Adelberg, Jeffrey

Gollagunta, Vani

Rajapakse, Nihal C

English

Clemson University: TigerPrints

Clemson UniversityTigerPrintsPublications Plant and Environmental Sciences2002In Vitro Storage of Hosta Micropropagules - Effectof Media Sucrose on Post-Storage RecoveryJeffrey AdelbergClemson University, jadlbrg@clemson.eduVani GollaguntaClemson UniversityNihal C. RajapakseClemson UniversityFollow this and additional works at: https://tigerprints.clemson.edu/ag_pubsPart of the Agriculture CommonsThis is brought to you for free and open access by the Plant and Environmental Sciences at TigerPrints. It has been accepted for inclusion inPublications by an authorized administrator of TigerPrints. For more information, please contact kokeefe@clemson.edu.Recommended CitationPlease use publisher's recommended citation.365SNA RESEARCH CONFERENCE - VOL. 47 - 2002In Vitro Storage of Hosta Micropropagules – Effect ofMedia Sucrose on Post-Storage RecoveryVani Gollagunta, Nihal C. Rajapakse andJeffrey W. AdelbergClemson University, Department of Horticulture,Clemson, SC 29634Index words: Sucrose-free Storage, Commercial Micropropagation,PhotoautotrophyNature of work: In vitro storage under growth retarding conditionsdelays the necessity for frequent transfers to fresh media and allowsflexibility in meeting market demand leading to efficient management oflabor. Storage conditions should preserve the post-storage quality andregrowth potential of in vitro plants. Wilson et al. (1998) reported that lowlight [photosynthetic photon flux (PPF) of 5-7 mmol m-2 s-1] in storageimproved post-storage quality and recovery potential of in vitro plantlets.In our research, increasing media sucrose to 5% or 7% during themultiplication phase (stage II) increased the internal sugar levels, biom-ass, and quality in Hosta micropropagules. When these cultures weretransferred to rooting phase (stage III) in a media containing 3% sucroseand subsequently stored for 5 weeks at 10¥  C, under a PPF of 5 mmolm-2 s-1, plantlets from the 5% or 7% sucrose media were of better qualitythan the plantlets from 1% or 3% sucrose (unpublished data). Datasuggests that sucrose loading during multiplication phase had positiveinfluence on post-storage plant quality (unpublished).Sugar-free micropropagation holds significance in commercialmicropropagation because sucrose-free medium reduces media contami-nation and consequent loss (Kozai, 1991). Therefore, the objective of thisinvestigation was to examine if sucrose loading during multiplicationphase allows in vitro rooting and storage in sucrose-free medium.This study was conducted with two cultivars of Hosta:  tokudamaTratt. ‘Newberry Gold’ and Hosta ‘Striptease’. Stage II Hosta budscultured in 5% media sucrose were procured from Southern Sun Propa-gation Systems, Norris, SC.  Plants were transferred to stage III forrooting (on sorbarod plugs) (Ilacon Industries, UK) in magenta boxes(Magenta Corp. Chicago IL) containing modified Murashige and Skoog(1962) liquid medium. During stage III plants were cultured in media with3% sucrose (photomixotrophic cultures) or without sucrose (photoau-totrophic cultures) for four weeks at 25+2 °C under a PPF of 150 mmolm-2s-1. Nine buds of ‘Newberry Gold’ were cultured in each culture vesselwhile six buds of ‘Striptease’ (due to larger bud size) were cultured per366SNA RESEARCH CONFERENCE - VOL. 47 - 2002vessel. Following Stage III, cultures were stored, in the same culturevessel with residual medium, for 7 or 14 weeks under 5 mmol m-2 s-1 at10° C, with and without a 2-week intermittent period of darkness duringthe final phase of storage to simulate shipping. Plantlets (four vesselsfrom each treatment) were harvested for dry weight at the end of stage III(prior to storage) and after storage. Post-storage plantlets, from fiveculture vessels of each treatment, were transferred (after removal ofnecrotic leaves) to 606-cell packs containing a commercial potting mix(Superfine germinating mix, Fafard, Anderson, SC) and grown under mistfor 4 weeks for acclimatization. After 4 weeks under the mist, mortality ofthe plantlets was recorded. Data were analyzed by ANOVA and treat-ment differences were separated using LSD at P = 0.05. Efficacy ofsucrose loading on sucrose-free storage was assessed by comparingpost storage survival and plant quality in both photoautotrophic andphotomixotrophic cultures.Results and Discussion: Presence of media sucrose led to significantlyhigher shoot and root biomass in both the cultivars at the end of stage III(Fig.1 A & B). In ‘Striptease’, the root biomass of photomixotrophiccultures increased by 70% during 7 weeks of storage, while inphotomixotrophic cultures under continuous illumination, the root biom-ass remained unchanged thereafter. But in ‘Striptease’ photomixotrophiccultures that were stored for 14 weeks dark period had a negativeinfluence on the root biomass (Fig 2A). However, in ‘Newberry Gold’, nochange in root