The Jonathan fruit spot

Front Cover
University of Wisconsin--Madison, 1915 - 116 pages
 

What people are saying - Write a review

We haven't found any reviews in the usual places.

Common terms and phrases

Popular passages

Page 5 - ... harvest time or in storage). When it first appears one notices spots of deeper red on the darker colored portions and darker green on the lighter portions of the surfaces of affected apples. At this stage they are but slightly sunken, if at all, and there is no suggestion of a bruise. From Brooks' studies it appears that the fungous spots on red surfaces become more sunken later in the season, the color gradually changes from brown to black, and in cellar storage the red spots become badly browned...
Page 3 - In the early stages of fruit-pit one finds numerous sunken areas from two to six millimeters in diameter on the surface of the apple. These depressions are somewhat hemispherical in shape and have the appearance of bruises. At this stage the spots are not brown and often show no difference in color from the surrounding surface of the apple. They may be a deeper red than the adjacent tissue when occurring on the colored portion of the apple and a darker green when on the lighter parts. Later they...
Page 3 - Later the surface cells also become dark brown. The epidermis may be smooth and apparently unbroken in both early and late stages. As the disease advances spots situated near each other often become confluent, developing into one large spot. In all such cases examined it was found that the original spots were closely connected with one vascular branch. The writer has been unable to detect a bitter taste in the browned tissue of the fruit pits. "Internal browning of tissue. The surface spotting is...
Page 3 - ... depressions are somewhat hemispherical in shape and have the appearance of bruises. At this stage the spots are not brown and often show no difference in color from the surrounding surface of the apple. They may be a deeper red than the adjacent tissue when occurring on the colored portion of the apple and a darker green when on the lighter parts. Later they begin to take on a brown tint, but at first this seems to show through from rather deeply seated tissue and not to arise from any discoloration...
Page 9 - Nearly 400 cultures of the disease spots have been made in various ways and on various media, but no organism has been isolated with any degree of consistency. A species of Alternaria often occurred in cultures from fruit grown in the eastern part of the country, but cultures from northwestern-grown fruit were almost entirely barren.
Page 17 - ... to sugar. Cold storage retarded this and other chemical changes but could not prevent them. Otto (22) reported that when ripe apples were allowed to sweat in piles the starch was entirely converted into sugar in two or three weeks, the fruit thus becoming more valuable for cider-making. Zschokke (6) reported that the tannin content decreased in the ripening process. He found that the tannin was located largely in the surface cells of the apple. He believed that apples owed their resistance to...
Page 3 - Sections of such spots show that this is the case, and that the browning and the shrinking of the cells occur in the pulp of the fruit and in the tissue that is transitional between it and the hypodermal parenchyma. Later the surface cells also become dark brown. The epidermis may be smooth and apparently unbroken in both early and late stages. As the disease advances spots situated near each other often become confluent, developing into one large spot. In all such cases examined it was found that...
Page 5 - Baldwin spot docs not appear till nearly harvest time or in storage). When it first appears one notices spots of deeper red on the darker colored portions and darker green on the lighter portions of the surfaces of affected apples. At this stage they are but slightly sunken, if at all, and there is no suggestion of a bruise. From Brooks...
Page 5 - ... cases there is no marked change in their surface appearance. However, according to the experience of the writers, the spots caused by the fungus are not as a rule so large and do not produce such deep pits in the surface as are characteristic of later stages of the non-parasitic trouble. Also on the lighter skinned apples there is not so much danger of confusing the two troubles when one once has the characters of each clearly in mind. On yellow-skinned apples like the Bellflower the spots are...
Page 17 - ... acid, as estimated on a total solids basis, was constantly decreasing. These changes in the sugar and acid content took place very rapidly in the latter half of June and early part of July. The starch content reached its maximum before the last of July and rapidly decreased after that time. Morse (21) found that the most important change in the apple in the " after-ripening " process was the change of starch to sugar. Cold storage retarded this and other chemical changes but could not prevent...

Bibliographic information