Evander Alves Ferreira, Ignacio Aspiazú, Germani Concenço, Alexandre Ferreira Silva, Antonio Alberto Silva, Leandro L Galon, Daniel Valadão Silva



The objective of this work was to evaluate physiological characteristics of sugar cane genotypes, as well as characterize them in groups according to their similarity, checking the ability of ecological adaptability of these genotypes. The work was performed in field conditions, being assessed ten sugarcane genotypes (RB855113, RB835486, RB867515, SP80-1816, RB72454, RB925345, RB855156, RB937570, RB947520 and RB925211) in a randomized block design with three repetitions. It were evaluated the stomatal gas flow rate (U - μ mol s-1), the concentration of under-stomatal CO2 (Ci - μmol mol-1), the photosynthetic rate (A - μmol m-2 s-1), the CO2 consumed (Δ C - μmol mol-1), the stomatal conductance (Gs - mol m-1 s-1), the temperature gradient between leaf and air (Δ T), and the transpiration rate  (E - mol H2O m-2 s-1), being also calculated the water use efficiency (WUE - mol CO2 mol H2O-1) from the values of the amount of CO2 fixed by photosynthesis and amount of water transpirated. Both univariate and multivariate data analysis were made. The genotype SP80-1816 showed better water use efficiency, combined with low stomatal conductance and transpiratory rate. The cultivar RB855113 stood out by having high photosynthetic rate, and high consumption of CO2. The cultivar RB867515, in addition to showing high water use efficiency, also showed high photosynthetic rate. With respect to the multivariate analysis, the biotypes RB925345, RB925211, RB855156 and RB855113 are situated in different groups when compared to the others as to the physiological characteristics with respect to other genotypes with isolation in separate groups.

Keywords: Saccharum spp. photosynthesis. Transpiration. Cultivars.


Saccharum spp; Photosynthesis; Transpiration; Cultivars

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DOI: http://dx.doi.org/10.0000/rtcab.v5i3.87

Direitos autorais 2011 Revista Trópica: Ciências Agrárias e Biológicas

Licença Creative Commons
Este obra está licenciado com uma Licença Creative Commons Atribuição-NãoComercial-SemDerivações 4.0 Internacional.

R. Tróp.: Ci. agr. biol.

ISSN 1982-4831