Development Of The Wedge Slow-Release Fertilizer For Flower And Its Release Characteristics

Flowers need a lot of fertilizer to grow,but most of the flower fertilizers on the market are quick-acting fertilizers,with low nutrient utilization,serious waste and pollution.Long-term use can also cause problems such as soil acidification.In addition,the traditional flower fertilizer is mostly small particles and the application method is mostly buried deep in the hole,which is laborious and time-consuming,and easy to damage the root system of plants.To address the lack of flower-specific slow-release fertilizers in the market.This study prepared a wedge-shaped flower slow-release fertilizer by extrusion granulation using urea formaldehyde,potassium feldspar,ammonium polyphosphate and other raw materials.The shape of the fertilizer is wide at the top and sharp at the bottom and easy to insert directly into the soil.The hardness,moisture absorption test,wear-resistant teat were performed to obtain the best fertilizer formula;The nutrient release characteristics of the wedge-shaped flower slow-release fertilizer and its ammonia volatilization characteristics in the substrate and soil was measured.Finally,the best application method of the wedge-shaped flower slow-release fertilizer on Gilly Red was determined by varying the application amount（full and 50%reduction）,the application depth（0 and 5 cm）,and the application distance from the plant（3and 5 cm）in combination with the potting test.This study created a long-lasting,high-efficiency and easy-to-apply wedge slow-release fertilizer for flowers,which can provide research parameters for the development of various types of flower slow-release fertilizers and fill the gap in the development of flower slow-release fertilizers.The main research results are as follows:1.In this experiment,two nutrient ratios（ratio I,15-15-15;ratio II,12-8-10）of wedge-shaped flower slow-release fertilizers were prepared using raw materials such as urea formaldehyde,AP,SK,potassium sulfate,magnesium sulfate,potassium sulfate and different additives（talc,montmorillonite,alabaster,gypsum,lime,bentonite）.The wedge-shaped flower slow-release fertilizers（SF4,SF11）with additives of 2.5% magnesium sulfate,2.5%zinc sulfate and 5% talc were screened by hardness,abrasion and moisture absorption tests.Among them,the hardness of SF4 is 469.3N,the residual rate after grinding is 99.93%,and the cumulative moisture absorption rate of 7d is 14.5%;the hardness of SF11 is 447.4N,the residual rate after grinding is 98.38%,and the cumulative moisture absorption rate of 7d is12.43%.2.The SF4 and SF11 from the primary selection were studied under different hydrostatic temperatures for release characteristics.The results showed that the release trends of nitrogen,phosphorus and potassium of SF4 and SF11 in different temperatures were basically the same,and could be roughly divided into two stages of rapid release and smooth release,i.e.,the nutrients were released rapidly in the first 5 d,and released smoothly and slowly after 5 d.The two nutrient distribution ratios of wedge flower slow release fertilizer at 25℃ and 40℃nutrient release period are more than 105 d,can effectively extend the nutrient release period.3.Ammonia volatilization experiments were carried out in soil and substrate for wedge-type flower slow-release fertilizers（SF4 and SF11）,and powder-type fast-acting fertilizers were used as controls.ammonia volatilization rate of SF4 and SF11 in the substrate was stable at 0.055-0.06 mg/d after 7d.ammonia volatilization rate of SF4 was stable at0.008-0.01 mg/d after 7d,and ammonia volatilization rate of SF11 was stable at 0.065 mg/d after 7 d.The rate of ammonia volatilization was stable at 0.065-0.075 mg/d after 7 d.The rate of ammonia volatilization and the total amount of ammonia volatilization were both at very low levels,and the volatilization loss of nitrogen was significantly reduced compared with that of powder-type quick-acting fertilizer.4.Two application rates（full and 50% reduction）,two application distances（3 cm and 5cm from the plant）and two application depths（surface application and 5 cm deep application）were set to investigate the best application method and application effect of slow-release fertilizer for flowers.The leaf length,leaf width,leaf area,anthocyanin,soluble sugar,of all the wedge-type flower slow-release fertilizer treatment increased by 26.34%,26.93%,15.735%,92.42% and 25.15% on average,respectively compared with the powder-type fast-release fertilizer treatment.Full application of wedge flower slow-release fertilizer increased the number of Gilly Red leaves by 29.79%,leaf area by 14.58%,and anthocyanin content by 40.16% on average compared with 50% reduction application;5 cm from the plant increased the Gilly Red leaf length by 19.68%,leaf area by 20.86%,and anthocyanin content by 15.951% on average compared with 3 cm from the plant;5 cm deep application increased the Gilly Red leaf length by 47.22% on average compared with surface application.Red anthocyanin content by 47.22% and leaf area by 17.11% on average compared with surface application.