Limitations to photosynthesis under light and heat stress in three high-yielding wheat genotypes

Monneveux, P; Pastenes, C; Reynolds, MP

Abstract

Three high-yielding wheat genotypes (T. aestivum L., c.v. Siete Cerros, Seri and Bacanora, released in 1966, 1982 and 1988, respectively) were grown under irrigation in two high radiation, low relative humidity environments (Tlaltizapan and Ciudad Obregon CIMMYT experimental stations, Mexico). Gas exchange and fluorescence parameters were assessed on the flag leaf during the day. Carbon isotope discrimination (?) was analysed in flag leaf at anthesis and in grain at maturity. In both environments, gas exchange and fluorescence parameters varied markedly with irradiance and temperature. Analysis of their respective variation indicated the occurrence of photo-respiration and photo-inhibition, particularly in Tlaltizapan, the warmest environment, and in Siete Cerros. In Ciudad Obregon (high-yielding environment) lower Ci (internal CO2 concentration) and ?La (carbon isotope discrimination of the leaf) suggested a higher intrinsic photosynthetic capacity in the variety Bacanora. Higher yield of this genotype was also associated with higher Fv?/Fo? (ratio of photochemical and non photochemical rate constants in the light) and Fm?/Fm (ratio of the non photochemical rate constants in the dark and light adapted state).

Más información

Título según WOS: Limitations to photosynthesis under light and heat stress in three high-yielding wheat genotypes
Título según SCOPUS: Limitations to photosynthesis under light and heat stress in three high-yielding wheat genotypes
Título de la Revista: JOURNAL OF PLANT PHYSIOLOGY
Volumen: 160
Número: 6
Editorial: Elsevier GmbH
Fecha de publicación: 2003
Página de inicio: 657
Página final: 666
Idioma: English
URL: http://linkinghub.elsevier.com/retrieve/pii/S0176161704704502
DOI:

10.1078/0176-1617-00772

Notas: ISI, SCOPUS