Zeatin

About: Zeatin is a research topic. Over the lifetime, 2467 publications have been published within this topic receiving 64092 citations. The topic is also known as: Zeatin & (E/Z)-zeatin.

Postharvest dormancy-related changes of endogenous hormones in relation to different dormancy-breaking methods of potato (Solanum tuberosum L.) tubers

Abstract: Development of an efficient and eco-friendly technique to break tuber dormancy in potato (Solanum tuberosum L.) is highly demanded due to the production of two or more crops annually. Several physiological and hormonal changes have been found to be related to the breaking of tuber dormancy; however, their consistency with genotypes and different protocols have not been well clarified. This study aims to evaluate the effectiveness of four dormancy-breaking methods, that is, plant growth regulator (PGR) dipping in 30, 60, or 90 mgL−1 benzyl amino purine (BAP) and 10, 20, or 30 mgL−1 gibberellic acids (GA3) alone and in the combination of optimized concentrations; electric current application at 20, 40, 60, or 80 Vs; cold pre-treatment at 2, 4, or 6 °C; irradiation at 1, 1.5, 2, 2.5, 3, or 3.5 kGy. In addition, changes in endogenous levels of abscisic acid (ABA), zeatin (ZT), and gibberellin A1 (GA1) in six potato genotypes after subjecting to these methods were investigated. Overall, the highest effective method for dormancy duration was the PGR application which shortened the duration by 18 days, followed by electric current (13 days), cold pre-treatment (9 days), and then irradiation (7 days). The solution of 60 mgL−1 BAP significantly reduced the dormancy duration in all genotypes but did not have a significant effect on the sprout length. While 20 mgL−1 GA3 produced maximum sprout length with a non-significant effect on dormancy duration. The genotype × PGR interaction for dormancy duration was more pronounced in short- and medium-term dormancy genotypes than in long-term dormancy genotypes. The genotypes displayed a significant positive correlation between dormancy duration and ABA levels but exhibited a negative correlation between dormancy duration and ZT as well as GA1 levels. From the first to the third week of storage, ABA was decreased in tubers while, however, ZT and GA1 were increased. The obtained results could be useful for the postharvest storage of potato tuber and the related field of physiological investigation in future.

The Transformation System in Foxglove (Digitalis purpurea L.) Using Agrobacterium rhizogenes and Traits of the Regenerants

Abstract: Our final goal is to breed dwarf cultivars of foxglove (Digitalis purpurea L.) using Agrobacterium rhizogenes. For this aim, we examined an effective method for hairy root induction, the phytohormone condition for regeneration from the root and traits of the regenerants. In the case of using a filter paper soaked with 1/2MS liquid medium for co-cultivation of leaf pieces with the bacteria, 30-40 hairy roots per 100 pieces were expected to be induced. Higher effect was given for regeneration from the hairy root through callus in zeatin addition than with BA, kinetin and no phytohormone added. In potted plants, numerical values of plant height, number of leaves, spike length, number of florets and leaf size were lower in a strain of transformants than in non-transformants, and both types of the plants exhibited similar plant forms and leaf morphologies. These traits provide novel possibilities for the breeding of dwarf cultivars of foxglove.

Micropropagation, detection and elimination of DMV in the Czech collection of dahlia

Abstract: Production of virus free dahlia plants is necessary for the maintenance of the Czech collection of Dahlia pinnata. The effects of cytokinins (BA and zeatin) and time of sampling of primary explants were investigated. Higher regeneration rate of primary explants was observed when explants were grown on MS medium with 0.5 mg L -1 zeatin. Dahlia mosaic virus (DMV) could be eradicated from infected plants by meristem-tip culture. The effects of size of meristem tips on virus elimination and meristem regeneration were investigated. Apical meristems excised from in vitro culture of Dahlia were cultivated on MS medium with zeatin. Efficiency of meristem culture in elimination of DMV was 50% and 9% for plantlets developed from meristems in size 0.4-0.5 mm and 0.9-1 mm, respectively. Real-time PCR (polymerase chain reaction) and conventional PCR assay were used for detection of DMV.

Micropropagation of globe artichoke (cynara scolymus l.) from underground dormant

Abstract: Side shoots excised from underground dormant buds of Cynara scolymus L. were used as primary expiants to establish in vitro cultures. A 3 X 3 factorial experiment with all possible combinations of three concentrations (0.5, 1.0, 2.0 mg/ liter or 2.22, 4.44, 8.88 \iM) of 7V6-benzyladenine (BA) and three concentrations (0, 0.1, 0.2 mg/liter or 0, 0.54, 1.07 ujlf) of 1-naphthaleneacetic acid (NAA) was used to determine the optimum growth regulator combination for shoot multipli cation. The highest rate of axillary shoots was induced on Murashige and Skoog agar medium supplemented with 0 mg NAA/liter and 1.0 mg BA/liter (4.44 \iM). Other cytokinins tested (kinetin, zeatin, and 2-isopentenyl-adenine were less effective than BA in inducing axillary shoot growth. Up to 60% of elongated microshoots rooted after 5 weeks on 1/2 MS agar medium supplemented with 2 mg/liter (11.42 \xM) indole-3-acetic acid (IAA). Seventy percent of rooted plantlets were transferred successfully into soil. Plants are under evaluation for their genetic uniformity and clonal fidelity.

Micropropagation of Juvenile and Mature Tree of Corylopsis coreana by Axillary Bud Culture

Abstract: We have developed an in vitro micropropagation system via shoot formation from axillary buds using nodal segments of Corylopsis coreana. Explants from both juvenile tree (one-year-old greenhouse stock seedlings) and mature tree (ten-years-old tree in nursery) were compared with regard to propagation efficiency. Combined treatment of both BA and zeatin were effective on shoot proliferation since the best result was obtained on MS medium supplemented with 0.5∼3.0 mg/L zeatin and 0.2 mg/L BA. Generally, juvenile explants were better in both shoot proliferation and growth than mature explants. However, as the duration of in vitro culture was proceed to 6 months, explants from mature tree also produced three shoots per explant. Distinctive differences in rooting and adaptability to soil of shoots obtained from mother trees. Whereas shoots originated from juvenile explants rooted as high as 97%, those from adult explants showed 62% rooting. Similar result was also observed in soil acclimatization. The plantlets derived from juvenile plants survived 67%, while only 48% of those from adult trees survived. The results showed a possibility of the micropropagation of Corylopsis coreana through shoot formation from axillary buds. In addition, the advance of the research still remain to enhance the frequency of acclimatization of plantlets from mature trees for practical application.