高寒区氮添加和间作种植互作对燕麦和豌豆根系构型影响的研究OA北大核心CSTPCD

Interspecific interactions among plant roots are a crucial pathway to improve the productivity of intercropping systems,and the addition of exogenous nitrogen also plays an important role in altering the architectural characteristics of plant roots.However,few studies have explored the interactive effects of intercropping patterns and nitrogen addition on the architectural characteristics of roots in intercropping systems.We conducted a field experiment to examine the effect of intercropping patterns and nitrogen addition on plant biomass and on the morphological and architectural characteristics of roots in oat-pea intercropping systems.We found that the highest values of above-and belowground biomass for oat were in the alternate-row intercropping system with high nitrogen addition,whereas the maximum biomass of pea was in a monoculture with no nitrogen addition.The root morphological traits of oat in the alternate-row intercropping system with high nitrogen addition were superior to those of monocultured oat.In contrast,in pea,the maximum root area,root volume,and number of root tips were in a monoculture with high nitrogen addition,while the highest number of root forks and maximum altitude and magnitude of roots was in a monoculture with no added nitrogen.The maximum values for the altitude and magnitude of oat roots were in an alternate-row intercropping system,while the maximum value for the altitude of pea roots was in a monoculture with no nitrogen addition.Furthermore,nitrogen addition and intercropping simultaneously had positive effects on oat roots through increasing the root area,volume,and magnitude,and promoting lateral root growth,but had negative effects on pea roots by decreasing the number of connections and tips,reducing the root altitude,and suppressing the growth of lateral root growth.Our findings suggest that both nitrogen addition and intercropping can strengthen the nutrient absorption capacity of roots by increasing the contact area between roots and soil,leading to greater accumulation of biomass.These findings support the hypothesis that oat shows stronger competitiveness and higher productivity than pea when grown in oat-pea intercropping systems.