Volumen 27 (2019): Edición 2 (December 2019)

Developing a method for the control of cut flower opening and improvement of cut flower quality is important to meet consumer demand. In this study, we investigated the effects of methyl jasmonate (MeJA) on flower opening of three rose cultivars: ‘Red Star,’ ‘Princes Meg,’ and ‘Madrid’. Shoot bases of cut roses were immersed in water solutions containing 100- or 1000-μM MeJA in addition to 2% weight/volume (w/v) sucrose and 0.02% w/v 8-hydroxyquinoline monohydrate. Subsequently, the vase life, flower opening, petal wilting, petal weight, water uptake, and water evaporation were measured. Flower opening of all three cultivars was clearly delayed following the treatment with MeJA, resulting in prolonged vase life compared with control. In addition, flower wilting was suppressed in all cultivars. Moreover, 7 days following treatment, the petal fresh weight was maintained high in the ‘Red Star’ and ‘Princes Meg’ cultivars. However, there was no significant difference in the ‘Madrid’ cultivar versus control. In all three cultivars, there was a minimal difference in the total amount of water uptake and evaporation. Thus, it is suggested that the total amount of water uptake and evaporation have limited relevance to the changes in the relative fresh weight of cut roses and petal fresh weight observed following treatments. Despite the difference in the sensitivity of the rose cultivars to treatment with MeJA, we conclude that MeJA has high potential as a quality retention agent for cut roses.

Microorganisms play an important role in the propagation and growth of plants. Propagation of plants through stem cuttings is a popular method widely practiced in horticulture and forestry. As the information on the interactive role of arbuscular mycorrhizal (AM) fungi and phosphate-solubilizing bacteria (PSB) in the regeneration and growth of clonally propagated plants is limited, we inoculated stem cuttings of Impatiens walleriana with Rhizophagus fasciculatus and Bacillus megaterium var. phosphaticum individually or in combination in an unsterile Alfisol field soil. The inoculated cuttings were harvested after 45 days of cultivation and various growth parameters and phosphorus (P) uptake were measured. Inoculation with the AM fungus or PSB individually improved plant growth parameters, whereas the dual inoculation did not give synergistic results. Plants inoculated at cutting stage with R. fasciculatus accumulated the highest plant biomass and showed maximum microbial inoculation effect and efficiency of P uptake. Inoculation with the PSB stimulated symbiosis with native AM fungi but a synergistic effect has not been found when both AM fungi and PSB were co-inoculated. It could be concluded that screening for compatibility between microorganisms is essential before selecting the bioinoculants for dual inoculation.

The aim of the present investigation was to optimize protocols for micropropagation and adventitious shoot regeneration from leaf explants of two wild ecotypes of red flesh apple Malus niedzwetzkyana for future breeding programs. At the proliferation stage, different concentrations of sodium nitroprusside (SNP) and triacontanol (TRIA) were compared. To optimize shoot regeneration from leaf explants, interactive effects of 1-phenyl-3-(1,2,3-thidiazol-5-yl)-urea – thidiazuron (TDZ), indole-3-butyric acid (IBA) and two explant types were investigated. At rooting stage, the effect of exposure time of microshoots to darkness and exposure time to different concentrations of IBA and α-naphthalene acetic acid (NAA) were compared. The results showed that SNP affected the growth rate significantly and the maximum multiplication rates per explant (9.6 in the first ecotype and 8.8 in the second) were produced in the Quoirin and Lepoivre medium containing 17 SNP µM, in addition to 4 µm 6-benzylaminopurine (BAP) and 3 µm gibberellic acid (GA₃). IBA and TDZ affected the adventitious shoot regeneration from leaf explants significantly, the highest number of regenerated shoots (18.3 per explant) was obtained from the basal section of the leaves cultured on the medium containing 2 μM IBA and 15 μM TDZ. At rooting stage, the maximum rooting (88.6%) was obtained in the result of one weak exposure to darkness on medium containing 3 μM IBA.

