中国农业科学 ›› 2023, Vol. 56 ›› Issue (3): 453-465.doi: 10.3864/j.issn.0578-1752.2023.03.005

• 耕作栽培·生理生化·农业信息技术 • 上一篇    下一篇

施磷对苜蓿叶片生理参数及抗氧化能力的影响

赵建涛(), 杨开鑫, 王旭哲, 马春晖(), 张前兵()   

  1. 石河子大学动物科技学院,新疆石河子 832000
  • 收稿日期:2022-05-20 接受日期:2022-10-08 出版日期:2023-02-01 发布日期:2023-02-14
  • 通信作者: 马春晖,E-mail:chunhuima@126.com。 张前兵,E-mail:qbz102@163.com
  • 联系方式: 赵建涛,E-mail:1513192544@qq.com。
  • 基金资助:
    国家自然科学基金(32001400);霍英东青年教师基金(171099);兵团科技创新骨干人才计划项目(2021CB034);国家现代农业产业技术体系

Effect of Phosphorus Application on Physiological Parameters and Antioxidant Capacity in Alfalfa Leaves

ZHAO JianTao(), YANG KaiXin, WANG XuZhe, MA ChunHui(), ZHANG QianBing()   

  1. College of Animal Science & Technology, Shihezi University, Shihezi 832000, Xinjiang
  • Received:2022-05-20 Accepted:2022-10-08 Published:2023-02-01 Online:2023-02-14

摘要:

【目的】探究连续3年施用磷肥后对紫花苜蓿叶片养分吸收量、光合色素含量、气孔开度及抗氧化系统的影响,为紫花苜蓿高效生产提供科学施肥方法。【方法】2019—2021年,以‘WL366HQ’紫花苜蓿为试验材料,在石河子大学牧草试验站连续开展为期3年的田间试验。试验设置磷肥添加量分别为0(对照,CK)、50 kg·hm-2(低磷,LP)、100 kg·hm-2(中磷,MP)和150 kg·hm-2 (高磷,HP),共4个磷肥处理。于苜蓿初花期进行取样,测定干草产量、叶片氮磷含量、色素含量、气孔开度、抗氧化酶活性以及氧化物质等指标。【结果】连续施加磷肥3年后,叶片的氮磷含量、光合色素含量及气孔开度显著增加(P<0.05),其中叶片氮磷含量在中磷处理下最高,分别为54.74和2.99 g·kg-1;叶绿素a和叶绿素b的含量均在中磷处理下最高,类胡萝卜素含量在低磷或中磷处理下最高,且均在CK最低;气孔开度在中磷处理下达到最大,且显著高于CK(P<0.05)。因此,磷肥对苜蓿叶片的形态和生理特性有不同的影响,且中磷处理显著影响苜蓿叶片的光合生理特性(P<0.05)。合理添加磷肥可以提高苜蓿叶片抗氧化酶的活性并降低氧化物质的含量,超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性均在中磷处理达到最高,分别为162.55、406.40和147.13 U·g-1,且显著高于CK(P<0.05);丙二醛(MDA)、过氧化氢(H2O2)和脯氨酸(Pro)含量均在中磷处理下最低,分别为2.38和1.04 μmol·g-1以及56.85 μg·g-1。根据Pearson相关性分析可知,苜蓿叶片全氮和全磷含量与叶绿素含量、类胡萝卜素含量、气孔开度、SOD和POD活性显著正相关(P<0.05),与MDA和H2O2含量呈显著负相关(P<0.05)。综合评价表明,施磷处理的主成分得分排序为:中磷>高磷>低磷>对照。【结论】合理施加磷肥增加苜蓿叶片的营养特性及光合生理特性,从而避免其他环境因子带来的胁迫作用,增强苜蓿的适应能力,使苜蓿更好地适应外界环境变化。综合考虑紫花苜蓿的叶片形态、光合生理特性及抗氧化酶和氧化物质等因素,本试验施磷量为100 kg·hm-2较为适宜。

关键词: 紫花苜蓿, 施磷, 叶片表型, 叶片生理, 干草产量

Abstract:

【Objective】The aim of this study was to investigate the effects on nutrient uptake, photosynthetic pigment content, stomatal aperture and antioxidant system of alfalfa leaves after three consecutive years of phosphorus fertilizer application, so as to provide scientific fertilization methods for efficient production of alfalfa.【Method】Field trials were conducted at the forage experiment station of Shihezi University in Xinjiang from 2019 to 2021. ‘WL366HQ’ alfalfa was used as the test material, and four fertilizer treatments in the experiment included 0 (CK), 50 (Low P, LP), 100 (Middle P, MP), and 150 (High P, HP) kg·hm-2. Samples were taken at the first flowering of alfalfa to determine the hay yield, nitrogen and phosphorus content, pigment content, stomatal opening, antioxidant enzyme activity, and oxidizing substances of leaves.【Result】The nitrogen and phosphorus content, photosynthetic pigment content and stomatal aperture of leaves of alfalfa increased significantly (P<0.05) after 3 years of continuous phosphorus fertilization, with the highest nitrogen and phosphorus content under MP treatment (54.74 and 2.99 g·kg-1, respectively), the highest chlorophyll a and chlorophyll b content under MP, and the highest carotenoid content under LP or MP, and the lowest in CK. The stomatal aperture was the highest under MP and significantly higher than that under CK (P<0.05). Therefore, phosphorus fertilizer had different effects on the morphological and physiological characteristics of alfalfa leaves, and MP treatment significantly affected the photosynthetic and physiological characteristics of alfalfa leaves (P<0.05). Superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities were the highest under MP, with the value of 162.55, 406.40 and 147.13 U·g-1, respectively, and were significantly higher than those under CK (P<0.05). The malondialdehyde (MDA), hydrogen peroxide (H2O2) and proline (Pro) content were the lowest under MP, at 2.38 and 1.04 μmol·g-1 and 56.85 μg·g-1, respectively. According to the Pearson correlation analysis, the total N and P contents of alfalfa leaves showed significant positive correlation (P<0.05) with chlorophyll content, carotenoid content, stomatal aperture, SOD activity and POD activity, and significant negative correlation (P<0.05) with MDA and H2O2 content. The overall evaluation showed that the principal component scores of phosphorus application treatments were ranked as MP>HP>LP>CK. 【Conclusion】 The reasonable application of phosphorus fertilizer increased the nutritional characteristics and photosynthetic physiological characteristics of alfalfa leaves, thus avoiding the stressful effects brought by other environmental factors, enhancing the adaptive capacity of alfalfa, and making it better adapted to external environmental changes. Considering the leaf morphology, photosynthetic physiological characteristics and antioxidant enzymes and oxidizing substances of alfalfa, the phosphorus application rate of 100 kg·hm-2 was suitable under this experiment.

Key words: alfalfa, phosphorus fertilizer, leaf phenotype, leaf physiology, hay yield