
Water deficit tolerance in sugarcane is dependent on the accumulation of sugar in the leaf
2019; Wiley; Volume: 176; Issue: 1 Linguagem: Inglês
10.1111/aab.12559
ISSN1744-7348
AutoresFernando Henrique Silva Garcia, Ane Marcela das Chagas Mendonça, Marcelo Rodrigues, Filipe Inácio Matias, Mário P. da Silva Filho, Hugo Rafael Bentzen Santos, Julian Taffner, J. P. R. A. D. Barbosa,
Tópico(s)Plant responses to water stress
ResumoAbstract Sugarcane productivity is severely affected by the occurrence of water deficit in the field, causing inhibition of growth and sugar production. Evaluating physiological responses of sugarcane under water deficit conditions is essential to understand physiological variables responsible for reaching homeostasis. Therefore, we analysed physiological traits of two sugarcane genotypes, RB835486 (Tolerant) and RB855453 (Susceptible), under water deficit conditions: well‐watered (WW‐Control), water deficit (WD) and rewatered (RW). The physiological response was evaluated using linear regression and multivariate analysis. Some characteristics such as water potential in leaves, photosynthesis, chlorophyll fluorescence, chlorophyll index, sucrose and starch contents did not show differences between the genotypes under water deficit conditions. However, the tolerant genotype showed increased reducing sugars content in the leaves, whereas the susceptible genotype had increased non‐photochemical quenching ( qN ). After rewatering, the susceptible sugarcane genotype showed higher electron transport rate ( ETR ) and efficiency of PSII ( Y ). Multivariate analysis revealed that non‐photochemical quenching and reducing sugars in the leaves were physiological variables responsible for reaching homestasis under water deficit conditions. Therefore, the reducing sugars concentration should be considered a physiological variable responsible for the adjustment made by the tolerant sugarcane genotype when submitted to water deficit.
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