**Abstract**

Green Biosynthesis method was used for the preparation of Zn(II) nano complex from the reaction of the schiff base ligand 2,2′-((1E,1′E)-(1,2-phenylenebis (azanylylidene)) bis(methanylylidene))bis(4-bromophenol) and Zn(II)sulphate. The nano complex was characterized by different physicochemical methods. Zinc nanoparticles (ZnNP-T) will be studied as an antifungal agent. In this study, we will investigate the ability of the myogenic Zinc nanoparticles for plant Growth Promotion and Bio-control of *Pythium ultimum*.

**Keywords:** Zn-Nanocomplex, *Trichoderma harzianum*, *Pythium ultimum*, antifungal activity, *Trigonella foenum-graecum*

## **1. Introduction**

The rising interest of consumers for food integrity and for the social and environmental sustainability of agriculture systems has a special impact on the crop production fields. This circumstance forces us to look for new tools for crop protection that are not based on chemical control.

Since the rising demand production of organic food, using of biofertilizers and biopesticides were the best way to alternative eco-friendly production. In fact, *Trichoderma* spp. have the greatest resistant to pesticides, which categorizes as integrated control and good bio-control agents [1, 2] because of its ability to produce many enzymes, such as chitinases, glucanases and proteases. In addition to bio-control, *Trichoderma* spp. have been recognized as plant growth promoter and promoters of different plant defense mechanisms [1, 3].

Nanoparticles have very important role in the biotechnology industries [4], which considered one of the fastest growing fields because of their biological, chemical and physical characterization. The biosynthesis of nanoparticles complex from fungi are a significant branch, due to the fungi has the greatest tolerance and metal bioaccumulation capability. Biogenic methods for nanoparticles forming by plants [5, 6], fungi [7, 8], and bacteria [9, 10] have formerly been described.

A great promise in this area is the Schiff bases. A Schiff base can be defined as the nitrogen analogue of aldehyde in which the carbonyl group is replaced by the

azomethen group [11]. The transition metal complexes having O and N donor of Schiff bases ligands possess unusual configuration, structural liability, and are sensitive to the molecular environment [12].

Fenugreek (*Trigonella foenum-graecum* L) is an annual herb grown in North Africa, Egypt, India, Afghanistan, Bangladesh, Pakistan, Nepal, Iran, Turkey, Morocco, Spain, southern China and southern Europe. it is one of the commonly used herbs since ancient times. Medical Papyri of ancient Egyptian mentioned that it is used as food and antipyretic and in compounds used as incense for embalming and fumigation [13]. Several Arab writers described the plant and seeds as aperient, suppurative, emmenagogue, diuretic, useful in enlargements of spleen and liver, dropsy, and chronic cough. Fenugreek seeds contain 45.4% dietary fiber that blunts glucose absorption after a meal and regulate the production of cholesterol in liver [14, 15]. Seeds contain trypsine, alkaloids and chymotrypsine inhibitors [16, 17], anti-inflammatory steroidal saponin glycosides, flavonoids, furostanol steroidal saponins, flavone C-glycosides, spirostanol saponins and 17 amino acids, 7 of them being essential amino acids. Seeds considered as one of the most effective antidiabetic plants, used by traditional healers of northern Europe to treat diabetes, as stimulant and carminative, and in renal disorders. In Danish popular medicine, it is used to treat anxiety and depression. The seeds are used for wound dressing, rheumatism, stomachache, and leprosy, and have observed uterine stimulant activity [18].

However, its production may be affected by several exogenous stresses, including diseases caused by soil born pathogen microorganism. *Pythium* species affecting the different plants in younger stages and causing damping-off disease, this pathogenic fungi can caused root rot in later stages of plant growth [19, 20]. When the plant is in the seedling stage of its life cycle, infection by pathogenic *Pythium* species causes pre and post-emergence damping-off disease, which decaying the seeds and seedlings before and after the emergence of the plant from the soil surface, respectively. However, infected mature plants have also been found to show root rot symptoms.

*Pythium* spp. affect the young tissues, which have not developed to secondary thickenings; thus, the infection is limited to seedlings and youngest roots. The post-emergence damping-off disease of seedlings is associated with symptoms like water soaking, reduced growth, black or brown discoloration, wilting and root rot [21, 22]. In mature plants, water-soaked roots and lesions of stem at the soil line, stunted growth, and brown discoloration of roots are prevalent [23]. Due to their capability to disperse through different routes, their detection and Managements have become crucial. Therefore, the use of an integrated approach with bio and myogenic techniques for controlling of pathogenic *Pythium* spp. can be the most and best sustainable alternative to the traditionally used and dangerous chemical approach.

This study will focus on the management strategies of *Pythium ultimum* causing damping-off and root rot in Fenugreek (*Trigonella foenum-graecum* L) plants by preparation of Nano Schiff base complex, its characterization and its hopeful applications in different fields by using *Trichoderma harzianum*, which is a nonpathogenic, fast growing and environmentally friendly fungus. Therefore, the goals of the present study were: (a) to evaluate the pathogenicity capacity of nano metal complex against seedling. (b) to evaluate the tolerance of different concentrations of nano metal complex on the germination of seeds and possibility for acceleration of the growth and finally, (c) to evaluate the biosynthesis of nanoparticles complex for control of the disease caused by *P. ultimum* in seedlings.

*Biosynthesis of Zinc Nanocomplex Employing for Plant Growth Promotion and Bio-Control… DOI: http://dx.doi.org/10.5772/intechopen.100185*
