Bitter Pip in Apples

Horowhenua Chronicle, 26 May 1915, Page 3

Bitter Pip in Apples

Beloro tthe Victorian fruit Commission at present sitting 111 Melbourne interesting evidence was tendered uy Daniel M'Alpine, who described himself at "Bitter Pit Investigator oi tiie Commonwealth and Statu government. ' Bitter pit is one ol tho most destructive of apples diseases. The witness stated that if a tree u ere properly shaped, properly pinned, and uniformly nourished (with the lruit well distributed over the tree) the risk ol bitter pit would be minimised It was known that apples, although free to the eye of bitter pit picked, developed tho disease later. The breathing of animals was of course a ,well-known action, and the apples, too, took hi oxygen, and exuded carbonic acid gas. The freezing point of tho applo was 28 dog. Wifck the applo kept at that temperature there was a "suspension of animation," anil consequently less risk ot mlection. Bitter pit developed under the skin, and consequently in the course of his investigation ho had to "see into the apple." Ho used X rays for that purpose. He took six apples in what might be termed the inciipent stage, and only one apple showed a flaw on tho skin. After the experimental time was over, the apple with tiie flawwas tho only one that "pitted." Comparatively very few kinds of apples were free from pit. The precaution 'of pit on tho growing tree could not be absolutely brought about. A light, fastgrowing tree had tho tendency to "pit." No single operation or method of treatment would prevent pit; his investigation so far had proved that, but the application of various measures would bring the disease within managable proportions. Among those measures that minimised pit, he enumerated proper- pruning for heavy pruning encouraged pit—that was his conclusion after tour years' experimenting; even cultivation, for it enabled soil moistures to uniformly "feed" the trees. Good drainage also tended to reduce the pit; tho pi t was the worst on fruit grown on trees on I low-laying ground. As to irrigation, uniform watering was a very valuable means of reducing the pit. It had been said that bitter pit was accociatod with spraying, but in fact bitter pit ivan known in Australia before jjßfiaying was thought of. A case of t sent to him from Western Austfnlia, where oodlin moth did not exist, .was found on examination to contain from 50 to <30 per ccnt. of bitter pit. The pit was due in some instances to the fruit being undersized.