Abnormality in Sweet Cherry Blossoms and Fruit
Abnormality in Sweet Cherry Blossoms and Fruit
复制标题
甜樱花和果实的异常
作者：
G. Philp
Many abnormal sweet cherry (Prunus avium) flowers were observed during the spring of 1932. In the midseason varieties, Napoleon, Bing, and Hoskins, many flowers showed several pistils extending through the tip of the unopened blossom. Upon examination it was discovered that these protruding pistils instead of anthers occurred at the tips of the filaments (fig. I). Figure 2 shows a normal blossom. In many cases abnormal development of the petals had also occurred (fig. 3). An occasional abnormal blossom had been observed in other years, but in 1932 so many were encountered, particularly in the Napoleon and Bing varieties, at the University Farm, Davis, California, that it was decided to investigate the extent of this abnormality. There are extensive cherry plantings in Santa Clara, Sonoma, Napa, Solano, Sutter, Placer, and San Joaquin counties. Observations were made in all of these areas for abnormal cherry flowers, and at harvest season fruit was examined. It was found that the occurrence of abnormal flowers was extensive in the hot interior valleys of the Sacramento and San Joaquin, becoming considerably less in the Sierra Nevada foothills to the east and also in the foothills to the west. No abnormal flowers were found in the coastal valleys of Santa Clara, Napa, and Sonoma, where summer temperatures are lower. Practically all the abnormal flowers contained double pistils (fig. 4), which upon development produced double or malformed fruits (fig. 5). Fruit counts, however, indicated that many otherwise normal blossoms contained double pistils as illustrated in figure 4. In a cherry orchard in Sutter County, a number of spurs having abnormal blossoms were tagged. All the normal flowers were removed and only flowers showing abnormal pistil or petal development were counted. No record was made as to whether or not the ab-
