干旱胁迫下CoCl_2对辣椒幼苗生长及部分生理特性的影响

Effect of CoCl_2 on growth and physiological characteristics of pepper seedlings under drought stress

【目的】研究中度干旱（60%田间持水量）下,缓解辣椒幼苗干旱胁迫的适宜的CoCl2溶液浓度.【方法】以‘陇椒5号’辣椒为试材,采用不同浓度CoCl2（0.02、0.04、0.06、0.08、0.10、0.12mmol/L）溶液浇灌处理,并测定处理期间辣椒幼苗相关生长生理指标.【结果】随着CoCl2浓度的增加,辣椒幼苗株高、茎粗、地上部干质量、根冠比呈先增大后减小的趋势,均在0.06~0.08mmol/L处理时出现峰值;CoCl2浓度在0.06mmol/L以上时可显著促进叶片中叶绿素含量的增加;0.06~0.10mmol/L CoCl2处理辣椒幼苗叶片丙二醛和脯氨酸含量显著低于单一干旱胁迫处理;高浓度的CoCl2（0.10~0.12 mmol/L）处理,对地下部干物质的积累和根系的伸长有显著的抑制作用.【结论】综合各项生长及生理指标,外源施用0.06~0.08mmol/L CoCl2可缓解辣椒幼苗干旱胁迫.

【Objective】To determine suitable solution concentration of CoCl2 to reduce the moderate drought stress（60%field moisture capacity）.【Method】‘LongJiao 5＇was used as test material to be irrigated with the following concentrations of CoCl2solution（0.02,0.04,0.06,0.08,0.10,0.12mmol/L）and determined growth and physiological indicators of pepper seedlings during processing.【Result】With the increase of CoCl2 concentrations,plant height,stem diameter,shoot dry weight,shoot ratio of pepper seedling increased first then decreased,and the peak values all occurred at the concentration range of 0.06~0.08mmol/L.CoCl2 concentration more than 0.06mmol/L significantly promoted the increase of chlorophyll content.MDA and proline content in pepper seedling leaves treated with 0.06~0.08mmol/L CoCl2 than those under single drought stress（CK1）.High concentrations of CoCl2（0.10~0.12mmol/L）significantly inhibited the underground dry matter accumulation and root elongation.【Conclusion】Based on comprehensive analysis on various growth and physiological indicators,exogenous application of 0.06~0.08mmol/L CoCl2 solution can alleviate drought stress on pepper seedlings.