Integrating horticultural practices with smallholder resources improves Rosa roxburghii yield and nitrogen use efficiency

Rosa roxburghii Tratt is one of the main cash crops in mountainous areas of Guizhou where production is a large contributor to the income of smallholders. In Guizhou Province, cultivation of R. roxburghii is largely dominated by smallholders employing extensive management practices, which typically results in low yield and economic challenges. Moreover, the effect of integrated and localized horticultural practices and smallholder resource endowment on yield and resource use efficiency is not well understood. In this study, localized technology and nitrogen use efficiency were assessed for 121 smallholders growing R. roxburghii in the main production zone in Guizhou Province. The average yield of R. roxburghii among smallholders was 5.9 t ha^-1. Based on yield and nutrient use efficiency, smallholders were categorized into four groups. The yield of the high-yielding and high-efficiency (HH) group was 8.4%, 99.1%, and 97.8% higher than that of the high-yielding and low-efficiency (HL), low-yielding and high-efficiency (LH), and low-yielding and low-efficiency (LL) groups, respectively. The partial factor productivity of the HH group's Nitrogen fertilizer (PFP-N) was 501.6%, 31.7%, and 589.0% higher than that of the HL, LH, and LL groups, respectively. Educated smallholders in the HH group employed optimized horticultural practices, including chemical fertilizer, pruning, pest control, planting density, and weed control. Thus, smallholder farm-led R. roxburghii crop production demonstrates great potential for high yield and efficient nitrogen use through the coupling of localized technology and the resource endowment of smallholders.