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Biofertilizers

One of the major concerns in today's world is the pollution and contamination of soil. The use of chemical fertilizersand pesticides has caused tremendous harm to the environment. An answer to this is the biofertilizer, anenvironmentally friendly (blue-green algae). The most striking relationship that these have with plants is symbiosis, inwhich the partners enefits from.

Plants have a number of orrhiza, rhizobium, and cyanophyceae. These are knownto deliver a number climatic conditions. echniques have proved to be successfulbiofertilizers that form a health relationship with the roots.

Biofertilizers will help solve such problems as increased salinity of the soil andchemical run-offs from the agricultural fields. come.

Mycorrhiza

Mycorrhizae are a group of fungi that include a number of types based on thedifferent structures formed inside or outside the root. These are specific fungi that match with a number of favourableparameters of the the host plant on which it grows.

drought tolerance, maintenance of water balance, and overall increase in plant growth anddevelopment.

While selecting fungi, the right fungi have to be matched with the plant. There are specific fungi for vegetables, foddercrops, flowers, trees, etc.

Mycorrhizal fungi can increase the yield of a plot of land by 30%-40%. It can absorb phosphorus from the soil andpass it on to the plant. Mycorrhizal plants show higher tolerance to high soil temperatures, various soil- and root-borne

pathogens, and heavy metal toxicity .

Legume-

Biofertilizers are living microorganisms that improve the heath and quality of different types of soils that

help the plants obtain the necessary nutrients. The soil becomes more nutritious and helps the seeds and

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roots grow to their full potential [1]. Biofertilizers activate the microorganisms that are found in the soil,

thus restoring the soils' natural fertility and protecting it against soil diseases and droughts, which stimulates

the growth of plants.

Additionally, biopesticides, or also known as Biological Pesticides, are natural pest control agents that are

obtained from natural substances [2]. They can come from minerals, plants, and bacteria. Using biopesticides has

advantages over using conventional pesticides, because biopesticides are less toxic to the environment and naturallife [3]. They play an important role in the protection of agricultural foods and protection against unwanted

microbial organisms [2]. Common Pests

What type of Bio-Fertilizers and Bio-Pesticides are there?There are many different types of biofertilizers and each type has a different effect on the soil, depending on

the crop people want to grow. The two types of bio-fertilizers that are commonly used are nitrogen and phosphorus

bio-fertilizers. Ultimately, they are the building blocks for any type of soil. Nitrogen biofertilizers can help balance the

nitrogen levels of the soil and help the growth of plants [1]. This is because plants need a certain amount of nitrogen

in the soil in order to thrive. Similarly, phosphorus biofertilizers work almost like nitrogen biofertilizers. This is due to

the fact that

The Nitrogen Cycle Inside the Soil

phosphorus is also an important factor for plant growth [1]. Phosphorus biofertilizers help the soil reachproper levels of phosphorus and also balance the phosphorus levels of the soil. However, unlike nitrogen

biofertilizers, phosphorus biofertilizers can be used for almost all types of crops and soils [1].

Furthermore, there are also different types of biopesticides, such as microbial and bi

ochemical pesticides. Microbial pesticides may contain specific types of

microorganisms such as fungus, bacteria and even protozoa, and each type can be used to utilize or target a

specific type of pest [2]. In the end, the results that show up can be significantly noticed. For example, some

types of fungi can kill certain types of unwanted weeds, while various types of bacteria can kill different

types of insect larvae, like flies, moths, and mosquitoes

[2]. Microbial Pesticides for Organic Farming

Microorganisms involved and the Metabolic Processes

Bio-Fertilizers

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First of all in biofertilizers, the four types of microorganisms that are involved are rhizobi

um, azola, azotobacter and the blue-green algae. Rhizobium are soil bacteria that

can fix nitrogen found in the air [4]. Inside the root, rhizobia can invade expanded cells of the cortex, and then

differentiate into nitrogen forming "bacteroides [4]. The amount of atmospheric nitrogen fixed varies with the

strains of rhizobium, plant species and environmental factors [4]. The nitrogen fixation within legume nodules results

from a complex metabolic exchange between bacteria of the

Rhizobium Leguminosarm

family Rhizobium and the plant host [5]. With this, carbon is supplied to the differentiated bacterial cells,

termed bacteroides, in the form of dicarboxylic acids to fuel nitrogen fixation [4]. In exchange, fixed nitrogen istransferred to the plant. Both the bacteroides and the plant-derived peri-bacteroid membrane tightly regulate the

exchange of metabolites [4].

Additionally, the azolla is a type of microorganism that mineralizes the soil nitrogen rapidly and is

made available to the crops in a very short period. Nitrogen released from azolla is

slow but steady, without leaching losses [4]. It also serves as a protein rich feed to fish and poultry [4]. Since they use

energy derived from photosynthesis to fix nitrogen, they are considered autotrophs and are also free-living

organisms [4]. The enzyme azollas metabolic process takes place through what it known as anaerobic Azolla

Filiculoides respiration. During this process, electrons are transferred from a reduced and an organic

compound to an inorganic molecule that does not include oxygen [6]. These acceptors are usually carbonate,

sulphate, and nitrate.

