生姜品种对镉胁迫的生理响应及耐镉性评价

为筛选耐Cd种质资源并研究生姜耐Cd机理,以华东、华中和西南主产区的5个主栽品种凤头姜、贵州小黄姜、罗平小黄姜、竹根姜和山东大姜为试验材料,设置对照(CK)和镉(Cd)处理,两处理的水分处理一致,CK无外源添加Cd。测定生姜生长指标和生理指标,利用主成分分析和隶属函数法对5个品种苗期的耐Cd性进行综合评价。结果表明:Cd处理显著(P<0.05,下同)降低了生姜的株高、茎粗、过氧化氢酶(CAT)活性、光合色素含量及PSⅡ最大光化学效率(F_v/F_m)、光化学猝灭系数(qP);显著升高了叶片中的硫代巴比妥酸反应物(TBARS)含量、超氧化物歧化酶(SOD)活性及非光化学猝灭系数(NPQ);山东大姜的过氧化物酶(POD)活性、游离脯氨酸(Pro)与类胡萝卜素(Car)含量无显著变化。综合评价5个品种生姜的耐Cd性排序为山东大姜>贵州小黄姜>罗平小黄姜>凤头姜>竹根姜。相关性分析结果表明茎粗、Car含量与综合评价值(D值)呈极显著(P<0.01)正相关,叶片TBARS含量、POD活性与D值呈显著负相关(P<0.01)。竹根姜Cd含量是山东大姜的3.57倍,Cd主要富集在根和叶中,山东大姜的Cd主要富集在根中。5个品种中山东大姜耐Cd性最强,竹根姜耐Cd性最差。茎粗、Car含量、叶片TBARS含量和POD活性可以作为生姜耐Cd品种筛选的主要参考指标。

Physiological response and cadmium tolerance evaluation of ginger cultivars to cadmium stress

This study aimed to explore the effects of cadmium (Cd) stress on morphological characteristics and physiological indices of ginger at the seedling stage, screened Cd-tolerant germplasm resources, and established an evaluation system for Cd tolerance of ginger. The findings provide a reference for research on Cd-resistant mechanisms of ginger and breeding of Cd-resistant varieties. Five main cultivars in the main ginger producing areas of East, Central, and Southwest China (fengtoujiang, guizhouxiaojiang, yunnanxiaojiang, zhugenjiang, and shandongdajiang) were the experimental materials. Normal water treatment (control, CK) and Cd water treatment were consistent. CK was not an external addition to Cd treatment. The characteristics of growth and physiological indices, chlorophyll, and chlorophyll fluorescence were determined for CK and Cd treatments. Principal component analysis and membership function approach were used to assess the Cd tolerance of the five cultivars at the seedling stage. Cd treatment significantly decreased plant height, stem diameter, catalase activity, photosynthetic pigment content, F_v/F_m and photochemical quenching coefficient (P<0.05). Thiobarbituric acid reactive substances(TBARS), superoxide dismutase, and non-photochemical quenching coefficient in leaves were significantly increased (P< 0.05). There were no significant changes in peroxidase (POD) activity, and the contents of proline and carotenoid(Car) in shandongdajiang. The comprehensive evaluation results ranked the Cd tolerance of the five ginger varieties as shandongdajiang> guizhouxiaojiang>yunnanxiaojiang>fengtoujiang>zhugenjiang. Stem diameter and Car content were positively correlated with D value (P< 0.01). TBARS content and POD activity in leaves were negatively correlated with D value. The Cd content of zhugenjiang was 3.57 times that of shandongdajiang. Cd was mainly enriched in the roots and leaves of zhugenjiang and in the roots of shandongdajiang. Among the five varieties, shandongdajiang and zhugenjiang had the strongest and poorest Cd tolerance, respectively. Stem diameter, Car and TBARS contents, and POD activity in leaves could be the main reference indices for screening Cd-tolerant varieties of ginger.