The Programmed Cell Death In Nicotiana Tabacum Style's Transmitting Tissue

As a part of the pistil, style is an important structure in the female reproductive organs. Two types of style are generally recognized, represented by either the open style of soybean (Glycine max Linn.), or the closed style of cotton (Gossypium hirsutum Linn.). It connects the stigma to the ovary and is the main place of pollen tube growth. Little is currently attention about the function of style during the pistil-pollen interaction. In the closed style, pollen tube growth in the transmitting tissue. It involves pollen tube movement and has multiple roles in guidance, nutrition, adhesion. Some studies have proved the transmitting tissue cells undergo programmed cell death (PCD). Due to the little attention, the type of PCD and the relationship between the transmitting tissue PCD and pollen tube growth are unclear.In order to study the type of PCD in the pollinated and non-pollinated tobacoo's(Nicotiana tabacum Linn.) style, the characteristics in the process of PCD, the differences between the pollinated and non-pollinated transmitting tissue's PCD, using semi-thin sections, histological staining, TUNEL assay and ultrastrctura sections techniques observe the pollinated and non-pollinated tobacoo's styles during the flowering phase. Also, we analyze the relationship between the transmitting tissue PCD and pollen tube growth, and provide the basis for the transmitting tissue's function in pollen tube growth.The main results are as follows. (1) In the non-pollinated style, the pattern of the transmitting tissue cells death is development PCD, although the cell wall doesn't degradation. The transmitting tissue's PCD is senescence. At the end of the blooming, the style abscission along with the flower. (2) There two types of PCD in the transmitting tissue cell death. One type is similar to the non-pollinated style transmitting tissue, another one is a rapidly PCD. In the two types, the cell wall degenerates at the end of PCD. This feature is also different with non-pollination style transmitting tissue. (3) The dramatic changes in the transmitting tissue take place after the pollen tube growth. These changes maybe induce by the pollen tubes, but the regulatory mechanisms need to be further research.