To study possibility of protection of sweet cherry fruit against cracking several rows of ‘Lapins’ sweet cherry (Prunus avium L.) trees grafted on ‘Colt’ rootstock, spaced 5 × 2.5 m and trained to a central leader were covered with a plastic foil to a height of 5 m. Several rows were left uncovered as a control. In the years 2016 and 2018, sun irradiation, air temperature and fruit quality were evaluated. The plastic cover reduced solar irradiation under the tunnel roof by around 40%. Light distribution within tree canopies was depleted by roughly 50%, but in the lower parts of the tree canopies, it was reduced to 6%, which is below the critical level (20%) estimated for apple trees. These results indicate the necessity to remove the covers as soon as possible after harvesting. Mean daily temperature near the ground was lower under the covers than outside, but at the height of 4.0 m, daily mean temperature was 0.4 °C higher and mean temperature during midday hours was 1.5 °C higher. The plastic covering reduced the fruit cracking from about 20% to 2% in both seasons but did not affect the fruit yield. The plastic covering did not affect the firmness and antioxidant activity and total anthocyanin content, but in the year 2018, it reduced the mean fruit weight, soluble solid, titratable acidity, dry matter and total polyphenols content.

Jujube fruit quickly undergoes spoilage and normally has a short shelf life. Therefore, the effect of immersion treatment in different calcium salts on qualitative and biochemical characteristics of fresh jujube fruit was evaluated. Treatments included control (distilled water) and solutions of calcium chloride, calcium nitrate, and calcium sulfate at a concentration of 0.5 and 1%. Fruits were immersed in water or calcium salt solution for 5 min, air-dried and then cold stored at 4 °C for 50 days. The results showed that such treatment did not affect significantly the pulp color and the anthocyanin concentration in the fruit. However, the soluble solids in the treated fruits significantly decreased compared with the control. Interestingly, all levels of calcium salts, except 0.5% calcium nitrate, preserved the total antioxidant capacity in comparison with the control. Concentrations of 1% calcium nitrate, chloride, and sulfate significantly increased crispness compared with the control. The taste of fruit treated with calcium sulfate significantly deteriorated compared with the control and other treatments. In general, 1% calcium nitrate and 1% calcium chloride applied before storage preserved or strengthened the jujube fruit qualities after storage compared with control. It can be concluded that such treatment is recommended for practical application.

In this study, ‘Rabbab’ pomegranates (Punica granatum L.) were subjected before storage to single-layered wax coating (SLW), double-layered wax coating (DLW), individual-seal film packaging (ISP), tray wrap film packaging (TWP), and combined treatments of SLW + ISP or SLW + TWP. Treated fruits were then stored at ambient temperature (15–20 °C; 45–50% relative humidity – RH) or in cold conditions (5 °C ± 0.5; 85% RH) for 18 weeks. TWP, ISP, DLW, and SLW extended the shelf life of pomegranates for 18, 18, 12, and 11 weeks at cold (5 °C) condition, and also for 6, 5, 3, and 3 weeks at ambient condition, respectively, whereas the shelf life of control fruits were 10 and 2 weeks at cold and ambient conditions, respectively. After 18 weeks of storage, the weight loss in ISP and TWP fruits was 0.6 and 0.4% at cold condition and 12.4 and 5.4% at ambient condition, respectively. In general, film packaging maintained vitamin C, total titratable acidity, and sensory analysis scores for color, freshness, juiciness, and taste of pomegranates more effectively than wax coating and control. However, the combination of SLW and ISP or TWP did not improve the efficiency of pomegranates packaged as either ISP or TWP.

