Acidic compost tea enhances phosphorus availability and cotton yield in calcareous soils by decreasing soil pH
Article Summary By: Maya Shydlowski
In a fresh study published out of the Shihezi University College of Agriculture in China, researchers tested the effects of compost tea on cotton crops in calcareous soils. Calcareous soils contain high levels of calcium carbonate, which limits the utilization of phosphorus in soil. In these soils, phosphorus accumulates but is unable to be used because it is made immobile, or unavailable. Phosphorus then becomes a limiting factor in crop growth, a problem agriculture has been facing and trying to solve for decades. It is known that the pH of the soil effects the availability and uptake of various nutrients in the soil, including phosphorus. Lower pH indicates a greater acidity in the soil. The acidity helps to increase the mineralization of phosphorus. Mineralization is the process by which organic phosphorus is turned into forms easily accessible and taken up by plants. Calcium carbonate in calcareous soils raises the pH, which is why its presence in soil limits phosphorus uptake. Compost tea is generally acidic due to its components and fermentation process. Therefore, compost tea has the potential to decrease the pH of the soil and increase the mineralization and uptake of phosphorus.
In this study, the researchers tested just that: They attempted to amend the effects of calcareous soils by applying compost tea. Multiple plots were set up with different management treatments to test this. One pot had an organic fertilizer, another had compost tea, another contained phosphoric acid, and another was an unfertilized control pot. Each had different pH levels, with the lowest being the phosphoric acid, followed by the compost tea, organic fertilizer, and control. These treatments were applied to potted cotton plants and fertilized over multiple months. The researchers took soil samples regularly and analyzed the plants post-harvest. They recorded the amount of phosphorus found in available, moderately available, and unavailable forms.
The results showed that the treatment types had significant effects on the phosphorus content of the soil and the crops. Applying organic fertilizer, compost tea, or phosphoric acid decreased the pH of the soil. Because of this, these amendments also changed the composition of the forms of phosphorus in the soil. Both the phosphoric acid and compost tea treatments had higher levels of mobile, available phosphorus. The experiment also showed that the treatments affected the growth and yield of the cotton plants grown. Compost tea significantly increased the plant height and leaf number compared to the control treatment. The compost tea treatment had the highest cotton yield, followed by the phosphoric acid treatment, organic fertilizer, and then control. The phosphorus concentrations in the plants were significantly higher in the compost tea and phosphoric acid treatments, which corresponds to the yield findings.
Overall, this study found that the acidity of the soil amendments made the greatest difference in phosphorus availability and uptake. These results show that using acidic compost tea as a fertilizer in calcareous soils can increase phosphorus uptake, improving crop growth and yield. This has positive implications for agriculture in the future. Hopefully growers will turn to compost tea as a viable amendment to better their soils and their crops.
Compost Tea Induces Growth and Resistance against Rhizoctonia solani and Phytophthora capsica in Pepper
Need a reason to be more amazed with compost tea? Faculty at the University of Salamanca in Spain have been studying the effects of compost tea on pepper crops, especially their resistance to Rhizoctonia solani and Phytophthora capsica, pathogens common in pepper crops. Ten different treatments were set up to test how various factors in combination with the compost tea affected the pepper plants’ growth and pathogenic responses. The compost tea solution that this team worked with was based off composted green waste, which is basically recycled remnants of yard trimmings and other organic sources. They analyzed multiple samples of the compost tea for its nutritional and microbial composition, as well as some other chemical properties.
The researchers first performed in vitro assays, which are tests that specifically target disease and are done on isolated systems. This is helpful in identifying factors and their effects on specific characteristics. The researchers also performed in vivo assays, which are tests on entire plant systems. This is more beneficial in discovering real-world implications. The researchers grew one set of pepper plants with no compost tea or pathogen introduction and another set of plants with compost tea but no pathogen introduction. They also grew plants with and without compost tea and with each pathogen introduced after transplanting. Their set up would allow them to observe how the compost tea affects plants diseased with these pathogens.
At the end of the experiment, the researchers concluded that the compost tea successfully reduced pathogenic growth and increased plant growth, even when pathogens were introduced to the system at different times. Based on their analysis of the composition of their compost tea and based on others’ research, they decided that the compost tea most likely improves these characteristics because of the nutritional value and microbial makeup of the compost tea. Their solution contained multiple microbes known to help plants fight off these pathogens. Additionally, nutrients measured in the solution, especially nitrogen and potassium, were sources of fertilization for the growth and resistance of the crops. Their in vitro assays showed similar results of pathogen growth in the presence of the compost tea, and therefore the microbes that exist within it.
