Phosphorus is one of the 17 essential plant nutrients . “Indispensable ” means plants lack the element , normally stunted , unable to complete its life cycle , only a supplement to prevent the development of this element of symptoms . Therefore , phosphorus for plant nutrition irreplaceable . You can say : “No phosphorus, no food .”
When deficiency , the plants grow slowly, little old, thin stems erect, branched or fewer tillers . Ye was dark green or gray-green and dull, often with purple stems and leaves . Poor root development , easy to aging . Deficiency fewer fruits and seeds of plants and small , mature delayed, yield and quality are reduced. The past 30 years , due to the large number of inputs of fertilizer , irrigation and soil phosphorus content of accumulation , crop deficiency appears only in some areas. According to Bing-Qiang Zhao and other ” sustainable use of soil fertilization system with ” long-term monitoring studies to locate a book fertilizers showed that the vast majority of 3-5 years in a row is not the type of soil P fertilizer , crop will be severely cut. But when the phosphorus resource depletion, P fertilizer is generally inadequate , this deficiency symptoms that may occur will be widespread . Then , clearly showing the ” no phosphorus, no food ” signs.
Phosphorus is present in all living cells of plants , the plants involved in a variety of critical functions, including energy conversion , photosynthesis, plant nutrients in the body intergenerational transport and plant genetics. Therefore, maintaining the current level of soil phosphorus , when major grain ( maize, rice, wheat ) yields three are 10 tons / ha , then it will mean from the removal of soil per hectare 60-80 kg P2O5. Substantially between crop yield and nutrient requirement linear function , the higher the need to make phosphate fertilizer production more . High-yielding maize required to provide adequate soil phosphorus ; soybean P fertilizer effect is obvious ; wheat seedling tiller need to promote water-soluble phosphorus , nitrogen and phosphorus combined application for optimum grain yield ; Phosphorus is profitable cultivation of potatoes indispensable nutrients , even in the phosphorus-rich soil, phosphorus generally increase .
Fertilizer can improve crop resistance to diseases, phosphorus can promote the rapid development of seedling root ; root rot can cause wheat, barley production is declining dramatically , reduce fertilizer application root rot infection ; phosphorus can reduce the incidence of corn smut rate . Reduce phosphorus and potassium combined application of stem rot of rice , sugarcane reduce brown stripe disease .
Phosphorus can improve product quality ; corn P fertilizer in addition to increase production , but also to reduce the grain moisture content, save drying costs ; phosphorus can increase the survival rate of winter wheat , winter crops and upland rice seedlings increased phosphorus can increase the resistance of crops and adaptability to the external environment , can make a robust crop less susceptible to frost damage roots ; U.S. experience shows that phosphorus can improve the quality of orange juice , orange juice weight increase of 7 % fruit sweetness increased by 8% thinner rind , substandard goods eliminate fruit weight decreased by 12% ; deficiency can lead to slow growth of the vines , the result string is reduced.
Phosphorus can affect crop maturation process can accelerate the growth of wheat , so that mature early 4 to 7 days , more than a few days, right after the crop sowing is very important , early vegetables, fruits in the market price is higher. Applying enough fertilizer on crop yield, quality , resistance has greatly improved. Vision test , once phosphorus resource depletion , what will be the consequences ? Thus, China’s phosphorus resources should be steady and sustainable use .
Since 1975 , China’s investment in phosphorus farmland ( including fertilizer , organic fertilizer inputs ) is greater than the amount of crops with soil accumulation of phosphorus in the state . Cumulative increase almost doubling every 10 years , according to Professor Zhang Weifeng , China Agricultural University, estimates that the current national soil phosphorus accumulation of about 90 million tP2O5. On the other hand , the soil , the trace element deficiencies and presents the state . 2000 farmland ecosystem , superphosphate production of 13.58 million t, into 2,830,000 t of sulfur , fertilizers accounted for 90% of the total sulfur into 40 percent of the total revenue of sulfur in the soil . The 2012 China produced 15.55 million superphosphate t, the average sulfur content of 11.6% , 1.8 million t of sulfur into the farmland ecosystem only , resulting in the increase of China’s lack of sulfur soil area ; 2000 superphosphate , calcium magnesium phosphate into soil calcium 5,350,000 t, 2012 only brought 3.12 million t; 2000 FCMP yield 3,856,000 t, into magnesium 337,000 t, 2012å¹´FCMP production 1.33 million t, 96,000 t of magnesium into only . Calcium , magnesium oxide is a basic compound , at present, is in need of application of basic fertilizer acidification .
Over the past decade , the rapid accumulation of phosphorus in the soil , root crops phosphate ion concentration is too high , zinc , manganese, iron, copper ions and phosphate ions combine to form phosphate precipitation in the root tissue , causing crop micronutrient deficiencies ; the past 10 years due to changes in product mix fertilizer , resulting in soil calcium, magnesium, sulfur deficiency is very prominent in the amount of elements .
Studies have shown that water-soluble fertilizer is important, but difficult to find data demonstrate that the rate of over 60% water-soluble fertilizer superiority. Therefore , it should take into account the variety of phosphate ammonium phosphate , calcium phosphate , calcium magnesium phosphate balanced development of their own characteristics , but not been neglected.(http://www.lubonchem.com supply)
