HOW GROWING WITH ACTIVE SUGARS HELPS REDUCE THE AMOUNT OF NPK SALTS

Enhancing Plant Growth Naturally While Minimizing Fertilizer Dependency

ABSTRACT


Sugars play an important role in plant growth and development. They are involved in signaling, gene expression and defense systems. Sugars are produced by the plant through photosynthesis. As sugars are made, they are stored as starch or used to synthesize lipids and proteins. Applying exogenous sugar sources to crops has shown to increase leaf area size and fight off harmful insects. Traditionally, farmers have used heavy fertilizers for plant food. This has had detrimental impacts on our environment. Peak Roots is suggesting a change for traditional horticulture: to grow with active sugar-based nutrients, in combination with a light NPK soil. Light soils provide plants with the trace nutrients needed to sustain life without having to add additional nitrogen, phosphorus or potassium. Growing with an active sugar-based feeding regimen also reduces environmental impact of heavy minerals and creates a more simplified growing process.


Keywords: Photosynthesis, xylem, phloem, active sugar, sugar signaling, gene expression, carbohydrate, salt, mineral toxicity, soil, chemical fertilizer, insecticide.


INTRODUCTION


Soil salinity is one of the most detrimental threats to our environment. Water systems, aquatic populations and arable land are all affected by excess salt accumulation from agriculture. To try and resolve this problem, it has been suggested to grow with active sugar-based feeding regimens versus heavy salts. A plant’s dry weight is comprised of 96.6% organic molecules that make up the components of sugar: carbon, hydrogen and oxygen. The remaining 3.4% is comprised of inorganic substances such as minerals (salts). Glucose is the most abundant sugar in the world and is synthesized by plants through photosynthesis. In plants, sugars play an important role in gene expression, signaling, growth, development and defense systems.


The traditional way of farming includes growing with fertilizers high in nitrogen, phosphorus and potassium. While these minerals are essential for plant physiology, they can easily accumulate to toxic levels in soil and crops. Only in extreme and rare cases do carbon, hydrogen and oxygen reach toxicity. Shifting towards growing with a proper balance of sugars to salts is key. The goal is to grow with active sugar sources that create aerobic environments, in an effort to prevent disease and pathogens.


As we work towards feeding a quickly growing population and sustaining agricultural lands, there has to be a drastic change in the way we farm. The first step is attempting to balance out the mistakes we’ve made throughout history by growing primarily with sugars and a small percentage of salts (96.6% sugars and 3.4% salts).


PLANT ANATOMY


Plants obtain their nutrients from both above and below ground. Water and minerals are absorbed from the soil, while light and CO2 are obtained from above the ground’s surface. Water, minerals and other nutrients are transported throughout the plant in either the root system or the shoot system. Root systems are generally not photosynthetic. They uptake nutrients from the soil to send to the shoot system, which is comprised of the stems and leaves. The shoot and root systems work symbiotically and depend on each other to supply the entire plant with nutrients, flowing in both directions (Reece et al., 2011).


Roots are organs that anchor vascular plants to the soil to absorb minerals and water. In addition, roots have the ability to store carbohydrates (sugars). Taproots develop from an embryonic root and grow deep into the soil. In addition, taproots give rise to lateral roots, which branch in an outward direction. At the tip of each root are microscopic hairs that increase surface area, allowing for more nutrient and water absorption. A cloud like formation of sugars exists around the root tip and hairs. These sugars, in addition to water and minerals, continually assist in feeding the plant. Absorption of water and nutrients can be inhibited when soil nitrate levels are too high, causing root bound to occur (Reece et al., 2011).


Stems separate leaves, which are the main photosynthetic organs of the plant. Stems consist of alternating node systems and promote nutrient transport throughout the plant. There are two main vascular systems that carry out long distant nutrient transport: the xylem and phloem. The xylem carries dissolved minerals and water from the roots into the shoot system. The phloem primarily transports sugars to where they are needed, typically downward, in the direction of the roots (Reece et al., 2011).


Figure 1: Nutrient transport in plants involves the root and shoot systems. In addition, the transport of sugar flows between sources and sinks. Sources (leaves) provide the plant with water, sugar and nutrients. Sinks are areas in need of nutrients and consist of roots and other developing tissues. The root system sends nutrients upward to the shoot system, which is comprised of leaves and stems.


