Breeding and Biotechnology of Plant and Flower
Farhad Shokouhifar; Mojtaba Mamarabadi; Sahba Toosi
Abstract
Introduction
Melon (Cucumis melo L.) is a diploid plant with (2n = 2x = 24) chromosomes, dicotyledonous and annual, which has been receiving lots of attention for its biological characteristics and economic value for a long time. Iran with production of about 1.6 million tons per year ranks third in ...
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Introduction
Melon (Cucumis melo L.) is a diploid plant with (2n = 2x = 24) chromosomes, dicotyledonous and annual, which has been receiving lots of attention for its biological characteristics and economic value for a long time. Iran with production of about 1.6 million tons per year ranks third in melon production in the world after China and Turkey. Vascular wilt caused by the soil borne fungus Fusarium oxysporum f. sp. melonis is one of the most important diseases causing damage to the melon plant. Due to the survival of this fungus in the form of chlamydospores in the soil and plant debris its control has been a difficult challenge so that, the only way to deal with this disease is to use resistant cultivars. The present study was conducted to characterize morphologically different melon cultivars with varying levels of resistance against Fusarium vascular wilt. Furthermore, the presence pattern of two MRGH genes belonging to the MRGH21 linkage group was tracked in the genome of the melon line, and their variations were defined. Moreover, the potential for using these genes in gene-assisted selection was investigated.
Materials and Methods
Five different varieties of melon named Charentais T, Charentais Fom1, Charentais Fom2, BG-5384 and the local cultivar Khatouni were grown under greenhouse conditions. Different characteristics of the plant, including leaf shape, male flowers, female flowers and normal flowers, and after harvesting the fruits, fruit weight, fruit diameter and length, diameter of flesh and middle cavity. The differentiation of resistant and sensitive cultivars was investigated based on the evaluated morphological traits. Additionally, the presence patterns of resistance genes were examined in the genomic data of the aforementioned melon cultivars. The genomic analysis of melons aimed to locate the MRGH21 linkage group, which carries several resistance genes. The sequence of this linkage group was tracked from two gene bank databases in NCBI and MELONOMICS database.
Results
Based on the obtained results, although it was possible to differentiate melon cultivars based on morphological traits, but since the study of these traits in the evaluation of a large number of samples in selective studies is a very time-consuming and costly task. Therefore, the presence pattern of resistance genes were analyzed in the genomic data of different melon cultivars. The sequence between two genes MRGH12 and MRGH13 including MRGH21 linkage group as one of the linkage groups carrying a number of resistance genes on Ch09 chromosome was retrieved form two gene bank databases in NCBI and MELONOMICS. Due to the presence of multiple point mutations in the genomic data, the MRGH13 gene sequence was selected for investigation in melon cultivars. Specific primers, PSh21-F/R, were designed to track part of this gene's sequence. The tracking results showed that a single specific band, corresponding to the expected size, could be detected in the cultivars Charentais Fom1 and BG-5384. Sequence analysis using the InterPro network tool confirmed the possible role of the protein coded by the MRGH13 gene. It was identified as a member of the protein family carrying leucine-rich repeat sequences, including the TIR, NB-ARC, and LRR domains.
Discussion
Attaining suitable markers to distinguish melon cultivars resistant to Fusarium wilt disease can support the development of breeding programs with higher accuracy and speed. The results of the present study showed that based on the morphological traits such as leaf shape, the presence of full flowers, and the number of petals, some differences can be observed between different melon cultivars, but the noteworthy point is that in selection programs searching for these morphological traits will be a very time-consuming and expensive task due to the large number of investigated samples. Therefore, if molecular markers related to the resistance trait are available, the efficiency of breeding programs is expected to increase significantly. In the present study MRGH13 gene was selected to be investigated for tracking in melon cultivars and specific primers were designed to track part of the sequence of this gene. The tracking results showed that a single specific band could be detected in the cultivars Charentais Fom1 and BG-5384. Biological processes related to MRGH13 protein in the QuickGO network tool showed its relevance in the signaling pathway that regulates immune responses. In future studies, it is suggested to evaluate the ability to distinguish resistant cultivars based on resistance genes, including the MRGH13 gene, in a larger number of samples. Moreover, considering to the predicted functions of MRGH13 protein, more investigation on its interaction with other resistance proteins as well as proteins of pathogenic agents can be useful for identification of its functional role in resistance.
