ECOPHYSIOLOGICAL BASES OF YIELD AND RESOURCE USE EFFICIENCY AS AFFECTED BY SUGARCANE BREEDING IN ARGENTINA

ACRECHE M.M.; CHALCO VERA J.E.; SÁEZ J.V.

Congreso; XXXI Reunión Argentina de Fisiología Vegetal; 2016

The analysis of the trends of sugar yield (SY) worldwide reveals that the rate of increase of it has been actually slowing down since the 1980s. This study aimed to identify whether and how sugarcane breeding in Argentina modified the ecophysiological bases associated to yield, and to nitrogen, water and radiation use efficiencies. Thirteen varieties were grown during three consecutive crop cycles at Tucumán, Argentina. There was a linear increase in SY, cane yield (CY), sugar content (SC), average stem weight (ASW), total dry matter (TDM), nitrogen use efficiency (NUE) and water use efficiency (WUE) with the year of release of the varieties. SY was associated with CY, SC, ASW, TDM, NUE and WUE (r> 0.65; P< 0.05), whereas CY was only related to TDM, ASW, NUE and WUE (r> 0.81; P< 0.01). SY and CY were not related to the number of stems, which was not increase by breeding. Although sugarcane breeding did not increase the radiation use efficiency, it increased the amount of radiation intercepted by the crop during it cycle. Breeding also modified the dynamic of interception of the radiation: modern varieties had higher maximum interception and needed fewer days to reach maximum interception than old varieties.