Résumé
Many farmers in Thailand grow sugarcane under contract farming, which is a potential system to support sugarcane product management from farm to sugar factory. Contract farming system has potential advantages to both farmers and agribusiness companies. The farmers receive input support, production services, credit support, appropriate technology, skill transfer and guaranteed and fixed pricing from agribusiness companies. Agribusiness companies that make the contract with farmers have ensured product and receive quality product. Two major problems of sugarcane production under contract farming in Thailand are low yield and low quality which is dependent on production practice. The objective of this research was to investigate the influence of different production factors on cane yield and commercial cane sugar level of sugarcane grown under contract farming system in Thailand. The data were collected from a farm survey through individual interview of contract sugarcane farmers from three sugar mills located at Lopburi, Saraburi and Nakhon Sawan Provinces, Thailand. A total of 270 farmers belonging to small, medium and large farm sizes were selected. The results showed that irrigation, chemical fertilizer application and farm size significantly influenced cane yield and accounted for 82 % of the variation in yield. Timely delivery from farm to sugar mill and crop age of sugarcane during harvesting were the factors significantly related to the quality of sugarcane product typically measured by commercial cane sugar value and accounted for 71.8 % of the variation in sugarcane quality. Good management practice in sugarcane farm is important to increase yield and commercial cane sugar level. Farmers can obtain higher cane yield by providing adequate irrigation depending on the need during different crop growth stages and application of chemical fertilizers based on soil analysis. These practices can be better managed under small farms where farmers have greater control. The quality of sugarcane can be improved by harvesting at optimum maturity period and minimizing delivery time of the harvested product from farm to sugar mill.