The occurrence of nutrient-elements toxicity of 'Kyoho' grapevine in water culture, the investigation of nutrient diagnosis standards and the construction of grapevine nutrients diagnosis system

'Kyoho' grapevines, one of the major grape varieties in Japan, were set under deficient conditions of nine essential elements (nitrogen:N, phosphorus:P, potassium:K, calcium:Ca, magnesium:Mg, boron:B, manganese:Mn, zinc:Zn and copper:Cu) and one non-essential element (sodium:Na) in water culture. After each vine was investigated regarding toxicity symptoms, growth, and mineral element content in leaves and grape quality, the diagnosis standards for element toxicities were examined. 1) In boron toxicity, necrosis appeared on the edge of the leaf and leaves turned white yellow in color and dropped just after the shoot started elongating. After June, the leaf shape was round. After August, necrosis appeared on the edge of the leaf and between the leaf veins. The clear symptoms were expressed on leaves and vine growth, grape weight, berry weight and yield decrease. 2) The N, K, Mg, Cu, Mn slightly toxic conditions promoted vine growth and improved yields and grape quality. However, the severely toxic conditions and the Na toxic condition lowered them, and some vines died. Under those toxic conditions, neither clear chlorosis nor necrosis was formed on the leaves. Those toxicities were considered to be a kind of salt damage. 3) The P, Ca, Zn slightly toxic conditions also promoted vine growth and also improved yields and grape qualities. Their severely toxic conditions didn't lower them and brought no effects. The toxic condition of those elements hardly revealed any toxicity within this study. 4) The toxicities of those elements except B effect vine growth and grape quality potentially instead of expressing clear symptoms. Therefore, plant analysis is effective for diagnosing element toxicities. Considering vine growth, grape quality, nutrient interactions and distribution within vines, nutrient diagnosis standards for element toxicities were examined on a maximum leaf concentration for each element : 1.2% (slightly), 2.0% (severely) for K, 2.4% (slightly) for Ca, 0.8% for Mg, 0.8% for Na, 200mg/kg for B, 300mg/kg (root) for Cu, 5000mg/kg (root) for Mn and 70mg/kg for Zn. 5) The authors constructed 'the Grapevine Nutrients Diagnosis System', arranging various data on mineral nutrient deficiency and toxicity.