The Role of Plant Hormones in Fruit Development

[摘要] Starting with the initiation of the ovary primordium, a coordinatestudy of the hormonal relationships in fruit growth has beenattempted with fruits attached on the plants and also by the new techniqueof in vitro culture. Several phases were recognized in theontogeny of a fruit. To be able to initiate flower primordia the planthas first to enter a reproductive condition. The formation of ovaryprimordia was studied in some cucurbits, in which it was foundthat the environment profoundly influences the apparition of femalevs. male flowers. It has been concluded that these environmentalfactors regulate the length of successive phases in cucurbit flowering. Once initiated, the ovary enlarges regularly, mainly by celldivision until anthesis. If pollination is prevented, ovary growthceases at this stage, and there is indication that the auxin level ofthe flower decreases. The ovary then shrinks or drops off theplant. Flower abscission is prevented and growth is stimulated bythe pollen which performs these effects mainly by increasing theauxin level of the ovary, partly at least through an enzymatic mechanism.After fertilization fruit growth is controlled by the developing seeds which release large quantities of auxin, the latter apparentlymanufactured in the endosperm. Thus, auxin has been found to affect any stage of fruit development.

[发布机构] University:California Institute of Technology;Department:Biology

[关键词] Biology