 kg/ha and lime @ 0.2 LR + gypsum @ 250 kg/ha to groundnut during Rabi each in three replications. Application of 75% N through STBN + 25% N through vermicompost to preceding rice and lime @ 0.2 LR+ gypsum @ 250 kg/ha to groundnut crop resulted in highest plant height at harvest, number of nodules per plant and dry matter accumulation at harvest. Yield attributing characters like pods/plant, kernel/pod and 100 - pod weight of groundnut were highest due to application of 75% N through STBN + 25% N through vermicompost to preceding rice (17.86, 1.87 and 67.2 g, respectively) followed by 75% N through STBN + 25% N through FYM. Application of lime @ 0.2 LR + gypsum @ 250 kg/ha to groundnut recorded more pods/plant (16.86), kernels/pod (1.78) and 100 - pod weight (66.39 g). The treatment receiving 75% N through STBN + 25 % N through vermicompost in rice and application of lime @ 0.2 LR + gypsum @ 250 kg/ha to groundnut resulted significantly maximum pod yield (2,596 kg/ha and 2,291 kg/ha), haulm yield (4,554 kg/ha and 4,343 kg/ha) and harvest index (36.30% and 34.38%) in groundnut. Oil yield (682.2 kg/ha) in groundnut was recorded highest in the treatment lime @ 0.2 LR + gypsum @ 250 kg/ha followed by only gypsum @ 250 kg/ha application to groundnut. Similarly, application of lime @ 0.2 LR + gypsum @ 250 kg/ha to groundnut recorded highest protein yield (424.6 kg/ha).