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本研究讨论了苹果胚从受精卵到过渡期结束的早期发育。以普通方法阐述早期胚的个体发育，将其作为细胞分裂的精确序列，从正确确定胚的专性部分，这种方法用在苹果上是不可靠的，有人建议用分生组织活性宽广类型来划分个体发育时期。必要时可在形态细小变化的基础上，再分成几个阶段。建议用下列时期：细线期、球状期和过渡期。在细线期胚生长和分裂象一个线状体。在其第一个阶段，受精卵被三层横分裂变成四个细胞的胚，这个胚在体积上不增长；第二个阶段线状胚在体积上直线增加；细胞分裂有横向的及纵向的，并且细胞的容积减小。这时期结束（约受精后１２天）时，胚约有１１－１２层高，长约１２０μ。球状期随着胚生长（即立体平均生长），加大远轴细胞层的体积而开始。细胞分裂有平周和垂周的，而后来在外面的几层细胞平周分裂减少。球状胚直径可达１００μ左右。过渡期以生长分配的变化为标志。在横切面上，胚的上面部分变成椭圆形，而下切面保持圆形。有一些细胞会改变染色能力。这样的细胞最初出现于外底分生组织，接着内底分生组织的细胞也立刻跟上。作者认为，其细胞保持相对稳定，而且深染色的这些组织，在其发生显著变化之前，应该看作残留分生组织。过渡期在子叶原基伸出胚的表面时结束（约?
This study discussed the early development of apple embryos from fertilized eggs to the end of the transitional period. It is not reliable to use this method on apples in order to explain the individual development of early embryos in an ordinary way as an exact sequence of cell division and to correctly identify the obligate part of the embryo. It has been proposed to use a wide variety of meristematic activities Divide the period of individual development. When necessary, small changes in the form based on the sub-divided into several stages. Recommended for the following periods: thin line, spherical and transitional period. In thin-walled embryos grow and divide like a linear body. In its first stage, fertilized eggs are transformed into four-cell embryos by three transverse divisions, which do not increase in size; in the second phase, the linear embryos increase linearly in volume; and the cells divide both horizontally and longitudinally , And the volume of the cells decreases. At the end of this period (about 12 days after fertilization), the embryo is about 11-12 layers tall and about 120 μ long. The globular phase begins with embryo growth (ie, three-dimensional average growth) and increases the volume of the far-axial cell layer. Cell division was flat and vertical weeks, and later on the outer layers of cells reduced perinuclear division. Globular embryo diameter up to about 100μ. The transitional period is marked by changes in growth distribution. On the cross-section, the upper part of the embryo becomes oval while the lower cross-section remains circular. Some cells change the ability to stain. Such cells first appeared in the outgrowth meristem, followed by the cells in the mesogenesis. The authors believe that these cells, whose cells remain relatively stable, and that are heavily stained, should be considered as residual meristem before they have undergone significant changes. The transition period ends when the cotyledon primordium reaches the embryo’s surface (about?