Introduction: Mung bean (Vigna radiata L.) is a significant legume with considerable economic and nutritional value in Iran. There has been an increased focus on sustainable agriculture in recent years. One of the sustainable agricultural practices, intercropping mung bean with common millet (Panicum miliaceum L.), increases production, improves product quality, reduces pest and disease damage, and conserves natural resources, among other benefits. The objective of this study was to examine the impact of plant spacing on the yield, yield components, and quantitative properties of mung bean when grown in pure cropping conditions or in combination with common millet.
Materials and methods: The present study was carried out at the research farm affiliated with the Faculty of Agriculture, Zabol University, during the 2013-2014 year. Utilizing a randomized complete block design with three replications, the experiment was conducted. The treatments comprised mixed row cropping of mung bean and common millet with 50 cm row spacing and intra-row spacing of 5 cm between common millet plants and 20, 25, 30 and 35 cm between mung bean plants, and mixed row cropping of mung bean and common millet with 50 cm row spacing and intra-row spacing of 20, 25, 30 and 35 cm between mung bean plants. The parameters examined in mung bean were plant height, branch count, pod count, seed count per pod, and seed yield. For common millet, the parameters assessed were plant height, dry forage yield, and panicle count per plant. Additionally, the land equivalent ratio of various mixtures was assessed.
Results and discussion: The findings indicated that both pure and mixed cropping mung bean yield and yield components were significantly influenced by plant spacing. Pure cropping was conducted with 15 cm plant spacing, which resulted in the highest seed yield, biological yield, number of seeds per plant, and thousand seed weight, in that order. The highest seed yield, biological yield, thousand seed weight, and number of seeds per plant were all observed with a 20 cm plant spacing in mixed cropping. The quantity of plants per unit area exhibited a decline as the plant spacing increased. Nevertheless, with a 15 cm plant spacing, both the quantity of seeds per plant and the weight per thousand seeds increased, leading to a notable boost in seed yield. Mixed cropping resulted in a reduction in competition between mung bean and common millet and an increase in mung bean yield as plant spacing increased. The findings of this study indicated that variations in plant spacing impacted the region's economy, ecology, and society in distinct ways. The ideal distance between mung bean plants in pure cropping was 15 centimeters, while in mixed cropping with common millet, it was 20 centimeters.
The treatment consisting solely of common millet produced 2234.66 kg per hectare of dry forage, while the treatment consisting solely of mung bean produced 323.3 kg per hectare of seeds. The experimental conditions that led to the greatest plant height for common millet (45.9 cm) and mung bean (27.52 cm) were pure common millet cropping and mixed common millet and mung bean cropping with 20 cm intra-row spacing, respectively. In mixed cropping of mung bean and common millet with 25 and 30 cm intra-row spacing, the land equivalent ratio was greater than one, indicating that mixed cropping is more productive than pure cropping. 1.38 was the maximum land equivalent ratio observed in the mixed treatment.
Conclusion: Plant spacing had a significant impact on the yield and yield components of mung bean in both pure and mixed cropping, according to the findings of this study. pure cropping was conducted with 15 cm plant spacing, which resulted in the highest seed yield, biological yield, number of seeds per plant, and thousand seed weight, in that order. The highest seed yield, biological yield, thousand seed weight, and number of seeds per plant were all observed with a 20 cm plant spacing in mixed cropping. Based on the findings of this study, it is advisable to maintain a plant spacing of 15 cm for mung bean in pure cropping and 20 cm for mung bean and common millet mixed cropping.