Postharvest physiology
Pooran Karimi Tazeiji; Somayeh Rastegar; Hamed Hasanzadeh Khankahdani
Abstract
Introduction
Date fruit (Phoenix dactylifera L.) is one of the oldest known fruit crops and is considered as an important component of the diet in many Middle Eastern and North African countries. The fruit of date is nutritious, which is incredibly rich in carbohydrates, minerals, dietary fibers and ...
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Introduction
Date fruit (Phoenix dactylifera L.) is one of the oldest known fruit crops and is considered as an important component of the diet in many Middle Eastern and North African countries. The fruit of date is nutritious, which is incredibly rich in carbohydrates, minerals, dietary fibers and amino acids. Dates are one of the most important tropical fruits that play an important role in the country's economy. Among the date palm cultivars in Hormozgan province, Piyarom is one of the most commercial cultivars.
Recent studies by scientists have shown that the use of chemical compounds, in addition to environmental hazards, will cause various diseases in consumers due to the residual transfer of toxins to their bodies. Therefore, the management orientation of food preservation methods has moved towards reducing and eliminating chemicals and determining suitable alternatives, so that a certain time frame was set for the removal of some of the most important tobacco toxins.
In recent years, attention has been paid to aloe vera gel as a coating layer for fruits and vegetables to maintain their storage quality, and because it has no smell or taste, eating it does not pose a problem for humans and it is even good for health. L-arginine is one of the 20 major amino acids of living cells, which is a semi-essential amino acid in the human body. L-arginine and D-arginine are natural forms of common isomers of this type of amino acid.
The aim of the present investigation was the assess the effect of L-Arginine and Aloe vera gel edible coating on maintaining the external properties and the quality of semi-dried date fruit cultivars including Piyarom during storage.
Material and Method
The experiment was conducted as a factorial arrangement in a completely randomized design. The first factor was including seven treatments consisting of control, L-Arginine (1, 2, and 8 mM) and Aloe vera gel (25, 50, and 75%) and the second factor included storing (sampling) time for 9 months. In every measurement, the different attributes were evaluated such as weight loss percent; TSS; total acid; total phenol; flavonoid; color indexes including L*, a*, and b*; and antioxidant capacity. The level of antioxidant activity was evaluated by antioxidant agents by the method described by based on the trapping of free radicals of 2, 2-diphenyl 1-picryl hydrazyl (DPPH). DPPH solution was well combined with the methanol extract by means of a vortex and was incubated in the dark for 30 min. Then the absorption rate was read at 517 nm using a spectrophotometer. The color was determined using a colorimeter (Minolta, CR-400, Japan) after different months of storage. All measurements were done in triplicates. L* (100=white, 0=black), a* (–green, +red) and b* (–blue, +yellow) values were obtained at 400-700 nm range. The assay of the total phenol content was performed by applying the Folin–Ciocalteu colorimetric procedure. The total soluble solid (TSS) content of the fruit juice obtained for each replicate was determined using a hand-held refractometer Atago (Atago Co. Japan) at 25 °C; the results are expressed as % (°Brix). Titratable acidity (TA) was measured by titrating diluted juice with 0.1 N NaOH to a phenolphthalein end-point (pH 8.1-8.3). The results are expressed as citric acid %.
Results and Discussion
Based on the results, the treatments of Aloe vera gel and L-Arginine had significant effect on the quantitative and qualitative traits of Piyarom date fruits during storage. Storing time had significant influence (p<0.01) on the all parameters so that by passing storage time, the parameters including L*, a*, b*, a weight loss percent significantly increased and the parameters such as phenol, flavonoid and antioxidant significantly decreased. In the Piyarom cultivar, the treatments had significant effects on a*, b*, weight loss percent, phenol, flavonoid, and antioxidant, but it had no significant influence on TSS and total acid, so that the highest a* and b* color indexes was observed in the use of L-Arginine 1 mM, the greatest phenol and flavonoid in the application of L-Arginine 2 mM, the lowest weight loss percent in the use of Aloe vera gel 25 and 75%, respectively.
Conclusion
According to the results, 1 mM L-arginine treatment and 75% Aloe vera gel had a more effective role in maintaining the storage quality of Piyarom dates. The use of these treatments requires more extensive research on soft and dry dates.