Overall, this experiment shows the potential for compost tea in pathogen resistance as well as plant growth and yield. It highlights the importance of microbial activity in plant life and in agricultural systems. The researchers did say that their compost tea was not a complete source of nutrients for the peppers, so it would be interesting to see how additional fertilizer sources would impact these findings. Just another reason to research organic systems and to use compost tea!
R&D Piece Authored by: Maya Shydlowski
fAntifungal Effect of Volatile Organic Compounds from Bacillus velezensis CT32 against Verticillium dahliae and Fusarium oxysporum
Here's a doozy. A group of scientists in China wanted to look into whether or not microbes in compost tea have the ability to ward off disease-causing fungi by producing volatile, anti-fungal compounds.
Volatile Organic Compounds (VOCs) are substances that freely dissipate into the environment. You have probably heard about low-VOC paints, which are paints that do not release toxic fumes, sparing the brain cells of many hardworking painters. In this experiment, the scientists were looking for bacteria that were good at producing VOCs in order to stave off the growth of phytopathogenic fungi.
The researchers first made compost from corn stave (which is the remainder of the corn crop after the cobs and the kernels have been harvested) and cow manure. They used 1 part manure to 5 parts stave. This was turned every seven days for five weeks. Then this compost was used to make an aerated tea. A sample from the tea was taken, and then diluted and plated onto petri dishes so that individual colonies of bacteria could be isolated. The individual colonies were then identified using PCR, and assayed for biofungicidal VOC action. This was done by growing the isolated microbes alongside pathogenic fungi. The bacteria and fungi were separated so that the only thing they shared was air. The growth, or lack thereof, of the pathogenic fungi was used to determine if the bacteria was producing an inhibitory VOC. The scientists then selected the most effective VOC producing microbe, which turned out to be the one and only, Bacillus velezensis strain CT32.
Once the researchers had their VOC star-microbe, they looked further at the VOCs being produced. They found that the bacteria was making 30 unique VOCs, 6 of which had never been seen in bacteria or fungi before. Then the scientists went even further, separating out each VOC and testing them individually for the inhibitory action against fungi. Eight of the thirty compounds proved to have anti-fungal properties. The scientists propose that this microbe, and others like it, could be used as biofumigants in order to help prevent vascular wilt infections from pathogenic fungi.
There was a lot of science done in this experiment. The researchers kept looking further and further and finally were able to make a definitive statement about what is happening with our teas and why they work the magic that they do. Thank you very much to the researchers in China for furthering our understanding of this amazing microbial world.
Markedly different gene expression in wheat grown with organic or inorganic fertilizer
This paper is a little old in science years, but extremely important nevertheless. A group of Ag-Researchers in the farming town of Rothamsted in southeast England looked at the genetic expression of organically vs. synthetically grown wheat grown in 2002, 2003, and 2004, The synthetic fields were fed with Ammonium Nitrate, while the organic fields were fed with Farm Yard Manure.
The experiment was relatively simple, however used relatively high-tech genetic profiling machinery. After harvest, genetic expression was assessed in wheat grains from the different fertilizer types. Analysis was done using Polymerase Chain Reaction (PCR) to assess and quantify the RNA found in the grains. The RNA, which is made from codes of DNA, was compared to wheat's known DNA library. The presence of RNA indicates which genes in the DNA had been turned on in order to make the RNA. An elegantly simple example of real world metabolomics, the study of the economy of metabolism.
The scientists found that the number of genes transcribed was drastically higher in the Organically grown wheat than in the Ammonium Nitrate grown wheat. Organic wheat had both a higher diversity of genes activated, and a much higher level of expression. The majority of genes identified were expressed some 4-5 times more than their synthetic counterparts.
This study shows that there is a significant 0difference in how a plant expresses its DNA in response to it's environment (this is an epigenetic changed based on nutritional environment) The increase in genetic expression has direct correlation to the levels of leftover organic molecules found in plant material. The next step to take with this research is to determine what this diverse chemical signature does to plant growth and subsequently the quality of the final produce. Basically, does more and diverse genetic expression lead to better food and medicine? The current science does seem to support this.
So, the next time some tells you that there is no difference between organic and synthetically grown food, you can confidently say otherwise. The reason why those organic strawberries taste better may have to do with the fact that they are utilizing much more of their genome to grow. Thanks science!!!
Integration of Some Bio Compounds with Compost Tea to Produce Sweet Corn without Mineral Fertilizers
Leave it up to ag-scientists living in a dry, resource limited area to come up with the next newest agriculture solution. A group of researchers wanted to see if they could grow corn at a rate considered successful without using synthetic fertilizers, and instead using a nutrient-fortified compost tea.
