外源氯化钙对低温胁迫下胡椒抗寒生理指标的影响

以中国胡椒主栽品种‘热引1号’胡椒为材料,设置4个不同浓度氯化钙（7、14、21、28 mmol/L）处理,以去离子水为对照,低温胁迫4 d（10 ℃/5 ℃,12 h/12 h）,恢复培养6 d（28 ℃/20 ℃,12 h/12 h）,观察表型并测定各处理的光合参数、抗氧化酶活性及渗透性物质含量变化情况。结果表明：7 mmol/L氯化钙处理胡椒可以改善寒害表型,随氯化钙浓度升高寒害表型逐渐加重;外施7 mmol/L氯化钙能够显著改善胡椒的净光合速率,随氯化钙浓度升高,净光合速率越来越低,氯化钙浓度过高时（达到28 mmol/L）净光合速率低于CK;与CK相比,外施7 mmol/L氯化钙能够显著提高抗氧化酶活性、增加可溶性糖含量、降低丙二醛含量。随处理浓度升高,抗氧化酶活性和可溶性糖含量越来越低,丙二醛含量越来越高。本研究结果为胡椒生产上抗寒技术指导和抗寒分子育种提供了参考。

Effects of Exogenous Ca 2+ on Leaf Physiological Indexes in Black Pepper Under Low Temperature Stress

Piper nigrum cv. Reyin1 is widely planted in China and is sensitive to cold stress. Five different concentrations of calcium chloride treatments including 0, 7, 14, 21, 28 mmol/L were set to spray black pepper. All the materials were treated with low temperature (10 ℃/5 ℃, 12 h/12 h) for four days and recovery training (28 ℃/20 ℃, 12 h/12 h) for six days. The phenotype and physiological indexes were analyzed. Calcium chloride treatment of 7 mmol/L could improve the cold damage phenotype and net photosynthetic rate of black pepper. With Ca ²⁺ concentration increasing, the cold damage phenotype gradually aggravated and net photosynthetic rate became lower. Compared with CK, the 7 mmol/L Ca ²⁺ treatment could significantly improve the activity of antioxidant enzymes, increase the soluble sugar content and reduce the malondialdehyde content. With the Ca ²⁺ treatment concentration increasing, the activity of antioxidant enzymes and the soluble sugar content became lower, and the malondialdehyde content became higher. The results would provide a reference for cold resistance technical guidance and cold resistance molecular breeding in black pepper production.