*2.3.2* Pseudomonas fluorescens

*P. fluorescens* bacteria represent a large and important group of Gram-negative bacteria that are present in large numbers as well as are free to live in soil, fresh water and salty environments, especially in the vicinity of the roots due to their ability to grow on organic materials that are abundant around the roots and many other natural environments,

It has received great attention within the term Induced Systemic Resistance (ISR) due to its effect on protecting plants treated with it as it is considered one of the most important types of root bacteria that stimulate plant growth [55], and in addition it has beneficial effects to promote plant growth. And that by providing the treated plants with many growth regulators, including gibberellins, auxins, and others [56].

Al-Fahad [57] has indicated that *P. fluorescens*, when used as a bacterial vaccine, has the effect of improving or increasing and stimulating growth, which is represented by increasing the leaf area, chlorophyll, in addition to stimulating the resistance of plants to infection with the virus or reducing its multiplication within plant tissues, and this positive increase was significantly and clearly reflected on the outcome.

Al-Fahad [52] mentioned that there are several theories that explain this stimulation, including the secretion of antibiotics by the stimulus factor outside or inside the plant. P.F bacteria were used in plant resistance as inducers against CMV, and it led to a decrease in the severity and rate of infection with the virus.

It grows at an optimum temperature of 20–30° C and most strains grow at 4° C [58]. Kazenpour [59] found that treatment in P.F with rice seed reduced the severity of rice sheath blight by 10.5%, while in comparison it was 52%.

#### *2.3.3* Spirulina platensis

We have been heading to thinking about resistance to viruses by stimulating resistance against it, due to the difficulty of controlling it by traditional methods. One way to enhance plant resistance against viruses is the use of the algae *S. platensis*.

It was recently classified by Ali and Saleh [60] and Kewi et al. [61] as a type of bacteria, **Figure 4**.

Kingdam (Domain): Eubacteria, Bacteri

**Figure 4. S. platensis** *form under a microscope.*

Phylum: Cyanobacteria Order: Spirulinalies Family: Spirulinaceae Genus: *Spirulina* Species: *Platensis*

Algae are ancient discovered organisms that date back to fossils about 305 billion years ago [62]. Its importance for health and the prevention of various diseases has been mentioned [63].

Spirulina is a bluish green algae that has a filamentous and spiral shape and its taxonomic position is unique because it combines Autorrphic [64], which is common in eukaryotic cells as well as bacteria and has high nutritional value, for example, vitamins B1, B2, and A [65]. The chemical composition is from proteins 55–70%, carbohydrates 15–25%, essential fatty acids 18%, minerals, vitamins, dyes, for example carotenoids and chlorophyll [60]. It was recently classified as one of the rare edible bacteria due to its low concentration of purine [66]. *S. platensis* is widely used as a nutritional supplement for human health, as well as animal feed, and its importance lies due to its high protein content of 60–70% and its high concentration of essential amino acids, fatty acids, minerals, vitamins and antioxidants [66, 67].

Blinkova et al. [68] showed that Sulfolipid extracted from *S. platensis* inhibits the activity of HIV and also consists of many amino acids and sugars and is considered essential compounds in addition to the micro and macro elements that have the essential role to improve plant growth [69].

Blue-green algae are highly efficient in producing a wide range of antibiotics that have a direct effect in inhibiting the growth of pathogenic bacteria. The anti-bacterial effect of marine algae is not limited to bacteria but also has an anti-viral effect [70]. Green algae have a high efficiency to produce a group of antibiotics and have a direct effect in inhibiting the growth of pathogenic bacteria P.sp., which is resistant to antibiotics. It is also considered one of the most important organisms due to its wide range and bioactivity including: This effect on viruses is inhibitory [71].

The results obtained by Buter and Hunter [72] have supported the addition of extracts consisting of seaweed to improve the growth and productivity of the plant, and that the process of foliar spraying through these extracts has led to an increase in vegetative and productive growth and the reason is to provide essential nutrients that the root cannot provide. Mishima [73] showed that *S. platensis* has the ability to inhibit the multiplication of many viruses.

Spenille and others [74] indicated that algae have significant effects as they increase the resistance of plants against disease, when added to the plant, and it is one of the most important organic sources used in plant production. The anti-effect of marine algae does not depend on the bacterium only, as it has an anti-viral effect [70]. Algae are important biological groups due to their wide range and biological effect, including the inhibitory effect against viruses [71]. The treatment of pepper plants with *S. platensis* had a positive effect in reducing the severity of ToMV mosaic virus, by reducing the phenotypic symptoms, the activity of the peroxidase enzyme, and the increase in leaf area, plant height, chlorophyll percentage, and dry weight of the shoots [75]. The United Nations Food and Agriculture Organization (FAO) as well as the independent governmental organization, www.iimsam.erg [76], recommended and emphasized the necessity of using SP as a basic and main tool to combat malnutrition in the world as well as to help achieve sustainable development. In India, some villages were working on the use of blue-green algae to improve the quality of saline soil in Samphar in Rajasthan, it is dried and used as fertilizer for crops such as wheat and barley. Gupta et al. [77] used some types of blue-green algae (*Arthrospira subsalsa & Spirulina Platensis*) with bio-fertilization and mitigation of salinity damage.