Compost tea alone carries very little of the macronutrients required for robust plant growth, so the scientists combined the actively aerated compost tea with one of 3 nutrient sources. The nutrient sources they used were: algae extract, azolla (duckweed), or yeast extract. The tea was brewed for 24 hours, then one of the three additives was mixed in. Then the mixtures were applied to plots of sweet corn.
There were 5 total plots, one that was fed with a conventional synthetic NPK fertilizer, one with only compost tea, and then three mixtures of tea and additives. The corn was allowed to grow through the season, with growth and yield parameter surveyed at the end of the cycle. This experiment was repeated in two successive years in order to attain substantive data.
After the second year's trial the data was analyzed to see if there were any differences between the conventional (synthetic) corn and the compost tea grown corn.
Amazingly, the compost tea plus yeast extract plot was found to yield equally to the conventionally grown corn. The dry weight, size, and yield all were statistically no different, showing that tremendous results can be achieved using natural methods. The other tea/additive plots produced 10-20% less corn as compared to the tea/yeast or conventional group.
These findings indicate that the relatively simple to produce yeast-extract has the potential to replace costly, and potentially toxic conventional NPK fertilizers, while at the same time contributing to good soil health by using a sustainable approach. The amount of tea and additive used in the experiment was very small in comparison to the amount of NPK fertilizers applied to the field. The costs, both financially and environmentally, are drastically less when using ecologically sound production principles.
Thanks to the Egyptian scientists Saad Abou-El-Hasssan, and Heba El-Batran, without the ardent efforts of people like this, our production systems would continue to be stuck using newly-ancient technology, and our food and ecological systems would fall further in peril. So, add some yeast to your brew and thank a scientist!!!!
Compost Tea Reduces the Susceptibility of Pinus radiata to Fusarium circinatum in Nursery Production
Pine trees used for reforestation are grown from seed or tissue culture, taking some 9 months to mature to be transplant-ready. During this period, cultural conditions can increase susceptibility to fungal pathogens. A group of Spanish researchers wanted to see if compost tea provided any protection against these pathogens, specifically the species of Fusarium that causes Pitch Canker. .
The scientists looked at several aspects of compost tea and it's affect on the growth and physiology of pine seedlings.
The first experiment involved making perti dishes that had compost tea added to them after they cooled so the microbes in the tea were not sterilized by the heat. The scientists then placed a small colony of Fusarium in the center of the dish and watched to see if the colony grew. Not surprisingly (if you have been reading previous blog posts) the dishes treated with compost tea showed a great inhibitory effect. As compared to a control plate (where there was 0% inhibition), tea reduced growth up to 45%. Meaning, that the Fusarium colony grew at about half the rate of the un-treated plate. It was also observed that there was 79% less germination of the fungal spores, thereby reducing the potential for growth even further. This promising data pushed the scientists to research further.
Next they wanted to see how tea acted in a real-life situation (petri dish experiments are referred to as in virto whereas "real-life" is in vivo). Pine seedlings were watered with compost tea monthly, and also inoculated with Fusarium spores. The researchers monitored disease severity over a nine month period. And, not surprisingly, again, the plants treated with tea had significantly less internal and external disease symptoms. Furthermore, the tea-treated plants had higher amounts of internal defense compounds, indicating that compost tea helps to bolster a plant's immune system.
This study actually had a lot more information than described here, all of it pointed to tea being extremely beneficial as a fungal pathogen preventor. Thanks to the Spanish scientists with arboreal interests for furthering our understanding of compost tea and it's many benefits. Muchas gracias amigos intelligentes!!!!
Ecological nutrient solutions on yield and quality of melon fruits
Want tastier melons? Who doesn't!?!? Agricultural Scientists in Mexico wanted to see if using natural growing techniques could produce melons equal to or better than melons grown using synthetic fertilizers.
To do this experiment, 4 different treatments were applied to melon plants growing in a greenhouse. The treatments were: Compost Tea, Vermicompost Tea, Vermicompost Leachate, and Synthetic Nutrient Solution. The melon were treated weekly and at the end of the season, the harvests were weighed and assayed. Yields, Brix, phenolic content, antioxidant content, and soluble solids were all determined in the laboratory.
The scientists found that the yields were all similar, however the nutritional benefits of the natural growing solutions were significantly greater. Higher soluble solid content in the compost tea treatment indicates that the fruits contained more "stuff" and less water. Part of that "stuff" is measured in Brix, which is another word for sugar content. The compost tea had the highest Brix reading of the soluble solids. This translates into sweeter fruits. Combined with the greater antioxidant capacity, it's clear that melons grown with natural methods are tastier and healthier. !!!Muchas gracias a los cientificos por la informacion azuca!!!
