太阳辐射减弱和O3增加对冬小麦植株磷含量、分配和转运的影响

摘要

采用开顶式气室(OTC)和遮阳网模拟O3增加和地表太阳辐射减弱条件,测定冬小麦不同生育期不同器官的磷含量,并分析O3增加和太阳辐射减弱对植株体内磷含量、分配和转运的影响.结果表明,(1)太阳辐射减弱条件下冬小麦根、茎、叶和穗中磷含量均比自然光条件下显著增加(P＜0.05),根和穗中磷的分配率降低,叶和生育后期茎中磷的分配率增加,植株营养器官中磷的总转运量(P＜0.01)和转运率降低(P＜0.05);(2)100nL·L-1O3处理(T)会增加根、茎、穗和生育后期叶中磷含量,降低乳熟期-成熟期根和穗中磷的分配率,增大成熟期茎和叶中磷的分配率,极显著降低根、茎、叶和营养器官中的磷转运量(P＜0.01),增加叶和营养器官中磷的转运率.(3)O3增加和不同太阳辐射减弱的复合处理均会增加根、茎、叶和穗中磷含量,极显著降低植株根、茎、叶和营养器官中磷的转运量(P＜0.01),降低穗和孕穗期-抽穗期根中磷的分配率(P＜0.05),增加灌浆期-成熟期磷在茎和叶中的分配率(P＜0.05),各复合处理对茎和穗中磷分配率的影响,随着太阳辐射减弱程度的增加而增大,并且在乳熟期-成熟期表现为协同作用.%The experiment was conducted to reveal the effects of the solar radiation attenuation and ozone ( O3 ) concentration increasing on phosphorus concentration, distribution and translocation of winter wheat by using OTCs (open top chambers) and shade-nets in field. The dynamic changes of phosphorus concentration in triticum aestivum different organs were measured in the growing/development (G/D) periods including jointing, booting, heading, filing, milking and mature stages. The results showed that ( 1 ) the concentration of phosphorus were promoted significantly in root, stem, leaf, spike when winter wheat suffered in shadow 20% (SI) , 40% (S2) and 60% (S3) (P <0. 05) , phosphorus distribution rate were reduced in root and spike but increased in leaf and stem (in late growth periods) , the total output ( P < 0. 01 ) and phosphorus transfer rate ( P < 0. 05 ) of nutritorium were both decreased significantly, compared to natural background. (2) Phosphorus concentration in root, stem, leaf (in late growth stages) and spike were promoted respectively under 100nL ·L-1 ozone stress(T) , phosphorus distribution rate of milking ripe and mature stages in root and spike were reduced, but in stem and leaf were increased in the mature stage, phosphorus transfer in root, stem, leaf and nutritorium were debase very significantly ( P < 0. 01) , while phosphorus transfer rate in leaf and nutritorium were increased. (3 ) Winter wheat suffered in shadow cooperate enhanced ozone condition, I. E. 100nL ·l-1 +20% (TS1) , 100nL ·L-1 +40% (TS2) and 100nL·L-1 +60% (TS3) , phosphorus concentration were improved in root, stem, leaf and spike organ, phosphorus transfer volume in root, stem, leaf and nutritoriumrnwere decreased very significantly ( P < 0. 01 ) , phosphorus distribution rate in spike organ and root( during bootingrnand heading stage) ( P < 0. 05 ) were drop, but in stem and leaf were go up in filling to mature stages ( P < 0. 05 ) .rnWith the shadow intensity increased, the effects on phosphorus distribution rate in stem and spike showed growthrntrend, and the reduced solar irradiation and enhanced ozone showed synergy during milking ripe stage and maturernstages.