Search Results
Large numbers of genetically stable, homozygous plants are needed for classical and molecular breeding programmes. In vitro anther culture has proved to be a useful tool for haploid/doubled haploid (DH) induction in pepper (Capsicum annuum L.) for more than twenty years. The present paper reports on a great improvement in the in vitro haploid induction and genome duplication methods routinely used for resistance breeding in sweet and spice peppers by two Hungarian research institutions, the Agricultural Biotechnology Center in Gödöllő and the Budapest Research Unit of the Vegetable Crops Research Institute. As a result of the colchicine-stimulated early genome induction method, the critically low (<0.1%) regeneration frequency of spice pepper types became ten times greater, reaching a value of around 1.0%, though this was still considerably lower than that achieved in pepper varieties for fresh consumption (5-10%). Moreover, the ratio of useful doubled haploids was far higher (H:DH = 1:2 or 1:4) in some cases after colchicine treatment than that of untreated control plants (H:DH = 2:1 or 3:1, depending on the genotype). An efficient method with good reproducibility, requiring less manual work, was elaborated for the in vitro genome duplication of pepper haploid regenerants using colchicine. When the haploid induction ability of plants conventionally cultured in the greenhouse was compared to that of plants raised under artificial conditions in phytotron chambers (satisfactory day and night temperatures, illumination, humidity), the responsiveness of the latter microspores (ratio of plant regeneration) was found to be almost twice as high. The application of 3% maltose for six days at 35°C resulted in a 1.45% increase in the ratio of responding anthers and a 0.34% increase in plant regeneration, averaged over all the variety types. Phenosafranin staining was used for the analysis of microspore viability. The reduction in viability during the induction period proved to be less pronounced in lines with better androgenetic responses than in those with poorer responsiveness.
5 Ernandes, J., Williams, J., Russell, I., Stewart, G. (1995) Effect of yeast adaptation to maltose utilization on sugar uptake during the fermentation of brewer's wort. J. Instit. 99 , 67
The use of mature embryos as explants to initiate cultures is a best alternative to save time and costs, especially for producing somatic embryos for genetic transformation of durum wheat. However, plantlets regeneration from cultures derived from matured embryos is usually low. In this study, we tested matured embryos as explants from eight Moroccan durum wheat varieties (‘Irden’, ‘Marzak’, ‘Kyperounda’, ‘Isly’, ‘Amria’, ‘Karim’, ‘Marouane’ and ‘Tomouh’) to define suitable culture media for obtaining high frequencies of somatic embryogenesis and in vitro plantlets regeneration. For this purpose, we tested five induction and maintenance media (M1 to M5) based on MS media (macro and oligo-elements) which differed with respect to concentrations of plant hormones (2,4-D and BA), vitamins, sucrose, maltose, L-asparagine, and solidifying agents. All tested media induced embryogenic callus for the varieties and regenerate plantlets. However, a significant effect of variety, medium and variety × medium interaction were observed for callus induction and regeneration. Average callus growth as measured by relative fresh weight growth rate (RFWGR) across different media was the highest for ‘Amria’ (7215.4%) and the lowest for ‘Tomouh’ (2088.2%). M1 (2 mg/L 2,4-D) and M5 (3 mg/L 2,4-D) media gave highest RFWGR(6892.1% and 6332%, respectively) and M3 (1 mg/L 2,4-D) was the lowest (3708.8%), across different varieties. However, the embryogenic callus from M3 media regenerated the highest percentage of plantlet, upon transfer to regeneration medium, for most of the varieties. For the varieties ‘Marouane’, ‘Kyperounda’, ‘Marzak’, ‘Karim’, and ‘Tomouh’, the favourable medium was M3, whereas, for ‘Isly’, ‘Irden’ and ‘Amria’, both M2 (2.5 mg/L BA and 2.5 mg/L 2,4-D) and M3 were the favourable media for embryogenic callus induction. In this study, for the first time, favourable media for induction and regeneration from mature embryo of Moroccan durum wheat varieties were identified. These media will be used for callus induction and genetic transformation.
207 213 Patent, Highly Purified Maltitol Preparation Method, Japanese Patent J-01273593, 01.11.89. (1989). Patent, Maltose and Maltitol Preparation Method
and maltose concentration on in vitro androgenesis of hexaploid winter triticale and wheat. Plant Cell Tiss. Org. Cult. 39 :49–53. Hayes P.M. Effect of induction medium pH
Tiwari, S., Rahimbaves, I. (1992): Comparison of glucose, sucrose and maltose for Hordeum vulgare L. isolated microspore culture using different methods. Indian J. Exp. Biol. , 30 , 624
-fructose, maltodextrin, and maltose; Sigma–Aldrich, USA) was used for biofilm assay. A modified version of the previously described method ( O'Toole et al., 1999 ) was used to test biofilm formation. Fifty µL of bacterial suspension (McFarland standard 1
, W. J. (1969) Enzymatic determination of glucose in the presence of maltose. Anal. Biochem. 30 , 467-470. Enzymatic determination of glucose in the presence of maltose Anal. Biochem
Combe, N. B. and Smith, R. H. (1974): Digestion and absorption of starch, maltose and lactose by the preruminant calf. Br. J. Nutr. 31 , 227-235. Digestion and absorption of starch, maltose and lactose by the preruminant calf
small molecular weight carbohydrates (including FODMAPs) based on Muir et al. (2009) with minor modifications. Monomers and sugar alcohols were separated by a ligand exchange column (a). The DP2-DP4 oligomers (sucrose, maltose, trehalose, kestose
