STUDY ON EFFECTS OF POTASSIUM DOSES ON YIELD AND QUALITY OF SWEET POTATO VARIETY HNV1 IN WINTERSPRING SEASON IN HOANG HOA DISTRICT, THANH HOA PROVINCE

Abstract

The study was carried out to clarify the effects of Potassium doses on the growth, yield and quality of sweet potato variety HVN1 in 2020 - 2021 in Hoang Hoa district, Thanh Hoa province. Four treatments with different doses of K2O (80, 100, 120, 140 kg/ha), were experimented of which the treatment with 100 kg K2O was the control. The results showed that applying K2O had a possitive effect on the growth, yield and quality of the sweeet potato variety. The treatment of 120kg/ha K2O gave the longest stem (156,9 cm), highest number of tubers/plant (3.18 tubers/plant) and biggest tuber weight (466,6g/tuber). It also provided the highest yield, dry matter content and starch content (48,42 tons/ha, 30,6% and 23,3%, respectively), and the highest value cost ratio (VCR) of 21,24. Economic optimum dose of K2O was indentified as 121 kg/ha and technical optimum dose of 119 kg/ha.