Figure 2: Basic leaf cell anatomy. The xylem and phloem are highlighted in red and blue. Together, the xylem and phloem carry out long distant nutrient transport in plants.


SUGARS


Sugars are organic molecules comprised of carbon, hydrogen and oxygen. They are known as carbohydrates, which translates directly to “hydrated carbon”. The most abundant sugar on Earth is glucose, which is made by plants through photosynthesis. As plants produce glucose, it can be stored in the plant as starch or used to synthesize lipids and proteins (Reece et al., 2011). Before glucose is transported throughout the plant, it is converted to sucrose, the primary carbohydrate involved in long distance transport (Julius, Leach, Tran, Mertz, & Braun 2017).


Carbohydrates can be classified as either simple or complex. Simple carbohydrates contain one to two sugar molecules. Sugars that contain one molecule are considered a monosaccharides. Sugars that contain two molecules are called disaccharides. Complex carbohydrates are broken down into oligosaccharides, which contain three to ten sugars and polysaccharides, that contain hundreds to thousands of sugar molecules (Reece et al., 2011).


Common monosaccharides include glucose, fructose, galactose and ribose. Lactose, maltose and sucrose are the three main disaccharides. Both starch and glycogen are polysaccharides and are the storage forms of glucose in plants and humans, respectively. Fiber is another polysaccharide found in plants that is comprised of long sugar chains, not easily digested by humans. Fiber provides a backbone for cell structure, supporting leaves and stems (Reece et al., 2011). Glycogen is the animal storage form of glucose and is found in liver and muscle cells. Starch is formed as a combination of amylose and amylopectin. Amylose is a long, straight chain of hundreds to thousands of glucose molecules, while amylopectin is highly branched and much harder to break down (Reece et al., 2011).


Figure 3: Common mono and disaccharides. Glucose is the most abundant sugar on earth.

Figure 4: Amylose and amylopectin are the two storage forms of starch. The branched chain of amylopectin is represented here.



SPENT VS. ACTIVE CARBON


In nature, fruits contain a perfect ratio of salts to sugars. For example, when an apple or an orange falls from a tree, it breaks down into salts and sugars. The inside component of the fruit is made up of 96.6% sugar, while the wrapper (outer layer) is composed of 3.4% salt. When the fruit falls from the tree, the organic molecules within it are active. They are a viable carbon source for the microbes and soil. These active sugars give and sustain life.


On the other hand, when a sugar is considered inactive, or spent, the bonds have been broken. The carbon, hydrogen and oxygen are not reliable sources of energy anymore. Molasses is an example of spent carbon, where the sugars have been heated and altered in various chemical processes. Another example of spent carbon is a campfire pit. As a fire burns, biomaterial that was once alive gets turned to ash. That ash, also known as biochar, contains spent carbon which will not be used to help sustain life. Even after years, nothing is able to grow in a burnt fire pit. However, if active carbon enters the soil, it can support the growth of other living organisms.


Figure 5A: A representation of fruit falling from a tree, breaking down in the soil. This fruit will naturally break down into roughly 96.6% carbon, hydrogen and oxygen and 3.4% salts. Natural decomposition in the soil produces active sugars.


PLANT COMPOSITION


Around 80-90% of a plant’s mass is made up of water (Reece et al., 2011). Inorganic substances make up about 3.4% of dry weight and the other 96.6% is made up of organic substances such as carbon, hydrogen and oxygen (2018). There are nine essential macronutrients needed for plants. Macronutrients are needed in larger amounts compared to trace minerals. They play vital roles in the plant’s development. These macronutrients are carbon, oxygen, hydrogen, nitrogen, phosphorus and sulfur. Potassium, calcium and magnesium are considered macronutrients but are needed in smaller quantities. Nitrogen plays a major role in plant crop yield, pigmentation and plant structure. It is a major component of proteins, chlorophyll and other organic molecules required for plant growth (Reece et al., 2011).


Figure 5B: The balance of life. The organic compounds carbon, hydrogen and oxygen make up 96.6% of dry weight plant matter.


Micronutrients are needed in trace amounts and they include elements such as chlorine, iron, manganese, boron, zinc, copper, nickel and molybdenum (Reece et al., 2011). Though micronutrients are essential for plants, they can easily reach toxic levels. Maintaining the nutrient composition in soil is important in preventing adverse effects.


Figure 6: The balance of life. Inorganic substances and minerals make up 3.4% of dry weight plant matter.

