Sugarcane Breeding, Germplasm Development and Supporting Genetics Research in Thailand

Thailand is currently ranked as the world’s fourth largest sugarcane producer after Brazil, India and China and the world’s second largest sugar exporter after Brazil. In the past five years (2015–2020), average sugarcane yield in Thailand was around 63 tonnes/hectare, with an average commercial cane sugar (CCS) content of 12.41%. An estimated 330,000 sugarcane growers are now cultivating sugarcane in Thailand. In the 2017/18 milling season, crop production reached a peak of 134.9 million tonnes of sugarcane with 1.58 million hectares of cultivated area. However, the production has since shown a declining trend due to recurring drought and a shift in farmers’ preference for more profitable crops. Since its inception in 1938, sugarcane breeding has continuously increased the cane productivity by releasing improved varieties with the most notable one, Khon Kaen 3 (KK3), which now covers ~85% of the sugarcane production in Thailand. To continue improve the productivity and sustainability of the Thailand sugar industry, current breeding programs are mainly focusing on cane yield and sugar content, with increasing emphasis on fiber yield, pest and disease resistance, environmental adaptability (e.g., sandy soil, clay soil, drought conditions), ratooning ability and suitability for mechanical harvesting. The development and integration of biotechnology will no doubt contribute to further improvement of desirable traits. This review covers the main characteristics of the national sugar industry, key institutions currently involved in breeding and its supporting research, history and achievements of sugarcane breeding programs, current methods used in breeding programs as well as major cultivars and germplasm collections. The history and current status of the research and application of genetics and biotechnology for sugarcane improvement are also presented.