Losses to cotton, what to look for and where to find it, being one of a series of articles in relation to crops, their common diseases and insect pests to which they are subject . r more of tlie nuiin 26 ribs of the leaf, being bounded on either side by an ir-regular zigzag line. In time the spots become blackish andthen brown, and are frequently bordered by a blackish colorwhere the disease has spread outward from a centrallyinfected spot. The dead s])ots in the leaf sometimes break out, leav-ing many perforations with ragged edges, somewhat asoften results in cotton leaf blight; the disease
Losses to cotton, what to look for and where to find it, being one of a series of articles in relation to crops, their common diseases and insect pests to which they are subject . r more of tlie nuiin 26 ribs of the leaf, being bounded on either side by an ir-regular zigzag line. In time the spots become blackish andthen brown, and are frequently bordered by a blackish colorwhere the disease has spread outward from a centrallyinfected spot. The dead s])ots in the leaf sometimes break out, leav-ing many perforations with ragged edges, somewhat asoften results in cotton leaf blight; the disease hastens thefalling of the leaves. In the very earliest appearance of the spots, when thewatery condition is coming on, these spots swarm with bac-teria; these also often occur on the plant bolls which pre-sent spots of watery a])])earance, and these finally terminatein rot and death. In this case the general weakness of thel)lant naturally extends to the boll also. Mosaic, Yellow Leaf Blight, or Black Rust The first signs of mosaic are yellowish spots which givethe leaf a checkered ai)pearance. These discolorations oc-cur first in small areas, which are roughly rectangular. MOSAIC DISEASE, OR YELLOW LEAF BLIGHT27 owing to the limitation cansed by the veins and are situatedat points most remote from the main feeding veins. In later stages these weakened areas may be over-grown by various fungi. Usually the centers of these spotssoon turn brown, and the brown parts enlarge and show aseries of concentric markings. If very dark-colored fungigrow upon these spots, they soon become black-coated, andfrom this fact take the popular name black rust, which,however, bears no similarity to, or relation with, the rustof the cereals. The attack of the fungus causes the pre-mature falling of the leaf, thus preventing the proper ma-turity of the i^lant. Losses may vary from 5 to 50 per cent,and, being widely distributed, such losses are often veryheavy. It may be safely asserted that this dise
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