Effects of Different Crop Intercropping on the Growth, Root System, and Yield of Tiger Nuts

Abstract

Intercropping is a vital cropping system that can create a conducive growth environment for crops and enhance land productivity. Tiger nuts (Cyperus esculentus L.) have high oil content and are adaptable to various soil types, making them a promising new oil crop with significant development potential. This study evaluated the plant height, leaf area, tiller numbers, biomass, land equivalent ratio (LER), and root morphological characteristics of tiger nuts. The agronomic traits and root distribution of tiger nuts and other crops were further investigated to achieve the goal of high yield for tiger nuts. Seven intercropping systems were implemented in the experiment: maize–tiger nut intercropping (MT), soybean–tiger nut intercropping (ST), cotton–tiger nut intercropping (CT), monoculture tiger nut (T), monoculture maize (M), monoculture soybean (S), and monoculture cotton (C). The results indicated that under different planting systems, the agronomic traits of tiger nuts in MT and ST modes were superior, with plant height and tiller numbers increasing by 7.6% to 11.6%. However, the plant height and Soil Plant Analysis Development (SPAD) values in CT mode were slightly lower than in T mode. Additionally, intercropping reduced the leaf area by 6.2% to 37.9%. Root development was more pronounced in intercropping modes, with the ST mode showing the most significant improvement, increasing the 0–20 cm root length density (RLD) by 12.2% to 45.7%. Therefore, each of the three intercropping modes demonstrated distinct advantages. The LER of the intercropping systems ranged from 1.10 to 1.24, enhancing land utilization, with tiger nuts being the dominant species. Compared to monoculture, the ST mode exhibited the best overall effect. Understanding the impact of different planting systems on tiger nuts provides valuable insights for developing tiger nut cultivation in Xinjiang.