| 摘要: |
| 为探索一套适合黄土高原地区果园的高效保水模式，提高果树水分利用效率，本研究在盆栽条件下分别以‘楸子’和‘M26’这2种砧木作为试验材料，设置对照(CK)、保水剂处理(A)、埋砖处理(B)和埋砖+保水剂处理(AB)4种处理，探究2种苹果砧木对不同保水处理的生理响应。结果表明:1)埋砖和保水剂均缓解了土壤含水量下降的趋势；从控水的第21天开始，各处理的植株因受到干旱胁迫净光合速率和相对叶绿素含量均开始下降，但3种保水处理较对照均能减缓干旱胁迫对植株生长的影响，维持植株光合速率，稳定叶片相对叶绿素含量。2)埋砖叠加保水剂处理明显缓解了缺水对植株根系长度、根系表面积和根系生长的影响，增大了根冠比，且较好地维持了叶片气孔的数量。3)抗逆性较弱的‘M26’对不同保水措施下的生理响应更敏感，各处理对‘M26’的生长促进效果依次为AB>B>A；对于抗逆性更强的‘楸子’，任何一种保水措施均可减轻缺水对植株根系形态和光合作用的影响。综上，3种不同保水处理均降低了缺水对苗木生长发育的影响，通过保持气孔开放来维持植株正常的光合作用，同时促进根系发育并增加根系吸水面积来缓解干旱胁迫。对于乔化砧木，建议生产中可选择上述处理中单一保水措施或叠加处理保水措施；对于矮化砧木，则应选择叠加处理的保水措施。 |
| 关键词: 干旱胁迫 保水剂 埋砖 苹果砧木 光合作用 根系 |
| DOI：10.11841/j.issn.1007-4333.2023.03.05 |
| 投稿时间：2022-09-15 |
| 基金项目:陕西省重大专项课题(2020zdzx03-01-01)；国家苹果产业技术体系(CARS-27) |
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| Physiological responses of two apple rootstocks to drought stress under different water retention treatments |
|
HU Huatao,FEI Libin,LI Zhaowei,LIU Xiaosheng,XU Xuefeng,WANG Yi,HAN Zhenhai*
|
| (College of Horticulture, China Agricultural University, Beijing 100193, China) |
| Abstract: |
| In order to find out a set of efficient water conservation measures suitable for orchards in the Loess Plateau, and to improve the water use efficiency of fruit trees, ‘Malus prunifolia (Willd. )Borkh. 'and ‘M26' rootstocks were used as experimental materials under pot conditions. The physiological responses of two kinds of apple rootstocks to different water retention treatments were studied by setting four treatments: control(CK), water retaining agent treatment(A), buried brick treatment(B)and buried brick+water retaining agent treatment(AB). The results showed that: 1)Both burying bricks and water-retaining agent alleviated the decreasing trend of soil water content; from the 21 st day of water control, the net photosynthetic rate and SPAD value of all treatments began to decrease due to drought stress. However, compared with the control, the three water conservation treatments could slow down the effect of drought stress on plant growth, maintain plant photosynthetic rate and stabilize leaf SPAD value. 2)The treatment of buried brick superimposed water-retaining agent significantly alleviated the effects of water shortage on plant root length, root surface area and root growth. Water retention treatment increased the root-shoot ratio and maintained the number of stomata in leaves. 3)The physiological response of ‘M26' with weak stress resistance was more sensitive under different water retention treatments, and the growth promoting effect of each treatment on ‘M26' was AB>B>A, while for ‘Malus prunifolia (Willd. )Borkh. ' with stronger stress resistance, any kind of water conservation measures could reduce the effect of water shortage on plants. In summary, three different water conservation treatments reduced the effect of water shortage on plant root morphology and photosynthesis. Water retention treatment alleviates drought stress by keeping stomata open, maintaining normal photosynthesis, promoting root development and increasing root water absorption area. For Arbor rootstocks, it is suggested that single water conservation measures or superimposed treatment water conservation measures could be selected in the production of Arbor rootstocks, while for dwarfing rootstocks, superimposed water conservation measures could be chosen. |
| Key words: drought stress water retention agent buried brick photosynthesis root system |
