Identification of rice leaf blast disease symptoms: generally occurs after the tillering period. Due to different varieties and meteorological conditions, leaf mites have four symptoms, except for brown spot type (produced on resistant varieties) and white spot type (produced on young leaves of susceptible varieties) In addition, there are acute lesions and chronic lesions that are common in the field.
Acute lesions: When the meteorological conditions are favorable, the lesions are brownish green, nearly round, elliptical or irregular, and the back of the lesions are densely greenish.
Chronic lesions: When the meteorological conditions change greatly, or are transformed by acute lesions, the lesions are mostly fusiform, spindle-shaped, generally brown, with a grayish center in the center, and a yellow or yellowish halo on the outermost layer. There is a brown necrotic line at each end. When the climate is humid, the gray-green mold layer is also produced on the back of the lesion. In the later stage, multiple lesions merge to form irregular large spots, so that the whole leaves die.
Identification of rice cannabis leaf disease symptoms: rice can occur in all growth stages, rice plants occur in the upper part of the plant, but the leaf disease is the main, followed by the panicle. Leaf part: initially a small brown spot, which is expanded into a brown to dark brown oval lesion. It is like sesame grain. The middle part of the lesion is yellow or grayish white, the edge is brown, the outer yellow halo, the ends are blunt round, but there is no necrotic line extending along the leaf edge. According to this, it can be distinguished from rice blast. When the rice plant is deficient in potassium, the lesion is large, slightly fusiform, and the wheel marks on the lesion are obvious.
Symptom recognition of bacterial brown spot disease in rice: also known as bacterial sheath rot, which damages leaves, sheaths, stems, nodes, ears, branches and grains. The leaves are infected, initially brown-water-immersed small spots, and then expanded into a spine-shaped or irregular reddish-brown spots, yellow halos appear at the edges, and the center of the lesions is gray-brown. The lesions often fuse into large spots, causing local necrosis of the leaves. No bacterial pus. The damage of leaf sheaths occurred on the ear mites before the young ears were extracted. The lesions were russet, short strips, and then merged into water-stained irregular large spots, and the central taupe and tissue necrosis. The leaf sheath is peeled off, and there are dark brown streaks on the stem. When the flag leaf is severely affected, the ear can not be extracted. The cob, the hull and the like are damaged to produce a near-round brown spot. In severe cases, the entire hull becomes brown and penetrates into the rice grain.
Rice blight symptom recognition: also known as rust disease, commonly known as dead seedlings, is a physiological disease. Generally, rice begins to occur after tillering. The damaged rice is dwarfed, the old leaves are yellow, the heart leaves are narrow and straight, the stems are small, and the tillers are small and small. In the early stage, the upper leaves are dark green or dark green. In turn, the edges of the old leaves have unclear brown dots or short streaks at the tips of the leaves, and then develop into irregular rust-like spots of varying sizes. Later, the lesions gradually increased and expanded, and the leaves gradually changed from the tip of the leaf to the base to a reddish brown, and spread from the lower leaves to the upper leaves. Only a few leaves remained serious in the whole plant, and the leaves looked like fire. The leaf sheath is similar to the leaf symptoms, producing small reddish-brown spots that later die. There are three reasons for the occurrence of red blight: potassium deficiency, zinc deficiency and root hypoxia.
Product categories of Double Layer Roll Forming Machine,we are specialized
manufacturers from China, Double Layer Roll Forming Machine,sheet rollforming machine,
suppliers/factory,wholesele high-quality product of Double Layer Roll Forming Machine,
R & D and manufacturing , we have perfect after-sales service and technical support . Look forward
to your cooperation !
Double Layer Roll Forming Machine
Double Layer Roll Forming Machine,Double Layer Roll Forming Equipment,Double Layer Roll Making Machine,Double Layer Roll Forming Machinery
BOTOU HUATONG CORRUGATED MACHINERY MANUFACTURING CO.,LTD , http://www.htrollforming.com