Abstract:

The comprehensive effects of K, P, N fertilizer and water on quality and yield of Lettuce was studied by means of quadratic general rotational (1/2 practice) combination design in the greenhouse. The results showed the extremely significant regression relation between water-fertilizer coupling and lettuce quality and yield was observed. The maximum effect of four factors on VC and yield of lettuce was phosphatic fertilizer, then quantity of water; nitrogenous fertilizer; potash fertilizer. The effect order of four factors on soluble sugar of lactuca was phosphatic fertilizer>nitrogenous fertilizer>quantity of water>potash fertilizer. The optimal combination scheme of water-fertilizer coupling was obtained, the rate of nitrogenous fertilizer was from 518.3 to 583.5 kg/hm2, the rate of phosphatic fertilizer was from 536.1 to 626.3 kg/hm2, the rate of potash fertilizer was from 150.0 to 154.5 kg/hm2, and the rate of water quantity was from 537.2 to 545.9 m3/hm2.