CN-121970778-A - Preparation method and application of lignin chelated zinc rice seed coating agent

Abstract

The invention discloses a preparation method and application of lignin chelated zinc rice seed coating agent, comprising the steps of weighing quantitative lignin powder, adding zinc salt solution according to a certain proportion after dissolving the lignin powder, carrying out chelation reaction, filtering chelate after the reaction is finished, washing chelate, standing, filtering, drying to obtain lignin chelated zinc, heating and stirring a lignin chelated zinc sample, a composite film forming agent and a plasticizer uniformly, adding nano silicon dioxide, mixing to obtain coating liquid, preserving heat for later use, weighing quantitative rice seeds, immersing the quantitative rice seeds in the coating liquid, stirring, fishing out and air-drying to obtain lignin chelated zinc coated rice seeds. The invention also comprises application of the lignin chelated zinc rice seed coating agent, which can improve the germination capacity of seeds, promote the survival of seedlings and relieve stress resistance. The rice seed coating agent is environment-friendly, can improve the drought resistance of seeds, can effectively protect the seeds, and ensures the higher germination rate of the seeds.

Inventors

• SUN SHAOLONG
• ZHONG YUFENG
• ZHANG LIDAN
• CHEN YUWEN
• LU BOSI
• ZHANG JIAEN

Assignees

• 华南农业大学

Dates

Publication Date

20260505

Application Date

20251223

Claims (7)

1. 1. The preparation method of the lignin chelated zinc rice seed coating agent is characterized by comprising the following steps: s1, weighing a certain amount of soluble zinc salt reagent, adding the soluble zinc salt reagent into water, and stirring and dissolving the soluble zinc salt reagent to obtain zinc-containing solution; s2, accurately weighing quantitative lignin powder, dissolving the lignin powder in water, adding zinc-containing solution, and placing the zinc-containing solution in a reaction kettle for chelation reaction; s3, filtering the chelate after the reaction is finished, and washing, standing, filtering and drying the chelate to obtain a lignin chelated zinc sample; S4, uniformly heating and stirring the lignin chelated zinc sample, the composite film forming agent and the plasticizer, then adding a small amount of nano silicon dioxide, mixing to obtain coating liquid, and preserving heat for later use; and S5, weighing rice seeds with certain quality, immersing the rice seeds in the coating liquid, stirring for a certain time, taking out, spreading the rice seeds in a low-temperature environment for rapid gelation, and air-drying to obtain the lignin chelated zinc coated rice seeds.
2. 2. The method for preparing a lignin chelated zinc rice seed coating agent according to claim 1, wherein the soluble zinc salt reagent in step S1 is one or more of zinc chloride, zinc sulfate and zinc nitrate; The zinc ions of the zinc-containing solution account for 5-8% of the mass of lignin, and the water is secondary water or ultrapure water; The stirring condition is 180-250 rpm, the temperature is 25-40 ℃, and the stirring time is 15-25 min.
3. 3. The method for preparing a lignin chelated zinc rice seed coating agent according to claim 1, wherein the lignin in the step S2 is one or more of alkali lignin, kraft lignin, sulfonate lignin and enzymatic lignin; the mass of the dissolved lignin is 1-8 g/L, and the water is secondary water or ultrapure water; The chelation reaction conditions were 400 rpm, a temperature of 70 ℃, and a reaction time of 40: 40min.
4. 4. The method for preparing a lignin zinc chelate rice seed coating according to claim 1, wherein the drying temperature in S3 is 50 ℃.
5. 5. The method for preparing the lignin chelated zinc rice seed coating agent according to claim 1, wherein the composite film forming agent in the step S4 comprises one or more of polyvinyl alcohol, sodium carboxymethylcellulose, sodium alginate, chitosan, xanthan gum, carrageenan, gelatin, pectin and acacia, and the dosage is 2-6% of the total mass by mass percent; the plasticizer comprises one or two of polyethylene glycol, propylene glycol and glycerol, and the dosage of the plasticizer is 1-4% of the total mass by mass percent; The stirring condition is 400 rpm, the temperature is 70 ℃, and the stirring time is 1 h; the consumption of the nano silicon dioxide is 0.2-0.5% by mass percent; The mixing condition is 400 rpm, the temperature is 40 ℃ and the time is 15-20 min; The temperature-keeping condition is 40 ℃.
6. 6. The method for preparing a lignin zinc-chelate rice seed coating agent according to claim 1, wherein the mass ratio of the coating liquid to the rice seeds in the step S5 is 1:100-300; the stirring condition is 100-200 rpm, the temperature is 25-40 ℃, and the stirring time is 5-10 min; The low-temperature environment is preferably 0-5 ℃, and the air drying time is preferably 48 h.
7. 7. The coating agent prepared by the preparation method of the lignin zinc chelate rice seed coating agent is characterized by being applied to improving the germination capacity of seeds, promoting the survival of seedlings and relieving stress resistance.