Compost Tea Induced Callus Proliferation and Defense Response in Rice (Oryza sativaL.) Callus Cells
International Journal of Current Microbiology and Applied Sciences, 2019
Fresh tea knowledge coming out of India! Scientists worldwide are recognizing that compost tea does have some extremely beneficial attributes. Tea has been shown to undoubtedly increase growth and fight off pests and disease. Now that tea's efficacy has been settled, inquisitive scientists are starting to ask the whys and hows.
A group of scientists from the Department of Plant Biotechnology at the University of Applied Sciences in Bangalore India wanted to see if compost tea stimulated known plant-defense chemicals. They took undifferentiated plant cells, known as callus cells, and put them on a petri dish that had been treated with compost tea. The cells were allow to grow for 15 days. The scientists then looked at the plant cells and determined if, and how much of, the plant defense chemicals were present. (That was a very simplified version of the whats and hows, click the Link Here button above if you want to know the nitty-gritty).
And low and behold, the scientists found that the cells treated with compost teas produced more internal plant defense compounds (peroxidase and superoxide dismutase, if you were wondering). Also, the callus cells grew bigger, ending up with a significantly higher dry weight than the non-tea-treated control. Interestingly, some of the callus cells that had been exposed to tea initiated root development. This lead us to think that something in compost tea is analogous to rooting hormones. Further investigation is warranted.
Science shows us again that what the old timers have been saying for years, compost tea makes plants stronger and bigger. Tell us your tea-tales in the comment below!
Different carbonic supplements induced changes of microflora in two types of compost teas and biocontrol efficiency against Pythium aphanidermatum
Sugars are known to be microbial food sources and have long been used in farming as a supplement to promote plant growth. In compost tea, Molasses is the most often used sugar source and in known to produce a beneficial, biologically active tea. However, there is a not so sweet side to this story when it comes to disease prevention.
Scientists at the Ningxia Normal University in Guyuan, China wanted to look at how compost teas brewed with different microbial food sources (Glucose, Sucrose, Starch, Chitin, Cellulose, & Wheat Straw) would affect damping off of cucumber seedlings caused by Pythium. The scientists used two different types of compost (soy straw/cattle manure, and wheat-straw/chicken manure), and brewed teas 7 teas each (made with the six listed food sources, and one tea as a control with no food source). Then the teas were assessed for: physio-chemical properties, enzyme activity, microbial populations and colony types, in vitro (in the lab) and in vivo (in field) disease suppressive qualities.
What was found.... there is a significant amount of diversity in the teas and their respective attributes. From pH, to Water Soluble Carbon, to enzyme activity, to microbial populations, the two compost types and their food sources produces a variety of results, which indicate the complexity of these dynamic concoctions. The most stand out piece of information is that in the greenhouse studies, the teas brewed with Glucose, Sucrose, and Starch were associated with higher incidence rates of damping off. The Chitin, Cellulose, and Wheat Straw teas showed significantly lower rates of the disease. This leads us to believe that compost teas produced with sugars are less effective in controlling the fungal pathogen.
At TeaLAB, we generally use Fish Powder as a food source for our teas, and only recommend molasses (sugars) to be used in the last weeks of the growing season. This direction has been based on our own experience, a healthy understanding of the soil food web, and information learned from the farmers and gardeners that share their experiences with us. It is very good to see that there are scientists on the other side of the globe working to better our understanding of the brew, so that we can then make you more successful in your gardening endeavors. Thanks to the researchers, and to you too!
Impact of Compost Tea in Controlling Chocolate Leaf Spot Disease and Soil Microorganisms' Density in Faba Bean (Vicia faba l.)
Egyptian Journal of Desert Research
Living in a desert presents several challenges for agriculture. It's not just the lack of water, but also soils that are low in organic matter, microbial life, and nutrition. The poor growing conditions can lead to weak plants that are susceptible to disease. A research team in Cairo wanted to see how compost tea might help the situation.
The farming scientists tested several aspects of tea: They grew disease causing fungi in petri dishes that contained different concentrations of compost tea to see if tea inhibited growth. They also applied tea as a foliar, soil drench, and seed soak to Faba bean plants that were infected with Chocolate Leaf Spot Disease to see if tea reduced disease severity. They looked at growth characteristics of faba bean plants, including dry weight and yield affected by the application of compost tea. They looked at the amount of defense chemicals produced by plants that were administered tea. And they looked at how tea affected the number of microorganisms in the soil.
