Scientific name Nymphula fluctuosalis Zeller Lepidoptera, Polygonaceae. The alias is rice straw tuber and rice tuber. Distribution of Fujian, Taiwan, Guangdong, Guangxi, Sichuan, Yunnan, Henan, Ningxia, Guizhou and other provinces.
Host rice, water lily, aquatic weeds and so on.
The larvae live in the water. The rice larvae bite into pieces and spit together into a tube. They hide in the tube and infest rice leaves, causing many leaf tubes to float on the water.
Morphological characteristics Adult body length 6-7mm, wingspan 13-19mm, head, chest, abdomen white, with black spots. The sub-baseline of the forewings and the inner horizontal line are black and sloping, with a brownish yellow color from the middle to the inner edge. The upper corner of the middle chamber has one distinct brown-yellow marking, one black dot, and one dark-yellow-bandwidth that is very oblique. From the leading edge The lower corner bends. The hind wings have a sloping subbaseline from the mid-chamber to the inner rim, and the inner rim intersects with another oblique line that protrudes from the center of the leading edge. The outer transverse line is slightly curved and tilted, brownish-yellow with black edges. The submarine line is black and the edge line is brownish yellow. Egg white, long lemon-shaped, tip-shaped at one end, flat at the end, showing longitudinal grooves. The last instar larvae have a body length of about 13 mm, yellow-white gray, smooth and hairless, with darker ends and a light yellow head. The pronotum is light brown with auburn spots. About 8mm long, pale yellow, 2-4 section of the abdomen air holes prominent, red brown.
Habits of life in the South 2 generations. Larvae live in water, larvae abdomen two
The filamentous elongated tracheal fistula stretches sideways to breathe, and the larvae spine after the old larvae have matured. Adults of Ningxia flourish in the middle and late July, and eggs are produced on the surface of the water, with 30 to 50 grains in one group. Tiles are arranged closely and do not overlap.
Control methods to strengthen the rice field seedling inspection, if found to have worms, can immediately drain, and then with 2.5% trichlorfon powder fine soil 1 to 1 mixed, every 667m 2 3kg of soil to kill the larvae.