Postharvest application of chitosan and Thymus essential oil increase quality of the table grape cv. ‘Shahroudi’

Purpose: Chitosan, a natural biopolymer with antifungal and eliciting properties is able to reduce postharvest decay of table grapes. Anti-fungal and anti-microbial effects of essential oils are the result of many compounds acting synergistically. In this study, the effectiveness of Thymus essential oil (TEO) and chitosan to control postharvest decay and quality of ‘Shahroudi’ table grape was investigated. Research Method: Grapes treated by 0.5% and 1% (w/v) solution of chitosan, 150 and 300 µl l-1 Thymus essential oil and their combination (untreated fruit were as control). At first chitosan solution prepared then Thymus essential oil was added it in combination solution. Harvested grapes were packed in 200g bags and stored at 0±2 ◦C and 90% ± 5 RH for 90 days. Findings: Differences in weight loss, color change, ripening, sensory quality and decay between grapes treated with chitosan and TEO and control fruit suggested that TEO and chitosan were both suitable coatings. Moreover, the sensory analyses revealed beneficial effects in terms of delaying rachis browning and dehydration and maintenance of the visual characteristics of the grape without detrimental effects on taste or flavors. Research limitations: It had no limitation to report. Originality/Value: TEO and chitosan might have good effects in reducing postharvest fungal rot and maintaining the quality of ‘Shahroudi’ table grapes which proved to be much more effective than TEO

A new protocol for direct regeneration of stevia plant (Stevia rebaudiana Bertoni) by tissue culture techniques

Purpose: Due to pharmaceutical value of Stevia plant (Stevia rebudiana Bertoni.), this study was done to introduce a new protocol for rapid mass propagation of itthrough tissue culture. Research Method: In MS medium shoot proliferation of stevia by six concentrations of BA (0, 0.1, 0.2, 0.3, 0.4, 0.5 mg·l-1) and root induction by four concentrations of IBA (0, 0.025, 0.05, 0.1 mg·l-1) was investigated.Rooting of cuttings was done both in vitro and ex vivo conditions. Findings: According to the results, the most number of stems obtained in MS medium containing 0.3 mg l-1 BA. The highest length of stems obtained in MS medium without BA and the most number of leaves observed in MS medium supplemented with 0.4 mg·l-1 BA. In in vitro situation, the most number and length of roots obtained in MS medium without IBA. The most number of rooted cuttings was obtained in IBA solution after 72 hours and about 70% of rooted cuttings were healthy. Research limitations: It had no limitation to report. Originality/value: In conclusion, it seems that the potential of producing root and shoots in stevia plant is extremely high, so its proliferation is possible using low concentrations of plant growth regulators in in vitro culture

Putrescine and IBA enhanced the adventitious root formation in Damask rose (Rosa × damascena Mill.) under in vivo and in vitro conditions

Purpose: To investigate the effects of Putrescine and Indole-3-Butyric Acid (IBA) on the adventitious rooting of micro-cuttings and semi-hardwood cutting of Rosa damascena, this study was conducted under both in vitro and in vivo conditions. Research Method: The rooting of micro-cuttings was induced on the basal MS medium supplemented with five concentrations (0, 0.25, 0.5, 1 and 2 mg/L) of IBA and putrescine.  In vivo experiment, putrescine and IBA at five concentrations (0, 0.25, 0.5, 1 and 2 g/L) were applied on semi-hardwood damask cuttings, while a downward wounding was created by a sharp blade on the bases of cutting as another treatment. Findings: Data showed significant variations in the root number and root length for in vitro and in vivo cuttings treated with different concentrations of putrescine and IBA. The obtained results revealed that presence of putrescine and IBA in both conditions enhanced root formation, as significantly improved the number of roots and root length in each explant. Under in vitro conditions, the maximum root length and root number were observed on the MS medium supplemented with 1 mg/l IBA+1 mg/l putrescine. Research limitations: No limitations were found. Originality/Value: The present study highlighted the role of putrescine and IBA in the adventitious rooting of R. damascena, under both in vitro and in vivo situations

Effect of different factors on micropropagation of Abarkooh 4000-year-old horizontal cypress (Cupressus sempervirens L. var. horizontalis (Mill.) Gord.)

