Effects of Row Spacing on Tiger Nut (Cyperus esculentus L.) Growth Performance and Soil Nutrient Spatial Distribution

Tiger nut (Cyperus esculentus L.) is an oil crop with high potential value. This crop has been popularized in the western region of Inner Mongolia, China, in recent years. Currently, tiger nut is planted and managed in the same manner as local traditional crops. Identifying whether traditional crop management is suitable for tiger nut growth and tuber production in arid areas is critical. The spatial relationship between tiger nuts and soil nutrients in the stolon tillering period and the period before tuber maturation was studied based on the integration of geostatistics, point pattern analysis, and spatial comparison (IGPS) method at three different plant row spacings (30 cm, 40 cm, and 50 cm). High organic matter content aggregation occurred in nontypical patches at 30 cm row spacings after tuber expansion. High total nitrogen content significantly aggregated around tiger nuts in nontypical patches. Some row spacings did not exhibit a spatial correlation between tiger nuts and high total phosphorus content. Among the three row spacings, the 30 cm row spacing produced the most biomass, but there was no significant difference in biomass between 40 and 50 cm. A 30 cm row spacing tends to have production effects; a 50 cm row spacing has weak soil nutrient heterogeneity; and a 40 cm row spacing has no obvious advantages. Tiger nut has a significant response to high nitrogen content. Precise management can be adopted based on this response to produce tubers or pastures.