低磷诱导下沙棘根系形态构建和光合作用变化  

Morphological Construction and Photosynthetic Changes of Hippophaerhamnoides L.Root System Under Low Phosphorus Induction

作　　者：杨乐 张秀娟[1] 吴楚[1] 涂逸 Yang Le;Zhang Xiujuan;Wu Chu;Tu Yi(College of Horticulture and Gardening,Yangtze University,Jingzhou,Hubei 434025,China)

机构地区：[1]长江大学园艺园林学院,湖北荆州434025

出　　处：《绿色科技》2022年第2期14-17,21,共5页Journal of Green Science and Technology

基　　金：国家自然科学基金面上项目(编号:31971507);青海省科技计划项目(项目批准号:YHZX-2020-07);长江大学植物生态与环境修复研究所课题(编号:201606)。

摘　　要：以沙棘(Hippophae rhamnoides L.)实生幼苗为试材,设置正常供磷170 mg/L(HP)和低磷胁迫0.68 mg/L(LP)两种处理,采用沙培盆栽的方式,探讨了沙棘幼苗对低磷胁迫的响应,分析了沙棘幼苗生物量、根系构型及光合特性的差异。结果表明:低磷胁迫显著(P<0.05)增加了植株的根冠比,高达45%;低磷对幼苗根系的生长发育具有明显的诱导作用,总根长比HP处理下增加18%,表明低磷条件下,根系的生长发育对沙棘幼苗的磷吸收具有重要作用。低磷胁迫降低了沙棘幼苗的光合速率和蒸腾速率,分别为36%和46%;LP处理下,沙棘幼苗叶绿素a、b、a+b比HP处理下分别降低了22%、12.7%、20%。PSⅡ最大光化学效率Fv/Fm和实际光化学效率Y(Ⅱ)比HP处理下分别降低10%和7%;光化学猝灭系数qP和非光化学猝灭量子产量Y(NO)分别比HP处理下增加了1.9%和7%。综上可见,LP处理下,沙棘幼苗通过自身调节,可促进根系生长来应对低磷胁迫。The seedlings of Hippophaerhamnoides L.were used as test materials,and two treatments of normal phosphorus supply of 170 mg/L(HP)and low phosphorus stress of 0.68 mg/L(LP)were set.The response of Hippophaerhamnoides L.seedlings to low phosphorus stress,and the differences in biomass,root architecture and photosynthetic characteristics of Hippophaerhamnoides L.seedlings were analyzed.The results showed that low phosphorus stress significantly ( P <0.05) increased the root-to-crown ratio of the plants by up to 45%. The low phosphorus had a significant induction effect on the growth and development of seedling roots, and the total root length increased by 18% compared with that under HP treatment, indicating that root growth and development under low phosphorus conditions had an important role in phosphorus uptake by H. rhamnoidesL . seedlings. The low phosphorus stress reduced photosynthetic rate and transpiration rate of H. rhamnoidesL . seedlings by 36% and 46%, respectively;chlorophyll a, b, and a + b of H. rhamnoidesL . seedlings were reduced by 22%, 12.7%, and 20%, respectively, under LP treatment compared with under HP treatment. The maximum photochemical efficiency Fv/Fm and actual photochemical efficiency Y(II) of PSⅡ decreased by 10% and 7%, respectively, compared with those under HP treatment;the photochemical burst coefficient qP and non-photochemical burst quantum yield Y(NO) increased by 1.9% and 7%, respectively, compared with those under HP treatment. In conclusion, under LP treatment, Hippophaerhamnoides L . seedlings responded to low phosphorus stress by self-regulating and promoting root growth.

关 键 词：沙棘 低磷 根系形态 光合特性 

分 类 号：S793[农业科学—林木遗传育种]