Effect of Al in Soil on Photosynthesis and Related Morphological and Physiological Characteristics of Two Soybean Genotypes

土壤中鋁污染對兩種大豆品種光合特性及相關形態和生理特性的影響

張曉斌(Xiao-Bin Zhang) ； 劉鵬(Peng Liu) ； Y. S. Yang ； 徐根娣(Gen-Di Xu)

《Botanical Studies》 48卷4期 (2007/10) Pp. 435-444

摘要

從光合特性及其相關的形態和生理特性方面研究了土壤中鋁對兩種大豆品種的影響。我們以2個大豆(Glycine max Merrill.)品種華春18、浙春3號為材料，設置不同的鋁濃度進行盆栽土培，在五葉期取樣測定各項指標。結果表明：微量鋁對大豆的生長具有一定的促進作用，鋁僅在超出一定值時才對植物產生毒害。200 mg/kg Al(subscript 3+)處理下，葉面積和比葉重較對照有所增加，丙二醛含量有所降低。高濃度的鋁對大豆產生了不利影響。鋁濃度大於 800mg/kg情況下，葉綠素含量下降，光合速率降低，蒸騰速率增高，光利用率和水分利用率下降，而對氣孔導度和葉水勢沒有顯著影響。並且，高濃度的鋁顯著提高了膜脂過氧化程度，降低了細胞膜穩定性，改變了大豆葉 SOD 活性。植物通過保持 SLW、P(subscript N)、PUE、WUE和SOD活性來適應高鋁脅迫。本研究結果為日後進行耐鋁型大豆的選育工作提高了基礎。

關鍵字

大豆 ； 鋁 ； 光合特性

並列摘要

Ecological impact assessments of contaminated soil on plants has been an interesting area in the last few years as restoration of contaminated environments for better ecological health is addressed. In this study, the photosynthetic and related morphological and physiological characteristics of two soybean (Glycine max Merrill.) varieties were evaluated in response to aluminum (Al) stress in soil. The pot-grown soybean plants were cultured with different supplemental aluminum, and measurements was conducted during the 5-foliate period. Results indicate that Al at low concentrations in the soil is helpful to growth, and Al is toxic to plants only when the concentration exceeds a certain threshold. Increased leaf area, root surface area, specific leaf weight (SLW), and lower malondialdehyde levels were found in soybean plants under a 200mg/kg Al(superscript 3+)treatment. However, higher aluminum concentrations (800 mg/kg) caused declining chlorophyll contents, depressed photosynthesis rates (PN), enhanced transpiration rates, and decreased PAR utilization efficiency (PUE) and water utilization efficiency. No significant difference in stomatal conductance or leaf water potential was observed among soybean plants under the various aluminum treatments. Moreover, higher aluminum concentration significantly increased lipid peroxidation, decreased cell membrane stability, and changed the activities of superoxide dismutase (SOD) in the leaves of both plants. It is concluded that soybean plants maintain relatively higher SLW, PN, PUE, WUE, SOD activity to cope with high aluminum stress. Ourstudy produces insights into plant behavior under contamination stress, which may be useful in the selection and breeding of aluminum-tolerant soybean cultivars for the sustainable development of agriculture and ecology.

並列關鍵字

Aluminium ； Photosynthetic characteristics ； Physiological characteristics ； Soybean