关键词: 小麦, 戊聚糖, 播期, 水分胁迫, 库源, 氮素

Abstract:

Pentosan plays important role in determining quality for baking, forage, beer-making and health food in wheat. However, knowledge of cultivation practices impacts on pentosan content in wheat grain were investigated based on a serial of field and pool experiment. Cultivars of Xuzhou 26, Yangmai 10, Yangmai 9 and Ningmai 9 were selected with five treatments including sowing date, spikelet and leaf removal, interaction of water stresses and nitrogen, nitrogen rate and nitrogen topdressing were conducted in 2001–2004. The results indicated that early and late sowing treatments significantly increased pentosan content in wheat grains by 2.13% and 8.07% respectively compared with that of period sowing date treatment (Fig.1). As compared with the control, pentosan content with spikelet-removal (sink reduction) treatment was decreased by 9.38% and 6.97% while that in flag leaf-removal (source reduction) treatment was increased by 1.81% and 14.83% in Xuzhou 26 and Yangmai 9, respectively (Fig.2). The main effects of water stress and nitrogen and the interaction effect between water and nitrogen were significant on grain pentosan content. Grain pentosan content in wheat under post anthesis waterloging was 2.87% lower than that of control. Impacts of nitrogen and water interaction on pentosan content differed with cultivars (Table 2). Grain pentosan content decreased with increasing nitrogen, however the decreasing tendency slowed down with increasing nitrogen. Pentosan content in wheat grains was significantly decreased by topdressing nitrogen (Fig.3–4). Pentosan content showed linearly correlated to grain weight when single grain weight exceeds 40 mg. In conclusion, these cultivation practices significantly regulated thousand-grain weight and subsequently determined grain pentosan content in wheat.

Key words: Wheat, Pentosan, Sowing date, Water stress, Source and sink, Nitrogen