Simulation of the maximum yield of sugar cane at different altitudes: effect of temperature on the conversion of radiation into biomass.

摘要

The temperature-solar radiation interaction was investigated in relation to sugarcane growth in La Reunion. A model of sugarcane growth was fitted to the results from two contrasting sites (altitudes 150 and 780 m: mean temperatures: 14-30deg C; totalradiation: 10-25 MJ m-2 day-1), on a ratoon crop of cv. R570, under conditions of non-limiting resources. Radiation interception, aerial biomass, the fraction of millable stems, and their moisture content, were measured. The time-courses of the efficiency of radiation interception differed between sites, but they were similar as a function of the sum of day-degrees. The dry matter radiation quotient was related to temperature. The moisture content of millable stems depended on the day-degree sum, whilethe leaf/stem ratio was independent of temperature. The relationships established enabled the construction of a simple model of yield potential. Applied to a set of sites representing the sugarcane growing area of La Reunion, it gave a good prediction ofmaximum yields.