The scholarly gardeners found some very promising results: The Chocolate Spot fungi was inhibited from growing on petri dishes that were treated with compost tea. Foliar spraying tea decreased disease severity by 60%, while soil drenching gave a 50% reduction. Compost tea helped increase almost all measured growth parameters. Soil drenching increased the number of seed pods by 127%, with only a 25% compost tea solution. Soil Drenching caused the weight and number of seeds to increase, this increase led to more than a doubling of the end yield. Microbial life in soil increased by up to 10x as compared to the control. Lastly, the amount of beneficial plant defense promoting chemicals increased in all treatments (by up to 1000%!!!). These internal plant compounds help plants fight off disease naturally.
The researchers conclude that Compost Tea could be "suggested as an eco-friendly strategy that could control leaf spot disease". This is yet another study that points to compost tea's ability to help us grow abundant crops while lowering our reliance on synthetic pesticides and fertilizers. To the scientists putting in the time to do these studies, alf šukr!!! (A thousand thanks in Egyptian Arabic).
Antifungal effects of compost tea microorganisms on tomato pathogens
Canadian researchers wanted to know if compost tea had any effect on the disease causing fungi, Botrytis and Alternaria. The fungal pathogens are known pests on tomato farms and cause a significant amount of loss to the high dollar crop.
To test tea's effects on tomatoes, the scientists brewed up a compost tea that was derived from sheep manure compost. They used a series of laboratory techniques to isolate individual species of microbes in the tea. Then they grew those individual species on petri dishes that also had Botrytis and Alternaria fungal spores growing on them. The scientists looked for the petri dishes of bacteria that inhibited the growth of the fungal spores most effectively. They found the most anti-fungal strains were Bacillus subtilis and Brevibacterium linens. The scientists then took these two beneficial bacteria and tested how they protected actual tomatoes from fungal infection.
To do this, they injected tomatoes with both the beneficial bacteria and the disease causing fungus. They did this two ways: the bacteria before the fungus, and the fungus before the bacteria. The reason for the two scenarios was because they wanted to see if there was a preventative aspect to applying the beneficial microbes prior to the introduction of the fungus. They also wanted to see if the bacteria worked better as singular isolates, or if they were more effective when they worked as a pair. The infected tomatoes were then incubated in a warm and moist environment, allowing the bacteria and fungus to do battle. The control group were tomatoes infected with fungus, but given no protective bacteria.
At the end of the incubation time the researchers measured the size of the lesions produced by the pestilent fungus. The tomatoes that were treated with the beneficial bacteria prior to fungal infection were in significantly better shape than the ones that were treated after infection. This supports the idea that an ounce of prevention is worth pounds of cure. The research also found that the tomatoes that had both strains of beneficial bacteria were well better off than the tomatoes that were inoculated with only one strain. This lead the scientists to suggest that there is a synergistic effect between the two microbes that act together to suppress fungal growth. This support's TeaLAB's hypothesis that a bio-diverse compost tea is the most beneficial to the garden. The take away message is that compost tea helps reduce disease. It's a low cost, environmentally friendly way to keep a happy garden. Thanks Canadian scientists!
Utilization of compost tea for biochemical response assessment
associated with resistance to phytopathogen causing leaf spot
in Melicope ptelefoli
Malaysia's warm temperatures and wet climate create almost greenhouse like conditions that can be great for growing plants, but also great for culturing plant-disease causing fungi. Researchers from Malaysia's University of Technology wanted to determine what affect compost tea had on the growth of the leaf spot causing Grammothele lineata. The test plant was the Asian herb Melicope ptelefolia which is known for it's edible and medicinal qualities.
Researchers used two types of teas in the experiment, both were aerated, one of which was supplemented with Molasses. The researchers then made several concentrations of the tea and dipped leaf leaves into it. The leaves were then sprayed with a solution that contained the Grammothele spores. The infected leaves were incubated for a week and then the severity of infection was documented. The leaves were also tested for the amount of naturally occurring plant defense chemicals present in their tissue.
What they found was that both teas (with and without molasses) inhibited the growth of the fungal disease by up to 78%. The highest concentration (40% tea by volume) of molasses brewed tea was the most effective. The control leaf, which was sprayed with spores only, was completely infected. Moreover, the leaves that had tea applied to them produced more natural plant defense chemicals (Peroxidase and Polyphenol Oxidase). The tea boosted the plants own ability to fight off disease. This is an impressive new discovery in the compost tea realm, as most literature points to compost tea helping reduce infection through competitive exclusion. This is yet another reason to start using compost tea in your gardens and on your landscape. Thanks Malaysian scientists for furthering our understanding of why this living fertilizer is such a beneficial substance.
Evaluate the effect of compost tea and some chelated micronutrients forms on black cumin productivity
SN Applied Sciences
The Desert Research Station in Baluza, Egypt had a busy 2018 investigating the efficacy of compost tea on their sandy soils. Research scientists wanted to know what effect compost tea in combination with the chelating agents EDTA and Humic Acid had on the growth of Cumin, a plant valuable as a food and medicine.
