水氮耦合对旱藕产量、生理特性和土壤理化性状的影响

Effect of water and nitrogen coupling on the yield and physiology characteristics of edible canna and the physical and chemical properties of soil

【目的】探讨水氮耦合对旱藕生长特性及土壤环境的影响,为旱藕的高产高效栽培及其产业的可持续发展提供参考依据。【方法】在遮雨棚内种植旱藕品种桂兴芋3号,设计4个灌水量水平[分别为田间持水量的(20±5)%(W1)、(40±5)%(W2)、(60±5)%(W3)和(80±5)%(W4)]和4个施氮量水平[分别为施纯氮0 kg/hm^(2)(N0)、300 kg/hm^(2)(N1)、600 kg/hm^(2)(N2)和900 kg/hm^(2)(N3)],共16个水氮耦合处理,以W1N0为对照(CK),测定分析各水氮耦合处理旱藕的土壤理化性状、土壤酶活性及旱藕的农艺性状、叶片生理特性和块茎产量。【结果】随着灌水量的增加,种植旱藕土壤的孔隙度、碱解氮含量、脱氢酶活性、蔗糖酶活性及旱藕的茎径、淀粉含量和块茎产量均呈先增加后减少的变化趋势;在缺氮条件下,土壤有效磷含量、速效钾含量、磷酸酶活性及旱藕的分蘖数和株高均随着灌水量的增加逐渐增加。随着施氮量的增加,种植旱藕土壤的孔隙度、蔗糖酶活性及旱藕的株高和茎径均表现先增加后减少的变化趋势;在低水条件下,土壤碱解氮含量、有效磷含量、速效钾含量、脲酶活性及旱藕的分蘖数和块茎产量均随着施氮量的增加逐渐增加。与CK相比,各水氮耦合处理旱藕的块茎产量增加7.78%~70.28%,其中W3N2处理的块茎产量最高。方差分析结果表明,水氮耦合效应对旱藕土壤碱解氮含量、有效磷含量、酶活性及对分蘖、株高和淀粉含量的影响达显著(P<0.05)或极显著(P<0.01)水平,对土壤孔隙度、速效钾含量及茎径、可溶性糖含量、可溶性蛋白含量的影响不显著(P>0.05)。【结论】田间持水量(60±5)%和施氮量600 kg/hm^(2)的水氮耦合模式对改善旱藕土壤环境及促进旱藕生长的综合效果较佳,适宜在旱藕种植区推广应用。

【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)%(W1),(40±5)%(W2),(60±5)%(W3)and(80±5)%(W4)]of field capacity]and four nitrogen application rates[pure nitrogen application of 0 kg/hm^(2)(N0),300 kg/hm^(2)(N1),600 kg/hm^(2)(N2)and 900 kg/hm^(2)(N3)]were designed.A total of 16 water nitrogen coupling treatments were used with W1 N0 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/hm^(2) 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.