低温驯化对木薯耐寒性形态、生理特性的影响

Effects of Cold Acclimation on Morphological,Physiological Characteristics of Cassava(Manihot esculenta Crantz)

用相对耐寒的2个木薯品种华南124和Arg7为材料,设置14℃弱低温驯化后4℃伤害处理、非驯化直接4℃处理和25℃对照,观察和测定了木薯在低温驯化处理下的形态与生理变化。结果表明,该2个品种经低温驯化处理后比非驯化处理,植株形态损伤减轻,恢复正常温度后形态恢复力增强;叶片中的叶绿素含量下降延缓、脯氨酸含量增幅高而丙二醛含量指示的细胞膜破损变小;而在温度恢复过程中叶绿素含量、叶片脯氨酸含量增加均较快。形态与生理指数一致表明,弱低温驯化能够有效提高木薯对低温的适应能力及恢复能力。

Double cassava varieties Southern China 124 and Arg 7 with higher tolerance to coldness were used in cold acclimation experiments under 4 treatments AT （acclimation treatment）, AH （acclimation hurt）, NAH （non-acclimation hurt） and NC （negative control）. The morphological and physiological responses showed that cold acclimation decreased damage of leave in stress and increased the morphological restoration ability after the stress. The chlorophyl lost were minimized, proline content significant increased and the content of malondialdehyde which of indicator of broken membrane was not so high compared to un-acclimation treat. Meanwhile, the chlorophyl and praline increasing were faster than check during the process of restoration at normal temperature. This experiment identified that cold acclimation could enhance tolerance to cold stress and recovery capability of cassava. How to explore the molecular genetic mechanism of the acclimation by lower temperature stress was discussed in the paper.