Season effects on leaf nitrogen partitioning and photosynthetic water use efficiency in mango

• Published in: Journal of plant physiology 2006-01, Vol.163 (1), p.48-57
• Main Authors: Urban, Laurent, Montpied, Pierre, Normand, Frédéric
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; carbohydrate content; carboxylation; cell respiration; Climate; Crops, Agricultural; Economic plant physiology; electron transport chain; Flowering; Fruiting; Fundamental and applied biological sciences. Psychology; Leaf nitrogen; Life Sciences; Mangifera - metabolism; Mangifera indica; Mangifera indica L; mangoes; Nitrogen - metabolism; Non-structural carbohydrates; photosynthesis; Photosynthesis - physiology; Photosynthetic capacity; Phytopathology and phytopharmacy; plant biochemistry; Plant Leaves - metabolism; Respiration; seasonal variation; Seasons; Stomatal conductance; tree physiology; Vegetal Biology; Water - metabolism; Water relations, transpiration, stomata; Water use efficiency
• ISSN: 0176-1617; 1618-1328
• DOI: 10.1016/j.jplph.2005.02.005

The key parameters of photosynthetic capacity (maximum carboxylation rate ( V cmax ), electron transport capacity ( J max ) and dark respiration rate ( R d )) and the slope ( m ) of the stomatal conductance model of Ball et al. [Progress in photosynthetic research, Martinus Nijhoff, Dordrecht, 1987] were measured for a whole growing season in fully expanded leaves of 12-year-old mango trees cv. Cogshall in La Réunion island. Leaf nitrogen partitioning into carboxylation ( P c ) and bioenergetic ( P b ) pools were computed according to the model of Niinemets and Tenhunen [Plant Cell Environ 1997;20: 845–66]. V cmax , J max , R d , P c and P b remained relatively stable over the whole study period, with the exception of the period of linear fruit growth when J max , R d and P b were slightly lower, and leaf non-structural carbohydrate content higher. During the pre-floral and floral periods, m decreased by more than 50%, indicating an increase in photosynthetic water use efficiency and m increased again during the period of linear fruit growth. Our results show that, in tropical orchard conditions characterized by mild seasonal climatic changes and non-limiting water supply, leaf nitrogen partitioning is rather stable. Our results also advocate for more studies on the effect of phenology on m and photosynthetic water use efficiency, which is of paramount importance for building coupled biochemical models of photosynthetic carbon assimilation.