The azotobacter has the ability to improve the seed germination and plant growth of specific plants [4].

These microorganisms can also benefit crops by nitrogen fixation, the release of growth and by promoting

substances [7]. They have evolved a number of metabolic mechanisms to allow it to fix nitrogen. It has uniquely high

rates of respiration coupled with specific cytochromes to ensure that the enzyme nitrogenase experiences an

essentially anoxic, or a no oxygen environment [8]. It can also synthesise a protective 2Fe-2S protein that can bind to

nitrogenase

Azotobacter Vinelandii

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in conditions of oxygen stress to form an oxygen-stable complex that is inactive, but is protected from

damage [8].

Finally, the blue-green algae, also known as BGA, contain tiny gas vesicles in their cells, which regulate them

to float to the water surface or sink to the bottom in response to the changing of light and nutrient availability [4].

They can form a symbiotic relationship with azolla and fix the atmospheric nitrogen [4]. The BGA is associated with

the azolla occurring in a ventral pore in the dorsal lobe of each vegetative leaf [4].

Blue-Green Algae The endophyte, a bacterium, resides within the tissue of plants for at least part of its

life without causing apparent disease but it has the ability to fix atmospheric nitrogen [4].

Bio-Pesticides

Furthermore, in biopesticides, the two general microorganisms are

the Bacillus species and the plant incorporated protectants. Of the Bacillus

species, the most common used microbial pesticides are strains ofBacillus

thuringiensisalso knows as Bt. [9]. The different strains of this bacterium

produce different mix of proteins, and kills specific insect larvae. Other

species include bacillus thuringiensis Var. kurstaki, bacillus popilliae,

bacillus lentimorbus and bacillus sphaericus.These types of Bt. control

moth larvae on plants, and the strains are made specifically for the larvae of mosquitoes and flies [9]. The

Bt. produces a protein, which binds to the larvae gut receptor and causes it to starve[9]. Bacillus Thuringiensis

Whereas, the plant incorporated protectants, also known as PIP, are pesticidal substances that plants

produce from genetic materials that have been added to the plant [4]. Scientists can take the gene from Bt.

and introduce it to the gene of the plant, where the plant can then manufacture the substances that destroy

the pests. Ultimately, the two pesticides, the Bacillus species and the PIP mentioned above work

simultaneously in order to produce natural pesticides [4].

In addition to the m icroorganisms, the metabolic processes of all biopesticides

work in the same way. Each biopesticide consists of repellents that can drive the insects away from the plants by

their smell or taste. Also known as natural insect repellents, the biopesticides contain natural and plant based

compounds that release odours unappealing and irritating to insects [10]. Additionally, biopesticides contain anti-

feedants that cause insects feeding on the plants to reduce their food intake until they die from starvation [10]. In

female insects or pests, the ovipositor is a specialized organ that deposits eggs. Some plants contain Animage of an insect showing the ovipositor oviposition deterrent pheromones, which prevent the insects from laying eggs

on the plant [10]. This helps control the population of pests on crops. Finally, biopesticides also contain inhibitors

that can stop the development of different stages of insects [10].

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Pros and Cons

Advantages of Bio-fertilizersBio-fertilizers have been known to have many benefits to the environment with the help of science. For the

plants to be abl e to grow healthily, the many microorganisms that are in it help convert

the simple compounds to complex compounds and the organic materials safely [11]. This helps improve the soil

fertility and the natural habitat, as well as increase the crop yield by 20% to 30% [11]. They supply the plants with 25

% of nitrogen and phosphorus by replacing the chemical fertilizers, which can deteriorate the environment and alsocause harmful impacts on living beings. Ultimately, bio-fertilizers are environmentally friendly [11]. They not only

help provide protection against drought and soil-borne diseases, but also prevent from damaging the natural

sources, as well as cleansing the plant from precipitated chemical fertilizers [11]. The microorganisms that are

present in these bio-fertilizers can reduce Crops without the help of biofertilizers the stress in plants by competing

with the plant pathogens and suppressing them [12].

Since bio-fertilizers have excellent buffering capabilities and they contain organic matters, they can balance

the pH in the soil and reduce the acidity [12]. As they protect the soil from hardening, the organic matters that are

added also enrich the air aeration, water, and nutrient retention capacity [12]. They have the

ability to save water by retaining moisture and releasing it slowly. The microorganisms and the acids that are

found in bio-fertilizers have the ability to improve the plants health and hardiness when they enter the roots [12].

