24 UNIV. OF N. H. AGR. EXPERIMENT STATION [Bulletin 238 



There was little difference in the total yield. _ The hest yield was obtained 

 from plants that received the extra heavy application of manure; here the 

 increase was 10 to 15 percent, which may have been due to increased size 

 of fruit. (Hatch Fund.) 



APPLE POLLINATION 



In spite of cold weather before and persistent rain during the blossom 

 period, further data on pollination were obtained in 1928 by L. P. Latimer. 

 This season, as last, tests in which the petals were removed from the 

 flowers proved Mcintosh self -sterile under the prevailing climatic condi- 

 tions. The removal of the petals prevents the bees and other insects, which 

 are responsible for cross-pollination, from visiting the blooms, and renders 



it necessary for them to be fertilized by their own pollen only. The de- 

 petaled spurs ai"e not bagged, nor is the tree placed under a cage. They are 

 compared with alternate spurs on the same branches to which insects bring 

 various kinds of foreign pollen. The depetaled Mcintosh spurs set no 

 fruit, while the cross-pollinated spurs that alternated with them on the same 

 branches set IG percent. By this same method Gravenstein was found to 

 be self -sterile, but Wealthy produced a high percentage of fruit on flowers 

 without petals, and accordingly must be self-fertile. 



Good sets of fruit on Gravenstein were obtained with Wagener pollen on 

 flowers that were both emasculated and bagged. Red Astrachan and 

 Oldenburg pollens produced fruit on flowers which were bagged but not 

 emasculated, but Baldwin, Mcintosh, Delicious, and Gravenstein pollen 

 produced no set under any conditions. The wound inflicted in emasculat- 

 ing apparently reduced the chance of the flower to set fruit. (Hatch 

 Fund.) 



BREEDING TOMATO PLANTS 



Records of growth and production from first generation hybrids of sev- 

 eral varieties of tomatoes have been summarized by J. R. Hepler. Ap- 

 proximately 72 plants each of Bonny Best, Dwarf Champion, Ponderosa, 

 Earliana, Sunrise and 20 different first generation hybrids of these varieties 

 were planted in eight replicate plots. Records were made of the number 

 and weight of fruits on each plant, and for 21 plants of each strain, records 

 were also made of the amount of growth produced and blossom clusters 

 formed. 



The results indicate that the crosses are more vigorous than the parents. 

 The increased growth of the hybrid as compared to the average for the two 

 parents varied from 12^ to 136 percent. The average growth for all 20 

 of the first generation hybrids was about 62 percent greater than the aver- 

 age for the five parent varieties. 



In yield the crosses outstripped their parents by from 12 to 89 percent, 

 averaging 42 percent higher. The increased yield was due to a larger 

 number of fruits which, on the average, were somewhat smaller than those 

 borne by the parents. The size of fruit on the crosses seems to be similar 

 to the size of fruit on the smaller-fruited of the two parents. This was 

 especially true in crosses of the Sunrise variety, in which the fruits on the 

 average weighed less than three ounces each. (Hatch Fund.) 



