. Breeding crop plants. Plant breeding. FRUIT BREEDING 273 The chief conclusions which may be reached from these results are that nearly all varieties are heterozygous for color and that white is a pure recessive. In studies of inheritance of quality there is a proof of the value of selecting as parents the types which excel for the character being worked with. Table LXXIV gives some of the results of crosses in which quality was studied. Table LXXIV.—Inheritance of Quality in the Grape Parental types Total. Percentage of good or better Parents good or of higher quality. Good X fair or poor Me
. Breeding crop plants. Plant breeding. FRUIT BREEDING 273 The chief conclusions which may be reached from these results are that nearly all varieties are heterozygous for color and that white is a pure recessive. In studies of inheritance of quality there is a proof of the value of selecting as parents the types which excel for the character being worked with. Table LXXIV gives some of the results of crosses in which quality was studied. Table LXXIV.—Inheritance of Quality in the Grape Parental types Total. Percentage of good or better Parents good or of higher quality. Good X fair or poor Medium X medium Poor X poor 27 11 10 4 Nearly all grapes of high quality at the New York station contain some V. vinifera blood. This is easily understood when one remembers the long period of breeding of the European varieties and that American varieties were only recently obtained from the wild. Inheritance of size of grape berry and ripening period showed the value of selecting as parents varieties which excel in the character which the breeder wishes to obtain. Illustrations of Methods of Breeding.—Methods of breeding fall naturally under three main heads; 1. Selection of bud sports. 2. Seedling selection. 3. Controlled crosses. As has been already mentioned many of our varieties have resulted from chance seedlings, others from seedlings in which only one parent was known. A review of the subject leads to the conclusion that the improvement of fruits by the use of self- fertilized seed is a less desirable method than by the use of crossed seed. When selfed seed can be produced the progeny are as a rule less vigorous than those obtained from crossed seed. As these subjects have been touched upon in some detail under other headings, seedling selection will not be discussed further. Selection of Bud Sports.—It is now a commonly accepted fact that mutations or sudden changes in the germinal material do occasionally occur. Likewise, in asexually propagated species 18. Please
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