Using plant biostimulants to enhance plant production can be a great idea. They can help increase the uptake of water and nutrients by plants, and they can also help beneficial microorganisms grow.
Increased availability of nutrients in soil
Agricultural biostimulants are plant-based materials that improve the uptake and availability of nutrients in soil for plant production. They can also improve tolerance to abiotic stress. The biostimulants are made from a variety of natural materials, including plant extracts and amino acids. Biostimulants can also improve nutrient use efficiency, increase crop quality, reduce water stress, and improve crop yields.
There are two main categories of plant biostimulants. The first category contains protein sources, such as crustacean shells and epithelial tissue. Proteins can be hydrolyzed into amino acids, which can be directly absorbed by soil microorganisms. The second category is made from a variety of raw material sources, including waste products, animal products, and crop residues.
The present study evaluated the effect of seaweed and amino acids based biostimulants on soil microbial communities. The aim was to explore the way in which the two biostimulants increase the mineralization rate of organic carbon in soil. This study was performed in soil from Kerbernez, Plomelin, France. The soil was sieved to remove soil particles and then stored at 4 degC.
After 49 days of treatment, there was a significant increase in the richness and diversity of active fungi. These results suggest that biostimulants act on soil microorganisms in the same way as the natural regulators of microbial communities. However, the effects are delayed, especially on soil active fungi. The delay in the effect could be attributed to the high polysaccharide content of the biostimulant.
The high polysaccharide content of the product may have an adsorption effect on soil microorganisms, thereby reducing the beneficial effects of the biostimulant. Amino acids are known to increase the abundance of active microbial communities. They are used as alternative nitrogen. They are also used in the synthesis of protein.
Biostimulants can also reduce the adverse effects of salinity. The biostimulant contains 25% of organic matter and 2% of total nitrogen. The biostimulant is ready for use after dilution. Biostimulants have been found to promote plant growth, increase root and shoot weight, improve nutrient uptake, and stimulate natural ecological processes. Microbial biostimulants also counter drought stress and improve soil water retention.
Tolerance to abiotic stress
Enhanced abiotic stress tolerance has been demonstrated for many environmental stresses including heavy metals, salts, temperature, and pH. It is therefore important to know the physiological and molecular mechanisms of plant abiotic stress tolerance. The present study used RNA-seq transcriptomic data to identify multiple abiotic stress responsive genes (MASTs) and their respective promoters. A total of 189 differentially expressed genes (DEGs) were identified, which included 11 candidate genes (CGs) that encode for characterized proteins.
Among the 189 DEGs, five MQTLs (multiple QTLs) were identified that provided tolerance for all six abiotic stresses. In addition, a total of 23 MQTLs provided tolerance for at least one abiotic stress. These MQTLs were characterized, and their functional characteristics were compared with known genes. The remaining MQTLs provided tolerance to one to four abiotic stresses.
Among the MQTLs, the highest density of markers was found in sub-genome B. This sub-genome contains the smallest density of QTLs. A consensus genomic region was identified using GWAS. This map was found to be better than previously published consensus maps. This map contained a total of 100,614 markers. These markers were distributed across 6647 cM.
The promoter regions of the 11 DEGs were characterized, and their cis-regulatory elements (CREs) were identified. A total of 359 CREs were categorized into three functional categories, which include phytohormone responsiveness CREs, growth and development CREs and stress responsiveness CREs. These CREs were located 1.5 kb upstream of each DEG’s promoter.
In addition, a total of 539 non-redundant gene models were identified in the MQTL regions. A total of 136 physically anchored MQTLs were verified by genome-wide association studies (GWAS).
Among the 539 non-redundant gene models, a total of 21 MQTLs were found to be involved in providing tolerance to multiple abiotic stresses. Of these MQTLs, 21 had co-localized with 34 genes that are known to play a role in plant abiotic stress tolerance. This finding suggests that the MQTLs are a valuable resource for breeding for climate resilience.
The study suggests that the future of crop breeding should focus on developing transgenic plants with enhanced tolerance to multiple stresses. The future research program should also focus on developing plants with enhanced tolerance to natural environmental conditions.