Figure 7: Trace nutrients that contribute to the 3.4% in smaller quantities.


RESPIRATION


Plants and humans undergo their own forms of respiration. While plants photosynthesize, humans undergo cellular respiration. These processes are opposite chemical reactions of each other, showing that plants and humans work in a symbiotic relationship.


Plants get a majority of their carbon dioxide from atmospheric sources, but a portion comes from microbes respirating CO2 in the soil. Once microbes produce CO2, it can be taken up by the plant to catalyze the process of photosynthesis (2018).


Plants have a sole purpose to create sugars and oxygen as a byproduct, which sustain life for humans and animals. In the process of photosynthesis, plants create sugars in a 1:2:1 ratio of C:H:O (Ex. Glucose C6H12O6).


Without a continual supply of well-balanced water and soil grow medium, plants are unable to undergo these physiological processes. Products of photosynthesis are carried throughout the plant to be used as plant food or stored as starch, fats or protein (2018).


Figure 8: Chemical reactions for photosynthesis and cellular respiration. Photosynthesis and cellular respiration are opposite reactions of each other.


SOIL


Soil is comprised of both organic and inorganic substances, as a combination of decomposing plant and animal matter (2018). Organic matter within the soil helps strengthen aggregates that improve the water holding capacity, aeration, growth and development. Maintaining healthy soil texture and composition is fundamental for a healthy, thriving plant environment. Keeping the soil healthy includes avoiding mineral toxicity.


Most soils are negatively charged. This allows negatively charged ions (anions) to bind to positively charged ions (cations) like calcium, magnesium, sodium and potassium. Positively charged ions within the soil are actively replaced with hydrogen ions during a process called cation exchange. Soils are typically slightly acidic, which allows this process to occur. Minerals that are negatively charged do not bind as easily to the soil and are released. These include minerals such as bicarbonate, nitrate, chloride, phosphate and sulfate. Unfortunately, during heavy rain falls or watering, negatively charged ions can get leached into waterways. Once the ions are washed out of the soil, they are unavailable to be taken up by the root system into the plant. This can lead to harmful environmental implications (Reece et al., 2011).


Growing primarily with heavy salts like nitrogen, phosphorus or potassium easily result in toxicity in the soil (NPK Sludge). NPK sludge causes root bound plants, limits water absorption and creates septic soil conditions (2018). Eventually, the salts will need to be flushed out. Though these nutrients are essential for plant growth in the right quantities, historically, farmers have been using them in extreme excess.


ENVIRONMENTAL IMPACT OF FERTILIZERS


Fertilizers are compounds that contain one or more chemical element, organic or inorganic. Most chemical fertilizers are classified by their nitrogen, phosphorus and potassium content (McKenzie 1998). The use of agricultural fertilizers can contribute to environmental pollution and greenhouse gases. Specifically, nitrogenous fertilizers contribute to one of the largest sources of greenhouse gas emissions within agriculture. In addition, nitrogen and phosphorus fertilizers are key contributors to eutrophication in both developed and developing countries (White & Brown 2010). Eutrophication occurs when large amounts of minerals enter a body of water and contribute to overgrowth the of certain plants (typically algae). This causes oxygen depletion within that body of water, perpetually damaging living environments and causing decimation of aquatic species (2018).


Around 40% of the world’s viable land for agriculture has soil acidity from aluminum and manganese, while 5% contains toxic levels of sodium, chlorine and boron (White & Brown 2010). Excessive amounts of sodium can lead to osmotic stress and plant cell death (Lastdrager, Hanson, & Smeekens 2014). When soil levels become salinized, crops can easily experience toxicity. This becomes problematic, just like when humans developed toxicity from certain nutrients (for example: iron).


Salinity is one of the most harmful stressors on the environment. It can cause reductions in arable land area, crop productivity and development. Currently, 20% of the cultivated land worldwide and 33% of irrigated agricultural lands are affected by excess salt levels. It is predicted that by the year 2050, 50% of arable lands will have an excess accumulation of salt (Shrivastava & Kumar 2015). On a smaller scale, salinity largely affects seed germination, water and nutrient uptake, protein synthesis, enzyme activity, photosynthesis, leaf area and chlorophyll content. Though plants still need small amounts of salt, excess accumulation can greatly suppress plant growth (Shrivastava & Kumar 2015).


