Effect of climate variability on sugarcane breeding in Nigeria
Flowering in sugarcane (Saccharum species) is poor and variable at many tropical locations due to sub-optimal photoperiod. The situation is often compounded by moisture stress with the consequence of poor pollination success from hybridization programmes. This study assessed the impact of variability in weather factors on sugarcane breeding activities of two sugarcane breeding stations in Nigeria. Data showed that the highest pollination success was recorded for crosses (bi-parentals and polycrosses) in 2005 flowering season at Badeggi while none of the fuzz from the two types of crosses was viable in 2007 and 2008 respectively. The difference in pollination success between polycrosses and bi-parentals in 2005 season was 50 percent (%) while that between 2005 and 2006 flowering season for the bi-parentals was 75(%). Seedling mortality was the highest at Ilorin in 2008 and those that survived could not be advanced to the yield testing stage I due to poor morphological characteristics exhibited by the few surviving progenies. The difference between the year with highest pollination success (2007) and other years on this station were 78.96 and 43.35% respectively while that between 2009 and 2008 was 62.29%. We conclude that high temperatures during the ripening period acting singly or in combination with sub-optimal photoperiodism during flowering, was responsible for low viability of fuzz (sugarcane seeds) recorded in both stations in the last three years. Therefore, acquisition of infrastructure to improve flowering by imposing stronger photoperiodic stimuli for initiation, by avoiding high initiation temperatures, or both, along with identification of suitable locations that facilitate making crosses among the best parents available, will lead to attainment of self-sufficiency in sugar production in Nigeria.
Keywords: Climate Change, Variability and Sugarcane Breeding