| Phosphorus is one of the essential elements for plant growth,and applying phosphorus fertilizer can effectively promote crop growth and development,and improve crop yield and quality.However,in the production process,in order to pursue yield and economic benefits,the actual amount of fertilizer applied far exceeds the needs of crop production,resulting in low phosphorus fertilizer utilization and a lot of resource waste,causing a series of resource and environmental problems such as water pollution,air pollution,and land degradation.In order to investigate the effects of different fertiliser enhancers on soil nutrients and plant growth and development,nanometer carbon and nanometer humic acid fertiliser synergists were prepared in this study.The fertiliser synergisers were applied in proportion to the fertiliser in pot trials.Five treatments were set up: no fertiliser booster + phosphate fertiliser(T0),biomedical carbon + phosphate fertiliser(T1),nanometer carbon + phosphate fertiliser(T2),humic acid + phosphate fertiliser(T3)and nanometer humic acid + phosphate fertiliser(T4).Field experiments were also conducted,with the following treatments: no phosphate fertilizer(F1),conventional phosphate fertilizer(F2),phosphate fertilizer containing biochar(F3),and phosphate fertilizer containing humic acid(F4),to verify the effects of different efficiency enhancers.The main research results are as follows:(1)The nano-fertilizer synergists can be prepared by ball milling and strong ultrasonic techniques.The surface of the nano-fertilizer synergist is ultrasonically stripped and ballmilled to increase the specific surface area and active functional groups of the fertilizer synergist.The FT-IR characteristic peaks of the nano-size synergist are similar to those of the same common size synergist and have the same structure.The number of active groups(hydroxyl,carboxyl,ester,etc.)of nano-sized synergists is higher than that of normal-sized synergists.After interaction with phosphate fertiliser,the number of each oxygen-containing functional group of the nano-size synergist was significantly reduced and the relative content of phosphate ions was higher than that of the normal-size synergist.(2)The combination of fertiliser synergists(biochar,humic acid,nanometer carbon and nanometer humic acid)and fertilisers effectively promoted soil nutrient content.Compared to the no-fertiliser treatment,the biochar,humic acid,nanometer carbon and nanometer humic acid treatments increased the soil available phosphorus content by 5.57%,11.68%,7.06% and 12.74% respectively.The combination of nanometer fertiliser synergists and fertilisers was more effective than normal size fertiliser synergists in increasing soil available phosphorus content.The soil available phosphorus content of the soil treated with nanometer fertiliser synergists increased by 5.31% to 5.79% compared to the regular size fertiliser synergist treatment.In the nanometer fertiliser synergist treatments,the nanometer humic acid treatment was the most effective,with a 2.03% increase over the nanometer carbon treatment.The height,stem thickness,above-ground and below-ground fresh and dry weights of pepper plants were higher in all fertilizer synergist treatments than in the treatments without fertilizer synergist.This indicates that the fertilizer synergist has a significant effect on the growth and development of pepper plants.Among the different fertiliser synergist treatments,the nanometer fertiliser synergist treatment promoted the growth of pepper better than the normal size fertiliser synergist treatment.The nanometer fertilizer synergist treatment increased 5.22%～14.63%,3.83%～9.20%,0.82%～4.14%,1.47%～6.99%,1.41%～7.30% and18.93%～20.14%,respectively,compared with the normal size fertilizer synergist treatment.All fertilizer synergist treatments significantly increased the height,stem thickness,above-ground and below-ground fresh and dry weights of pepper plants.Compared to no fertilizer synergist treatment,the plants under each fertilizer synergist treatment showed12.33% to 34.79%,5.16% to 22.58%,2.92% to 7.19%,4.11% to 16.67%,17.48% to 26.99%and 3.08% to 30.00% increase in each index respectively.Among the different fertilizer synergist treatments,the plants under the nanometer fertilizer synergist treatment showed an increase of 5.22%～14.63%,3.83%～9.20%,0.82%～4.14%,1.47%～6.99%,1.41%～7.30%and 18.93%～20.14% respectively compared to the normal size fertilizer synergist treatment.Among the nanometer fertilizer synergists,nanometer humic acid was the most effective,increasing the above-ground and below-ground fresh and dry weights of the plants by 4.40%,10.44%,0.74% and 26.12%,respectively,compared to the nanometer carbon treatment.In addition,the fertilizer synergist significantly promoted the increase in total root length,root surface area,root volume and mean diameter of the plant root system,which increased by2.64% to 165.54%,0.55% to 74.35%,13.64% to 28.71% and 14.84% to 34.28%,respectively,compared with the treatment without fertilizer synergist.The promotion effect of different fertilizer synergist treatments on the root system of pepper showed that T4>T3>T2>T1.Among the nanometer fertilizer synergists,nanometer humic acid was the most effective in regulating the root morphology of pepper plants,increasing by 155.09%,71.11%,1.38% and 3.68%,respectively,compared with the nanometer carbon treatment.(3)Applying biomedical carbon and humic acid phosphate fertilizers is more beneficial for increasing soil organic matter,total nitrogen,available phosphorus,and available potassium content,and promoting crop uptake and utilization of N,P,and K.Compared with conventional phosphate fertilizers,the two fertilizers can increase the wheat’s apparent utilization rate by 5.77 and 3.87 percentage points,the agronomic utilization rate by 81.19%and 39.23%,and the partial factor productivity by 30.17% and 14.58%,respectively.The rice’s apparent utilization rate can be increased by 11.19 and 6.71 percentage points,the agronomic utilization rate can be increased by 82.29% and 54.33%,and the partial factor productivity can be increased by 20.61% and 16.45%,respectively.Applying bio-carbon and humic acid phosphate fertilizers can significantly promote the increase of crop height,aboveground and underground dry matter,and increase the yield of wheat and rice.Among them,the effect of the biomedical carbon phosphate fertilizer treatment is the most obvious,and various yield components are also better than other treatments.Compared with other treatments,the wheat yield with bio-carbon phosphate fertilizer treatment can be increased by 13.61% to 107.19%,and the rice yield can be increased by 3.56% to 39.20%.Applying humic acid phosphate fertilizer can also achieve stable and increased yield for wheat and rice.In summary,the nano-fertilizer efficiency enhancer carrier has better effects on soil available phosphorus content,crop growth and development,and nutrient absorption than the conventional size fertilizer efficiency enhancer carrier.In field experiments,fertilizers containing bio-carbon phosphorus and humic acid phosphorus were found to be more effective in improving soil nutrients,promoting crop phosphorus absorption and utilization,and increasing yield compared to conventional phosphorus fertilizers. |
PDF Full Text Request