Chlelators are molecules that hold onto biologically essential micronutrients in such a way that the micronutrients are kept available for plant use. EDTA is a synthetic, slowly to biodegrade chemical that has been shown to have toxic effects on animals, while humic acid is a natural compound that has poses no known risk to natural systems.
The scientists had 8 different treatments: Compost Tea Foliar Spray, Compost Tea Soil Drench, EDTA Foliar, EDTA & Compost Tea Foliar, EDTA & Compost Tea Drench, Humic Foliar, Humic & Compost Tea Foliar, and Humic and Compost Tea Drench. The variables that they looked at were: Plant Height, Dry Weight, Weight of Seeds, Oil Percentage, Volatile Oils, and residual Nutrient content in Plants. The 8 treatments were administered twice during the growing season, at 35 and 70 days after seedling emergence. All treatments including the control were fed a conventional fertilizer at recommended rates.
The researchers grew some pretty outstanding results. In all treatments there was an increase in all measured variables, however the highest values were seen in the Compost Tea and Humic Acid Foliar treatment. Plant height, dry weight and weight of seeds, oil percentage and volatile oils were to shown to be maximized by foliar spraying compost tea that included humic acid. The next highest values were generally seen in the Compost Tea and Humic Acid soil drench. Across the board it was clear that compost tea and humic acid are beneficial to plant growth.
The researchers conclude that compost tea combined with humic acid provides a significant boost to productivity. Humic acid is a viable, safe, and better alternative to EDTA. A big thank you to the cumin cultivating scientists of Beluza, Egypt.
Comparative bioactivity of selected seed extracts from Brazilian Annona species and an acetogenin-based commercial bioinsecticide against Trichoplusia ni and Myzus persicae
A group of researchers from Brazil and Canada collaborated on a study compare the effectiveness between seed extracts, a commercial bioinsecticide, and a pyrethrin based insecticide. The seed extracts were made from several species of Annona, also known as pawpaw or sugar apple. The bioinsecticide was acetogenin-based. Acetogenin is naturally found in Annona. Researchers wanted to determine if the seed extract was as effective as the commercial formulation, as compared to the pyrethrin based insecticide with known efficacy.
Seed extracts were made by grinding seeds for ripened fruits into a powder. The organic compounds within the powder were extracted with alcohol. The alcohol was then allowed to evaporate, leaving the extracted compounds behind. Those compounds were then applied to insects as either oral ingestion or a topical spray.
Researchers found that, or four species tested, the seed extract from Annona mucosa species was the most effective in both cabbage looper and aphid control. Researchers also found that the seed extract of A. mucosa was as effective or better than the commercial bioinsecticide and the pyrethrin based insecticides. A 98% mortality rate was observed in greenhouse trials on Cabbage Loopers that were sprayed with the A. mucosa seed extract, while the control group which was sprayed with the pyrethrin based insecticide displayed a 98.88% mortality. Aphid control showed similar results. The researchers conclude that the seed extracts are a viable option as biorational pesticides for cabbage looper and aphid control.
Compost tea spraying increases yield performance of pepper (Capsicum annuum L.) grown in greenhouse under organic farming system
Italian Journal of Agronomy
Compost Tea is making a name for itself around the world, most recently in a farm town called Eboli in the boot shaped country of Italy. Univeristy researchers wanted to see what affects aerated tea would have on pepper plants when used as a foliar spray.
Compost was made from a variety of vegetable wastes and then aerated in water. No food sources were given to the microbes. The tea was then diluted to a 10% solution, and sprayed on foliage weekly during the growth cycle. The trial was done over a two year period in order to have enough data to run meaningful statistics.
The Italian researchers found that there was a 21% increase in yield the first year, and a 16% increase in yield the second year. The yield increase was due to an increase in the number of peppers that each plant produced, and not due to a size increase in the fruits. The available nutrition and biologically active compounds produced in the aerated tea were able to increase flower sites and sustain the growth of more peppers. According to this study, Peter Piper would be wise to spray his peppers if he wants to pick more than a peck. And you would be wise to do the same. !Ciao e grazie!
Evaluation of different types of compost tea to control rose powdery mildew (Sphaerotheca pannosa var. rosae)
International Journal of Pest Management
Those Iranian scientists have done it again, showing aerated compost tea works great as a fungicide, especially at a 1:8 dilution, sprayed twice weekly. A simple experiment was set up on red roses that were infected with powder mildew. The scientists used several combinations of variables: Aerated vs. Non-Aerated tea, Compost versus Vermicompost Tea, Dilution strength 1:8 vs. 1:16, and weekly vs. biweekly sprays.
