Search
Search Results
-
Vegetative and micropropagation potential of Piper guineense (Schumach and Thonn)
29-36Views:447The continuous loss of forest plants due to deforestation, and the increasing demand for Piper guineense because of its medicinal and food value, has put a permanent pressure on its population in the wild where it is collected. A method for conservation and mass propagation is therefore required. This research was undertaken to determine the optimal concentration of auxin needed for vegetative propagation and to investigate the potential of Piper guineense for micropropagation. The auxin optimization study of vegetative propagation was based on the use of two-nodal stem cuttings treated with five different concentrations of indole-butyric acid (IBA). Growth parameters such as the number of sprouted, rooted and survived cuttings among others were determined. To investigate the potential of Piper guineense for micropropagation, nodal explants were subjected to different sterilizing treatments using ethanol, NaOCl, mancozeb, streptomycin and Plant Preservative Mixture (PPM). The effect of plant growth regulators (PGRs) was tested on sterilized nodal explants using full strength Murashige and Skoog (MS) hormone-free media alone as control and MS media supplemented with PGRs (BA, NAA and KIN) at different concentrations and combinations. Significant differences were observed across the treatments for all growth parameters measured. However, 2000 ppm IBA significantly (p<0.05) influenced sprouting and rooting of the stem cuttings. Piper guineense explants have deep tissue contaminants, which cannot be eradicated by surface sterilization alone except double sterilization using PPM. On control media, neither shoot nor root response was observed while the highest percentage of induced roots was obtained from explants cultured on MS +1 mg/L BA + 0.25 mg/L NAA. Shoot induction was only achieved when BA was used alone and when subcultured on media supplemented with NAA, which generated roots.
-
Introduction of alkanet (Alkanna tinctoria (L.) Tausch), a traditional dye plant into cultivation
41-46.Views:626As a part of the research project to establish natural sources of plant pigments, possibilities of introduction of Alkanna tinctoria (alkanet) into cultivation were studied.
As a result of the germination experiment, the relevance of 21 days' duration of germination procedure was proved. To get high germination rate alkanet fruits are proposed to pretreat by gibberellinic acid (GA3) in the concentration of 400 ppm, overnight before sowing. This method results approximately 50 % germination rate.
The morphological and production properties of alkanet roots are characterized during ontogenesis. Transplanted populations can be characterized by numerous, thick and heavy roots comparing to the spontaneous ones. Thus, seed sowing and transplantation proved to be an effective method for cultivation of the species.
According to our results it can be concluded that in cultivation the optimal harvesting time of roots is at the end of the second vegetation cycle, when the dry root mass of the individuals is about 10-20 g with 3,0-3,5 % accumulation level of active substances.
Considerable seasonal variability have been found influencing not only the root masses, but also the accumulation levels of alkannin derivatives. In a more humid vegetation cycle the root size and mass as well as the content of active substances are much higher.
-
Effects of aromatic cytokinins on structural characteristics of leaves and their post- effects on subsequent shoot regeneration from in vitro apple leaves of 'Royal Gala'
41-46.Views:465The effects of different aromatic cytokinins applied in different concentrations and combinations were investigated on the histology of in vitro apple leaves and their post-effects on subsequent shoot regeneration from these leaves were studied. Great differences in the anatomical structure of leaves could be detected originating from media containing different types and concentrations of aromatic cytokinins. The number of regenerated shoots per explant and the organogenetic index were used for the evaluation of the post-effect of aromatic cytokinins on shoot regeneration. The histological structure of leaves used for regeneration and their regeneration response showed a good correlation. When the pre-treatment caused a juvenile-like or less-differentiated structure, the number of regenerated shoots per explant increased and often vitrification also decreased and consequently the organogenetic index also increased. A strong interaction between cytokinin-content (type and concentration) of the pre-treatment medium and that of the regeneration medium could also be detected.
