ABSTRACT

High bicarbonate concentration in alkaline and calcareous soils is an important inducing factor of iron (Fe) chlorosis in plants. The purpose of this study was to investigate the effects of bicarbonate (15 and 30 mM) and Fe sources (FeEDTA and FeSO₄.7 H₂O) on vegetative growth and physiological traits of four grapevine cultivars in hydroponic systems. In this study a factorial experiment was conducted based on a completely randomized design with four replications. Results showed that bicarbonate and Fe-deficient (FD) treatments decreased total fresh and dry weights in all cultivars. Results also indicated that absolute growth rate significantly decreased under high bicarbonate (HB) concentration in all cultivars. The concentration of total Fe in shoot decreased under HB in Yaghouti, Flame Seedless and Rotabi cultivars (26%, 25%, 23% compared to their control plant respectively) however, the existence of bicarbonate had little effect on shoot Fe concentration of Thompson Seedless cultivar in both Fe sources (FeEDTA and FeSO₄.7 H₂O). Results indicated that leaf malondialdehyde (MDA) contents increased under HB in all cultivars and both Fe sources whereas MDA was increased in Thompson Seedless and Flame Seedless as well as Rotabi cultivars under FD treatment. Generally according to our results, cultivars showed different responses to bicarbonate and Fe deficiency, Thompson Seedless cultivar showed higher tolerance to bicarbonate application and Yaghouti and Flame Seedless cultivars had more tolerance under Fe-deficient conditions.

摘要

碱性和钙质土壤中的高碳酸氢盐浓度是植物铁 (Fe) 萎黄病的重要诱导因素。本研究的目的是研究碳酸氢盐（15 和 30 mM）和 Fe 源（FeEDTA 和 FeSO ₄ .7 H ₂O) 对四种葡萄栽培品种在水培系统中的营养生长和生理性状的影响。在这项研究中，基于完全随机设计的因子实验进行了四次重复。结果表明，碳酸氢盐和缺铁 (FD) 处理降低了所有品种的总鲜重和干重。结果还表明，所有品种在高碳酸氢盐 (HB) 浓度下绝对增长率显着降低。Yaghouti、Flame Seedless 和 Rotabi 品种在 HB 下地上部总 Fe 浓度降低（分别比对照植物降低 26%、25%、23%），但碳酸氢盐的存在对 Thompson Seedless 地上部 Fe 浓度影响不大两种铁源（FeEDTA 和 FeSO ₄ .7 H ₂哦）。结果表明，HB 处理下所有品种和两种铁源的叶丙二醛 (MDA) 含量均增加，而 Thompson Seedless 和 Flame Seedless 以及 Rotabi 品种在 FD 处理下的 MDA 含量增加。总的来说，根据我们的结果，品种对碳酸氢盐和铁缺乏表现出不同的反应，汤普森无核品种对碳酸氢盐的应用表现出更高的耐受性，而 Yaghouti 和火焰无核品种在缺铁条件下表现出更高的耐受性。