THE HORTICULTURAL SOCIETY OF NEW YORK 



unproductiveness are wrongly attributed to self -incompatibility 

 and also that cross-pollination may have occurred where it was not 

 expected. It is not at all certain that the differences in fruit pro- 

 duction observed in these cases were due to variations in the one 

 factor of self-fertilization. But unless experience shows that a 

 clonal variety of these much cultivated fruits is decidedly fruitful, 

 the safe course for the grower is to interplant rather liberally. 



Perhaps an important advance in horticulture will be the com- 

 bining of a high degree of self -compatibility with high quality of 

 fruit and other desirable qualities through further breeding of 

 all of the various fruit crops in which incompatibilities are now 

 marked. This would allow solid block plantings with the advan- 

 tages in orchard management that this brings. It would make 

 yields of fruits less dependent upon insect pollination in that the 

 self- and close-pollinations would be sufficient. 



But possibly the ultimate and most ideal goal of the horticultur- 

 ist is to develop fruits like the Navel Orange which mature fruit 

 without any pollination ; the problems of pollination and fertiliza- 

 tion are then entirely eliminated in the matter of securing yields 

 of fruit. 



It is to be emphasized that the abundant yields of fruit by a new 

 seedling or by plants vegetatively propagated from it when grown 

 in trial orchards or in nursery plantings when surrounded by 

 other varieties is no test for sclf-fruitfidness. This simply shows 

 that the plant or the clonal variety is able to produce fruit. 

 Whether the plant is a female intersex, whether there are structural 

 adaptations or dichogamy limiting both self- and close-pollinations 

 or whether there are self-incompatibilities is not in the least re- 

 vealed. There is no evidence from this as to what the pollination 

 or fertilization requirements are or of how the variety will yield 

 when planted alone or in solid blocks. 



The ideal plant for vegetative propagation and for solid block 

 planting from the standpoint of consistent yields of fruit is one 

 that is self -fruitful. For it to be thus, it should have perfect 

 flowers, there should be no structural or developmental adaptations 

 that decidedly limit close-pollination at least and preferably self- 

 pollination also, and the self- and close-pollinations should be 



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