Sugarcane for water-limited environments. Genetic variation in cane yield and sugar content in response to water stress

Abstract

Water limitation is a major production constraint for sugarcane worldwide. However, to date, there has been little investigation of patterns of genetic variation in the response to water stress in sugarcane. Field experiments were conducted over 3 years under fully irrigated and managed water stress conditions at two locations in Northern Queensland in Australia. Eighty-nine genetically diverse clones were evaluated for their yield performance and sugar attributes. Water stress treatments reduced cane yield [tonnes of cane per hectare (TCH)] and total dry matter (TDM) by 17-52% and 20-56%, respectively, compared with irrigated treatments in the same experiments. Nevertheless, there was little genotype×environment interaction variation for TCH, TDM, or commercial cane sugar (CCS), and hence high genetic correlations between the irrigated and water stress treatments across environments. Both commercial and unselected clones performed poorly under severe stress environments, while the commercial clones outperformed the unselected clones under mild and moderate stress conditions. The results presented here highlight the contribution of intrinsic potential yields (yield under well-irrigated conditions) of some selected and unselected clones to maintain relatively high productivity in a range of moderate stress conditions imposed. The physiological basis for the high genetic correlations is at present unclear, but some explanations are hypothesized. The choice of stress levels in selection trials would not appear to be a critical issue for sugarcane breeding programmes, at least for the early phases of selection, where similar ranking clones across a range of moderate water stresses may be expected.

Gestión del agua como factor limitante de productividad cañera en México

“…Esta respuesta espectral responde a la humedad disponible en suelo y se refl eja en el vigor vegetal. Por tanto, el análisis de la productividad derivada del agua que recibe el cultivo como precipitación pluvial, durante sus distintas etapas fenológicas corresponde al factor climático que más limita la productividad de acuerdo a las conclusiones de Da Silva et al (2013); Basnayake et al (2012); Wiedenfeld (2000) y las revisiones de Carr & Knox (2011) y Lopes et al (2011.…”

Conditional up-regulation of cytokinin status increases growth and survival of sugarcane in water-limited conditions

“…Drought tolerance is one of the priority research areas in major agribusiness companies. As with the broadacre crops, substantial research effort is currently underway in developing drought tolerant sugarcane via transgenic and conventional strategies (Basnayake et al, 2012, Lakshmanan andRobinson, 2014).…”

“…Thus, constitutive up-regulation of CK production is undesirable from a crop yield perspective. In Australia, commercial sugarcane crops experience two reasonably long periods of water stress, about 3 months before and after the (generally) rainy summer, during the 12-month crop cycle (Basnayake et al, 2012). Hence, for crop improvement a logical approach would be to increase CK production during stress periods by bringing IPT transgene expression under the control of a stressinducible promoter.…”

“…These physiological traits are directly or indirectly associated with crop growth and yields (Silva et al, 2007, Wilkinson et al, 2012. There are reports that there is genetic variation for water stress responses and yield among sugarcane varieties (Basnayake et al, 2012). Information on drought response of new cultivars is generally obtained from commercial production experiences, and indeed only a few genotypes have been evaluated extensively for drought response .…”

“…Per Drop" in 2006(Basnayake et al, 2012. The project aimed to advance understanding of the morphological and physiological responses of sugarcane under water-limited growth conditions to identify traits that improve crop productivity under well-watered and water-deficit conditions.…”