Recently, several readers in Suqian, Yancheng and other places called to reflect the occurrence of yellow dry leaves and rust spots on the leaves of dry rice seedlings.
On May 21, Cao Changya from Xinhe Town, Cangzhou City, came to the telephone and said: The rice seedlings of the dry nursery began to develop after the last rain. The yellow leaves of the diseased seedlings, the dead leaves and the leaves died in the field, and the diseased plant rate reached 30. %. Rice seedlings are now in the 2-leaf 1 heart period. He asked what kind of diseases the rice seedlings were harmed and how to prevent them.
Wang Ailin, from Bincang Town, Tinghu District, Yancheng City, came to the telephone to report that the yellow leaves appeared on his 2 acres of hybrid rice. There were large rust-colored spots of sesame on the leaves of the diseased seedlings. The tips of the leaves were scorching, with less white roots and more black roots. There is no white root, which occurs in one pond and one pond, and the diseased plant rate reaches 20%. He asked what diseases the rice had and how to prevent it.
On May 25th, Liu Donglai from Machang Town in Suiyang County reported that the phenomenon of leaf reddening occurred in the two-leaf and one-heart stage of the large area of ​​dry rice seedlings. The rust spots appeared on the leaves of the diseased seedlings, and the roots were yellow, with no white roots. Green dead seedlings, the disease rate of 60%. After spraying, potassium dihydrogen phosphate solution was sprayed and the humidity in the field was relatively high. He asked if it can be sprayed with prochloraz, venom, propiconazole and other drugs.
On May 26, Wang Weiling of Suling District, Suqian City, said in a telephone call that more than 20 rural households reported that rice seedlings in dry conditions had symptoms of yellowing at the 2 leaf 1 heart stage, and the tip of the diseased seedling was yellow and dry. There are rust spots on the top and the roots are well developed. The rate of diseased plants reaches 50%-60%. This situation started to happen after rain, and it developed rapidly. He asked what happened to rice seedlings.
Zhang Jun, San Zhuang Township, Puyang County, said: The local rice seedlings on the 100-mu-mu crop have begun to develop in the past few days. The first leaves of the diseased seedlings have died of the entire leaf, and are curled up. The tip of the upper leaf blade has died and there is rust on the diseased leaf. spot. At present, seedlings are in the 3-leaf 1 heart period. A similar situation occurred in previous years, but not so severe this year, after spraying foliar fertilizers such as potassium dihydrogen phosphate, most diseased seedlings can recover. He asked how the prevention and treatment of rice seedlings occurred after this situation.
Liu Wenquan, Yu Town, Liyang County, came to the telephone to report that the local drought-infested rice seedlings were generally infected. The diseased seedling leaves died with dark brown spots on them and the roots developed well. The diseased plant rate reached 40%. Most of the local rice seedlings are fed with organic manure such as uncomminuted pig manure, and a small number of farmers use quick-acting fertilizers. He asked what the diseases of rice seedlings were and how to prevent them.
Readers in Suqian area reported that yellow rice seedlings had yellow leaves and rust spots. The reporter interviewed Suqian Plant Protection Station experts by telephone. According to reports, in the near future, there are also many farmers with the rice seedlings to the Suqian Plant Protection Station consultation, the diagnosis of disease mostly caused by lack of factors. The diseased seedlings began yellowing from the midrib of the leaves, with rusty rust on the top. The symptoms were caused by zinc deficiency. The diseased seedlings grew yellow from the tip of the leaf and had rust spots on the top. The symptoms were caused by potassium deficiency and phosphorus deficiency. The main reasons for the lack of nutrients in paddy seedlings for dry rice production are: Firstly, compound fertilizers with low potassium content are commonly used in production; potassium is used in small quantities, and potassium deficiency symptoms occur in seedlings; second, unfertilized organic fertilizers are used, and fertilizers mature after raining. Fermentation, burned seedling roots, decreased root-fertility absorption capacity; third, rice seedlings in 2-3 leaf stage were in weaning stage, incomplete root development, coupled with more rainy days in the near future, high humidity in the field, affecting the ability of root absorption, Causes the emergence of deficiency symptoms.
After the above-mentioned diseases occur in rice, dry roots with good roots can be supplemented with appropriate amounts of potassium sulfate, potassium chloride, zinc sulfate, superphosphate, and other fertilizers; poor root can be sprayed with 1% potassium chloride solution, 0.2% potassium dihydrogen sulfate Solution and other foliar fertilizers. The use of Baishili and other humate leaf foliar fertilizers will help promote the recovery of seedlings.
In addition, the occurrence of brown spots in the rice seedling leaves may also be caused by diseases such as rice blast, leaf spot disease, and the like. This can be used for the prevention of two diseases such as rice bran, kasugamycin and prochloraz.
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