Land and water are undoubtedly limiting resources when considering a rapidly increasing population (Reece et al., 2011). Our steadily growing population directly correlates to an increased demand for food. Agricultural land and soil need to be properly maintained in order to support mass food production. It is predicted that farmers will have to produce 40% more grain crop yield per hectare to feed the population by the year 2030 (Reece et al., 2011).


Aside from limited land and salinity issues, the earth’s temperature is predicted to continue to rise with increasing carbon dioxide levels. Plants will likely experience heat stress and a continual lack of water. Both of these stressors will lead to decreased crop yields, due to plants not being able to undergo proper carbohydrate partitioning (CP). CP is the process of synthesizing, transporting and delivering sugars from sources to sink tissues (Julius, Leach, Tran, Mertz, & Braun 2017). Understanding what affects CP, both negatively and positively, will allow for a better understanding of how to increase crop yields in a changing environment.


AEROBIC VS. ANAEROBIC


Anaerobic and aerobic microorganisms are present in all living soil. Aerobic processes occur in the presence of oxygen, while anaerobic reactions occur without oxygen.


When plants are in an aerobic state, they are more resistant to pathogens and pests. Maintaining an aerobic state in the soil reduces the need for synthetic pesticides. Anaerobic respiration is carried out by bacteria where CO2, lactic acid or alcohol is formed by breaking down glucose molecules (2018). Most plant and animal cells use aerobic respiration, while bacteria, yeasts and prokaryotic cells use anaerobic respiration (2018). Having a large population of aerobic microbes (breathing off CO2) present in the soil helps catalyze the process of photosynthesis.


Anaerobic microorganisms tend to overpopulate and feed on roots, which causes decay and root rot. In time, this is very detrimental to plants. The organisms will feed off of the plant’s viable carbon and fiber. Active sugars feed the aerobic microorganisms and biology in the soil that help maintain healthy, white roots (2018).


Figure 9: Example of healthy white roots.


SUGAR TRANSPORT, SIGNALLING AND GENE EXPRESSION


As stated earlier, the glucose formed during photosynthesis is necessary for plant growth, development and health. In addition, plants contain molecular networks that initiate biological processes. These networks rely on carbohydrates to function (Lastdrager, Hanson, & Smeekens 2014). Although plants synthesize their own sugars, supplying exogenous sources has shown to be beneficial. Carbon, hydrogen and oxygen rarely, if ever, reach toxic levels in soil or crops. Instead, these molecules get stored or transported to the soil to be utilized. They can be stored as starch or converted to lipids and proteins, later used for various functions.


Sugar levels reflect the plant’s ability to survive and maintain proper energy status. There are a multitude of genes that are controlled at the transcriptional level, based on the bioavailability of carbohydrates (Lastdrager, Hanson, & Smeekens 2014). Both light and sugar control gene expression in source and sink tissues (Rolland, Moore, & Sheen 2002). The TOR gene, target of rapamycin, promotes plant growth in response to high sugar levels. The SnRK1, plant Snf1-related kinase 1, is activated when there is sugar deprivation. The cyclin genes, CYCD2 and CYCD3, promote growth in seedlings and are activated by sugars (Lastdrager, Hanson, & Smeekens 2014). In addition, excess salt levels reduce gene expression and activity of cyclins, which will inhibit plant growth (Shrivastava & Kumar 2015). Specifically, during the floral transition of plant lives, sugar signals regulate very important processes that can result in greater biomass yields (Lastdrager, Hanson, & Smeekens 2014). Overall, the main genes expressed through sugar signaling are involved in development, stress response, photosynthesis, carbon and nitrogen metabolism (Rolland, Moore, & Sheen 2002).


EXOGENOUS SUGAR APPLICATION & LIGHT


As we now know, light and sugars are essential components in plant metabolism, development and growth. In addition, they can promote gene expression and play signaling roles. Eckstein et al., studied the effect of light and sugar Arabidopsis thaliana, a plant within the mustard family. The plants were grown in either 1% or 3% glucose or sucrose. Light delivered to the plants fell within three categories: weak light, (25 micromoles) medium light (100 micromoles) and strong light (250 micromoles). The control plant was grown without an exogenous sugar source but grown with the same light conditions (Eckstein, Zieba, & Gabrys 2012).


