奶桑种子外部形态及其育苗推荐用种量

为在奶桑育苗中准确推荐用种量,形成技术参数标准,以桑栽培品种‘冀桑3号’的种子为对照,研究奶桑资源驯化种‘攀枝花1号’单粒种子的外部形态结构（长度、宽度、最大投影面积、长宽比、面积系数、单粒重、单粒厚度、单粒体积、单粒密度和千粒重）和种子堆体特征（种子容重、种子比重、种子密度和种子孔隙度）,得到奶桑育苗的推荐质量用种量和推荐体积用种量。结果表明：（1）‘攀枝花1号’种皮为亮棕色、具表皮毛,种柄短;‘冀桑3号’种皮为暗棕色、表皮光滑无毛,种柄较长。两者的种子都为五面体,但‘冀桑3号’较‘攀枝花1号’更为扁平,‘攀枝花1号’的立体感更强。（2）‘攀枝花1号’单粒种子的长度、宽度、最大投影面积、长宽比、面积系数、单粒体积和千粒重较‘冀桑3号’小,分别只有‘冀桑3号’的45.21%、69.04%、53.06%、68.71%、93.20%、26.94%和32.86%。（3）‘攀枝花1号’种子堆体的种子容重、种子比重、种子孔隙度分别为‘冀桑3号’的58.88%、51.25%和85.26%。（4）‘攀枝花1号’的种子推荐质量用种量和体积用种量分别为1.35 kg/hm²和5.55 L/hm²。研究结果可为奶桑的育苗以及种子的生产和储存提供科学依据。

The External Morphology of Morus macroura Seeds and the Recommended Amount of Seeds for Seedling

To accurately recommend the amount of mulberry seeds used in nursery, the standard of technical parameters was formed. The single seed morphological structure (such as length, width, maximum projection area, aspect ratio, area coefficient, single grain weight, single grain thickness, single grain volume, single grain density, 1000-grain weight) and the characteristics of seed accumulations (seed bulk density, seed specific gravity, seed density and seed porosity) of ‘Panzhihua 1’ (a resource domesticated species of Morus macroura) were studied by a comparison with seeds of ‘Jisang 3’ (a resource domesticated species of Morus alba). The results show that: (1) the testa of ‘Panzhihua 1’ is bright brown, with surface coat and short stipe; the testa of ‘Jisang 3’ is dark brown, smooth and hairless, with long stipe; although the seeds of both species are pentahedral, ‘Jisang 3’ is more flat, and ‘Panzhihua 1’ is more three-dimensional; (2) the length, width, maximum projection area, length width ratio, area coefficient, single seed volume and 1000 seed weight of ‘Panzhihua 1’ are smaller than those of ‘Jisang 3’, only 45.21%, 69.04%, 53.06%, 68.71%, 93.20%, 26.94% and 32.86% of those of ‘Jisang 3’, respectively; (3) the seed bulk density, seed proportion and seed porosity of ‘Panzhihua 1’ are 58.88%, 51.25% and 85.26% of those of ‘Jisang 3’ respectively; (4) the recommended seed quality and volume of ‘Panzhihua 1’ are 1.35 kg/hm² and 5.55 L/hm², respectively. The results could provide a basis for the seedling, and production and storage of the seeds of Morus macroura.