The rubber tree book . nt of the plant—unite in thecentre, forming one column. In the female flower each ovuleis divided into thin-walled cells, and surrounded by them is theovum, the female element. Fertilization in the case of the Hevea is by means of wind-borne pollen, that is to say, by a form of cross-fertilization. Fewof the higher members of the vegetable kingdom are self-fertilized. It is a general law of Nature that vigorous growthand healthy life can only be secured when cross-fertilizationhas taken place. All planters know how, when th§ Heveasare in flower, the whole air is full of
The rubber tree book . nt of the plant—unite in thecentre, forming one column. In the female flower each ovuleis divided into thin-walled cells, and surrounded by them is theovum, the female element. Fertilization in the case of the Hevea is by means of wind-borne pollen, that is to say, by a form of cross-fertilization. Fewof the higher members of the vegetable kingdom are self-fertilized. It is a general law of Nature that vigorous growthand healthy life can only be secured when cross-fertilizationhas taken place. All planters know how, when th§ Heveasare in flower, the whole air is full of the scent from the pollenwhich fills the air in the neighbourhood of the trees. In thisway cross-fertilization is secured, the pollen from one tree beingwafted to others. When the ovule has undergone certain changes as the resultof fertilization, it becomes a seed, and, granted favourable con-ditions, will germinate and produce a plant. The young plantwill not be produced from the whole seed, but only from a part 26. Fig. 6.—Seed and Seedling Plant. THE SEED AND ITS FERTILIZATION 29 of it. That part is called the embryo. When germinationtakes place the embryo pushes its way out of the seed; theyoung rootlet, called at this stage the radicle, turning down,and the young stem pushing its way upwards towards light andair. Just as the embryo of a chicken has a store of food uponwhich to feed and develop before it leaves the egg-shell, so theembryo of the young Hevea plant has a sufficient store of foodinside the seed to supply its needs until the rootlet has attaineda proper hold of the soil. On the young stem which pushesits way upward through the soil to light and air are two smallleaves, formed in the seed and helping the young plantthrough its early stages, which later on shrivel up and die. Itwill be seen, therefore, that just as the acorn holds in miniaturethe future oak tree, so in the seed of the Hevea are to be foundin the embryo the root, the stem, and the first leave
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Keywords: ., bookcentury1900, bookdecade1910, bookidrubbertreebo, bookyear1913
