玉米应力裂纹的显微分析

Microscopic Structure Analysis on Stress Cracks in Corn

观察了３种应力裂纹类型（单裂、双裂、龟裂）玉米的内部显微结构和应力裂纹产生的位置、数量、宽度，分析了应力裂纹在胚乳中扩展的情况以及应力裂纹对胚乳结构产生的影响。裂纹的类型不同，裂纹的形态、数量及大小亦不同。应力裂纹生成在粉质胚乳的中心部位，沿淀粉颗粒的边缘向外扩展。应力裂纹是内部裂纹，只能扩展到种皮附近，接近糊粉层。

Microscopic structure of three kinds of stress cracks(single,double ,multiple) in corn was observed.The location,size,number and extension of stress cracks in endosperm were analyzed.For different grain kernels,the form,number and size of stress cracks are different.Stress cracks originate at the inner corn of the floury endosperm and propagate radically outward along the boundary of starch granules, they cannot advance enough to rip the pericarp,and only reach to the area closing to aleurone layer.