Journal of Horticulture and Postharvest Research
Volume:4 Issue: 3, Sep 2021

This study examined the efficacy of aqueous dips containing the amino acids, L-arginine, L-cysteine and L-methionine, to inhibit the senescence of six leafy green vegetables pak choy, coriander, choy sum, spinach, parsley and rocket.

Pak choy was dipped in amino acid solutions from 2-100 mM to determine the optimum concentration that inhibited senescence. The other vegetables were dipped in solutions with the optimal concentration. Senescence of the vegetables was assessed during storage at 10 °C in air containing 0.1 µL L 1 ethylene by determining loss of green colour (designated as green life), ethylene production and respiration rates.

For each amino acid, a dipping concentration of 5 mM was found optimal to inhibit senescence as shown by an extended green life and reduced ethylene production and respiration rates of all vegetables to a similar extent, except methionine which did not show a significant effect with rocket, and for spinach only reduced ethylene production.

Limitations: 

No limitations were encountered.

Originality/Value: 

Arginine and cysteine showed considerable potential for commercial use to extend the market life of many green vegetables and with their Generally Recognized As Safe (GRAS) status the amino acids should be a safe, consumer-acceptable treatment.

The texture is an essential feature of the nutritional value of fruit and vegetables and plays a critical role in the acceptance and success of these products by the consumer. However, mechanical injuries cause softening and abrasion in the mulberry fruit tissue during harvesting, difficult to assess. The experiment was conducted to estimate the mulberry fruit texture model by linear measurements for several harvesting conditions.

The mulberry may fall from the highest or middle branches or harvest by hand since three heights, including 0, 1.5, and 3 meters, were considered for both maturity stage, including purple and black stage, for dynamic loading experiments to measure texture in an orchard simulated ambiance. Mulberry fruits were stored at 3 °C for seven days. The abrasion area of mulberry fruit was determined by image analysis. Also, TA-XT PLUS Texture Analyzer (micro stable system, England) was used to perform the compression tests of mulberry fruits. Regression analysis of abrasion area versus practical factors (harvesting method, maturity stage, and storage time) was used to develop several models for assessing the area of fruit abrasion.

The combined effect of hot water for 3 minutes with 3% citric acid resulted in better quality fruits (less mass loss, less degradation of soluble solids, organic acids, and vitamin C), in addition to delaying the development of browning pericarp and pulp until the sixth day of storage.

Limitations:

 No limitations were founded.

Originality/Value:

 These models promisingly and accurately estimate the abrasion area of fruit without applying any inaccurate procedures, e.g., using a caliper in many experimental comparisons.

Modern onion breeding is almost completely based on the production of hybrid seed. This project was performed to evaluate the effectiveness of marker-assisted selection (MAS) in identification of the cytoplasmic types and Ms locus in 123 onion accessions. 

Research method:

Three cytoplasmic markers cob, accD and MK were used to identify the sterility (S) from the fertility (N) cytoplasm and four nuclear molecular markers (OPT, PsaO, Jnurf-13 and AcSKP1) were used for genotyping of Ms alleles.

The results showed that the two accD and cob markers were quite similar in the detection of the type of cytoplasm with 100% male sterility for male sterile lines and 100% fertility for maintainer lines. The MK marker was able to distinguish T-type cytoplasm as well. Based on the results, the frequency of fertility (N) was much more than the frequency of sterility (S and T) cytoplasm found to be 90% in Dorche (pop.1), 100% in Dorche (pop.2) and Kashan based on marker cob and accD and with MK marker, was found to be 80%, 90% and 82% in Dorche (pop.1), Dorche (pop.2) and Kashan, respectively.

Limitations: 

In this study, nuclear markers were not successful due to not finding linkage disequilibrium with the Ms locus, suggested more markers to be evaluated.

Originality/Value:

 Molecuar markers were very suitable for the indentification of S or N lines. Cytotype (N/S) determination of plants by usingmolecular markers (cob, accD and MK), could easily reduce the population size required for the production of onion hybrid seeds.

Motherwort (Leonurus cardiaca), a medicinal plant of the Lamiaceae family, has a great diversity and wide distribution in Iran. It is essential due to having leonurine with blood dilution and muscle relaxation effects.

To evaluate the response of the Iranian Motherwort ecotypes in drought environments, an experiment was carried out in split plot design based on RCBD with three replications. Three irrigation levels were considered as main plots, including %100, one-third, and two-third of field capacity, and four ecotypes as sub-plots including Kerman, Taleghan, Sarab and Khansar. The experiment was conducted at Horticultural Research Station, the University of Tehran, in Karaj.