-
N:K ratio and its effect on paprika yield and quality in hydroculture
35-38.Views:347Earlier results of experiments with paprika grown in soil have shown the high sensitivity of the crop to nutrient supply. According to these findings, yield and also fruit quality are highly affected not only by the nitrogen and potassium level, the concentration of nutrient solution, but also by the nitrogen-potassium ratio. Our preliminary tests have also proved, that the composition of the nutrient solution, first of all, the N/K ratio has a definite effect on the yield quantity and quality. Therefore we have investigated the ratio of the two nutrients with the aim of developing a nutrient solution of optimal composition for white fruited paprika forcing. The most balanced burden of the plants was found when the N/K ratio was 1:1. The highest yield was produced with N/K 1:1.3. Significant yield reduction (30%) was found with the treatment N/K 1:1.9 as compared to the 1:1.3 and 1:1.6.
-
The effects of growth regulators in proliferation of Sorbus redliana 'Burokvölgy'
77-83.Views:406The Hungarian cultivar Sorbus redliana 'Burokvölgy' was proliferated on Murashige and Skoog (MS, 1962) medium with half-strength macroelements and 100 mg/1 meso-inositol, 20 g/1 sucrose, 11 g/1 agar-agar. Different combinations of kinetin (KIN), metatopolin (mT), benzyladenine (BA), benzyladenine-ribosid (BAR) and indolebutiric acid (IBA) were tested, and pH was adjusted to 5.6 every case using KOH. The cultures were incubated at 20-24 °C in 8/16 hours dark/light photoperiod for 50-52 days. The main aim of our research was to find the optimal growth regulator and its optimum concentration. Purthermore, to determine the chlorophyll contents of the in vitro propagated plants' leaves. During the proliferation, the highest number of shoots were observed in the case of using BA + IBA, and on the medium containing 0.75 mg/I BA + 0.05 mg/1 IBA 8.93 shoots were found. The addition of KIN + IBA decreased the number of shoots and increased the sizes of leaves — the widest (11.2 mm) and longest (17.8 mm) leaves were obtained on the medium containing 1.00 mg/I KIN + 0.05 mg/1 IBA. The longest shoots (36.46 mm) were found in the case of applying 0.75 mg/1 BAR + 0.05 mg/I IBA. The BA + KIN + IBA combination resulted the shortest shoots. Sometimes not only shoot regeneration but spontaneous rooting was observed during the multiplication. The highest chlorophyll content (1.569 mg/g total chlorophyll, 1.132 mg/g chlorophyll-a, 0.437 mg/g chlorophyll-b) was obtained in the presence of 1.0 mg/I KIN + 0.05 mg/1 IBA.
-
The effect of spring frosts on the nectar production and the bee visitation of fruit trees
86-89.Views:1107Fruit tree species suffered very strong spring frosts in 1997 in Hungary. This caused partial or total damages at buds and flowers depending on site and time of blooming. It was demonstrated at a number of experiments that frost and cold weather also strongly affected the nectar production of surviving flowers. No or very little amount of nectar was measured in flowers first of all of early blooming fruit tree species (apricot) but also of pear and apple in some places. In spite of this fact intensive honeybee visitation was detected in the flowers of fruit trees that suffered partial frost damage only at those sites where honeybee colonies were placed in or at the experimental plantations and the lack of sufficient amount of nectar did not affected bee behaviour seriously on fruit flowers. This means that bad nectar production failed to affect bee visitation of fruit trees definitely. The reason for this was the fact that not only fruit trees but another early bee plants (wild plants, too) suffered frost damage. Accordingly, in lack of forage bees intensively searched for food at blooming fruit trees with some living flowers. Consequently, there was an acceptable yield at those plantations where bud and flower damage was not complete. Accordingly, intensive bee visitation (that is moving additional bee colonies to overpopulate fruit orchards with honeybees) can be an effective tool to decrease or eliminate the detrimental effect of spring frost on the yield of fruit trees where bud or fruit damage is not too high.