水杨酸对不同灌水下限青花菜生理特性及产量品质的影响

以青花菜为试材,采用大田试验研究了0.15mmol/L水杨酸(SA)对不同灌水下限(75%、60%和45%土壤相对含水量)青花菜生理特性及产量品质的影响。结果显示:(1)随灌水下限的降低,青花菜叶片相对含水量、水势及叶绿素含量均呈下降趋势,而其叶片电解质渗透率以及游离脯氨酸(Pro)、丙二醛(MDA)、可溶性蛋白(Pr)含量逐渐升高;青花菜的花球重及维生素C含量(Vc)随灌水下限的降低而降低,相反硝酸盐含量及可溶性固形物含量随之升高。(2)叶面喷施0.15mmol/L SA显著提高了青花菜叶片相对含水量、水势、渗透调节物质含量、产量及品质,且降低了膜脂过氧化产物MDA含量,其中以45%灌水下限处理效果最为显著,60%灌水下限处理次之,75%灌水下限处理最小。研究认为,适宜浓度外源SA通过改善青花菜叶片水分生理状况,提高叶片渗透调节物质含量,降低质膜透性来增强其对干旱胁迫的抗性,且以60%灌水下限配合叶面喷施0.15mmol/L SA处理较佳。

Effects of Salicylic Acid on Physiological Characteristics and Yield,Quality of Broccoli under Different Lower Limits of Flood Irrigation

With broccoli as test material,a field experiment was carried out to investigate the effects of 0.15 mmol/L salicylic acid(SA) on physiological characteristics,yield and quality of broccoli under different lower limits of flood irrigation.The results showed that:(1)The leaf relative water content and water potential and chlorophyll content decreased,while the blade penetration proline(Pro) and malondialdehyde(MDA) and soluble protein(Pr) content were gradually increased with the lower of irrigation limit;the flower ball weight and vitamin C content(Vc) decreased with the lower of irrigation limit;on the contrary,the nitrate and soluble solids contents were increased.(2)When spraying 0.15 mmol/L SA significantly increased the leaf relative water content and water potential,osmotic adjustment substance content,yield and quality,while reduce the membrane lipid peroxidation product and MDA content,of which 45% irrigation limit is the most obvious,60% followed,75% minimum.Thus,the suitable concentration of exogenous SA enhance its resistance to drought stress by improving water in broccoli leaves and leaf osmotic adjustment content and reducing membrane permeability,and the lower limit of 60% with spraying 0.15 mmol/L SA handled better.