Scientific name Orseoia oryzae (Wood-Mason) Diptera, Aconitum. Alias ​​rice fly. Distributed in Guangdong, Guangxi, Fujian, Yunnan, Guizhou, Hainan, Jiangxi, Hunan and Taiwan. According to observation in Guangchang County, Jiangxi Province, after the worm enters Guangchang County from Shicheng County, it still spreads northwards at a speed of 10 to 20km per year.
Host rice, Lee's cricket and so on.
Characteristics of larvae larvae eat rice growth point sap, causing damage to the rice seedlings base enlargement, then the heart leaves to stop growing and the leaf sheath lengthened to form a light green hollow onion tube, the onion tube stretched out to form "standard onion." Rice can be affected from the seedling stage to the young ear formation stage. If the damage is heavy, it cannot be heading, and almost all of them form “onion†or distortion.
Morphological characteristics Adult body length 3.5-4.8mm, shape like mosquitoes, light red, 15 antennae, yellow, 1st and 2nd section spherical, 3rd 14th section of the shape of male and female are different: female is nearly cylindrical, Slightly concave in the center; male mosquitoes like gourd-shaped, in the middle contraction, as if 2 sections. The chest plate is well-developed in the chest, and the abdomen has a spindle-shaped bulge like a hump. Forewing transparent with 4 wings veins. The egg is about 0.5mm long, long oval, early white, later orange red or purple. Larvae last instar larvae body length 4-4.5mm, spindle-shaped; The larvae were 3rd instar, 1st instar and approximately 0.78mm long; the 2nd instar spindle length was approximately 1.3mm; the 3rd instar was similar to the 2nd instar, and its body length was approximately 3.3mm. Oval shape, light red to reddish-brown, 3.5-4.5mm long.
Living habits Guangdong Lianshan 6-7 generations, Guangdong Conghua, Guangxi, Jiangxi, Yunnan, Fujian 7-8 generation, Guangdong Foshan, Zhongshan 8-9 generation, Hainan 12-13 generations. The larvae overwinter on weeds such as grasses, ratooning rice, and Lee's clams at the fields and at the sides of the valley. In the 7th and 8th generations of the year, adult overwintering occurs from late March to early April. After the emergence, the adult flies to the nearby early rice. It is difficult to separate the algebra from the second generation since the second generation. The adult emergence period is more obvious. The number of people in the first and second generations is generally small, and the number increases after three generations. From July to October, Putian and Honda of middle rice, single-season late rice and double-season rice are vulnerable to serious damage. On the evening of the adult emergence, the males mate, and the males mate for many times. The females only mate once. The eggs are spawned on the young leaves near the surface. Each female produces 100-150 eggs. The females have phototaxis, so they appear on the traplights. Peak days mean the peak days of spawning in the field. The newly hatched larvae migrate under the moist dew on the leaves and invade from the leaf sheath gap or the lingual rim edge and begin to injure the growth point. After the growth point is damaged, the heart leaves cease to grow, and the sheath expands into a tube, that is, the “standard onion†appears. The larvae in the tube have been cleared. Before the emergence, the head of the corpus callosum rose upward, and the cormorants rose to the top of the onion tube. The corona was broken off with a forehead, leaving a white pod at the exit. The insects are so wet that they are not able to tolerate drought. The temperature is 25-29°C and the relative humidity is higher than 80%. The cultivation system on the production is complex, and single- and double-season rice-planting areas have serious rice blasts. Natural enemies include spiders, crickets, ants, walking frogs, frogs, and black-shouldered black bees.
Prevention and control methods The strategy for controlling thin mosquitoes in rice is to “grab the fields, protect the Honda, control the damage, put the three barriers, and focus on preventing the main damages.†(1) Selection of insect-resistant varieties such as anti-mosquito 1, anti-mosquito 2, Shanyou 999, Shuifu 17, etc. (2) Spring to eradicate paddy field and reclaimed rice to reduce overwintering. The single- and double-season rice mixed-planting area was changed to a pure double-cropping rice area according to local conditions. The sowing date and planting period were adjusted to avoid the peak period of adult egg laying. (3) Take care to prevent seedlings from worms, if necessary, dip the roots with a solution of 90% crystals of trichlorfon 800 times or 40% dimethoate 800 times and cover with a plastic film for 5 hours before transplanting. (4) When the late rice is sown, 3 kg of 3% dianbane granules per 667m2 is sprayed, and 7-8 days before seedlings transplanting, 40% dimethoate EC 250ml, and 20 kg of fine dry earth can be used as poisonous soil applicator. effective. (5) Do a good job of monitoring and forecasting insect pests, and make timely and accurate predictions of the occurrence of the major damages of thin-skin mosquitoes. (6) Strengthen agricultural control and fitness control. 1 Summer and summer harvest season, timely harvesting of early rice fields, eradicating field bases, ditching weeds, and using muddy fields, etc., can eradicate the source of insects, reduce roots, and reduce insect population
number. 8 Rationally mix mid- and early-maturing hybrid rice. Such as the Guigui 34, Boyou 49 and other combinations. 8 Do not broadcast late rice bran in early rice Honda, advocate centralized and unified sowing of seedlings for late rice, and promote flooding, dry management, and drought breeding. To prevent the summer and autumn seasons, the green fields of yellow rice fields coexist, or the "green roads" of the rice fields. 4 Use of resistant resources, demonstration and promotion of planting anti-mosquito species such as plant selection number one. 6 pay attention to protect the use of natural enemies. 8 Scientific drug use. Putian drug prevention and control mainly uses poisonous soil surface application methods. In order to raise the needle to the second leaf one needle period or 5 to 7 days before transplanting, every 667m2 use 10% Yishubao or 5% icas, 3% Milur granules 1.25-1.5kg, also available 3% Carbofuran or 3% methyl isofluosad granules 3.5-4kg soil mix 10-15kg evenly applied. In the field of pesticide application, Putian should maintain a shallow layer of water and allow it to dry naturally, allowing it to be taken to the field. This is to prevent seedlings from becoming infected with insects. After dipping the roots with 90% crystals of dichlorfon 800 times or 40% dimethoate 500 times, Cover with a film for 5 hours and transplant. 7 During the period from the beginning of the adult to the peak of egg hatching, when the belly began to appear, use 90% crystals of trichlorfon 200g plus 40% dimethoate EC 100ml per 667m2, and mix with 20kg soil. 3% 3% carbofuran granules can also be used for deep application, keeping 3cm shallow water layer. 8 Honda Control After the Honda seedlings return to green, they should be applied within 7 to 20 days after sowing. The control of key pesticides is generally only applied to plots that coincide with the invasion period of rice gall midges in the effective tillering stage. Drug and fertilizer, to kill insects, attack with fertilizer, promote glutinous into a spike. The method of administration is the same as the field period, but the dosage should be increased appropriately. Pay attention to the use of insecticides with strong conductivity and killing eggs. Fill the water with worker and peasant type 16 sprayer and add 30% of the insecticide 5ml or 50% of 20% killing enemy treasure. Also use 40% omethoate or 40% dimethoate, 50% methamidophos EC 1000 times, 36 %Spiraea fuliginea oil spray 1000-1500 times, every 667m2 spray good liquid 50-60kg, control rice thin mosquitoes, and cure rice fly stalks, control effect 90% to 95%.