水氮耦合对旱藕产量、生理特性和土壤理化性状的影响.

[Objective] The present paper aimed to explore the effects of water and nitrogen coupling on the growth characteristics of edible canna and soil environment, so as to provide reference basis for high-yield and high-efficiency cultivation and sustainable development of industry of edible canna. [Method] Edible canna variety Guixingyu 3 was planted in a canopy. Four irrigation water quantities [( 20 ± 5 )% ( Wl), ( 40 ± 5)% ( W2), ( 60 ± 5)% ( W3)and ( 80 ± 5)% ( W4)J of field capacity J and four nitrogen application rates [pure nitrogen application of O kg/hm² (NO),300 kg/hm² (Nl),600 kg/hm² ( N2 )and 900 kg/hm2 (N3)J were designed. A total of 16 water nitrogen coupling treatments were used with Wl NO as control ( CK). The soil enzyme activity, soil physical and chemical properties, agronomic properties, leaf physiological characteristics and tuber yield of edible canna were measured and analyzed. [Result] With the increase of irrigation, soil porosity, alkali hydrolyzable nitrogen content, dehydrogenase activity, sucrase activity, stem diameter, starch content and tuber yield increased first and then decreased. Under the condition of nitrogen deficiency, the content of available phosphorus, available potassium, phosphatase activity, tiller number and plant height of edible canna increased gradually with the increase of irrigation. With the increase of nitrogen application, the soil porosity, sucrase activity, plant height and stem diameter of edible canna increased first and then decreased. Under low water condition, soil alkali hydrolyzable nitrogen content, available phosphorus content, available potassium content, urease activity, tiller number and tuber yield of edible canna increased gradually with the increase of nitrogen application. Compared with CK, the tuber yield of edible canna under each water and nitrogen coupling treatment increased by 7 . 78 % - 70. 28 %, and the yield of W3 N2 was the highest. The results of variance analysis showed that the coupling effect of water and nitrogen had a significant (P < 0. 05)or extremely significant (P < 0. 01) effect on alkali hydrolyzable nitrogen content, available phosphorus content, enzyme activity, tiller number, plant height and starch content, but had no significant effect on soil porosity, available potassium content, stem diameter, soluble sugar content and soluble protein content (P > 0. 05 ). [Conclusion] The water nitrogen coupling model with field water capacity of (60 ± 5 )% and nitrogen application rate of 600 kg!hm2 has a better comprehensive effect on the improvement of soil environment and the growth of edible canna, which is suitable for popularization and application in edible canna planting area. [ABSTRACT FROM AUTHOR]