Sugars create substrates for the synthesis of other organic compounds. Light is an essential component to the process of photosynthesis and contributes to the plant’s ability to produce flower. Finding the perfect balance of light and nutrients is key. Overall, in this study, the addition of exogenous sugars showed an increased rate of photosynthesis. The sugars also had the ability to act as a photo-protectant, defending the plant against negative effects from too strong of light.


Results showed that all the plants grown with sugar developed better. The control plants, grown without sugar, had a fewer and smaller leaves. Plants developed differently based on the amount of light they were given. The plants grown in weak light also had fewer, smaller leaves. Plants grown in medium and strong light became fully developed and their leaves had the largest dimensions. Plants grown with the 1% sugar medium had a larger leaf area for both medium and strong light grow environments.


On the other hand, plants grown in a 3% sugar medium had increased leaf area as light intensity increased. This was seen specifically in the presence of glucose. Weak light levels inhibit growth and development and some combinations of sugar and light intensity work the best when paired. In this case, 3% glucose plants in strong light reached the highest value. These conditions had more of an effect on leaf area vs. leaf number, which goes to show that exogenous sugar acts as a source for biomass production.


This study also exhibited that the CAB gene (chlorophyll a/b binding proteins) expression increased as photosynthesis increased. The highest expression of the CAB gene was seen in strong light with 1% sucrose. There were no significant differences among the glucose grown plants. In stronger light conditions, CAB is expected to have exhibit higher activity (Eckstein, Zieba, & Gabrys 2012).


Figure 10: Results from the Eckstein et al., study. The graphs represent Arabidopsis thaliana plants grown in different light and sugar concentrations. Total leaf area was highest in 3% glucose, strong light conditions. The total number of leaves was highest in 1% sucrose, medium light conditions. The total leaf area was highest in 3% glucose, strong light conditions.


SUGAR AS AN INSECTICIDE


In addition to the other beneficial applications of sugar, it can be used as an insecticide. The use of synthetic, chemical pesticides can linger on plants and even find their way into the food supply. Spider mites and other soft bodied insects are common infestations. However, a non-toxic, natural insecticide has been discovered for fighting spider mites. Cacti from the genera Opuntia, or the prickly pear cacti, can be ground into a mulch. Next, it is mixed with a solvent such as water or alcohol and tannic acid. Both tannic acid and cacti are made up of carbon, hydrogen and oxygen (1981). Tannic acid is a key component to the insecticide solution. It is a polyphenolic compound (C76H52O46) and contributes to the color and taste of many foods and beverages (Bien 2016). Tannic acid has a glucose center and carbohydrate backbone (2018). This insecticide has also shown to be successful when treating plants with other aphids and mealybugs (1981).


The Graduate School of Western Carolina University completed a study about the effects of tannic acid as a biopesticide. Polyphenolic compounds, like tannic acid, have the ability to defend against ultraviolet radiation and pathogens. They also have a high antimicrobial and antioxidant function (Bien 2016). Tannic acid has shown to inhibit the growth of Fusarium graminearum, a fungus that can cause head blight in barley crops. Tannic acid was administered to the plants to be compared to a commercial fungicide. The tannic acid treated crops showed to be less infected compared to ones that were untreated (Bien 2016).


Studies have shown that applying sugar solutions to crops can also increase the number of beneficial insects. According to USDA-ARS Entomologists, beneficial insects were 70% higher in sugar-treated corn plots, in comparison to those that did not get a sugar treatments. After one week, sugar treated corn plots still had twice as many beneficial insects versus the corn crops that did not receive treatment. In this study, there was an 18% reduction in specific infestations and a 35% reduction in leaf area damage from harmful insects. Findings show that applying sugar to crops (in this case corn), allows for beneficial insects to over populate and harmful infestations to be reduced (2015). Furthermore, sugars promote plant defense systems. Studies have shown that the application of sugar to fungal-inoculated root systems caused an over expression of genes that allow for defense mechanisms within the plant, reducing fungus growth (2015).


BENEFITS OF GROWING WITH BIOBASED SUGARS


USDA Biobased product. Biobased products are derived from plants and other renewable agricultural, marine and forestry materials (USDA). Biobased refers to the amount of “new” versus “old” carbon. New carbon sources are considered organic, where carbon is bonded to hydrogen, full of active energy. An example of new carbon would be a tree. Old carbon sources are used, processed or spent. Examples of old carbon sources would be coal or Styrofoam (USDA). Using biobased products reduces the use of petroleum and promotes utilizing renewable resources instead. In turn, this reduces environmental and health impacts (USDA).