Medicinal Plants
Tayebeh Baeradeh; Hossein Arouiee; Mahboobeh Naseri; Mojtaba Mamarabadi
Abstract
Introduction
Fruits and vegetables are perishable due to high humidity and biological activity after harvesting (breathing, transpiration and biochemical activities). Covering fruits with antimicrobial compounds, while being edible and safe for consumers, is an effective solution to prevent the spoilage ...
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Introduction
Fruits and vegetables are perishable due to high humidity and biological activity after harvesting (breathing, transpiration and biochemical activities). Covering fruits with antimicrobial compounds, while being edible and safe for consumers, is an effective solution to prevent the spoilage of fruits and increase their shelf life. In developing countries, packaging, storage and transportation technologies for these products have not been developed yet. One of the cheap and high-performance methods to increase the shelf life of fruit and maintain its quality during the storage period is to use a coating on the fruit. The purpose of coating application is to reduce water loss, slow aging, polish and better marketing. In addition to improving quality, coating can protect the fruit from pathogens and contamination. Edible coatings create a thin layer on the surface of the food that are effective and eco-friendly alternatives and maintain the firmness of fresh fruits and vegetables. The main components of edible coatings are natural polysaccharides, including starch, cellulose, pectin, alginates and chitosan. These coatings apply by spraying, immersion or rubbing. The use of essential oils and other extracts of medicinal plants has been evaluated in the development of edible coatings.
Adding Ziziphora tenuior L. essential oil to food has been considered as an antioxidant and antimicrobial compound. Directly use of essential oils for fruits and vegetable shelf life has some limitations due to low solubility in water, high vapor pressure and physical and chemical instability. One of the ways to reduce these limitations is the nanoencapsulation of essential oil as. Applications of nano technology to the development of edible coatings (included various nanosystems, including polymeric nanoparticles, nanoemulsions), efforts to control the release of essential oils. Aloe vera gel, which is extracted from the inner parts of the leaves, is clear, odorless, completely healthy and environmentally friendly and can replace the coverings used after harvesting fruits. This is a polysaccharide gel, it dissolves easily in water and has advantages such as preserving the aromatic substances inside the fruit, covering the wound and cuts and it is possible to add substances such as vitamins and essential oils to this gel. Due to the antibacterial properties of aloe vera, adding aloe vera gel to edible coatings can increase the antibacterial properties of this biodegradable coating. On the other hand, using nano technology can increase the efficiency, consistency and better quality of food coatings.
Materials and Methods
The aim of the present study was to prepare and produce an oral coating of nanoecapsule containing Ziziphora tenuior L. essential oil. The components of the nanocapsule of Aloe vera gel was water, toewin and Ziziphora tenuior L. essential oil. Fresh Aloe vera leaves were used to prepare gel. Zeta-average diameter, particle size distribution, scattering index (PDI) and zeta potential (particle surface charge) were measured. Transmission electron microscopy (TEM) imaging was used to evaluate the morphology of the nanocapsule. The stability of produced nanocapsule was evaluated by measuring the particle size changes for 3 months.
Results and Discussion
21 compounds were identified in the essential oil of Ziziphora tenuior. The main and important constituents of Ziziphora tenuior L. essential oil were Pulegone, Menthofuran and 1,8-Cineole. The results showed that the particle size of nanocapsule containing essential oil was 84.46 nm and zeta potential was -16.02 mV. The results of transmission electron microscope (TEM) photos showed that the size of the particles is less than 200 nanometers and the shape of the particles is almost spherical. The outer surface of the capsules is completely smooth and uniform. Stability studies of particle size and zeta potential for 3 months showed that nanocapsule containing essential oils had good stability. In this formulation, the zeta potential was about -16 mV, which is due to the non-ionic parts of the surfactant on the surface of the nanocapsule, which contributes to the repulsion force and caused the stability of the size of the nanocapsules. In order to determine the amount of essential oil in the nanocapsule, spectrophotometric method was used. The percentage of essential oil in nanocapsule was 83.25%.
Conclusion
Nanoencapsulation of essential is one of the ways to reduce the limitations of essential oil aplication. In the present study, a nancapsule with natural and biodegradable materials (Aloe vera gel) containing Ziziphora tenuior L. essential oil was prepared and the results showed that Ziziphora tenuior L. essential oil was successfully encapsulated in Aloe vera gel. In general, the results of the present study showed that the nanocapsule of Aloe vera gel is a suitable carrier for Ziziphora tenuior L. essential oil and can be used as an oral coating to preserve fruits and vegetables.
