氮硫互作对大蒜幼苗生长与抗氧化酶活性的影响

Influence of Nitrogen and Sulfur Interaction on Growth and Antioxidant Enzymes Activities of Garlic Seedlings

采用蛭石盆栽方式,研究不同浓度氮(5、10、20、40mmol·L-1,记作N1、N2、N3、N4)、硫(1、2、4、8mmol·L-1,记作S1、S2、S3、S4)配施条件对大蒜幼苗生长与抗氧化酶活性的影响。结果表明,随氮硫互作浓度的升高,大蒜幼苗的株高、茎粗、生物量及分配、根系活力以及叶片与根系中过氧化物酶(POD)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)活性整体均呈先上升后下降的趋势。大蒜幼苗期对氮素的需求量较低,N1表现最好;而对硫素有一定的需要,S2表现最佳。氮素含量超过N3或硫素含量超过S3,对大蒜幼苗生长有明显的抑制作用。氮、硫2种元素对幼苗期大蒜的生物量分配与叶片中抗氧化酶活性无显著影响,而氮硫交互作用对幼苗根系以及叶片中抗氧化酶活性影响均达到显著或极显著水平。综合考量,氮素含量在5 mmol·L-1、硫素含量在2 mmol·L-1时最适于大蒜幼苗生长,且2种元素配施存在明显的互作效应。本研究为大蒜幼苗期施肥以及"植物工厂"生产模式提供了理论指导。

A pot experiment was conducted by using four levels of N and S applied in factorial combinations of 5,10,20,and 40mmol·L^-1and 1,2,4,and 8mmol·L^-1in vermiculite culture to investigate the effects of nitrogen and sulfur interaction on garlic seedlings growth and antioxidant enzymes activities. The results indicated that plant height,stem diameter,root activity,biomass and distribution,antioxidant enzymes（ POD,CAT,SOD） activities in leaf and root increased firstly and then decreased,with the increasing concentration of nitrogen and sulfur interaction. The demand for nitrogen,N1 level was optimal; for sulfur,S2 was the most suitable at garlic seedling stage. When the nitrogen content in more than 20mmol·L^-1or sulfur concentration more than 4 mmol·L^-1,plant growth was retarded.Nitrogen and sulfur had no significant effect on distribution of biomass and antioxidant enzymes activities of garlic seedling leaf. However,the influence of nitrogen and sulfur interaction on roots and antioxidant activities in leaves of garlic seedlings reached significant or extremely significant level. The results showed that the nutrient solution containing5mmol·L^-1N and 2mmol·L^-1S was optimal for garlic seedlings,and two elements with obvious interaction effect.The study provides practical theory basis for fertilization on the garlic seedling stage and ＇plant factory＇ pattern.