SEASON EFFECTS ON PRODUCTIVITY OF SOME COMMERCIAL SOUTH AFRICAN SUGARCANE CULTIVARS, I: BIOMASS AND RADIATION USE EFFICIENCY

Abstract

There is renewed interest in ethanol production, and sugarcane promises to be a sustainable ethanol source. Few studies have been done on the effect of season on biomass production, and no studies have quantified yields of a range of cultivars in terms of intercepted radiation. The objective of this study was therefore to assess how season affects the biomass yields of a number of commercial cultivars. The above-ground biomass was measured in two experiments at Pongola and Mount Edgecombe. The treatments consisted of nine cultivars in each experiment and two or five crop starting dates. Season had a large influence on biomass yield production for all cultivars, with some cultivars being more adversely affected than others. Biomass yields of December crops were substantially lower than autumn/winter crops, particularly for cultivars N22 and CP66/1043. Cultivars N14, N16 and N21 were least affected by the conditions that have an adverse effect on December yields and could possibly be more stable cultivars to consider for ethanol production than some of the other cultivars assessed in this study.