The results showed that water stress affected morphological traits significantly. Water stress had a significant increasing effect on the phenolic and flavonoid contents and antioxidant activity of Motherwort ecotypes. The highest and the lowest total phenol content were observed in Taleghan and Kerman ecotypes, 7.34 and 4.21 mg/mg fresh weight, respectively. The amount and the percentage of leonurine were increased by water stress. The highest and the lowest values of leonurine were observed in the ecotypes of Taleghan and Sarab, respectively, in all three levels of irrigation. There were significant correlations between dry weight (-0.43), antioxidant (0.36), proline (-0.35), catalase (0.4), and the percentage of leonurine.

Research limitations: 

There were no limitations to the report.

Originality/Value: 

It was found a significant variation among the ecotypes in response to water stress. The ecotypes of Taleghan and Sarab were the most tolerant and the most susceptible ecotypes to drought stress among the studied ecotypes.

To increase yield and quality of fruit vegetables under high pressure of soil-borne pathogens, nematode, and unfavorable environments introducing vegetable grafting in agriculture are crucial. It also helps to reduce disease susceptibility and to increase tolerance against abiotic stresses.  

Grafting in vegetables is a centuries-old practice to improve yield through organic culture. It was introduced in USA and becoming more common in organic farming of vegetables. Vegetable grafting is popular practice in many European and North American countries, Japan, Korea, and China. Vegetable crops are exposed to many abiotic and biotic stress factors, including salinity, heat, heavy metals, excess trace elements, diseases, and pests, which have a significant effect on crop growth and productivity. Grafting is effective practices in solanaceous and cucurbitaceous vegetables to control soil-borne diseases including; Verticillium wilt, Fusarium wilt, and bacterial wilt, and nematodes without using pesticides.

Limitations:

 Despite of its numerous benefits, there are several difficulties associated with grafting which include added cost, graft mismatch, physiological complaints, and reductions in flower formation, quality, and yield of fruit.

Directions for future research:

 Appropriate selection of scion and rootstock, scion–rootstock communication, and the reciprocal effect of the shoot and root system should be considered to get maximum benefits from this novel technique. New research should be conducted to evaluate and test diverse germplasm as a source of the viable rootstock, development of grafting tools ideal for the stable, year-round, and cost-effective yield.

The purpose of this study was to investigate the adhesion of Penicillium italicum and Penicillium digitatum spores on four materials commonly used in the citrus packaging chain (plastic, PVC, stainless steel, 316L and wood).

The physicochemical characterization of spores and material surfaces was carried out using the contact angle method. The number of adhered spores was estimated after being detached from supports in an ultrasonic bath. The results showed that all citrus materials processes were classified as hydrophobic except for the wood packaging. Surface spores of P. digitatum presented a relatively hydrophobic character, and surface spores of P. italicum presented a hydrophilic character. Both of the spores and all materials presented high electron donor/acceptor characters.

The results showed that P. digitatum and P. italicum sporescould adhere to all the studied substrates. Furthermore, the highest adhesion was observed by  P. italicum and P. digitatum spores on wood packaging (58 Î 106 CFU/cm2) and (45 Î 106 CFU/cm2), respectively. The wood packaging was the least hygienic material concerning the adhesion ability of P. digitatum and P. italicum spores, followed by plastic packaging, PVC, and 316 L stainless steel. A correlation between substratum physicochemical properties and spore adhesion was also examined, while a good correlation was observed between spore adhesion and donor electron character.

Research limitations: 

There were no limitations to this study.

Originality/value: 

This research studied the adhesion of spores on materials commonly used in the citrus packaging chain.

This study aimed to valorize the grape genotypes in the oasis of Tozeur, Tunisia, by exploring their salinity tolerance.

The principal genotypes: Arbi, Chetoui, Guelb Sardouk, Kahla, Sfaxi and Muscat d’Italie were subject to two salt treatments: a gradual stress by adding 25 mM NaCl every week until the final doses of 75,100 and 150 mM NaCl and a shock by applying 50 and 100 mM NaCl from the treatment onset. The shoot length and the number of leaves were monitored during salt treatments.  

