Journal of Horticulture and Postharvest Research
Volume:3 Issue: 1, Mar 2020

In Tunisia, pear cultivars are widely threatened by the attack of fire blight disease. Cultivation of tolerant cultivars is an effective control strategy for disease control. For this purpose, a reliable protocol was established for micropropagation of local Pyrus communis and Pyrus syriaca L. and for large-scale production of high-quality plantlets. Research Using apical explants, different media and hormones were tested to establish a micropropagation procedure for local Tunisian Pyrus communis cultivars ‘Arbi’, ʻMaltiʼ, ʻMahdia 6ʼ and ʻMoknine 10ʼ and for Pyrus syriaca. Disinfection with 4% HgCl2 treatment for 20 minutes showed the highest percentage of plant survival. Successful initiation of the cultures was achieved on MS basal medium supplemented with 0.25 mg L-1 BA. During the proliferation stage, optimal shoot multiplication was obtained on MS medium with a half concentration of NH4NO3 and KNO3 supplemented with 0.1 mg L-1 IBA and 2 mg L-1 BA, but for maximum shoot length the BA concentration needed to be lowered to 1 mg L-1. A rooting rate of 100% and the highest root length and root number were attained on Cheng medium supplemented with 1.0 mg L-1 IBA. Pear vitroplants were successfully acclimatized on S2 substrate, composed by peat moss. Research limitations: Vitroplants acclimatization step needs to be well studied for the improvement of theacclimatized vitroplant survival rates by reducing the symptoms of crown rot. Originality/Value: This efficient optimized in vitro protocol will be successfully applied for large multiplication of high quality of Tunisian Pyrus vitroplants and cultivars.

The aim of this study was to investigate the effects of nano-chitosan and chitosan coating on physico-chemical properties of strawberries during storage. Research Fresh strawberries were coated with different concentrations of chitosan (1%, 1.5%. 2%) or nano-chitosan (0.2%, 0.4%, and 0.8%) and stored in 20C for 21 days. Coatingstrawberry with0.2% and 0.4% nano-chitosan preserved the overall quality index of the fruit up to 21 days. The treatments reduced weight loss, retained firmness, titratable acidity and L-ascorbic acid, significantly retarded malondialdehyde production and inhibited polyphenol oxidase activity of the stored fruit. The 0.2% nano-chitosan treatment reserved total soluble solid and total anthocyanin content better than the 0.4% nano-chitosan. Although 2% chitosan coating showed the positive effects, the overall quality index of the coated fruit was reduced below the acceptable level after 18 days, shorter as compared to the others coated with the lower concentrations of nano-chitosan. Research Limitations: Nano-chitosan, showing to be the effective coating material in this study, is not popular traded in the industry. Originality/Value: The combination of 0.2 % nano-chitosan coating and storing fresh strawberry at 2°C preserved the quality of fruits up to 21 days. The much lower concentrations of nano-chitosan showed higher positive effects as compared to the higher concentrations of chitosan. This would help to reduce the cost of postharvest handlings for the strawberry industry.

The tea plant is one of the most important products in the northern region of Iran, and plays an essential role in the region's economy. Since today many tea plants in the region are being destroyed for various reasons, so having information about the genetics of those trees helps design breeding programs to reach appropriate plants for specific purposes. Research SRAP markers, using eight primer combinations, were used to study the genetic relationships of 27 tea plant samples. In total, these eight combinations produced 41 scorable bands, 70.63% of which were polymorphic. The calculated PIC for all combinations was from 0.23 to 0.43 at an average of 0.36. Data analysis was performed by NTSYS software using Jaccard's similarity coefficient to determine the amount of similarity and the dendrogram was drawn based on UPGMA. Based on molecular data, the range of similarity between samples varied from 0.393 to 0.933. Samples were divided into five groups at a similarity level of 0.65. The fifth group (E) was divided into four subgroups at a similarity level of 0.75. Research limitations: Application of another marker system such as SSR and AFLP can help to understand the relationships of samples better. Originality/Value: In general, the study of genetic diversity showed that the SRAP marker could be useful in identifying polymorphic regions and estimating genetic distances and germplasm management in tea plants.