The roses were allowed to grow, and the numbers of infected leaves were counted and used to calculate damage rates. It was found that Aerated Compost Tea sprayed 2 times weekly, at a dilution rate of 1 gallon of tea to 8 gallons of water, was the most effective at suppressing the growth of powdery mildew. This research points us every closer to an exactness we can use to better our day to day gardening experience. Thanks Iranian scientists!!!
Efficiency of garden waste compost teas on tomato growth and its suppressiveness against soilborne pathogens
University of Salamanca/Faculty of Agricultural and Environmental Sciences
Compost Tea shows its many strengths once again. Researchers in the agriculturally rich country of Spain performed greenhouse trials on tomatoes with both compost and worm casting teas. The two types of teas were tested for the amount of nutrition present, their affect on fungal pathogens, and their effect on growth. The compost and worm castings were made from the same sources of green waste in order to compare equitably. Tomato were infected with Fusarium, and Rhizoctonia, two well know disease causing fungal pathogens, and the were then watered with one of four dilutions of compost tea. The plants were allowed to grow over a three month season, and then were evaluated for growth characteristics and disease severity.
The ardent scientists found that the both types of teas produced excellent results. The evaluation of the teas showed that there were significant amounts of soluble plant fertilizers present, along with several beneficial plant hormones like the ever-important Indole Acetic and Salicylic acids. The severity of the diseases were drastically reduced through the use of compost teas. The vermicompost tea provided better defense against Rhizoctonia, while the compost tea fought off Fusarium most effectively. The tomatoes that received teas also grew much more. This is easily explained by increased amounts of fertilizing and growth promoting substances in the tea, as well the disease suppressing effects.
Effect of Dry Yeast and Compost Tea on Growth and Oil Content of Borago Officinalis Plant
Journal of Agriculture and Biological Sciences, 2010
Borage is a common flower whose oils contain several beneficial substances that are used in natural and modern medicine. A group of scientists in Egypt wanted to see if they could increase Borage's growth and oil content with the aid of dry yeast and compost tea.
The experiment was carried out over two years in Giza, Egypt. There were 5 groups of plants tested: (1) plants watered with compost tea, (2) plants foliar sprayed with compost tea, (3) plants foliar sprayed with a liquid solution made from dry yeast and water, (4) plants foliar sprayed with tea and also foliar sprayed with yeast, (5) plants foliar sprayed with yeast and watered with comost tea. The plants were compared to a control group that did not receive tea or yeast, though was fertilized and watered similarly.
The Egyptian scientists found that compost tea applications "significantly increased plant height (cm), fresh and dry weight of aerial parts and flowers (g/plant)". Foliar spraying yeast increased "values of fresh weight of aerial parts, number of suckers, seed weight and oil%". In both years, the scientists found that the combination of both watering in compost tea and foliar spraying yeast was the most beneficial.
Not only did the plants grow more productively, but the levels of beneficial substances like alpha-linolenic acid and campesterol significantly increased as well. This is the kind of information you take back to the herb garden and share with all your friends.
Phosphorus availability from rock phosphate: Combined effect of green waste composting and sulfur addition
Journal of Environmental Management
Phosphorus is extremely important for plant growth, yet it's use in agriculture is extremely inefficient. A conservative estimate is that 50% of applied phosphorus becomes unavailable as it binds with other elements in the soil. To help alleviate this, we can thank microbes.
To address this problem, a team of scientists from Italy and Spain added rock phosphate to greenwaste-compost piles at several levels, let the compost go through its thermophilic cycle, and then determined soluble phosphate levels.
The scientists found that soluble phosphorus levels increased with the addition of compost. The increase was most drastic in the treatments that had the lowest amount of rock phosphate added. Furthermore, the addition of rock phosphate made for more efficient use of nitrogen in the compost, retaining it so that it was not lost to the environment. Adding elemental sulfur was also shown to help increase phosphorus solubility. Take home message: add a little soft rock phosphate to your compost pile to create a phosphorus rich biofertilizer.
Effects of selected root exudate components on soil bacterial communities
Root exudates are substances that plant roots secrete into the rhizosphere, stimulating microbial activity which in turn helps to support a healthy soil system and productive garden. The exudates are composed of a mixture of compounds each with its own unique properties.
A group of scientists from New Zealand wanted to know which of the exudate-constituents affected microbial growth the most. They did this by selecting six of the most common root exudate components: sugars (a mixture of fructose, glucose, sucrose), lactic acid, maleic acid, and quinic acid. With these ingredients, five artificial exudates were concocted to make treatments: sugars, sugars+all acids, sugars+individual acids). The artificial exudates were then watered into soil over a 14 day period. After the 14 days, microbial activity was measured (microbial activity can be measured in bulk, it gives us a good idea of population size). Also, the numbers of species (or diversity) in each treatment was quantified.
