1. Potassium deficiency is evident in the plant. During the seedling stage, the leaves appear bluish-green, while older leaves remain soft and covered. The heart leaves grow straight, and the tips of middle to lower leaves show red-brown necrotic tissue with irregular red-brown spots. As the condition progresses, the plant exhibits premature aging, leaf scorching, scattered rice pods, and stunted growth. Roots become more brown, weak, and show signs of early aging. The grains lack luster, are not fully developed, and the plants are prone to lodging and infection by diseases such as flax or spot disease.
2. Rice leaf spot disease, also known as rice leaf blight, is a widespread issue across all rice-growing regions. It can affect plants from the seedling stage right up to harvest. Infected plants suffer damage above ground, particularly in the leaves. In the early bud stage, the coleoptile turns brown, preventing proper emergence, and the cotyledons wither. Seedlings often show elliptical lesions on the leaves and sheaths, resembling flax seeds in size, dark brown in color, and sometimes expanding into long stripes that lead to leaf death. In adult plants, the initial symptoms are small brown spots on the leaves, which gradually grow into oval-shaped lesions, similar to sesame seeds. These spots have a brown to gray center, dark borders, and yellow halos around them. As the disease progresses, the leaves dry inward from the tip, turning light brown, and black mold (conidiophores and conidia) appears on the dead tissue. Lesions on the leaf sheaths are oval, dark brown, with brown edges and water-soaked areas that later develop into irregular large spots with a taupe center. Infected panicles show dark brown discoloration, leading to dry ears. Grain infection starts with grayish-black spots, which expand over time, causing the grain to shrivel. In later stages, the lesions are small, with unclear edges, and the infected grains become brittle. Under humid conditions, a black fungal layer forms on the infected parts, consisting of the pathogen's conidiophores and spores.
Arm Portable CMM
Arm Portable CMM
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