【摘要】 利用扫描电镜观察品质差异较大的 4个籼稻品种稻米糊化前后的微结构 ,发现同等条件下不同部位的糊化明显不同。背部糊化最好 ,细胞完全崩解为絮状或小块状的蓬松物质 ;腹部糊化次之 ,呈较大块状或细胞结构刚被破坏 ,有的细胞轮廓仍可见 ;中部糊化最差 ,多为完整胚乳细胞。不同品种糊化后差异明显 ,米质好的品种其背、中、腹部的糊化比米质差的品种的相应部位好 ,米质较差品种的中部明显凹陷 ,而较优品种的断面较平 ,该现象同样表现在早、晚稻的对比上。品种间背部糊化的差异小于中、腹部 ,品种内米质较优的稻米背、腹、中部的差异比米质差的小。米质较好的品种的胚乳横断面可见较多断裂的细胞 ,而米质较差的品种几乎见不到断裂的细胞 ,其数目与米质优劣有一定的正相关。米质优劣与糊化时的吸水率和延长率正相关 ,吸水率和延长率高则糊化较好更多还原

【Abstract】 The microscopic structures of the endosperm of indica rice varieties with different qualities before and after gelinization was observed by scanning electron microscopy. The results show that the degree of gelatinization varies from diversified places and varieties at the same condition. The gelatinization of dorsal side is the best; its cells are destroyed totally, leaving the puff, flocculent material. The ventral side that gelatinizes better appears agglomerate and the cell shape is indistinct. The middle place, which gelatinizes badly, maintains integrate cells. Evident differences exist among different varieties after galinization. The gelatinization degree of dorsal, ventral and middle part of high quality variety was better than the homologous place of low quality variety. In low quality variety, obvious concave locates in the middle part while the transection of nice varieties is quite flat. The contrast between early indica rice and late indica rice shows the same phenomenon. Difference of dorsal sides is less than middle area and ventral sides among varieties after gelatinization. The inferior rice possesses great difference among dorsal side, middle area and ventral side than superior one. Furthermore little rupture cell can be seen in the transection of low quality rice while lots of rupture cells can be observed in the high quality rice. Evidently the number of rupture cell has a positive correlation with rice quality to a certainty. Quality of rice has a positive correlation with rate of absorbing water and rate of extension. High rate of absorbing water and rate of extension cause better gelinization of rice, and indicates the good quality.更多还原