Application Case

Soil Health Enviromental

Effects of seaweed liquid fertilizer on banana growth

September 01, 2022

【Objective 】To reveal the effect of seaweed alkaline fertilizer on banana growth and its promotion mechanism, and provide a theoretical basis for the development, popularization and application of the seaweed alkaline fertilizer.

【Method 】Banana pot experiment was carried out.

Banana biomass, soil microorganism, enzyme activity, root activity, soil nitrogen and phosphorus nutrient content were measured to identify the efficacy of seaweed alkaline liquid fertilizer.

【Result 】Compared with conventional compound fertilizer and non-seaweed alkaline liquid fertilizer, seaweed alkaline fertilizer could promote banana growth and its biomass, increase its root activity.

The soil urease and acid phosphatase activities, soil mineral nitrogen and available phosphorus content, number of bacteria, fungi and actinomyces increased obviously. Leaf area and biomass increased by 50–100 cm 2 and 10%–21%, respectively. The root activity increased by 89%–188%. Soil urease and acid phosphatase activity increased by 25%–91% and 2.4–3.5 times, individually. The number of soil bacteria, fungi and actinomycetes of seaweed alkaline liquid fertilizer increased by 1.6–14.4, 1.7–26.7 and 2.3–3.8 times compared to those of compound fertilizer treatment, respectively. The corresponding data of the seaweed alkaline liquid fertilizer were 3.0–10.6, 3.9–56.0 and 1.2–2.0 times of those of alkaline liquid fertilizer without seaweed, individually.

【Conclusion 】

Application of seaweed alkaline liquid compound fertilizer could obviously promote banana growth. The mechanism was that the acidic soil environment was improved by the alkaline fertilizer and then the soil microbial diversity increased on the one hand; The seaweed acid increased soil urease and acid phosphatase activities, the soil nitrogen and phosphorus nutritional status were improved on the other hand to increase soil fertility. Therefore, the synergistic application of seaweed and alkaline liquid fertilizer is a rational measure to supply nutrients to banana and improve soil fertility.

Effects of seaweed liquid fertilizer on banana growth

At present, the problem of cultivated land in my country is the degradation of cultivated land quality caused by soil acidification and lack of soil organic matter. The key to improving the quality of arable land and ensuring the healthy growth and high-quality and high-yield of crops lies in improving the pH value of the soil that is too low, preventing further acidification of the soil, and increasing soil organic matter.

The direct cause of acidification of arable land in my country is the long-term large, excessive and unreasonable application of chemical acid fertilizers (such as compound fertilizers) and physiological acid fertilizers (such as urea, ammonium nitrogen fertilizer). In the past 40 years, the pH value of red soil has dropped from 6.0-6.5 in the second soil census to about 5.5 at present, with an average drop of 0.2-0.5 units, and some soils dropped by 1.5-2 units. Soil acidification leads to the activation and contamination of heavy metals such as soil Cd, and threatens human health through the food chain.

The reason for the lack of soil organic matter is that the quality of organic fertilizers applied to the soil is uneven, and many organic fertilizers lack organic matter, and the effect of improving soil fertility is not good. Although the control of soil acidification and its resulting heavy metal pollution, increasing soil organic matter and improving soil fertility are the top priorities of the country's arable land conservation, for a long time, the method to control soil acidification is to apply lime and calcareous industrial waste, and long-term use Lime not only leads to soil compaction, but the improvement effect is not lasting, and it is easy to return to acid [33]; the application of calcareous industrial waste may cause new soil pollution problems.

 

Therefore, in order to control soil acid, soil heavy metal pollution and improve soil fertility, it is necessary to start from green inputs, that is, to develop and apply new alkaline fertilizers to replace conventional acidic or physiologically acidic fertilizers, so as to achieve the goal of fertilizing and providing nutrients to crops. while improving soil acidity. That is to say, the fundamental way to solve the problem of soil acidification and Cd pollution caused by large and unreasonable fertilization is to change the acidity and alkalinity of fertilizers, and at the same time combine seaweed with fertilizers to develop seaweed alkaline fertilizers, which is The purpose of this study. Previous studies have proved that the alkalinity of alkaline fertilizers can neutralize the active acid and latent acid of the soil and improve the soil acidity.

Compared with ordinary fertilizers, alkaline fertilizers also have the function of disease resistance and growth promotion. If seaweed is attached to the fertilizer, the organic matter of the soil can be directly increased, which can not only fertilize and improve the soil, but also provide growth regulators for crops. Therefore, seaweed alkaline liquid compound fertilizer is a functional fertilizer that can replace conventional compound fertilizer. The results of this study prove that the application of seaweed alkaline liquid fertilizer is beneficial to promote the growth of banana seedlings, including the promotion of plant height, stem crude and chlorophyll content, increase the biomass of banana seedlings, and lay a good foundation for high yield and high quality of bananas.

The results of this study also showed that: after the application of seaweed alkaline fertilizer, the alkalinity of the fertilizer improved the soil acidic environment, making it favorable for soil microbial diversity; the seaweed of the fertilizer increased the activities of urease and acid phosphatase in the soil, thereby increasing the soil microbial diversity. Mineral nitrogen and available phosphorus and other nutrients; the synergistic effect of alkaline environment and seaweed is conducive to improving the soil environment and soil nutrient status, increasing the root vigor of bananas, thereby promoting the growth of bananas.

Therefore, we believe that the development and application of seaweed alkaline liquid fertilizer is an effective measure to control fertilizer with fertilizer, to improve soil with fertilizer to control acid, and to fertilize soil and nourish crops.

Compared with conventional fertilizers, the application of seaweed alkaline liquid fertilizer can significantly promote the growth of bananas. The mechanism is that on the one hand, the alkalinity of the fertilizer improves the soil acid environment, increases the number of soil bacteria, fungi and actinomycetes, and promotes the diversity of soil microorganisms. On the other hand, the seaweed in the fertilizer increases the activities of urease and acid phosphatase in the soil, improves the nitrogen and phosphorus nutrition of the soil and is beneficial to the growth of bananas. In the future, the related fields can further carry out in-depth research on the manufacturing technology, application effect and mechanism of solid seaweed alkaline fertilizer.