Abdolnabi Bagheri; Hamed Hassanzadeh Khankahdani; Vajihe Ghanbari; Majid Askari Seyahooei; Seyyed Saeid Modarres Najafabadi
Abstract
Introduction: Assessment of genetic diversity in Mango can provide a platform to deepen our knowledge about its genetic background and determine the high quality genotypes for involving in the inbreeding programs. The high observed diversity among native landraces of mango can be used in breeding programs ...
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Introduction: Assessment of genetic diversity in Mango can provide a platform to deepen our knowledge about its genetic background and determine the high quality genotypes for involving in the inbreeding programs. The high observed diversity among native landraces of mango can be used in breeding programs to produce better cultivars and utilization of these cultivars as donor parent to transfer desirable characteristics to high-bearing cultivars. Suitable mango cultivars to prepare rootstock and scion and resistant cultivars against diseases and the high yielding cultivars (with regards to alternate bearing in mango) can be recognized by better understanding of available germplasms. In the past two decades in southern Iran, the process of producing the grafted mango trees via seed culturing and grafting suitable cultivars (What has been registered such as Sindary and Langra and what has not been registered) on the seedlings has been accelerated. Therefore, studying the diversity of mango germplasms in these regions can be a good way to identify and distinguish these genotypes. In the present study, native genotypes of mango from Minab and Rudan counties (Hormozgan Province) were collected, which are mainly produced through seed and over time they have been propagated by vegetative methods based on the quality and taste and their diversity, was evaluated using morphological attributes and molecular markers.
Materials and Methods: In this experiment, we studied genetic and morphological diversity of 39 mango genotypes collected from Minab and Rudan counties (Hormozgan province) using ISSR markers and morphological attributes. Morphological characteristics were assessed using IBPGR descriptor. DNA extraction was done using modified CTAB method. Similarity coefficient of ISSR markers was calculated by Jaccard’s procedure. Polymorphism information content (PIC) was calculated using PIC=2fi(1-fi) formula, where fi was frequency of the amplified bands and 1-fi was frequency of the null bands. In order to analyze morphological data SAS 9.1 software was used and the means were compared using LSD test. In addition, it was prepared a 0 and 1 matrix from morphological data and dendrogram of morphological attributes was designed using Jaccard’s similarity coefficient.
Results and Discussion: The dendrogram inferred from morphological characters grouped all genotypes in eight main clades in which similarity of the dendrogram ranged from 0.12 to 0.83 with mean value of 0.54. The least similarity was observed between Almehtari and Charak, and the most similarity was observed among Moshk, AnaMG, Noghal and HalMG. Analysis of 21 morphological parameters in the studied genotypes demonstrated being of significant differences among these genotypes in terms of morphological attributes (except flower density and inflorescence shape). The ISSR primers produced totally 145 scorable bands that the highest and lowest polymorphism band were observed in MI808 (20 bands) and MI827 (6 bands) primers, respectively. Average of PIC was 0.450. The similarity for ISSR markers ranged from 0.31 to 0.90, in which the least similarity was observed between Majlesi and Charak. However, the highest similarity was observed between Gilasi and KalanMB genotypes. It was observed the differences among same genotypes grown in the various regions. In Rudan region in due to better quality of irrigation water as well as sufficient and proper availability to irrigation water, growth conditions for mango trees is better than Minab region. These differences between Rudan and Minab regions in viewpoint of growth conditions can be reason of morphological diversity among mango similar genotypes in both regions, which it has been caused to incompatibility of morphological and molecular markers. For this reason, the genotypes that are genetically similar to each other may have different morphological differences and/or two homonymous genotypes in two regions have significant genetic differences. For example, Clanfar Baziari genotype, which had high genetic similarity (0.90) with Gilasi genotype, had morphological similarity coefficient equal 0.37 together. However Gilasi genotype collected from Ahmadabad Minab had same ecological similarity with Baziari region. In other instant, genetic similarity coefficient of AnaMG genotype was 0.85 with ShozMD, while in these genotypes had 38% morphological similarity. Correlation coefficient between similarity matrix of ISSR and morphological markers was 0.336 and not significant.
Conclusion: It seems that the observed high diversity among morphological attributes is intrinsically and stemming from mango propagation procedure in which mango genotypes highly diverged due to seed propagation. The high genetic diversity showed by morphological attributes was also corroborated by ISSR markers, indicating low environmentally influence-ability of the attributes.
