Abstract:

In order to optimize irrigation parameters for high-yield or high-quality cucumber production in protected facilities under different soil textures，the effects of irrigation lower limits on growth，yield，and quality of early-spring cucumber were investigated. Cucumber‘Zhongnong 26’was used as experimental material. Three typical soil textures（loam，clay loam，and sandy loam）in major vegetable producing areas were adopted. Three irrigation lower limits for each soil texture were performed from fruiting period，including 60%，70%，and 80% of filed capacity. When soil water content dropped to irrigation lower limit，corresponding irrigation system initiated. The irrigation amount was the calculated variation of soil water content from irrigation lower limit to 90% of field capacity. Results showed that for loam，clay loam，and sandy loam，70%，60%，and 80% of field capacity were the optimal irrigation limits for high-yield cucumber cultivation，which could reach up to 110 800，130 300，and 125 000 kg · hm^-2，respectively，together with high irrigation water use efficiency，which could reach up to 45.1，42.3，and 45.3 kg · m^-3，respectively. For loam，clay loam，and sandy loam，60%，80%，and 60% of field capacity were the recommended irrigation limits to obtain high contents of soluble sugar and vitamin C，respectively.

Key words: cucumber, greenhouse, irrigation, soil texture, high yield, high quality