CONCLUSION


Growing with heavy fertilizers has been the standard way of growing for as long as we can remember. However, it has had lasting effects on our environment. Shifting towards an active sugar based growing method with a smaller quantity of NPK, can help reduce environmental impact. In addition, growing with sugars can help facilitate biological processes such as cell signaling, gene expression and initiate defense mechanisms. The chemical makeup of plants (96.6% carbon, hydrogen, oxygen and 3.4% salts), is the way nature intended it to be. In an effort to remedy the environmental damage created by agricultural practices, implementing active sugar based nutrient regimens is a step in the right direction, because active sugars give and sustain life.



References:

“Balanced Soil by SGS.”, 2018.

Bien, Brooke. “A Comparison of a Tannic Acid Biopesticide and a Commercial Fungicide Used for Crop Protection against Fusarium Head Blight.” Graduate School of Western Carolina University , Nov. 2016, pp. 1–75., libres.uncg.edu/ir/wcu/f/Bien2016.pdf.

Eckstein, Aleksandra, et al. “Sugar and Light Effects on the Condition of the Photosynthetic Apparatus of Arabidopsis Thaliana Cultured in Vitro.” J Plant Growth Regul, vol. 31, 2012, pp. 90–101., doi:10.1007.

“Eutrophication.” Wikipedia, 25 Sept. 2018, en.wikipedia.org/wiki/Eutrophication.

 Grattan, S R, and C M Grieve. “Salinity – Mineral Nutrient Relations in Horticulture Crops.” Scientia Horticulturae , vol. 78, no. 1-4, 30 Nov. 1998, pp. 127–157. Science Direct.

Julius, BT, et al. “Sugar Transporters in Plants: New Insights and Discoveries.” Plant Cell Physiology, vol. 58, no. 9, 1 Sept. 2017, pp. 1442–1460., doi:10.1093/pcp/pcx090.

(Julius, Leach, Tran, Mertz, & Braun 2017)

Lastdrager, Jeroen, et al. “Sugar Signals and the Control of Plant Growth and Development.” Journal of Experimental Botany, vol. 65, no. 3, 22 Jan. 2014, pp. 799–807., doi:10.1093.

McKenzie, Ross. “Crop Nutrition and Fertilizer Requirements.” Agri-Facts, Practical Information for Alberta’s Agriculture Industry, 1998, pp. 1–7.

“Molecule of the Week Archive: Tannic Acid.” ACS Chemistry for Life, 15 Jan. 2018, www.acs.org/content/acs/en/molecule-of-the-week/archive/t/tannic-acid.html.

“Organic Insecticide.” Www.patents.google.com, 6 May 1981, (https://patents.google.com/patent/US4361554A/en).

Patrick, John W, et al. “Metabolic Engineering of Sugars and Simple Sugar Derivatives in Plants.” Plant Biotechnology Journal, 2013, pp. 142–156., doi:10.1111.

“Plants: Essential Processes Topics.” Spark Notes, 2018, www.sparknotes.com/biology/plants/essentialprocesses/section2/.

Reece, J. B., Urry, L. U., Cain, M. L., Wasserman, S. A., Minorsky, P. V., & Jackson, R. B. (2011). Campbell Biology (9th ed.). Pearson Education.

Research on Sugar Application to Crops. 27 May 2015.

Rolland, Fillip, et al. “Sugar Sensing and Signaling in Plants.” The Plant Cell, American Society of Plant Biologists , May 2002, www.plantcell.org/content/14/suppl_1/S185.

Shrivastava, Pooja, and Rajesh Kumar. “Soil Salinity: A Serious Environmental Issue and Plant Growth Promoting Bacteria as One of the Tools for Its Alleviation.” Saudi Journal of Biological Sciences, vol. 22, no. 2, Mar. 2015, pp. 123–131. Science Direct.

“Understanding Aerobic and Anaerobic Respiration and Their Differences.” Biology Wise, 10 May 2018, biologywise.com/aerobic-anaerobic-respiration.

USDA. “What Is Biopreferred?” United States Department of Agriculture, USDA, www.biopreferred.gov/BioPreferred/faces/pages/AboutBioPreferred.xhtml


HEALTHY LIVING SOIL GIVES AND SUSTAINS LIFE
The Foundation of Sustainable Agriculture and Ecosystem Vitality