The scientists found that the most effective recipe to promote microbial activity was the combination of sugars and lactic acid. The high level of microbial activity indicates that this treatment had the highest microbial populations. Interestingly, the sugar/lactic acid brew had the lowest diversity. The most diversity was seen in the sugar/maleic acid brew. Even more interestingly...the sugar/maleic acid had the lowest amount of microbial activity. The scientists suppose that the sugar/lactic acid brew enabled the most efficient group of microbes to quickly proliferate, while the sugar/maleic acid caused slower growth which allowed a diversity of bacteria to grow. The combination of sugars and quinic acid, as well as the combination of sugars and all of the acids produced relatively high microbial activity as well as species diversity. Take home message, use a diverse food source for your teas, and you will have a diverse and abundant microbial community. Thanks Kiwis!
The Effects of Rate and Method of Aerated Compost Tea Application on Yield and Yield component of Tomato (Lycopersicon esculentum Mill.) at Burusa, South Western Ethiopia.
International Journal of Multidisciplinary and Current Research
A group of scientists in Ethiopia wanted to see whether or not compost tea would help improve tomato production. Local farmers are trying to avoid using chemical fertilizers due to economic and environmental costs. Compost tea is a low cost alternative worth investigating.
The scientists and farmers worked together, potting up Roma tomatoes into several groups that each received a different amount of compost tea. The first group received none, and the other four were watered or foliar sprayed weekly with 300, 600, 900, and 1200mililiters of tea. The plants received standard care otherwise.
Several parameters were studied during the experiment, including: plant height, number of primary branches, root length, days to flower initiation, days to first harvest, number of fruit per plant, fruit weight, fruit size, and fruit quality.
It was shown that across the board, compost tea was significantly beneficial. Compost tea helped to grow bigger plants that produced more, larger, higher quality fruit, that were able to be harvested sooner. The total marketable yield of tomatoes was 0.6kg per plant for the control group, and 2.4kg/plant in the high application rate group. That is a four-fold increase in tomatoes to market. That kind of increase in production could lead to improving the lives of thousands of people. Thanks compost tea! (the Materials and Methods section in this paper is worth the read, click the Link Here to learn more)
Properties of vermicompost aqueous extracts
prepared under different conditions
Journal of Environmental Technology
Have you ever wondered why aerating your tea makes all the difference? Well a group of scientists from the Czech University of Life Sciences did. They too their wonder and turned it into a science experiment.
The curious life scientists wanted to see the difference in plant available nutrients in aerated vs. non-aerated teas. To do this, they tested two different vermicomposts, one made with grape pomice, the other horse manure. The composts were placed in buckets and were either aerated or just stirred. The scientists then sampled the brew every 6 hours and tested the tea for: pH, EC, N, P, K Ca, Mg, and a couple of other parameters. They then used statistics to compare the numbers. Their findings were remarkable.
All macronutrient levels increased in the aerated teas. Available nitrates levels more than quadrupled. Phosphorus and Calcium increased by one third. Potassium and Magnesium doubled. Interestingly, the majority of the nutrients were made available in the first 6 hours, having reached their maximum at 48 hours.
The reasons for these nutrients becoming available is attributed to oxidation reactions occurring in the aerated water, as well as microbial forces acting on the compost material. This study helps us to identify yet another source of compost tea's goodness. Thanks science!!!
Metabolomics for organic food authentication: Results from a long-term field study in carrots
A groundbreaking study done by a group of international scientists working out of Belgium has shown that organic produce is identifiable through DNA testing. An area of study called Metabolomics has made this possible.
Metabolomics studies the chemical fingerprints left by specific cellular processes. By looking at what chemicals are left in a cell, scientists are able to determine what has occurred in that cell. Because plants utilize different metabolic pathways depending on their growth conditions, scientists can look for specific metabolites that indicate organic or synthetic fertilizer sources. The actual process involves identifying and quantifying specific mRNA and proteins, then running that information through statistical analysis to determine if the fertilizer source.
In this study on carrots, if researchers knew the harvest year, they were able to identify with 100% accuracy whether or not the root vegetables were of organic origin. If they did not know the harvest year, the success rate was 70-100%.
This study will help to ensure there is no counterfeit produce in the organic section at the market. More importantly, it shows that organic produce is technically different than synthetically grown produce. The residual metabolites found in organic produce could be valuable compounds leading to greater health in those that consume them. This study has many implications, we look forward to learning about all of them.