THE USE OF PERLITE AS SUPPORT IN LIQUID MEDIA FOR THE IN VITRO ROOTING OF SOME HORTICULTURAL SPECIES

The experiments have been done with the following species: Rosa sp. (Fig.1), Iresine sp. (Fig.2), Sequoia sempervirens (Fig. 3), Rubus sp and Ribes nigrum (Fig.4). Nutritive medium: in the Magenta vessels perlite wass added (approx. 10 g) onto which liquid MS medium was added (approx. 100 ml) until it covered the perlite and the vessels were autoclaved for 20 minutes at 121 °C

THE INFLUENCE OF ZEATIN AND 2-ISOPENTENYLADENINE UPON THE IN VITRO MULTIPLICATION RATE OF THE HIGHBUSH BLUEBERRY (VACCINIUM CORYMBOSUM)

The research was carried out at Fruit Research Station Cluj in the plant tissue culture laboratory; the varieties taken into study were: Toro, Elliott and Hannah’s Choice. For blueberry culture Woody Plant Medium was used as basal medium and, as growth regulators, 2-Isopentenyladenine (5 mg/l) and Zeatin (1 mg/l) were used, added before media autoclavation. For each cultivar, 1-1.5 cm long microcuttings were inoculated into each vessel. 7 weeks after inoculation 5 vessels were randomly taken for each variety and the multiplication rate was the following - 2-Ip as well as zeatin can be successfully used as growth regulators for the in vitro culture of the highbush blueberry, especially for the varieties taken into study. - Zeatin strongly stimulates plant growth and considerably increases multiplication rate in Vaccinium corymbosum

Alternative Gelling Agents for the Micropropagation of Some Horticultural Species

The research was done in order to test the possibility of using some gelling agents for the nutritive media which should be less costly than agar, for the micropropagation of some horticultural species (Jain, 2005). The multiplication cycle was of 2 months. 820 ml jars were used as culture vessels. Tab. 1 presents the gelling agent, the species used in the experiment, the variants of nutritive media and the resulting multiplication rates. The species that were studied presented multiplication rates similar to the ones in agar-gelled media and the plants were vigorous

Studies Regarding the Micropropagation of Some Blackberry Cultivars

Our paper presents the results of the application of a micropropagation protocol developed at theFruit Research Station Cluj, in Rubus fruticosus cultivars ‘ČaÄanska bestrna’, ‘Chester Thornless’, ‘LochNess’ and ‘Navaho’. For the in vitro multiplication stage, Murashige & Skoog (MS) media supplementedwith 0.3 and 0.5 mg/l BAP and gelled with starch were used. Direct ex vitro rooting was carried out.The shoots regenerated in vitro in the multiplication stage were rooted ex vitro in two experimentaltreatments: float hydroculture and floating perlite beds. In cultivars ‘Loch Ness’ and ‘Chester’ 0.5 mg/lBAP yielded good results regarding in vitro proliferation and multiplication rates and the regeneratedshoots were vigorous, suitable for ex vitro rooting and acclimatization. In cultivars ‘Navaho’ and ‘ČaÄanskaBestrna’ the optimal BAP concentration was 0.3 mg/l, which ensured normal plantlet development. Theexperimental treatments with 3 and 4 microcuttings / vessel gave good results, whereas the ones with 1and 2 microcuttings / vessel did not yield satisfactory results regarding growth and proliferation. Wheatstarch was successfully used as a gelling agent in all the cultivars. In cultivar ‘ČaÄanska bestrna’ potatostarch gave very good results regarding in vitro proliferation. In the direct ex vitro rooting experimentsfloating perlite gave good results in all the cultivars. In cultivar ‘ČaÄanska bestrna’ ex vitro rooting in floathydroculture gave relatively poor results, with rooting percentages around 60 %

THE INFLUENCE OF THE GELLING AGENT UPON MULTIPLICATION RATE IN SEQUOIA SEMPERVIRENS

This paper presents the influence of the gelling agents upon the multiplication rate of Sequoia sempervirens. Three variants of media were used (Table 1), respectively, hormone-free MS gelled with 5 g/l Plant-agar, 2 g/l Gelrite and 100 g/l perlite added as mechanical support before autoclavation. The best multiplication rate was obtained on the variant with 2 g/l Gelrite

PROLONGING THE IN VITRO CULTURE MAINTEINANCE PERIOD IN SOME HORTICULTURAL SPECIES

The aim of our research was to prolong the in vitro culture period in species Haworthia cymbiformis, Exacum affine and Drosera rotundifolia. For Drosera rotundifolia two layers of media were used, both hormone-free MS. The liquid medium was poured over the plants that have been grown in agar gelled media for two months. The resulting plantlets have been counted and weighed after nine more months of in vitro culture. For Exacum affine 3 experimental v

THE EFFECT OF BENZYLADENINE UPON EXACUM AFFINE IN VITRO

Shoot fragments containing 2 nodes taken from plants cultured on hormone-free MS medium were inoculated onto modified MS media supplemented with 1 mg/l vitamin B1 and the following concentrations of the cytokinin benzyladenine: 0, 0.5, 1 and 2 mg/l, 2 Magenta GA7 vessels/variant, 5 microcuttings/vessel. The shoots were inoculated in vertical position, with the basal node in the medium and the apical one out of the medium. After 2 months in culture the following average number of shoots per plantlet were obtained (Fig. 1): Only the shoots at least 5 mm in length were considered. In the variants with 1 and 2 mg/l there were also masses of buds and very short, deformed shoots, especially in the variant with 2 mg/l BAP, in this one the material not being suitable for further propagation. In the variant with 0 mg/l BAP the shoots were robust and long, with long, healthy roots. The variant with 0.5 mg/l BAP also yealded robust shoots, being the optimal variant from the point of view of multiplication rate and the quality of plants. 1 mg/l BAP was the maximum concentration that proved to be suitable for the micropropagation of Exacum affine (Fig. 2). We recommend the use of either hormone-free MS medium or medium containing 0.5 mg/l BAP for the micropropagation of Exacum affin

THE IN VITRO PROPAGATION OF THE RASPBERRY

This paper presents aspects regarding the in vitro propagation of the yellow raspberry cultivar Citria. For culture initiation, two variants of media were used, both having Murashige-Skoog (MS) (1962) as basal medium and, as growth regulators, 1 mg/l 6-benzylaminopurine for variant 1 and 2 mg/l Zeatin for variant 2. In order to establish the optimal medium from the point of view of multiplication rate as well as from an economical point of view, experiments were done with 3 variants of media, variants 1 and 2 had, as basal medium MS salts, Myo inositol-100 mg/l, Vitamin B1- 1 mg/l, Vitamin B6 - 0.5 mg/l, Nicotinic Acid - 0.5 mg/l, FeNaEDTA stock solution- 5ml/l, and variant 3 had, as basal medium, Woody Plant Medium (WPM) salts, Myo-inositol-100 mg/l, Vitamin B1- 2 mg/l, Vitamin B6 - 1 mg/l, Nicotinic Acid - 1 mg/l, Sequestrene 138- 100mg/l. As growth regulators, 0.7 mg/l BAP was used in variant 1, 0.1 mg/l TDZ in variant 2 and 1 mg/l Zeatin in variant 3. All variants had commercial crystal sugar as carbon source and Plant Agar as gelling agent, pH was adjusted to 5.7 for variants 1 and 2 and 5 for variant 3