保水剂对水分胁迫下辣椒生长及光合作用的影响

以‘超越5号’辣椒品种为试材,研究了中度水分胁迫10d和20d及随后分别复水的过程中保水剂对始花期辣椒植株的生长量、叶绿素以及光合特性的影响。结果显示:(1)水分胁迫显著抑制了辣椒植株的生长、叶绿素含量以及光合作用。(2)添加2‰的保水剂显著提高了水分胁迫下植株的株高、茎粗、干鲜重、叶绿素含量以及净光合速率、胞间CO2浓度、气孔导度和蒸腾速率等光合参数,降低了气孔限制值和水分利用率。(3)保水剂能够显著缓解短时间内中度水分胁迫造成的伤害,但随着胁迫时间的延长保水剂缓解的效果有限。(4)复水后,添加保水剂的植株生长量、叶绿素含量以及光合参数都显著高于未添加保水剂的植株,同时短时间胁迫下恢复的效果明显好于长时间胁迫的效果。研究表明,施加保水剂能通过提高叶绿素含量,缓解水分胁迫对辣椒叶片气孔的限制,从而提高叶片的光合作用效率,促进辣椒植株的生长,且胁迫时间越短,保水剂缓解的效果越好。

Effects of Superabsorbent Polymers (SAP) on Growth and Photosynthesis of Pepper Plants under Water Stress

Effect of superabsorbent polymers(SAP) on the growth and chlorophyll content of leaves,as well as the photosynthesis was conducted with pepper variety ’Chaoyue No.5’in flowering stage under 10 days and 20 days medium water stress and the subsequent recovery process.The results showed that:(1)Water stress inhibit the growth mass,chlorophyll content and photosynthesis.(2)Adding 2‰ of SAP significantly decreased Ls,WUE,significantly increased the plant height,stem diameter,dry fresh weight,chlorophyll content,and Pn,Ci,Gs,Tr under the water stress.(3)Under moderate water stress SAP can significant mitigate this damage in a short period of time,while the effect of SAP is limited with the time.(4)When resumed the normal water supply,the plant growth,chlorophyll content and photosynthetic parameters were significantly higher with SAP than that without SAP,while the recovery effect under short time stress was significantly better than that under long time stress.It indicates that SAP treatment could increase photosynthetic parameters,improve the growth and relieve the water stress of damage on pepper by increasing the content of chlorophyll,and with the shorter time of water stress,the better effect of the SAP.