The aim of this study was to evaluate the fruit quality of 13 Asian pear cultivars grown in climatic conditions of central Poland. The following cultivars were tested: ‘Chojuro’, ‘Hayatama’, ‘Hosui’, ‘Kosui’, ‘Yuan Huang’, ‘Nijisseiki’, ‘Dżin Li’, ‘Er Shi Shinge’, ‘Er Jang Li’, ‘Golden 20^th’, ‘Min Czi Li’, ‘San Li’, and ‘Shinseiki’. Pears were harvested in Experimental Orchard of Research Institute of Horticulture in Dąbrowice (near Skierniewice). Fruits were stored for 10 weeks at 0 °C in regular atmospheric conditions. Flesh firmness (FF), total soluble solids (TSS), and titratable acidity (TA) were measured at harvest and after the storage followed with 1 and 7 days of shelf life (SL) at 18 °C. After the storage, the sensory evaluation was also performed. Among the tested cultivars, ‘Min Czi Li’ and ‘San Li’ were the most firm (above 45 N) and ‘Kosui’ was the least firm (below 28 N) at harvest time. High amount of TSS (above 11% in both seasons and harvest dates) was observed in ‘Chojuro’, ‘Hayatama’, ‘Kosui’, ‘Yuan Huang’, and ‘Er Jang Li’ pears. Low TSS (not more than 10.6% at harvest) was observed in ‘Nijisseiki’, ‘Dżin Li’, and ‘Er Shi Shinge’ cultivars. The large differences among cultivars were observed in TA. High TA was observed in ‘Nijisseiki’ (above 0.32% in all terms of analyses) and low TA in ‘Hayatama’ and ‘Kosui’ (below 0.14%). All of the evaluated cultivars can be stored for 10 weeks at 0 °C in regular atmosphere without major negative impact on their quality characteristics. Fruits showed a slight (sometimes significant) decrease in FF after storage and a slight or no changes in TSS and TA. In sensory evaluations, ‘Chojuro’, ‘Hayatama’, ‘Hosui’, ‘Kosui’, ‘Yuan Huang’, ‘Er Jang Li’, ‘Er Shi Shinge’, and ‘Shinseiki’ (mostly cultivars characterized by high TSS) obtained highest scores for the overall quality (above 5.0 points in 10 points scale).

Corrugated cardboard covered with ethylene absorbers is an innovation that can be used to extend the shelf life of mango fruit to slow the loss of fruit quality. Mango fruits ‘Gedong’ were placed in boxes having as the inner parts corrugated cardboard covered with ethylene absorbers. Three storage treatments – corrugated cardboard without ethylene absorber, with activated carbon or activated carbon + potassium permanganate – were used to find the best method to prevent quality deterioration of mango. The color change, mass loss, texture value, and total soluble solids content were evaluated after 10 days of storage. The initial results showed that the highest accumulation of ethylene production by fruit samples was 0.628 ppm·kg⁻¹ on the fourth day after harvest, while the total ethylene production during 8 days of storage was 2.231 ppm·kg⁻¹. The use of ethylene absorbers had significant effects on the quality parameters except for the color changes. Storage for 10 days in boxes lined with corrugated cardboard ethylene absorber in form of activated carbon + potassium permanganate resulted in the lowest mass loss (4.40 ± 2.6%), softness (0.2 ± 0.1 mm·g⁻¹·s⁻¹) and total soluble solids (14.7 ± 1.2 °Brix).

For many years Poland and Serbia have played the dominating roles in European raspberry production. However, the growing production in Ukraine might threaten the relative stability of the raspberry market for both countries. It is projected that in the coming years Ukraine will strengthen its competitive position in relation to the current industrial raspberry production leaders. This justifies the need to conduct comparative analyses of competitive power, and its contributory factors, including production costs in individual countries. The aim of this study was to compare economic viability and cost-effectiveness in raspberry production, using the examples of selected horticultural holdings in Poland, Serbia, and Ukraine. The production volumes of raspberries in Poland, Serbia and Ukraine were analysed. The levels of costs and the financial results generated in raspberry cultivation for processing purposes were also determined, using the example of horticultural holdings in this countries. The results indicated that the direct costs in Ukraine, were just over half lower those in Poland and Serbia. The raspberry crop yields in the three investigated countries were similar, and the sales prices in the analysed years made it possible to obtain a surplus of receipts over direct costs.

Good knowledge of genetic merits governing the inheritance of economic traits is of paramount importance to plant breeders for crop improvement. Objectives of the study were to investigate the genetic nature of ear traits in sweet corn (Zea mays convar. saccharata var. rugosa) based on the general and specific combining ability (GCA and SCA) analysis, and to determine the breeding potential of eight promising inbred lines for the development of new hybrid cultivars well suited for organic production. Thirty-six genotypes (hybrid families) derived from a half diallel cross design were grown under organic crop management at three agro-ecological zones of the tropics. Although the genotypes varied significantly for all the observed ear traits, some of them showed clear inconsistencies in performing husked ear size (length, diameter, and weight), kernel row number, and kernel number per row across environments. The combining ability analysis showed that additive gene action was more preponderance than non-additive gene actions in governing the inheritance of the studied ear traits. The inbred lines: Caps 5, Caps 17A, Caps 17B, and Caps 22 showed their potential as good partners for the improvement of ear performances as to the development of superior sweet corn cultivars for organic production.

