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Show AGRONOMY Edited by Prof. J. S. Hogenson, A. C. U. . HYBRIDS AND CROSSES. Abstracted From Article by Swingle and Webber. No question is of more interest to farmers and gardeners than the improvement im-provement of cultivated plants. The great variety of soil and climatic cli-matic conditions in this country renders rend-ers it necessary to have many sortss of 'plants differing in their rpquirc-ments. rpquirc-ments. A grain grown here may be almost totally unfit for general agriculture agri-culture in Florida, the same is true of various other parts of the country. Again the maximum productiveness of most of our cultivated plants has not been reached, so that much is still to be gained in this direction. What can be accomplished by close application to crossing 'and hybridizing hybrid-izing is shown by the wonderful results re-sults obtained by Burbank and Mun- Vll. A' hybrid is the offspring obtained by the uniting of two plants of different dif-ferent species while a cross is the offspring of two varieties of one species. spe-cies. The process of hybridizing plant, is in itself neither difficult nor mysterious, mys-terious, it being simply necessary to understand the general ' structure of the flower to be used. The flowers of the pear tomato arc common forms of perfect flowers. The envelopes en-velopes of these flowers consist of two whorls of modified leaves. The outer whorl, which is known as the calyx, is commonly green in color. The inner whorl, which is known as the corolla is usnalllyof some (bright color other than green. The 'essential 'essen-tial or sexual organs of the flowcrr the sjaniens and pistils -arc found inside the two whorls of leaves and it is with these organs that the plant-' breeder is most concerned. 'The stamens or male organs arc usually several in number, and are composed of an upper swollen portion which is born on a rather slcntlcr stalk. The upper swollen portion which contains, con-tains, when mature, small sacks of yellowish powdery grains called pollen, pol-len, which is the male fecundating clement. A quantity of this pollen must be transferred to the stigma ol the female organ before fecundation can lake place. ' The pistil wliich is the female organ, or-gan, occupies the center of .the flower and is 'surrounded by the stamens. The upper portion of the pistil is swollen and somewhat . rough or sticky. It is cm this portion of the pistil, known as the stigma, that the pollen must fnll'to produce fecundation. fecunda-tion. In the majority of plants both the male and female .organs arc produced in the same flower, in others they arc produced in different flowers on i the same plant, or on different plants ( entirely . i The most important 'feature in j crossing and hybridizing is to exclude ex-clude from; the stigma all pollen ex- ' ccpt that which is desired to use. Where all the essential 'organs oc-:ur oc-:ur in the same flowcr therefore, the fl6wcr intended for hybridization must be carefully opened while still immature and the stamens pulled1 off. Pollen is then taken from the desired de-sired flower and placed on the stigma stig-ma of the flower where the stamens were removed. After this is done a cloth or paper bag is tied over the flower to keep out all insects and pollen carried by the wind. Very many of our best plants have been produced by careful hybridization. hybridiza-tion. Judging fronu the results obtained, ob-tained, it would seem that almost any dfcsircd variation can ibe produc-cd produc-cd if a sufficient amount of time, patience, and skill is brought to bear on its production. It -is by means of hybridization or crossing that the desired qualities pf two individuals may be brought into oitc. plant. Some of the important results secured se-cured arc: ist, increased size and vigor. vig-or. 2nd, breeding for hardiness. 3rd. adaptation to climate. 4th, sorts resistant re-sistant to diseases. 5th, increased per ccntagc of the desired plant foods such as starch, sugar etc. 6th, change of season and of the length of duration of life. 7th, increase in yield. 8th, acquisition of odor. 9th, better quality and flavqr, modification modifica-tion of color, etc. Hybridization followed by selection lias brought and may yet bring into existence some of the most useful varieties and sorts of plants viewed from the standpoint of utility to man. ' There arc two things upon which no man and woman ever agreed: The I good sense in riding a lodge goat or reading a paper at a Mother's club. j Atchison Globe. Mr. Rockefeller believes in a dis-tributon dis-tributon of wealth, probably because it is easier to get a little away from each one of several million people than it is to get a big wad away from one individual. The Commoner. A man regards his newspaper in the way he docs his wife: something to find fault with when he is cross, and something he never entirely approves ap-proves of. Atchison Globe. |