CAJ | 학술논문

在苗木生长的不同时期对13个毛白杨(Populus tomentosa)杂种无性系叶片碳同位素δ~(13)c和气体交换参数(净光合速率P_n、蒸腾速率T_r、瞬时水分利用效率WUE_I、气孔导度G_s和胞间CO_2浓度C_I)的差异进行研究,分析不同无性系间δ~(13)C与气体交换参数的相互关系,目的在于探求δ~(13)C在筛选高光合及高水分利用效率毛向杨杂种无性系中的应用价值.结果表明:不同生长时期和小同无性系问δ~(13)>C、T_r、WUE_I、G_s和G_I的差异均显著,δ~(13)C和WUE_I表现为9月>7月,T_r、G_s和C_I表现为7月>9月,P_n在不同生长时期差异不显著.季节变化是引起毛白杨杂种无性系叶片δ~(13)C差异的主要原因.同一时期,无性系间δ~(13)C和WUE_I表现出较好的一致性,即WUEi较高的无性系30、42、46、83、BL2和BL5,其δ~(13)C值也较高,WUEi较低的无性系B331和TG34,其δ~(13)C值也较低,且不同时期(7月和9月)δ~(13)C和WUE_I呈较强的正相关,相关系数r分别为0.739 0和0.545 8,高δ~(13)C可以作为筛选高WUE_I毛白杨的有效指标,且在苗木生长旺盛时期选育能得到更为可靠的结果.对毛白杨而言,高WUEi的无性系,一般具有适中或较低的G_s和G_I,但不一定具有很高的P_n,气孔调节使得毛白杨在不影响光合作用的同时保持较高的WUE.
재묘목생장적불동시기대13개모백양(Populus tomentosa)잡충무성계협편탄동위소δ~(13)c화기체교환삼수(정광합속솔P_n、증등속솔T_r、순시수분이용효솔WUE_I、기공도도G_s화포간CO_2농도C_I)적차이진행연구,분석불동무성계간δ~(13)C여기체교환삼수적상호관계,목적재우탐구δ~(13)C재사선고광합급고수분이용효솔모향양잡충무성계중적응용개치.결과표명:불동생장시기화소동무성계문δ~(13)>C、T_r、WUE_I、G_s화G_I적차이균현저,δ~(13)C화WUE_I표현위9월>7월,T_r、G_s화C_I표현위7월>9월,P_n재불동생장시기차이불현저.계절변화시인기모백양잡충무성계협편δ~(13)C차이적주요원인.동일시기,무성계간δ~(13)C화WUE_I표현출교호적일치성,즉WUEi교고적무성계30、42、46、83、BL2화BL5,기δ~(13)C치야교고,WUEi교저적무성계B331화TG34,기δ~(13)C치야교저,차불동시기(7월화9월)δ~(13)C화WUE_I정교강적정상관,상관계수r분별위0.739 0화0.545 8,고δ~(13)C가이작위사선고WUE_I모백양적유효지표,차재묘목생장왕성시기선육능득도경위가고적결과.대모백양이언,고WUEi적무성계,일반구유괄중혹교저적G_s화G_I,단불일정구유흔고적P_n,기공조절사득모백양재불영향광합작용적동시보지교고적WUE.
Aims Fast, efficient breeding of fast-growth and high water use efficiency (WUE)in Populus tomentosa clones is a pressing need for afforestation in arid and semi-arid regions. There is much research on the correlation be-tween stable carbon isotope and WUE in crops and a few trees, but little in different clones of P. tomentosa. Our objective was to explore the application of δ~(13)C on selection of clones with high photosynthesis and WUE.Methods We examined 13 clones of Populus-grafted seedlings in Beijing Forestry University (39°46' N, 116°19'E)Nursery in Beijing, China. We studied leaf δ~(13)C of the seedlings by MAT-251-MS in two different growth pe-riods (mid-July and September)and gas exchange parameters (net photosynthetic rate (P_n), transpiration rate (T_r),instantaneous water use efficiency (WUE_i), stomatal conductance (G_s)and intercellular CO_2 concentration (C_i))by LI-6400 portable photosynthesis system between 9:30 and 11:30 a.m. in the same periods. Important findings Leafδ~(13)C, T_r, WUE_i, G_s and C_i significantly differed between the periods and among clones. Leaf δ~(13)C and WUE_i were higher in July than September; however, T_r, G_s and C_i were lower in July than Septem-ber and Pn showed no significant difference between periods. The main reason for the difference of leaf δ~(13)C was seasonal variation. Leaf δ~(13)C and WUEi of the clones were consistent during the same period, i.e, the higher WUE_i appeared in clones of 30, 42, 46, 83, BL2 and BL5 with higher δ~(13)C and the lower WUE_i occurred in clones of B331 and TG34 with lower δ~(13)C. There was strong positive correlation between δ~(13)C and WUE_i (r = 0.739 0 and 0.545 8 in July and September, respectively); therefore, high δ~13C can be used as an effective indicator of high WUE_i in Populus. Clones with higher WUE_i may have moderate or low G_s and C_i, but not necessarily high P_n.