The first mortalities were registered at the 3rd week for Sfaxi under gradual stress conditions, Guelb Sardouk, and Kahla under salt shock. The effects of 75 mM NaCl gradually added were expressed only by the decline of leaves number for the genotypes Chetoui, Kahla, and Sfaxi, while those of low salt shock (50 mM NaCl) were manifested by plant height and leaves number reductions. Salinity damages were aggravated by increasing the salinity. Another response was observed for the studied genotypes: they kept their vegetative apparatus almost unaffected to preserve the photosynthetic capacity.

Research limitations:

 No limitations were founded.

Originality/Value: 

The adverse effects of salinity were more relevant at the end of the stress particularly under the high salt dose (150 mM NaCl). The salinity of irrigation water for our grape genotypes shouldn’t reach 150 mM NaCl. The genotype Arbi was the most tolerant genotype while Kahla was the most sensitive to salinity.

The evaluation of the response of three old pear cultivars (’Meski Arteb’, ‘Bouguedma’ and ‘Alexandrine’) to drought was performed through some physiological traits and leaf characteristics. This work aimed to highlight the behavior of these cultivars under water stress conditions.

The experiment was carried out in a greenhouse under controlled conditions by the application of three water stress levels as a complete randomized block. Plants showed moderate water deficit after 10 days without watering and severe stress after 20 days without watering. Control plants were kept well watered.

Data showed a similar cultivar response to water stress but with various degrees. The relative water content and the water potential of leaves decreased with the water stress severity in all cultivars. Stomatal conductance and photosynthetic assimilation followed the same path with water status parameters, and ‘Alexandrine’ showed the highest level of gas exchange parameters. Chlorophyll content and total soluble sugars concentration of leaves decreased in response to drought increase. However, the proline content and leaf characteristics were unaffected except for ‘Bouguedma’ cultivar for which leaf area and succulence were reduced under severe stress.

Limitations: 

No limitations were founded.

Originality/Value: 

the three cultivars behaved differently against drought, these traits can be exploited for further breeding programs to face climate change impact.

Twenty genotypes of okra including hybrids and open pollinated varieties both from local and exotic sources were evaluated in the field to study their yield performance and disease response.

Experiment was conducted following randomized complete block design with three replications.

Analysis of variance indicates significant variation among the okra cultivars for all the characters’ studied except days to first germination. The highest number of fruits per plant (19.98) and maximum yield of green fruits per plant (279.59 g) and maximum yield (1.33 kg/m2) was obtained in the genotype G4 (F1-hybrid) followed by G7 and G18. The maximum edible fruit length was observed in G7 followed by G19 and G15. The maximum number of seeds perfruit was recorded in G4.The highest 100-seed weight was found in G4 followed by G17. On the contrary, the lowest seeds per fruit, 100-seed weight, and green fruit yield per plant were obtained from G6. The highest incidence of yellow vein mosaic virus (YVMV) was observed in the genotype G6 and the lowest in the genotype G19 followed by G8, G2, G4, G17 andG12. The cluster analysis grouped 20 genotypes into five cluster and maximum number of genotypes included in cluster 5. Strong positive correlation was observed between yield per plant and days to 50% germination, germination percentage, number of seeds per fruits and 100-seed weight (g).

Limitations: 

No significant limitation to the report.

Originality/Value:

 The results help to identify the suitable okra genotypes and generate breeding materials.

This study was conducted to identify the physiological disorders and their symptoms of selected Citrus fruit species (C. sinensis, C. limon and C. crenatifolia). Furthermore, it was aimed to determine whether physicochemical and sensory properties were affected by physiological disorders.

Citrus fruits with physiological disorderswere observed separately for visible changes and characters were recorded and photographed. Moreover, Citrus fruits with physiological disorders were analyzed for physicochemical and sensory properties.

Many physiological disorders were recorded from three Citrus fruit species including chilling injury, sun burn, stem-end rind breakdown, oleocellosis, rind disorder, puff and crease, granulation, wind injury, peteca, fruit splitting and fruit cracking. Based on the overall result of sensory analysis, it can be concluded that most of the physiological disorders in studied Citrus species appear on the peel but not adversely affect the edible internal portion of the fruits. Physicochemical properties of C. limon are not adversely affected by physiological disorders whereas C. sinensis and C. crenatifolia are affected by physiological disorders.

Limitations: 

Availability of selected Citrus fruit species throughout the year is limited due to their seasonality.

Originality/Value:

 This study provides novel information about the physiological disorders of some Citrus species in Sri Lanka and other parts of Asia and a future potential exists in controlling these disorders to provide healthy and quality fruits to the market.