Enhance growth of beneficial microorganisms
Increasing the growth of beneficial microorganisms in plant production has a number of advantages. Microbes enhance plant growth by modifying the plant morphogenesis, growth, and nutrition. Microbes release organic acids and phytohormones and promote plant development. Moreover, microbes have the ability to induce defense responses in plants. Plants also sense and respond to rhizosphere-inhabiting populations, and these signals are key to plant growth.
Microbes can enhance plant nutrition by promoting the uptake of specific nutrients. For instance, microbes can increase the uptake of sulfate by increasing the uptake of the sulfate transporter LePT4. These microbes are known to be capable of mineralizing sulfonates, which fungi are not capable of doing. Microbes also release VOCs that enhance plant growth and resistance to stress.
Microbes have also been identified as promoting salt tolerance in plants. In addition, a growing number of microbial VOCs have been shown to enhance plant growth and resistance to stress. These VOCs can be a source of bioactive compounds and can be useful in agriculture.
The interactions between microbes and plants are complex. There are a number of cellular and molecular mechanisms underlying these interactions. Understanding the mechanisms underlying beneficial plant-microbe interactions is essential for developing strategies to enhance crop production under abiotic stress conditions. In addition to enhancing the uptake of specific nutrients, microbes also act as antimicrobials to control plant diseases. They can also compete with pathogens for sites of interaction, and directly attach themselves to pathogen cells. Moreover, they may exert antagonism by producing antimicrobial compounds.
Beneficial microorganisms can also increase plant phosphorus uptake. A study on phosphorus acquisition has shown that bacteria and fungi can increase phosphorus uptake by up to two-fold. This uptake is mediated through the Pht1 family of plant phosphate transporters, which are expressed at the root-soil interface.
Plants respond to rhizosphere-inhabiting bacteria and fungi by producing signaling molecules. The following are some of these signaling molecules: VOCs, cytokinins, cyclic antimicrobial peptides (AMPs), AHLs, and phytohormones. Increasing plant nutrient uptake will enhance plant growth and yield.
Understanding beneficial plant-microbe interactions is an essential prerequisite for developing a sustainable agriculture strategy in response to climate change. A holistic approach incorporating multiple biotic and abiotic stress factors will increase yields and ensure food security.
Increased water uptake and nutrient utilization
Various types of plant biostimulants have been applied to increase water uptake and nutrient utilization in plant production. Biostimulants increase microbial activity, which improves nutrient uptake and increases soil properties. In turn, they increase the number and efficiency of plant growth factors. Biostimulants may also be used to mitigate stress, such as water deficit, salt stress, or toxic aluminum.
Biostimulants can be either synthetic or natural. They may contain humic acids, vitamins, amino acids, or other organic compounds. Biostimulants are also composed of precursors of plant hormones. Some may be classified as biopesticides or biofertilizers, and others could fall under the jurisdiction of the EPA or USDA.
Biostimulants may be applied as a single molecule or as a mixture. They are also used as an ingredient in crop protection products. Various types of biostimulants have been identified, including mutualistic endosymbionts, fungal endophytes, and bacteria. Biostimulants are also used in conventional productions, as well as horticultural crops.
Biostimulants are considered beneficial because they act directly on physiological processes in crops. They can be applied to promote root growth, reduce salinity stress, improve nutrient uptake, enhance germination, and increase crop quality. They may also improve soil properties and increase crop productivity.
Agricultural use of biostimulants will require temporally adapted solutions. To increase their effectiveness, these products must be screened for their effects in the field. In addition, stewardship plans and monitoring tools must be developed. This should also include consideration of ecosystem services.
The development of new biostimulants will need to include chemical interactions between the materials. Many of these interactions are strain-specific, and thus require careful screening and research. In addition, biostimulants must be tested for their long-term effects. This should be considered in developing decisions about plant biostimulants.
Several types of plant biostimulants have been identified, and the industry and regulators are working towards an agreed-upon definition. A common approach to developing biostimulants is to develop a list of promising candidates using a stepwise procedure. The process begins with field observations, followed by screening of candidate microorganisms under controlled conditions. This method may lead to the development of sui generis approaches that could optimize data bridging with existing regulations.
