CHANGES ACCOMPANYING FRUIT DEVELOPMENT IN THE GARDEN PEA

Chemical studies on the garden pea were begun at the California Agricultural Experiment Station in 1924. The object of the work was to determine some of the changes that occur in the fruit during development and after harvest. This paper deals specifically with the changes in amounts of some of the components of the pods and peas during their development. The results on storage will be presented in another paper. The investigations were confined mainly to the carbohydrates as it was believed that these played a more important part than other components in the determination of quality. Experimental procedure The variety used was Dwarf Telephone. This is a large-podded wrinkled pea and is the variety used for the spring crop in the Imperial Valley. The seed was planted at the University Farm, Davis, California, on November 20, 1924. The plants were in full bloom on April 9, 1925, and on this date a large number of open flowers were labeled by tying strings around the peduncles. This was done to have fruit of the same age for study. The first picking was made on April 21 when the fruit was 12 days old. The peas at this time were still very small and it was necessary to harvest a large number of fruit to get enough peas for the analyses. A second picking was made on April 27. From this date harvesting was done at two-day intervals until May 15 and then at four-day intervals until May 27. The samples were collected each morning between 7 :30 and 8 :00. Several representative fruits were selected at each harvest and one specimen of each picking is shown in figure 1. A number of fruits were also counted from each day's picking to be used for samples for analysis. These were then immediately shelled and the peas and pods weighed separately. From these data the average fresh weight of the fruit, pods, and peas were calculated and are given in columns 4, 5, and 7 of table I. When weighings were completed the peas and pods were preserved immediately by placing them