Haploid induction using in vitro cultures of unpollinated flowers has been recognized as an important tool to produce homozygous plants for genetic studies and breeding programs. In this study the potential of gynogenic haploid induction in four ecotypes of Allium hirtifolium under different combinations of benzylaminopurine (BAP) with 2,4-dichlorophenoxyacetic acid (2,4-D), or α-naphthaleneacetic acid (NAA) was investigated. Unpollinated flower buds were excised from an umbel 5 to 3 days before anthesis, and cultured onto B5 medium containing 7.5% sucrose and 2 mg·dm⁻³ BAP with auxin. The experiments revealed that NAA increased the percentage of gynogenesis induction and number of gynogenic embryos per flower in all ecotypes. Somatic organogenesis from basal callus or other floral parts was most effective on the media containing 2,4-D. Plants obtained by gynogenesis were haploid in 70–77% and plants from somatic tissue were mostly diploid.

Parsley leaves (Petroselinum crispum) have long been known for their organoleptic properties. They are widely used in cuisine all over the world in fresh and dried form and also as pharmaceutical raw material. The presented work assessed if the storage of parsley leaves (as whole leaves or leave pieces) and packaging with PE or Xtend^® foils influence the content of selected chemical compounds and the microbiological quality of the product. For this purpose, the leaves were dried, packaged and analyzed after 3 weeks’ storage under room temperature. Neither the degree of fragmentation nor the type of packaging foil affected the content of vit. C and total sugars. Higher content of reducing sugars was obtained in the samples packed in PE foil. Number of detected bacteria did not exceed the safety border. Less bacterial colonies were detected in the material packed as fragmented in the PE foil. No fungal colonies were detected in the leaves packed in the Xtend^® foil.

In order to consider phosphorus (P) limitations in agriculture, research has been carried out on the methods that can improve plant growth and increase the efficiency of P use. A pot experiment was conducted to find the effects of magnetized Ca(H₂PO₄)₂·H₂O solutions as P source at concentrations 0, 5, 10, 20 and 40 mg·dm⁻³ and inoculation with arbuscular mycorrhizal fungi Diversispora versiformis on P use efficiency, growth and photosynthetic pigments in sweet basil. P solutions were treated with magnetic field of 110 mT at 3 dm³·min⁻¹ volumetric flow rate. The results indicated that the growth of basil plant, the number of leaf, leaf area, harvest index and chlorophyll a and b contents significantly increased in the result of fertilization with magnetized P solutions and mycorrhizal inoculation as compared to the control. The application of magnetized P solution at 10 mg P·dm⁻³ and inoculation of mycorrhizal fungi increased P use efficiency by 18.9% and 23.5%, respectively. Findings of the experiment clearly showed that the use of magnetization of P fertilizer and mycorrhization potentially represent natural ways of promoting growth, P status and chlorophyll content in sweet basil.

The aim of this study was to determine the influence of dipping in tap and hot water (53 or 55 °C) before storage and conditions during short-term storage: 4 days at 18–20 °C temperature or 7 days at 0 or 5 °C, on contents of total polyphenols, ascorbic acid, antiradical activity, and sensory quality of leaves of wild rocket (Diplotaxis tenuifolia L.). The highest sensory values, ascorbic acid contents, and antiradical activity were found in fresh leaves. Treatments with tap and hot water before storage reduced ascorbic acid contents and antiradical activity, as well as most sensory parameters regardless of storage conditions. The highest overall quality of wild rocket after storage for 4 days at 18–20 °C was found for leaves not dipped or dipped in tap water. Dipping of the wild rocket in the water at 53 or 55 °C for 3 or 5 s did not improve the overall quality of stored leaves compared with leaves not dipped or dipped in tap water.