#### *2.3.4 Medicinal plant extracts*

Alternatives to chemical pesticides such as plant extracts have been used to protect plant production from diseases caused by fungal, bacterial, viral and nematode organisms, as they cause great losses to the economy during the growing season or in the post-harvest stages.

against fungi and bacteria and that these are isolated from Sespan, which have the

*The Activity of New Bio-Agent to Control* Cucumovirus Cucumber Mosaic Virus *(CMV)*

Albizia is widely spread in the world and the scientific name of Albizia is (L) Albizzia lebbeck and belongs to the family of Leguminosae. Its leaves are large and a

Leguminosae and is found in tropical Asia and is widely cultivated in other tropical and subtropical regions including Malawi [84]. Its flowers, bark, roots and stems

Albizia is an important plant as an important source of pesticides and because it contains important chemical compounds such as Saponins Alkaloids, Flavonids, Tannius [86]. The common name is bacha chin, ficus and acacia, and it is widely cultivated in the regions of tropical Asia, Africa and subtropical Asia [87].

It has many uses, including medicinal, environmental and economical, and is used as shade trees as well as wood production, and is considered to be of natural importance [88]. Its seeds contain lectins that are toxic to humans and animals.

The (Licorice) *Glycyrrhiza glabral,* which belongs to the Leguminosae family, and one of the most famous genera is the Glycyrrhizin plant, which contains 20

The plant spreads in Asia Minor and Turkmenistan in the east to Spain in the west, which are its original home and also because of its medicinal value It has become cultivated on large areas in France, Spain, Germany, Russia, Italy, China,

Al-Ajili [91] emphasized that licorice has high concentrations of amino acids as

well as carbohydrates and other important elements, which leads to its great importance in nutritional uses. Licorice, G. glabral, a type of the Leguminosae family, is of great medical importance, as it is used for treating stomach irritation, coughing, hoarseness, bladder and kidney inflammation, as well as gout and muscular rheumatism, the autumn season are among the best dates for collecting licorice, and the reason is because the active substances are more abundant in this season, and Autumn is the best time to collect licorice because the active ingredients

Chemical analysis of licorice extract revealed that there are phenolic compounds, terpenes, gummies, starch, and flavonids extracts due to phenolic compounds for resistance to the microbes *Candida albicans*, *Staphylococcus aureus*, and Mycobacterium semegmutis, and the effect of extracts of ten species, including licorice, which showed very high efficacy in inhibiting TYLCV, reaching 100% for

Licorice leaves are used to extract antimicrobial agents such as Pincembrin and Licoflavanone [94]. And the extract is used to protect against atomic radiation, as there is in the extract the substance alpha-amyrin that combines with the substance

Licorice contains many chemical compounds, as it is characterized by the availability of chemical compounds that have a sweet taste, and it contains Glycyrrheiel, Liguoric acid and flavonoids, including Glabridin and Glabrin [77]. Glycyrrhizin with its acid is the most important ingredient, it has an activity similar to that of steroid hormones, i.e. plant hormones are formed and thus lead to an increase in protein formation and an improvement in the indicators of vegetative

species. Glycyrrhiza, which means sweet veins in Greek.

Turkey and America as well as the Arab Gulf and Iraq [90].

fragrant group of yellow flowers and long seeds. It belongs to the family

effect of flavonoids [82, 83].

*DOI: http://dx.doi.org/10.5772/intechopen.96587*

are all used in medicine [85].

*2.3.4.3* Glycyrrhiza spp*.*

growth [89].

are more abundant [92].

all concentrations used [93].

**155**

*2.3.4.2* Albizia spp*.*

It was found that the extracts of pepper, geranium and datura plants have the ability to induce resistance to viral infection in the paper that was treated before inoculation with the virus, as well as act as infection inhibitors when mixed with the virus, and it was found that they contain compounds of partial weights, low and high that have effectiveness against viral infection [78].

#### *2.3.4.1* Sesabania spp*.*

The *Sesabania spp*. Belongs to the family of the leguminous Fabaceae or Leguminosae, and the leaf is a main compound, the stamens have many flowers and the fruit is a pod and contain a group of seeds. Therefore, many countries paid attention to this plant. Ndungiu [79] mentioned that there are many international institutions in East African countries that they have conducted a complete and comprehensive survey of the varieties that spread in countries, Malawi, Zambia, Botswana, Namibia, Zimbabwe.

*Sesbania sesban* Linn otherwise known as "Sesban" (**Figure 5**) is one of the six species of the genus Sesbania that is commonly found for cultivation in the tropical region of India. The plant is widely cultivated for its ability to stabilize nitrogen and wind shade, obtained good medicinal importance according to ethnomedical claims [80].

The plant contains many phytochemicals, including saponins terpenoids, which are fat compounds that are composed of the bindings of B-amyrin, Licoric acid and Glabrolide, Among them is Isoprene, Osiprene called Penta-hydrocarbon, Glycyrrhetol, Glycyrrhizin and Liguiritic acid. The effective natural products present in the plant S. sesban as a means of finding alternatives to the chemical pesticides manufactured because of the effective compounds this plant contains, which include phenolic compounds, including saponins [81].The leaves of the plant contain many important components that are found within the chemical components of the plant, including Alkaloidl, Flavonid, Tannius, Terpenad.

The use of this plant to get rid of pathogens by using it in the form of an alcoholic and aqueous extract or in the form of powder, and it also has high efficacy

**Figure 5.** Sesbania sesban *plants.*

against fungi and bacteria and that these are isolated from Sespan, which have the effect of flavonoids [82, 83].