Rose cut flowers have a short postharvest life, which can be increased using different treatments. Thus, an experiment was designed to determine the effect of hot water (one min) and chemical solutions (pulse treatment for 20 h) on the postharvest quality of cut rose flowers cv. Baraka. Research Hot water treatments contain 50, 55, and 60 °C, chemical treatments consist of catechol (5 and 10 mM), sodium azide (0.05 and 0.1 mM) and sodium metabisulfite (5 and 10 mM). Afterward, for the evaluation of associated traits with longevity, the flowers were kept in a vase solution containing sucrose (3%) and hydroxyquinoline (8-HQ at 200 mg. L-1). The results showed that the vase life of cut flowers extended about four days by the application of chemical treatments as compared with control. The maximum vase life (9.9 days) observed in 0.05 mM sodium azide and 10 mM catechol (9.7 days). Also, the vase life of cut flowers increased 3.7 days by hot water treatments (at 50 and 55 °C) in comparison to the control. Moreover, the results revealed that the catechol, sodium azide and sodium metabisulphite treatments delayed flower senescence and maintained leaf chlorophyll and petal anthocyanin content. The lowest content of lignin was obtained in 10 mM catechol, and 0.1 mM sodium azide. Research limitations: There was no significant limitation to the report. Originality/Value: Overall, the results showed that catechol and sodium azide were the most effective treatments to increase the vase life of rose cut flowers.

One of the primary methods in increasing shelf life and maintaining the horticultural product quality is the application of edible coatings at the product surface. In this regard, this experiment was conducted to investigate the effect of tragacanth gum on some characteristics of pomegranate fruits such as weight loss, appearance quality, decay index, pH, soluble solid contents (SSC), titratable acidity (TA), maturity index, total phenol, vitamin C and anthocyanin content. Research

Fruits of two cultivars (‘Malase Yazdi’ and ‘Malase Daneh Siah’) were harvested and immersed in the tragacanth gum (0, 2.5, 5, 7.5, and 10 g l-1) solution for one minute. After applying treatments, fruits were air-dried, weighed, put in plastic baskets, and kept in the conventional storage in a completely randomized design for three months. Some quantitative and qualitative traits were measured and compared with the non-treated samples.

Results revealed using tragacanth gum had a different effect according to cultivar type. The results also showed that tragacanth gum coatings could control the reduction of fruit appearance quality, and reduce the number of fruit decay in the ‘‘Malase Yazdi’’. In ‘‘Malase Daneh Siah’’, coating with tragacanth gum could improve pH, SSC, TA, and total anthocyanin content. Phenol content in both cultivars increased at the highest concentration (10 g l-1) of this edible coating. Research limitations: No limitations were founded. Originality/Value: Tragacanth gum coating could improve fruit quality of pomegranate during traditional storage and can be recommended to traditional pomegranate gardeners who still have large-scale traditional pomegranate storage.

A study was carried out to determine the potentiality of Bridelia micrantha (BM) as biofumigant for the control of some economically important insect pests of stored food grains. Research BM powder was sequentially extracted with a series of solvents of increasing polarity in a Soxhlet apparatus and concentrated by the rotatory evaporator. The residues were dissolved in 50ml methanol, assayed for insecticidal activity by fumigant toxicity. Effective and active extract which showed maximum activity was selected for analysis using Gas Chromatography-Mass Spectrometry (GC-MS). Ethyl acetate crude extract and its active fraction (50% hexane: 50% ethyl acetate) showed more potent insecticidal activity with increasing concentration and exposure time. Among the insect species Tribolium castaneum is more susceptible and Rhyzoperthadominica tolerant of the fumigant toxicity treatments. GC-MS analysis revealed that Dibutyl phthalate (96%), 3-Dodecen-1-al (87%), 13-docosen-1-ol (83%) Ethanol-2-(2-butoxyethoxy) (80%), 2-Butenoic acid, 2 propentl (47%), 4-Hydroxyphenylacetic acid (38%) and Phenyl salicylate (30%) were the major constituents out of the eleven bioactive compounds identified. Research limitations: There were no limitations to report. Originality/Value: The results suggested that B. micrantha may be utilized as a good potential herbal fumigant for the management of stored product-insect pests due to its potent insecticidal activity and chemical composition which contains many different chemicals that have different modes of action on target pests and effective in the conservation of the germinative power of the various food grains.

