摘要
研究草莓根系腐解物溶液的化感作用,探讨其对草莓光合机构功能的抑制作用。利用盆栽试验考察5个草莓根系腐解物溶液处理(0.0%,2.5%,5.0%,10.0%,20.0%)对草莓植株的生长发育、叶片气体交换和光系统功能的影响。结果表明:根系腐解物处理对下茬草莓植株叶柄长度、新茎粗度和叶面积有一定抑制作用。处理70d后,草莓植株叶面积分别较对照降低16.3%、18.8%、27.1%和38.8%。随处理浓度增加,根系腐解物明显降低了草莓叶片中叶绿素各组分的含量,提高叶绿素a/b比值;各处理叶片的净光合速率(Pn)分别较对照下降了22.7%、25.3%、43.2%和43.0%,气孔导度(Gs)和胞间CO2浓度(Ci)均受到影响。低浓度根系腐解物溶液处理对草莓叶片的PSⅡ反应中心受体侧电子传递体未产生明显伤害,但高浓度根系腐解物处理对PSⅡ反应中心、放氧复合体(OEC)和PSⅡ受体侧电子受体(QA)均产生伤害,引起PSⅡ最大光化学效率(Fv/Fm)和光化学性能指数(PIABS)下降,但PSI活性(△I/Io)随处理浓度的增加有所提升。可见,草莓根系腐解物引起下茬草莓叶片PSI和PSⅡ光合机构功能下降,影响植株的生长发育,且根系腐解物溶液浓度越大,对草莓植株发育及生理代谢的抑制作用越明显,是造成草莓连作障碍的重要原因之一。
The aim of this experiment was to study the allelopathy effect of decomposed substance of strawberry root and explore its inhibition mechanism of root decomposing products to functions of strawberry photosynthetic apparatus. Potted experiment was conducted to investigate that five concentrations of decomposed substance of strawberry root(0.00%,2.5%,5.0%,10.0% and 20.0%)were usted to study the effects of different decomposed substances on the growth and development of strawberry plants, leaf gas exchange and photosystems functions of strawberry leaves. The results showed that the stalk diameter, petiole length and leaf area of strawberry plants were inhibited by decomposed substance. Compared with control, leaf area of strawberry decreased by 16.3%,18.8%, 27.1% and 38.8%, respectively after treated 70d. With the increasing of root decomposed substance concentration,chlorophyll contents of strawberry leaves decreased significantly, chlorophyll a/b value decreased. The net photosynthetic rate(Pn)decreased by 22.7%, 25.3%, 43.2% and 43.0% companed to control, respectively. Stomatal conductance(Gs)and intercellular CO2concentration(Ci) changed as well. Electron transfer of PSⅡ reaction center acceptor side was not significantly damaged under low concentration treatment, but the PSⅡ reaction center, oxygen-evolving complex(OEC) and the electron acceptora side of PSⅡ(QA) were all harmed under high concentration treatment, which resulted in the decline maximum photochemical efficiency(Fv/Fm)and photochemical performance index(PIABS) of PS Ⅱ. The activity of PSI increased with the increase of root decomposed substance concentration. PS I and PS II photosynthetic apparatus function of strawberry leaves declined when treated with root decomposing products, affecting the growth and development of plants. In addition, the higher of roots decomposing products concentration, the heavier inhibition of the development and physiological metabolism of strawberry plants. In conclusion, root decomposed substance is one of the important reason of strawberry continuous cropping obstacles.
出处
《沈阳农业大学学报》
CAS
CSCD
北大核心
2015年第1期13-18,共6页
Journal of Shenyang Agricultural University
基金
辽宁省教育厅辽教发项目(201036-11)
关键词
草莓
连作
根系腐解物
化感作用
光系统功能
strawberry
continuous cropping
root decomposing products
allelopathy
photosystem functions
