Prevention of phytotoxicity caused by Bordeaux fluid
Piperaquinea Phosphate,Pharmaceutical Chemical,Trimethoprim Tablet Glutathione for Skin Whitening & Beauty Co., Ltd. , http://www.nsantibiotics.com
Bordeaux liquid is the longest application time in fruit trees, the widest range of applications, the most stable drug efficacy, and has not yet produced broad-spectrum protective fungicides. The active ingredient is basic copper sulfate. In the production practice, some fruit growers often suffer from phytotoxicity due to improper preparation or use, and they should be taken care of and prevented. First, the Bordeaux liquid phytotoxicity reasons 1, the preparation of Bordeaux mixture, copper sulfate dissolved incomplete, medication with the dregs sprayed on the fruit, the fruit will appear red brown damage spots, reduce the value of fruit products. 2. The use of Bordeaux mixture in the young apple fruit and mature fruits will cause rust spots on the fruit surface, rough skin, reduced smoothness, and reduced appearance quality of the fruit. 3, peach, apricot, plum tree is sensitive to copper in the growing season, the use of Bordeaux liquid is prone to copper ion poisoning, resulting in falling leaves, fruit drop. When the amount of lime in the Bordeaux mixture is less than the multiple type, apples, especially golden crown varieties, hawthorn, and persimmon trees are prone to phytotoxicity. When the amount of lime is higher than that of the equal amount formula, grape longan, seedless purple, Dendrobium and other species are prone to injury. 4. Bordeaux mixture is mixed with lime sulfur, trehalose, etc., or used alternately. The interval time is too short, which is easy to produce phytotoxicity. 5, Bordeaux liquid used in high temperature conditions, easily caused by lime caused by phytotoxicity. After spraying, the liquid did not dry out and it rained or the leaves were dry and not sprayed. Because of the dissociation degree of copper and the permeability of leaves, the content of soluble copper on the leaves increased rapidly, causing burns to the leaves. After a certain period of time, Bordeaux mixture will cause the content of soluble copper on the leaf surface to increase rapidly after a period of time when it is used, causing the leaves to be coked, which will cause so-called storm damage. Second, the prevention of Bordeaux fluid production injury measures 1, to select the preparation of raw materials. When preparing Bordeaux mixture, high-quality, pure, white, light-weight lump lime should be used. Copper sulfate should be used as a blue crystal product. If it is yellow or green powder, it should not be used. 2, strictly follow the preparation process. When dispensing, copper sulfate is first opened in a non-metallic container with an appropriate amount of hot water, then filtered, and 90% of the total amount of water is added, and the residue is filtered out after being opened. The filtered lime solution (with 10% water) is poured into a large cylinder or concrete pool, and then the copper sulfate solution is slowly poured into the lime liquor in the cylinder or the cement pool, and the mixture is stirred vigorously and poured. Continue stirring for another 2-3 minutes. Never pour lime into copper sulfate solution. Otherwise, the formulated liquid will precipitate rapidly and prone to phytotoxicity. In addition, the best use of the liquid immediately after use, should not be put for a long time. 3, pay attention to the spraying period. The Bordeaux mixture should not be used within 1 month after the apple is dropped and when the fruit is near mature to prevent rust on the fruit surface or affect the coloration. When spraying fungicides at this stage, carbendazim and thiophanate-methyl may be used. 4, different species to use different concentrations. Fruits such as peaches, apricots, and plums, which are particularly sensitive to copper ions, cannot use Bordeaux mixture during the growing season. For other tree species, different formulations and ratios should be used according to their sensitivity. For species sensitive to copper, lime multiples or multiples can be used. For pears that are less sensitive to lime or copper, equal proportions of lime may be used. Lime-sensitive grapes that are tolerant to copper use a half-calorie ratio. 5, reasonable mix. Bordeaux mixture cannot be used in combination with lime sulfur, bacteriocin etc. Bordeaux mixture with organic phosphorus pesticides should be used with caution, can be mixed with the use. Only 10 days after the spray of lime sulfur was sprayed on the Bordeaux mixture, and sprayed with Bordeaux mixture for 20-30 days before lime sulfur was sprayed. 6, pay attention to the changes in the weather. Bordeaux spray should be selected when clear, no dew. Spraying in the summer should avoid high temperatures at noon, so as to prevent lime from causing phytotoxicity at high temperatures. In the rainy season, it is necessary to avoid stormy weather as much as possible, and at the same time, it is necessary to appropriately increase the amount and proportion of lime during dispensing.