Scion Root Affects Flowering, Yield, and Nutrient Status in ‘Shiranuhi' Mandarin Hybrid

Deep plantation caused scion root in 'Shiranuhi' Mandarin. That made problems on flowering, yield, and fruit quality in many farmlands in Korea. Usually, the scion root appears from the joint between rootstock and scion if the rootstock is deeply planted or insufficiently exposed from the soil surface. To know the effect of scion root on the ‘Shiranuhi’ Mandarin, we evaluated the photosynthesis, growth, nutrition of root, flowering, and fruit quality. Flowering and yield of scion rooted tree severely declined. In mature fruits, quality such as size, weight, and soluble solid contents were reduced. Growth of scion rooted tree was vigorous and increased a trunk size. Response of photosynthesis (Aco₂, gs, E, Ci) was increased in the scion rooted tree, but, VpdL was decreased. Nitrogen stock in root was increased, however, carbon stock was lowered in scion rooted tree. Also, accumulation of macronutrients such as P, Ca, and Mg in root was slightly lowered, but K was significantly higher in scion rooted 'Shiranuhi' Mandarin.