| 摘要: |
| 【目的】探究施用γ-聚谷氨酸（γ-PGA）对辣椒生长和果实产量的影响,以及其对镉（Cd）胁迫辣椒幼苗的缓解作用，为辣椒高产栽培和Cd污染防治提供理论依据。【方法】以川腾6号辣椒品种为材料，研究叶面喷施0.1 g/L γ-PGA后水培辣椒幼苗生物量和盆栽辣椒果实形态及产量的变化；在0，5和10 mg/L Cd胁迫下，分析施用0.1 g/L γ-PGA后水培辣椒幼苗生长速率、叶绿素含量、抗氧化酶活性、叶绿素荧光特性、矿质元素及镉含量的变化。【结果】喷施γ-PGA可以显著提高辣椒幼苗鲜质量，增加结果数量，使单株产量提高了15.94%。施用γ-PGA显著增加了不同质量浓度Cd胁迫处理辣椒地上部生长速率，其中10 mg/L Cd胁迫处理辣椒的生长速率提高了68.89%。10 mg/L Cd胁迫下，施用γ-PGA能显著提高辣椒幼苗的叶绿素含量，且能使之恢复到未受Cd胁迫时的水平。γ-PGA增加了Cd胁迫辣椒幼苗叶片的最大光化学效率（Fv/Fm）、实际光化学效率（ΦPSⅡ）、电子传递速率（ETR）、光化学淬灭（qP），显著降低了非光化学淬灭（NPQ），有效提高了叶片光能利用率。喷施γ-PGA可以提高Cd胁迫辣椒的SOD、POD、CAT活性，显著提高10 mg/L Cd胁迫处理辣椒植株的Fe、Mn和Zn含量，使Cd吸收降低了19.05%。【结论】叶面施用γ-PGA不仅能有效促进辣椒生长和提高产量，同时可有效缓解Cd胁迫对辣椒的伤害，Cd胁迫越严重，缓解效应越显著。 |
| 关键词: 辣椒 γ-聚谷氨酸 镉胁迫 叶绿素荧光特性 |
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| 基金项目:四川省科技计划项目（2018JY0635）；四川蔬菜花卉种质创新与产业提升关键技术研发专项（2016CYTS-004）；四川省财政创新能力提升工程资源创新和品种培育项目（2016YPZ-023） |
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| Effects of γ-poly glutamic acid on growth and physiological characteristics of pepper under cadmium stress |
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GONG Xuefeng,LI Hong,SONG Zhanfeng,et al
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| Abstract: |
| 【Objective】This study investigated the effects of γ-PGA on growth and fruit yield of pepper and the alleviation of pepper seedlings under cadmium (Cd) stress to provide basis for high yield cultivation and Cd pollution control.【Method】After foliar spraying of 0.1 g/L γ-PGA,changes in biomass of the hydroponic seedlings of hot pepper cultivar ‘Chuanteng No.6’ its and fruit morphology and yield in pots were studied.Under 0,5,and 10 mg/L Cd stress treatments,growth rate,changes of chlorophyll content,antioxidant enzyme activity,chlorophyll fluorescence characteristics,mineral element and Cd content of hydroponic pepper seedlings were further analyzed after foliar spraying of 0.1 g/L γ-PGA using foliar spraying of distilled water as control.【Result】After application of γ-PGA,fresh weight of pepper seedlings and amount of fruit per plant were significantly increased,and yield of fruit per plant was increased by 15.94%.Under different Cd levels,shoot growth rate of pepper with foliar application of γ-PGA was significantly increased.Especially under 10 mg/L Cd,growth rate with foliar application of γ-PGA was increased by 68.89% compared with control.Under 10 mg/L Cd,chlorophyll content was significantly increased and even restored to the level without Cd stress.The γ-PGA application enhanced leaf maximum photochemical efficiency (Fv/Fm),actual photochemical efficiency (ΦPSⅡ),electron transfer rate (ETR),and photochemical quenching (qP) under Cd stress treatments,while significantly reduced non photochemical quenching (NPQ).As a result,it effectively improved utilization of light energy in leaves.After foliar application of γ-PGA,antioxidant enzymes including SOD,POD,and CAT were significantly increased under different Cd levels.The γ-PGA application also resulted in high accumulation of Fe,Mn and Zn in plants under 10 mg/L Cd,and decreased Cd accumulation by 19.05%.【Conclusion】Foliar application of γ-PGA effectively promoted growth and yield of pepper.It also effectively alleviated the damage to pepper caused by Cd stress. |
| Key words: Capsicum annuum L. γ-polyglutamic acid (γ-PGA) cadmium stress chlorophyll fluorescence characteristics |
