低温弱光胁迫下辣椒苗期光合相关指标的杂种优势

为筛选可用于鉴定和预测辣椒杂种优势的光合指标,利用隶属函数值、灰色关联法和相关性分析法分析了低温弱光胁迫对辣椒亲本及其杂交种F₁苗期叶片净光合速率(P_n)、气孔导度(G_s)、胞间二氧化碳浓度(C_i)、蒸腾速率(T_r)和叶绿素含量的影响。结果表明:预测辣椒杂种优势的光合指标优劣顺序是C_i>G_s>叶绿素含量>T_r>P_n;低温弱光胁迫下,离中优势和超亲优势是评价辣椒杂种优势的优良度量标准; 3种辣椒材料的耐低温弱光能力大小为杂交种F₁>父本>母本。此研究丰富了辣椒杂种优势理论,为合理选用辣椒杂种优势鉴定标准、预测辣椒杂种优势提供了理论依据。

Heterosis analysis of photosynthetic parameters of pepper seedling responding to low temperature and low light stress

In order to screen the photosynthetic parameters for identifying and predicting the heterosis of pepper, using the parents and their F₁ hybrid of pepper as materials, effects of low temperature and low light on net photosynthetic rate (P_n), stomatal conductance (G_s), intercellular carbon dioxide concentration (C_i), transpiration rate (T_r) and chlorophyll content of pepper seedlings were comprehensively analyzed by the method of subordinate function values, grey correlation and correlation analysis. The results showed that the order of photosynthetic parameters to predict the heterosis of pepper from high to low was C_i, G_s, chlorophyll content, T_r and P_n. In addition, superiority from mid-parent heterosis and super-parent heterosis were chosen as the most suitable standards for appraising heterosis of pepper under low temperature and low light stress. The order of low temperature and low light resistance of the three materials was F₁ hybrid>male parent>female parent. This study enriched the heterosis theory of pepper, and provided theoretical basis for selecting photosynthetic parameters to predict the heterosis of pepper.