Effects of Camellia oleifera clone selection on soil nutrient and microbial community structure

Camellia oleifera Abel. is an important woody oil plant that could solve the disparity between the supply and demand of edible oil in China. Although numerous excellent clones have been developed and introduced to enhance production, the interactions between high yield clones and soil ecosystem sustainability remains poorly understood. The high-yielding period of a C. oleifera plant is approximately 100 yr; therefore, appropriate clone selection is crucial. We evaluated the differences between four major clones based on soil nutrient and microbial community structure, following cultivation for 10 yr to infer the influence of clone selection on soil sustainable utilization. The results showed significant differences in soil nutrient status and rhizosphere microorganism populations among clones. The bacterial communities in the XL1 plots had the highest species richness. According to the results, clone XL1 was found to be suitable for sustainable cultivation considering the high organic matter concentration and microbial diversity in the soil where it was cultivated. Although clone XL210 exhibited high yields and good economic benefits, it had a risk of inadequate production capacity in later periods, meaning that fertilization rates would have to be increased, and some annual plants with rich rhizosphere flora would need to be integrated in the farms to enhance microbial diversity in the soil to decelerate soil fertility decline.