The aim of this study was to formulate a new delivery system by the incorporation of Zataria multiflora. essential oil into solid lipid nanoparticles (SLN). Research SLN formulations were prepared following the high-pressure homogenization after starring and ultra-trax homogneization techniques. In this experiment, three SLNs formulations were prepared using three types of lipids. Lipids included glycerol monostearate lipid, precirol and stearic acid lipid. The SLNs were characterized by Differential Scanning Calorimetery (DSC), Transmission Electron Microscopy (TEM) and particle size analysis. The results showed that particle size, polydispersity index and zeta potential of the above formulations were about 255, 220, 486 nm, 0.369, 0.251, 0.296,-37.8, -17.6 -27.2 mV respectively. The results obtained from transmission electron microscopy (TEM) revealed that in all 3 formulations, particle size less than 200 nm were spherical. Thermal analysis by DSC, confirmed the presence of solid particles in the prepared SLNs. Also, the essential oil encapsulation percentage of Formulations 1, 2 and 3 were 85.3, 91.3 and 95.2% respectively. Stability studies of particle size and zeta in four months revealed that SLNs containing essential oils had relatively good stability. Research limitations: Limitations of SLNs are: Lipid particle growth, Unpredictable gelation tendency. Originality/Value: Due to the chemical structures of essential oils, EOs can be easily degraded after exposure to humidity, heat, oxygen, light, owing to chemical and enzymatic reactions. To overcome the drawbacks of EOs, several researchers have suggested the encapsulation of these active ingredients into nanocarriers. The results of the present research revealed that SLNs composed of glycerin monostearate lipids, precirol and stearic acid, were good carriers for Z. multiflora essential oil.

Quality and physical characteristics of date palm changes during growth and maturation stages of fruits in main production areas in the south of Tunisia. Research The effect of season, ripening date and climatic conditions (temperature and relative humidity) on physicochemical characteristics of fresh dates “Deglet Nour” grown at four different oases were evaluated using multivariate analysis. Main Dates from Traditional Mountain Oases (TMO) had the highest values of length, width, weight, moisture content for the two seasons. Those from Modern Palm Plantation (MPP) had the highest values of fiber content, water activity, glucose and fructose in 2014. In 2014 and 2015, date palm fruits of Modern Continental Oases (MCO) had the highest values of sucrose. The lower values of the different parameters were registered for dates from Traditional Continental Oases (TCO). Meteorological data from the experimental station recorded higher temperature and relative humidity during fruit maturation (July, August and September) in 2014 compared to 2015. Results showed that the good quality of dates was obtained in oases TMO that had higher relative humidity and lower temperature compared to other oases (MPP, MCO, and TCO). Such changes may have resulted from earlier pollination and higher temperatures during the maturation period. Considering the two seasons 2014 and 2015, the highest thermal coefficients were observed in MCO (3726 and 3704, respectively) and the lower ones in TCO (3083 and 3025, respectively). Research limitation: No limitations were founded. Originality/Value: Seasons and oases climate significantly affected the physical and biochemical quality characteristics of date palm fruits. This engendered in the longest maturity period recorded in TCO. MPP where we recorded the highest spring temperatures, showed the shorted development cycle.

The effect of foliar application of gibberellic acid and boric acid on bioactive compounds and quality of pomegranate fruit cv. Shishe-Kab was investigated. Research

This was accomplished through the field and laboratory experiments at the Faculty of Agriculture, University of Birjand, Iran, during 2017 and 2018 seasons. Gibberellic acid (50 and 150 mg L-1) and Boric acid (200 and 600 mg L-1) were applied three times at one-month interval; late in May, June, and July during growth and developmental stages of fruits. The experiment was set in a completely randomized block design. Fruits were harvested at full maturity stage late in October, and physicochemical properties were evaluated.

Results showed that anthocyanin content and antioxidant activity significantly decreased while fruit firmness, ascorbic acid content, and fruit cracking increased in gibberellic acid treatments. Application of 50 mg L-1 gibberellic acid significantly increased total soluble solids content and maturity index, but decreased titratable acidity in the fruits.However, foliar application of gibberellic acid and boric acid did not have significant effects on the pH and phenolic compounds of the fruit. Research limitations: Inability to examine different pomegranate cultivars in the investigation was a limitation. Originality/Value: Pre-harvest foliar use of gibberellic acid and boric acid showed positive and negative effects on postharvest quality attributes of Shishe-Kab pomegranate. Thus, further studies need for practical application.

