. Fig. 8.—Speckled leaf blotch of wheat. The presence of the fungus is indi- cated by the many black dots in the blotched regions. over the leaf surface, fig. 8. It is especially abundant on lower leaves. The spots contain many tiny, black specks not nearly as large as pinheads but plainly visible to the unaided eye. This disease exhibits symptoms that vary somewhat with the season. In late fall, it may be recognized as more or less circular to oval, speckled spots on the blades of the seedling leaves. The centers of the spots are at first light green, which shades into the natu- ral green of
. Fig. 8.—Speckled leaf blotch of wheat. The presence of the fungus is indi- cated by the many black dots in the blotched regions. over the leaf surface, fig. 8. It is especially abundant on lower leaves. The spots contain many tiny, black specks not nearly as large as pinheads but plainly visible to the unaided eye. This disease exhibits symptoms that vary somewhat with the season. In late fall, it may be recognized as more or less circular to oval, speckled spots on the blades of the seedling leaves. The centers of the spots are at first light green, which shades into the natu- ral green of the leaf, but the spots are not very conspicuous until the black fruiting bodies of the fungus are formed. In the spring the spots gradually elongate as the fungus grows in the leaf tissue, turn reddish brown and, as a rule, become partially surrounded by a yellowish band. The oldest part of the spot usually turns to light brown or even ashen white and is studded with tiny, black specks. Heavily infected leaves often have a yellowish cast and may die prematurely. Very little new infec- tion occurs after flowering. Life History.—After the wheat crop is mature and har- vested, the speckled leaf blotch fungus lives through the summer
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Keywords: ., bookcentury1900, bookcolle, bookpublisherurbana, booksubjectgrain