This study was conducted to protect the genetic properties and propagation of 4000-year-old Abarkooh horizontal cypress (Cupressus semprvirens L. var. horizontalis (Mill.) Gord.) by tissue culture technique. In the first experiment, the effect of preparation time of explant (four seasons), medium culture (MS and WPM) and concentrations of BA (0, 0.1 and 1 mg/l) on proliferation of horizontal cypress explants was investigated. In second and third experiments the effect of culture media (MS and WPM), concentrations of BA (0, 0.1, 0.5 and 1 mg/l) was studied alone or in combination with 0.01 mg/l IBA and type of explant (primary or secondary shoots) in a factorial experiment and completely randomized design with three replications. In first experiment, the maximum shoots number was obtained from spring and summer explants that were cultured in MS and WPM culture media, respectively. In second experiment, the maximum number and length of shoots was obtained in WPM culture medium and secondary shoots. The highest length of shoots was found in first shoots cultured in WPM medium containing 0.1 and 0.5 mg/l BA, followed by primary shoots cultured in MS medium culture without BA. In the third experiment, the maximum number of shoots (3) was observed in secondary shoots by using WPM medium containing 0 mg/l BA + 0.01 mg/l IBA. Conclusively the best time of preparing explant, type of culture media and explant were found to be spring, WPM medium and secondary shoots, respectively

Pseudo-embryogenic structures in anther and isolated microspore cultures in vitro: a cautionary guide

This review describes sources of structures of non-microspore origin observed in anther and microspore cultures. Various characteristics of these structures may cause a wrong diagnosis of these structures as embryos or cell/tissue clusters of microspore origin. Here we suggest such structures to be named as pseudo-embryogenic structures. The introduction of pseudo-embryogenic structures and their origins could be helpful to distinguish them from true microspore-derived structures. Prompted by certain environmental cues, somatic cells existing as a contamination in immature pollen (microspores) cultures can lead to the formation of 'pseudo-embryos' commonly known as embryoids. The pseudo-embryogenic structures may be classified in the following groups: (i) pseudo-star-like structures; pseudo-multicellular structures; (ii) pseudo-embryos with pseudo-suspensors; (iii) contaminating bacteria appearing as callus colonies; (iv) calli and embryos of somatic origin; (v) giant tetrad-like structures; (vi) anther wall cells. The exact origin of these structures is discussed in this paper, and some recommendations are proposed in order to avoid misinterpretation.EUEuropean Commission [COOP-CT-2003-508210]A part of the results presented here was supported by the EU funded project HAPLOTECH COOP-CT-2003-508210

Pseudo-embryogenic Structures in Anther and Isolated Microspore Cultures in vitro: a Cautionary Guide

This review describes sources of structures of non-microspore origin observed in anther and microspore cultures. Various characteristics of these structures may cause a wrong diagnosis of these structures as embryos or cell/tissue clusters of microspore origin. Here we suggest such structures to be named as pseudo-embryogenic structures. The introduction of pseudo-embryogenic structures and their origins could be helpful to distinguish them from true microspore-derived structures. Prompted by certain environmental cues, somatic cells existing as a contamination in immature pollen (microspores) cultures can lead to the formation of 'pseudo-embryos' commonly known as embryoids. The pseudo-embryogenic structures may be classified in the following groups: (i) pseudo-star-like structures; pseudo-multicellular structures; (ii) pseudo-embryos with pseudo-suspensors; (iii) contaminating bacteria appearing as callus colonies; (iv) calli and embryos of somatic origin; (v) giant tetrad-like structures; (vi) anther wall cells. The exact origin of these structures is discussed in this paper, and some recommendations are proposed in order to avoid misinterpretation.EUEuropean Commission [COOP-CT-2003-508210]A part of the results presented here was supported by the EU funded project HAPLOTECH COOP-CT-2003-508210