TAILIEUCHUNG - Báo cáo lâm nghiệp: "Differential photosynthetic and survival responses to soil drought in two evergreen Nothofagus species"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài: Differential photosynthetic and survival responses to soil drought in two evergreen Nothofagus species. | Ann. For. Sci. 64 2007 447-452 INRA EDP Sciences 2007 DOI forest 2007022 Available online at Original article Differential photosynthetic and survival responses to soil drought in two evergreen Nothofagus species Frida I. PlPERa Luis J. C0RCUERAa Miren ALBERDIb Christopher LUSKa c a Departamento de Botánica Universidad de Concepción Edmundo Larenas 1290 casilla 160-C Concepción Chile b Instituto de Botánica Universidad Austral Valdivia Chile c Current address Department of Biological Sciences Macquarie University NSW 2109 Australia Received 21 August 2006 accepted 10 October 2006 Abstract - We asked if differences in distribution between Nothofagus nitida and N. dombeyi were associated with differences in drought tolerance. Survival gas exchange and chlorophyll fluorescence were measured on seedlings subjected to a gradual drought. At a predawn leaf water potential Tm of MPa survival of N. nitida was 50 compared to 100 in N. dombeyi. Under well-watered conditions the two species displayed similar stomatal conductance gw and transpiration E but net photosynthesis A and instantaneous water-use efficiency WUEi were slightly higher in N. nitida. A E and gw declined in N. nitida along the gradual drought but increased in N. dombeyi at a Tm between and MPa and declined then drastically at a Tm below MPa. As N. dombeyi was able to maintain A at higher levels despite declining gw this species displayed significantly increased WUEi at Tm below MPa. Photochemical efficiency of PSII in the light AF Fm and photochemical quenching qP were always lower in N. nitida and along with the photochemical efficiency in the dark Fv Fm they declined in both species. Non-photochemical quenching NPQ increased slowly in N. dombeyi along with the gradual drought whilst it decreased in N. nitida. These results show that differences in drought tolerance are in agreement with sorting of Nothofagus species along moisture gradients in .

• Báo cáo khoa học
• Báo cáo lâm nghiệp hay
• cách trình bày báo cáo
• báo cáo lâm nghiệp
• công trình nghiên cứu lâm nghiệp
• tài liệu về lâm nghiệp