Description

Preparation method and application of lignin chelated zinc rice seed coating agent Technical Field The invention relates to the technical field of seed coating agents, in particular to a preparation method and application of a lignin chelated zinc rice seed coating agent. Background With the increase of global population and the aggravation of cultivated land resource constraint, the seed coating technology is undergoing transformation from traditional chemical treatment to green functionalization as a key measure for improving agricultural production efficiency and guaranteeing grain safety, which is both an opportunity and a challenge for the development of seed coating technology in China. Rice plays an important role in grain structure and human life, and the yield and quality of the rice are directly related to grain safety. However, in conventional rice planting, problems of low survival rate of seedlings, low utilization rate of nutrient elements and the like are often faced, and the problems severely limit sustainable development of the rice industry. The rice is one of the most sensitive crops to zinc, the zinc is used as a cofactor of a plurality of enzymes to participate in photosynthesis, protein synthesis and hormone metabolism, and the zinc deficiency in the seedling stage of the rice can cause the problems of root system dysplasia, albino seedling and the like, thereby seriously influencing the later-stage yield formation. According to statistics, about 50% of paddy soil in China has potential zinc deficiency, especially in paddy fields under lime soil and flooding conditions, the zinc availability is lower, and the phenomenon of zinc deficiency is more common. The traditional soil zinc fertilizer is easy to fix by soil, and seed coated zinc can be directly absorbed by seedlings, so that the nutrient utilization efficiency is improved. Therefore, zinc can be accurately supplemented by a seed coating technology, zinc nutrition is provided in the most sensitive germination period of rice, and a high-yield foundation is laid. Lignin is used as a natural polymer material with second most abundant natural, and has good biocompatibility and degradability. The research shows that lignin molecules contain abundant active groups such as phenolic hydroxyl groups, carboxyl groups and the like, and can form stable chelate with zinc ions, and the application of the chelate structure to seed germination has the advantages that firstly, the stability of zinc element is improved, soil fixation is reduced, secondly, the release rate of zinc is controlled, the fertilizer efficiency period is prolonged, thirdly, the transportation efficiency of zinc in plants is enhanced, and fourthly, the lignin has the effect of promoting seed germination. Furthermore, more and more researchers have demonstrated that elemental zinc has a very important role in seed germination. Zinc initiation is a key technology for activating seed metabolism and relieving zinc deficiency stress with low cost and high efficiency, and zinc promotes seed germination and seedling growth through triple mechanisms of metabolic activation, stress resistance enhancement and nutrition supply. However, in the currently disclosed seed coating technology, CN101665383B partially solves the problem of trace element loss through a physical embedding and slow-release film technology, but compared with the modern chelating technology, the technology still has obvious defects in chemical stability, element targeted release and long-acting property, and CN111771454A discloses a slow-release seed coating agent based on papermaking black liquor, but is not specially optimized for zinc element. In particular to the chelation technology of lignin and zinc, the prior art still has the technical bottlenecks of low chelation rate, poor coating adhesion force and the like. Therefore, the development of the lignin chelated zinc seed coating agent with high efficiency and environmental protection has important research significance. The lignin chelated zinc coated rice seed technology provided by the invention not only can obviously improve the germination rate and seedling uniformity of rice seeds, but also can realize the accurate supply of zinc element, reduce the fertilizer consumption, and has important economic value and ecological value. The invention has high efficiency, low toxicity, simple production and low cost, and has obvious improvement on zinc utilization rate, slow release performance, coating stability and the like. Disclosure of Invention The invention aims to provide a preparation method and application of a lignin chelated zinc rice seed coating agent, so as to solve the problems in the background technology. In order to achieve the above purpose, the present invention provides the following technical solutions: The preparation method of the lignin chelated zinc rice seed coating agent comprises the following steps: s1, weighing a certain amount of