Study On The Structural Characteristics Of Bisexual Flower In Main Vine Of Muskmelon (Cucumis Melo L. Var. Reticulatus Naud.) Induced By Ethephon

Muskmelon(Cucumis melo L.var.Reticulatus Naud.) is commonly known as "Cantaloupe",which is kind of Cucurbitaceae Cucumis melons as a one-year-old sprawl plant.It is common of andromonoecy in muskmelon.Its male flower mainly grows on main vine and bisexual flower on lateral vine.The air humidity is big and the temperature is high in the fruit mature period of spring culture stage around the Yangtze valley;while the light is weak and the temperature is low in later growth period of autumn cultivation.In these two later periods of cultivation seasons,the environmental condition all does not favor the fruit to be mature.Treating muskmelon with ethylene in the seedling stage can induce its main vine to form bisexual flowers,and make its pollination date and the fruit mature period ahead of time,so as to avoid the failure in cultivation because of the bad environment in later growing period.At the same time,it has important application value in the production,which not only promote the fruit ahead of time recovery but also raise economic and the social efficiency.During this study,the Muskmelon(Cucumis melo L.var.reticulatus Naud.) seedlings were treated with Ethephon in order to induce the formation of bisexual flowers in main vine.Our aim is to observe differentiation processes of flower buds and study on the process and the characteristic of the formation of the bisexual flowers in main vine.We observe and compare the similarities and differences of anatomical structure and ultrastructure of pollen in different sexual types,and also measure the vigor of pollen in the flowers.The findings are as follows:1 Ethophon treating can induce the formation of bisexual flowers in main vine,which grow normally.The differentiation process of flower primordium in main vine of untreated plant in early stage is the same with bisexual flower.But after the appearance of pistill primordium,it dosen't develop continually,then form male flower at last.They all have a common process that from sepal to petal,then stamen and pistill at last.The induced bisexual flower in main vine have no differences with the bisexual flowers in lateral vine in anatomy.It shows that the ethophon treating don't change the process of differentiation in flower buds and anatomical characteristics. 2 The anatomical structure is the same among male flowers,they all have 5 anthers, which adhere tightly to each other,splitting into 3 groups.So are the bisexual flowers.The difference between the female and bisexual flower is the extent of adhere in anthers.There are no differences of the ultrastructure of pollens in different sexual types;The vigor of pollen in bisexual flowers of main vine in treated plants is lower than other sexual types'. The pollen in lateral bisexual flowers of control seedlings,bisexual flowers of main vine seedlings and lateral bisexual flowers in treated seedlings can all make bisexual flowers of main vine in treated seedlings fertilization,and tie melons finally.