In this study, the effects of different concentrations of salicylic acid on the physiological traits of Alstroemeria (Alstroemeria hybrida cv.ʻSummer Skyʼ) cut flowers during pre-harvest and postharvest applications are investigated. The aim of this study was to identify the best treatments and methods affecting the vase life of cut Alstroemeria flowers. Research

The study was performed as a factorial experiment based on a completely randomized design using three replications in each combination/mixed treatment. The factors comprised of the pre-harvest foliar and post-harvest (pulsing 24h and continuous) applications of salicylic acid at two concentrations of 30, 200 ppm (SA1) and 50, 300 ppm (SA2), respectively.

The vase life, chlorophylls a, b, and total, relative fresh weight, SOD activity, and the percentages of dry matter and the absorption of preservative solution were evaluated. The results showed that using high concentrations of salicylic acid (SA2) significantly increased the vase life of Alstroemeria. The pre-harvest foliar application of a 300 ppm of salicylic acid would be useful in prolonging the vase life of cut Alstroemeriaflowers and thus would help to reduce the losses caused by the rapid senescence of petals which will lead to an increase in the quality of appearance and economic value. Research limitations: There was no significant limitation to be reported. Originality/Value: The positive impact of salicylic acid (50 ppm) in the pre-harvest method (B) was found, and its application improved the vase life of cut Alstroemeria flowers, which should be taken into consideration for commercial uses.

The objective of this review is to study the effect of plant-based products on post-harvest management of the horticultural crops. Today when the horticulture crops are loaded with pesticides, the produce does not reach the consumer in a fresh and healthy form, it becomes imperative to look for alternative products which are safe, non-toxic, environment-friendly and does not disturb the eco rhythm. Plant-based products can be utilized at post-harvest stage washing agents, botanical sanitizers, edible coatings (protein, lipid and starch-based, anti-microbial agents, cushioning materials during transport, preservatives and as control measure for storage diseases as various bioactive constituents. To minimize dependence on synthetic pesticides, the use of plant-based antimicrobial substances which includes essential oils, glucosinolates, volatile compounds, acetaldehydes and jasmonates at various stages of plant growth may help in the management of crops, phytopathogens and pests in a very effective manner and will provide an alternative method for sustainable agriculture and opens up a new dimension of research for the scientists. Limitations: The author has used all the available resources but some excellent literature is still limited for including in the study due to non-availability to resources. Directions for future research: Plant-based products and botanical extracts opens up a new dimension of research. Scientists can easily utilize these for plant protection, cushioning, disease management during storage, extending the shelf-life. Scientists can standardize the edible coatings for various fruits, anti-bacterial, nano-emulsions based delivery of edible coating materials and aromatic extracts for disease management.

A safeguard program was organized to prevent and protect the autochthon fruit species in El Jerid Oasis, Tunisia. In this context, this study aimed to evaluate the grapevine varieties in these oases. Research A survey was conducted to detect the existing grape varieties and to count their stock. Ampelographic characterization of the bunch and berry (length, width, weight) and organoleptic analyzes (juice percentage, pH, TSS, titratable acidity) were measured for the most frequent founded vines. The study revealed a genetic wealth of vines in El Jerid Oasis, Tunisia represented by local and introduced table grapevines such as Muscat d'Italia, Cardinal, Superior Seedless, etc. The ampelographic characterization revealed medium-sized bunches for local varieties Chetoui, Arbi and Kahla and larger bunches for Muscat d'Italie, Sfaxi and Guelb Sardouk. Indeed, our grapevines were characterized by low weighted bunches. The varieties Guelb sardouk, Muscat d'Italie and Sfaxi showed berries with higher calibers and weights. The other studied vines had medium-sized and low-weighted berries. The local vines Kahla and Guelb Sardouk revealed fine-tasting berries with low sugar and acidity. Arbi and Sfaxi berries were richer in sugar with low acidity. Research limitations: No limitations were founded. Originality/Value: This study valorized the autochthone vines of El Jerid Oasis, Tunisia, by highlighting their fruit qualities, especially the taste. Therefore, the plantation of these autochthone vines should be favorized for grape table consumptions.