Effect of scape cut during bulb development stage on carbohydrate formation and yield of garlic (Allium sativum L.).

摘要

This study was conducted to investigate the effect of scape cut during bulb development stage on leaf dryness, carbohydrate and yield of garlic (Allium sativum) in the field. The cloves were planted on polyethylene film-mulching plots at 18x11 cm on 25 September 2006 and harvested on 30 May 2007. Time of scape cut was on 4 May 2007. Percentage of leaf dryness of no scape cut was slowly increased from 24.3% on 14 May to 63.9% on 30 May, while that of scape cut was rapidly increased from 27.1 to 75.5%, respectively. Leaf area of scape cut and no scape cut were 141.2 and 228.1 cm2 per plant on 30 May. The photosynthetic rate was similar to 11.0-10.9 micro mol m-2 s-1 on 14 May but photosynthetic rate of no scape cut increased to 13.4 micro mol m-2 s-1 on 19 May compared to 12.7 micro mol m-2 s-1 for scape cut. The glucose and sucrose content in leaves and leaf sheath of non scape cut were gradually decreased and the fructose was increased during bulb development stage. The fructose content in leaves of scape cut was high as 137.3 mg/g compared to 80.6 mg/g of no scape cut on 30 May. However, the fructose content in leaf sheath of scape cut was greatly decreased and then gradually increased. The sucrose content of scape include bulbil was decreased to 89.1 mg/g on 30 May compared to 145.0 mg/g on 9 May and the fructose was increased during bulb development stage. The sucrose content of bulb in no scape cut was gradually increased. On the other hand, the sucrose content of bulb in scape cut off was greatly increased from 499.2 mg/g on 9 May to 803.2 mg/g on 30 May. The ratio of large bulb diameter (above 45 mm), bulb weight and yield of scape cut were 61.1%, 34.2 g, and 1310 kg/10a, respectively. The yield of no scape cut was decreased to 8.6% compared to 1197 kg/10a for scape cut.