Effects Of Potassium In Nutrient Solution On Physiological And Biochemical Characteristics And Quality Of Garlic

Effects of different potassium concentration on physiological and biochemical charactristics, fresh weight and qualities of garlic were studied by nutrient solution, so as to a reasonable potassium fertilizer application on garlic as a reference was provided. Jinxiang White Garlic were tested in this research by means of nutrient solution (DFT) experiments, with Hoagland nutrient solution based, five potassium applications levels of 0 mmol·L^-1,3.0 mmol·L^-1,6.0 mmol·L^-1,9.0 mmol·L^-1and 12.0 mmol·L^-1 were designed to investigate the effects of potassium on biology characteristic, photosynthesis, fresh weight and quality, accumulation of N,P,K of garlic.The main results were as following:1. Appropriate concentration of K⁺ in nutrient solution can significantly promote the height, pseudostem diameter, leaf length and leaf width and root length and leaf number of Jinxiang White Garlic at seedling, and with 6.0 mmol·L^-1 for the best, which laid a foundation for manufacturing and storing more photosynthate for the late bolt elongation and bulb division, expansion. Meanwhile, root activity was higher in the concentration. When the concentration of K⁺ was more than 6.0 mmol·L^-1, it was unfavorable to improve the above index.2. In the range of 0⁶.0 mmol·L^-1 , that garlic functional seedling leaf total chorophyll, carotenoid content and net photosynthetic rate increased with increasing concentration of K⁺, and then decreased with increasing concentration of K⁺ between 6.0¹2.0 mmol·L^-1. And it was best when the concentration of K⁺ was 9.0 mmol·L^-1 at the stage of bolt elongation and bulb division, expansion.3.With concentration of K⁺ 6.0 mmol·L^-1, the SOD and CAT acativity were heighest, while POD and APX acativity were lowest at seedling of garlic. And the above indicators were best when K⁺ concentration was 9.0 mmol·L^-1at actively growth period of garlic. MDA content were heighest at both seedling and actively growth period of garlic.4. Potassium promoted garlic fresh weight. For one thing, potassium increased the number and aliber of garlic, and reduced the rate of secondary growth; For another, it promoted the fresh and dry weight of bolt and bulb. compared with the treatment of 0 mmol·L^-1 K⁺ concentration, the fresh and dry weight increased by 195%³53.75% and 201.69%³21.99% ,respectively, in bolt, while these indexes increased by 180.90%²58.85% and 180.80²58.70%, respectively, in bulb. And the K⁺ concentration with the best effect was 9.0 mmol·L^-1. 5. Potassium had an obviously effect on nutrient quality of garlic. The contents of soluble sugars, vitamin C, soluble proteins and allicin of garlic leaf and pseudostem increased with K⁺ concentration ranging from 0⁶.0 mmol·L^-1, and then decreased. Compared with 0 mmol·L^-1 K⁺, the treatment of 9.0 mmol·L^-1 K⁺ enhanced the contents of soluble sugars, vitamin C, soluble proteins and allicin by 67.0%,31.22%,79.38% and 76.38%, respectively, in garlic sprout, while these indexes increased by 91.51%,45.61%,91.47% and 99.26%, respectively, in bulb.6. The proper concentration of potassium in nutrient solution caould promote the absorption and accumulation of N, P, K in bolt and bulb,and the total nitrogen c and total phosphorus content and total potassium content of bolt and bulb were the heighest with the K⁺ content was 9.0 mmol·L^-1.