Growth and yield performance of Vigna radiata (L.) R.Wilczek influenced by altitude, nitrogen dose, planting pattern and time of sowing under sole and intercropping with maize

Abstract

Description of the subject. Mungbean (Vigna radiata [L]. R.Wilczek) is an important summer leguminous crop. It is widely grown in South Asia to fulfill the human nutritious demand of protein, minerals, vitamins and bioactive constituents. It is well suited to be intercropped with cereals in N limited soil to enhance crop productivity through biological nitrogen fixation. Objectives. This paper assesses the impacts of altitude, nitrogen dose, planting pattern and time of sowing on growth and yield parameters of mungbean intercropped with maize in comparison to their sole counterpart. Method. Three-year experiments (2015, 2016 & 2017) were conducted to assess growth and yield performance of mungbean and maize under different environmental conditions and management practices including altitude (1,500; 1,800 and 2,200 m), nitrogen dose (28, 56, 113 kg·ha-1), planting pattern (alternate single row and alternate double row), cropping systems (sole and intercropping), and sowing time of intercropping with maize (simultaneous and staggered). Sole plots of maize and mungbean were also established separately. A Randomized Complete Block Design was used with three replicates. Growth and yield components of mungbean i.e., plant height, leaf area per plant, thousands grain weight, grain yield, biological yield and harvest index were measured. Maize plants were sampled at maturity for computing its grain yield. Results. Orthogonal contrast analysis showed a significant variation in plant height due to year and altitude, leaf area per plant due to intercropping, year and altitude, thousands grain weight due to intercropping, planting pattern and time of intercropping with maize, grain yield due to intercropping, year, altitude and planting pattern, biological yield due to year, altitude and planting pattern, and harvest index due to year and altitude. Moreover, intercropping and management practices influenced maize grain yield. Conclusions. Intercropping reduced the growth and yield performance of mungbean compared to monocropping that is attributed to the competition of resources between two crops. However, this interspecific competition has been mollified at lower altitudes when staggered sowing of mungbean intercropped with maize through alternative double row pattern was done. Consequently, in these conditions mungbean growth and yield was improved.