Effects of potassium fertilization on fodder yield and root system of Avena sativa cv. Qingyin No.1

Effects of potassium fertilization on dry matter yield and root system of Avena sativa cv. Qingyin No.1 were studied to optimize the potassium application for oats production in a potassium deficient area. The results show that the optimum fodder and protein yields of the cultivar are 29575.0 kg/ha and 2099.8 kg/ha respectively at the blossom stage under the N 54.75 kg/ha, P2O5 51.75 kg/ha and K2O 40 kg/ha fertilization. Relation between dry matter, protein yield and K application can be described as Y=a+bK+cK2. Under the K2O 40 kg/ha treatment, the plant height, tiller, root length and root number of the cultivar are the highest, are about 184.5 cm, 3.22 till/plant, 15.90 cm and 26.17 roots/plant, respectively. Under the 20 kg/ha K2O fertilization, diameter of stem and root weight are the highest, 0.585 cm and 0.540 g/plant, respectively. There are significant correlations between above-ground, under-ground yields and fodder, protein yields.