The organic materials and the acids that are found in the bio-fertilizers include humic and fulvic acids, organic fungi,

and organic fertilizer nutrients [12]. Humic acids are plant biostimulants that can increasesoil fertility, enhance

microbial activity and reduce water evaporation [13]. Crops with the help of Biofertilizers

Fulvic acids are the same, however, they have a lower molecular weight and higher oxygen

content [13]. The bio-fertilizers can help by supplementing other fertilizers as well as aid other organisms and

beneficial bacteria to grow and build soil [12]. This will improve seed germination and produce thicker roots. In

plants, bio-fertilizers also help stabilize the chlorophyll, which remits in photosynthesis by providing darker green

leaves and an increase in the carbohydrates content and the oxygen assimilation [12]. They also dont have any

unpleasant odours, so the society will not feel uncomfortable while using them [12]. In the economy, bio-fertilizers

are cost-effective and they also have low manufacturing costs, especially when it comes to nitrogen and phosphorus

use [11].

Disadvantages of Bio-fertilizersOn the other hand, sometimes bio-fertilizers arent readily accepted by the society primarily because

they do not produce quick and impressive responses [14]. However, this depends on the quality of the

product. Some bio-fertilizer packets may have insufficient population of microorganisms as well as high

https://sites.google.com/site/cronoteia/supermicrobes-assignment/bio-fertilizers-and-bio-pesticides/Green%20crops.jpg?attredirects=0https://sites.google.com/site/cronoteia/supermicrobes-assignment/bio-fertilizers-and-bio-pesticides/Green%20crops.jpg?attredirects=0

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levels of contaminants [15]. There may also be cases where the bio-fertilizers have insufficient amounts of

phosphorus and nitrogen, which can change the way the plants grow [5]. The results that the society sees can

alter their decisions further on buying bio-fertilizers.

Advantages of Bio-pesticidesIn addition to the bio-fertilizers are the bio-pesticides. There are three types of bio-pesticides that are

utilized frequently by most people. These include microbial pesticides, plant pesticides and biochemical

pesticides. The microbial pesticides have the ability to control insects, weeds, fungi, and bacteria that can

cause plant diseases [16]. The anti-microbial pesticides can control unwanted microorganisms on inanimate

objects in water and on selected food items [16]. These types of bio-pesticides are actually only chemicals

and they act by killing or inactivating microorganisms, such as pests that can cause diseases. An example of

this would include disinfectants, such as the ones used to clean swimming pools, drinking water supplies and

even in hospitals [16]. The plant pesticides are produced from genetic materials that are added to the plant,

instead of the plant growing them naturally [16]. They only target the pests that are living on the plants and

not the natural enemies of it, such as beetles and birds. Whereas, conventional pesticides can affect the

environment of many different organisms such as birds, insects and mammals. Moreover, they are not even

harmful to humans, and are cheap or even free if the plants are locally available. Finally, the biochemical

pesticides are the types of pesticides that naturally get produced by the plants and help control pests by non-toxic mechanisms [16]. These pesticides include plant growth regulators that may help the plant grow and

mate, or interfere with those processes [16]. These mechanisms also include substances that attract and repel

pests, such as pheromones or scents that humans smell from the plants. Therefore in general, bio-pesticides are considered to be less toxic that many other conventional pesticides

because, as mentioned above, they are naturally made pesticides by the plants [17]. When these bio-pesticides start

working, they are usually effective in very small quantities and often decompose fairly quickly. This is beneficial to

the environment because this results in avoiding the pollution problems, which most conventional pesticides cause

[17]. Additionally, they do not leave harmful residues, can be cheaper than most chemical pesticides and can also be

more effective than them in the long term [18]. A man using conventional pesticides

Disadvantages of Bio-Pesticides

Compared to bio-fertilizers, bio-pesticides have a few more disadvantages to them. If bio-pesticides

are ever used in large quantities, they can become capable of harming non-targeted organisms, including

humans [16]. Additionally, in order to even identify a specific pest or pathogen, multiple pesticides must be

used. This is because bio-pesticides have a very high specificity and cannot be used on any plant without it

being tested [18]. As a result, the constant use of pesticides can be very harmful for plants.

Also, since their reactions take place slowly, bio-pesticides would be very unsuitable if there is a

pest-breakout [18]. If they dont work effectively at that time, there is a possibility of being an immediate

threat to the crops. Besides that, the usefulness is also based on the environment they are in. Since bio-

pesticides are also living organisms, their efficiency is influenced by other biotic and abiotic factors [18].

Plus, if bio-pesticides, chemical or physical pesticides are constantly used, the targeted living organisms will

also evolve to have an increased resistance to their control [18]. The only way to remove this possibility is if

the targeted population is completely exterminated before they reproduce or they become incapable ofreproducing [18].

In conclusion, how are Bio-Fertilizers and Bio-Pesticides beneficial to the society and the

environment?

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Bio-pesticides and Bio-fertilizers are used widely by the agricultural society. This is because they are

beneficial to the environment the farmers work in. Since they are the opposite of conventional fertilizers and

pesticides, which include chemicals, they are greatly accepted.In the environment, naturally occurring pesticides and bio-fertilizers are known to cause less pollution than

other chemical ones. They are also known to reduce the amount of chemical fertilizers and pesticides that most

people use. And in most cases, they are not harmful to the society or to the organisms around the plant. These bio-

fertilizers and bio-pesticides also have the ability to produce greener and healthier leaves. Although, they may showslow results, the benefits are worth it.