紫花風鈴木對干旱脅迫的生理響應

摘要 為評估紫花風鈴木的抗旱能力，本研究以其為材料進行控水試驗，試驗開始后每隔3 d測定栽培基質相對含水量，葉綠素相對含量（SPAD值），丙二醛（MDA）含量，可溶性糖和脯氨酸（Pro）含量以及超氧化物歧化酶（SOD）和過氧化氫酶（CAT）活性，探究其對干旱脅迫的生理響應。結果表明，在干旱初期，MDA含量上升，植物細胞膜受到一定程度的損傷，可溶性糖和Pro等滲透調節物質含量增加，SOD和CAT活性增加，表現出一定的抗旱耐受性；在栽培基質相對含水量低于33.71%后，可溶性糖和Pro含量繼續增加，但SOD和CAT活性逐漸下降，MDA維持在較高水平，表明紫花風鈴木干旱耐受達到極限。綜合以上結果表明，干旱脅迫初期，紫花風鈴木可以通過滲透調節和激活抗氧化酶活性的方式，對干旱脅迫表現出一定耐受性；隨著脅迫程度的增加，其干旱耐受達到極限，SOD和CAT活性下降，其生長受到抑制。

關鍵詞 紫花風鈴木；干旱脅迫；滲透調節；抗氧化酶

中圖分類號 S685.99 文獻標識碼 A 文章編號 1007-7731（2024）19-0057-04

DOI號 10.16377/j.cnki.issn1007-7731.2024.19.012

Physiological response of Handroanthus impetiginosus to drought stress

DOU Suozhu1 YU Xingsheng2

（1Shenzhen Guoyi Park Construction Co.， Ltd.， Shenzhen 518040， China;

2Shenzhen Municipal Group Co.， Ltd.， Shenzhen 518000， China）

Abstract To evaluate the drought resistance of Handroanthus impetiginosus. The water control test was carried out with Handroanthus impetiginosus as the material. After the test， the relative water content， relative chlorophyll content （SPAD）， malondialdehyde （MDA） content， soluble sugar and proline （Pro） content and the activities of superoxide dismutase （SOD） and catalase （CAT） of the cultivated substrate were measured every 3 days to explore the physiological response of Handroanthus impetiginosus to drought stress.The results showed that， in the early stages of drought， the content of MDA increased， plant cell membranes were damaged， soluble sugars and Pro and other osmotic regulatory substances increased， and the activities of SOD and CAT increased， demonstrating a certain degree of drought resistance. After the relative moisture content of the cultivation substrate was below 33.71%， soluble sugars and Pro increased， but the activities of SOD and CAT gradually decreased from their peak， and MDA remained at a high level， indicating that Handroanthus impetiginosus may have reached its drought tolerance limit. These results indicated that Handroanthus impetiginosus could be tolerant to drought stress by osmotic regulation and activation of antioxidant enzyme activity at the early stage of drought stress. With the increase of stress degree， the drought tolerance reached the limit， and the activities of antioxidant enzymes SOD and CAT decreased， which inhibited the growth of Handroanthus impetiginosus.

Keywords Handroanthus impetiginosus; drought stress; osmotic regulation; antioxidant enzymes

“適地適樹”是園林建設的基本原則，體現的是尊重自然，順應自然和保護自然的智慧和基本理念。在城市園林進行植物配置時，應充分考慮當地的自然條件和土壤特性，選擇適應性強、生長穩定且抗逆性好的植物[1-2]。干旱是影響植物正常生長的原因之一[3]。賈益興等[4]通過評估路行道樹樹木安全風險，發現城市環境、自然災害、施工技術以及自身生長特性等因素可能導致樹體傾斜、樹冠偏斜和樹體損傷。因此，對于準備應用于城市園林的樹種，提前進行適應性試驗，以免因存活率不高導致后期維護成本過高等[5]?！?br>