biomass occurred during 7 weeks of storage but a signifi-cant root growth occurred between 7 and 14 weeks of storage (Fig 2B).Incidence of shoot apex necrosis was higher in photoautotrophic culturesof both the cultivars, consequently, reflected by poorer percentage ofsurvival in the greenhouse compared to the photomixotrophic plantlets(Table 1). Both photoautotrophic and photomixotrophic ‘Striptease’cultures stored for 7 or 14 weeks recovered in the greenhouse but qualityof photomixotrophic cultures were better than photoautotrophic cultures(data not shown). Photoautotrophic ‘Striptease’ cultures had a signifi-cantly greater percentage of mortality (about 25%) compared tophotomixotrophic cultures (0%) after 7 weeks of storage. Photoau-totrophic and photomixotrophic ‘Newberry Gold’ cultures stored for 7weeks recovered in the greenhouse but extending the storage duration to14 weeks led to further decline in the greenhouse survival of the photo-autotrophic plantlets reflected by high percentage of mortality (Table 1).Overall, sucrose-free medium during rooting and storage led to poorpost-storage recovery in both the cultivars, while extending storageduration led to further deterioration in ‘Newberry Gold’. Results indicatebetween-cultivar differences in rooting and post storage recovery;‘Striptease’ can survive better in photoautotrophic cultures than‘Newberry Gold’. Media sucrose during rooting stage and storage367SNA RESEARCH CONFERENCE - VOL. 47 - 2002contributed towards enhanced post storage survival, by offering nutri-tional support for improved rooting and maintenance of growing shootapex during storage.Significance to Industry: In vitro techniques are being increasinglyused in the large-scale production of uniform disease free propagationmaterial. Demand for propagation materials is often seasonal andtherefore production peaks strive to match demand peaks. Employingsufficient labor exclusively during production peaks is impractical,because micropropagation involves expensive trained labor. Developingtechniques for in vitro storage and subsequent shipping enables efficientutilization of labor, thereby, bringing down production cost in commercialmicropropagation. Our study demonstrates that supplementing mediawith sucrose improves rooting and provides sustenance through out lowtemperature storage, enabling prolonged storage, as well as ensuringenhanced post storage survival.Literature Cited:1. Wilson, S.B., K. Iwabuchi, N.C. Rajapakse, and R.E. Young. 1998.Responses of Broccoli seedlings to light quality during low-tempera-ture storage in vitro: II. Sugar content and photosynthetic ability.HortScience, Vol. 33:1258-12612. Kozai, T. 1991. Autotrophic micropropagation In: Bajaj Y.P.S (ed)Biotechnology in agriculture and forestry Vol.17. Hi-Tech andMicropropagation I. Springer, Berlin Heidelberg. 1991. pp.313-343.3. Murashige, T. and F. Skoog. 1962. A revised medium for rapid growthand bioassays with tobacco tissue cultures. Physiol. Plant. 15:473-497.368SNA RESEARCH CONFERENCE - VOL. 47 - 2002Figure 1. Shoot and root biomass per vessel in the photoautotrophic(no sucrose) and photomixotrophic (3% sucrose) cultures of Hosta‘Striptease’ (A) and Hosta tokudama Tratt. ‘Newberry Gold’ (B) at theend of stage III (prior to storage). Means + S.E. are shown369SNA RESEARCH CONFERENCE - VOL. 47 - 2002Figure 2. Post-storage root biomass in Hosta ‘Striptease’ (A) and Hostatokudama Tratt. ‘Newberry Gold’ (B). Cultures were transferred to rootingin photoautotrophic (no sucrose) or photomixotrophic (3% sucrose)media and subsequently taken to storage for 7 or 14 weeks at 10 oCunder 5 µmol m-2 s-1 of PPF with or without an intermittent dark periodduring storage. Means + S.E. are shownpmd:  photomixotrophic with 2-week dark periodpml:   photomixotrophic with no dark periodpad:   photoautotrophic  with 2-week dark periodpal:    photoautotrophic with no dark period370SNA RESEARCH CONFERENCE - VOL. 47 - 2002Table 1. Percentage of plantlet mortality in the photoautotrophic andphotomixotrophic cultures of H sta tokudama Tratt.‘Newberry Gold’ andHosta ‘Striptease’ following 4 weeks post-storage recovery in green-house. Means with the same letter are not significantly different withineach cultivar.% Post acclimatizationTreatments mortalityNewberry Gold Striptease7 weeks 14 weeks 7 weeks 14 weeksPhotomixotrophy with2-week dark period 0% c 2.2% c 0% b 20.8% abPhotomixotrophy withno dark period 0% c 0% c 0% b 10% abPhotoautotrophy  with2-week dark period 35.5% b 88.9% a 26.7% a 33.3% aPhotoautotrophy withno dark period 35.5% b 84.4% a 25.0% ab 20.0% ab

In Vitro Storage of Hosta Micropropagules - Effect of Media Sucrose on Post-Storage Recovery

https://tigerprints.clemson.edu/cgi/viewcontent.cgi?article=1019&amp;context=ag_pubs

In Vitro Storage of Hosta Micropropagules - Effect of Media Sucrose on Post-Storage Recovery

Abstract

Similar works

Full text

Available Versions

Clemson University: TigerPrints