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Pumpkin, squash and zucchini are important vegetable crops in tropical and temperate regions. The development of genetic transformation methods offers the potential of introducing valuable traits into these crops. An efficient in vitro plant regeneration system is a critical point for genetic manipulation. The regeneration ability of three Cucurbita varieties was tested on Murashige and Skoog medium supplemented with different growth regulators. Cotyledons of all the varieties were cultured to investigate the effect of 2,4-D (0, 1, 2, 3, 4 mg l −1 ) with or without KIN (0, 0.5, 5 mg l −1 ) and of BA (0, 1, 1.2 mg l −1 ) combined with IAA (0, 0.9, 1, 1.2 mg l −1 ), on the efficiency of shoot induction. Abscisic acid (0.26 mg l −1 ABA) was also added to one medium. To find the most suitable combination for shoot induction, cotyledon segments of the three varieties were also cultivated on media with different concentrations of BA (0–1.2 mg l −1 ) and IAA (0–0.9 mg l −1 ). Shoot induction was achieved via organogenesis in the tested varieties. Leafy shoots were transferred to root induction media. Regenerated plantlets with roots were transferred to sterile soil. This is the first report on in vitro regeneration from cotyledon explants of the pumpkin cultivar Nagydobosi and the pattypan squash cultivar Óvári fehér.
Studies on plant development phases and yield component patterns of wheat are essential for a better understanding of adaptation in wheat. Our main aim was to carry out detailed phenological analyses of 18 wheat genotypes in three sowing times for determining the effect of sowing date on individual phenophases, and yield components. Sowing date had the single greatest effect on the start of intensive stem elongation. The longer vegetation period had a favourable effect on main spike length and on the spikelet number per spike, but had no influence on thousand-kernel weight and grain number per spike. The time between the first node appearance and start of intensive stem elongation had a significant effect on the number of reproductive tillers. A close association (R2 = 0.191) was observed during the second phase of intensive stem elongation between the boot stage-to-heading interval and the number of spikelets per spike. Two-way analysis of variance on the yield components showed that the sowing date, as a main factor, had a weaker effect on the phenophases than on morphological and developmental parameters. The insensitive allele of the Ppd-D1 gene shortened the time required for first node appearance and heading both in autumn and spring sowing.
Species-specific PCR assay was used for the identification of Hungarian Fusarium graminearum isolates in pure mycelial culture. The Fg16F/Fg16R primer pair of the three known species-specific primers appeared to be the most appropriate one to identify F. graminearum .Two methods were used for comparative determination of the amplicon size of F. graminearum strains: traditional agarose gel electrophoresis, and chip electrophoresis. Our results have shown that the chip electrophoresis is an easy-to-use, time-efficient substitute for conventional agarose gel electrophoresis; moreover it provides a more precise size determination of amplicons. Amplicon size ranging from 415 bp to 421 bp in tested isolates may be associated with genetic diversity in the Hungarian population of F. graminearum .The PCR assay described in this study can be used for the routine detection and identification of F. graminearum without isolation and morphological investigation of this fungus.
Stress tolerance is associated with the activation of antioxidant compounds and enzyme systems that are capable of neutralising the reactive oxygen species (ROS) continually produced in response to stress. The present experiment was designed to compare the heat tolerance of four winter wheat varieties in the shooting and grain-filling stages by investigating changes detected in antioxidant enzyme activity and yield components in response to heat stress.Heat treatment was found to cause a significant rise in the activity of the glutathione-S-transferase and catalase enzymes, while there was usually a less intense decline in the activity of guaiacol peroxidase.An analysis of yield data revealed that heat stress had a more pronounced effect during grain filling in this experiment than at the beginning of shooting, as shown by the greater reduction in thousand-kernel weight and yield.
The aim of this paper was to find possible link between molecular and morphological similarities of 38 Hungarian white grape varieties. Three aspects of morphological and molecular similarity were assessed in the study: comparison of the ordered variety pairs, assessment of molecular and morphological mean similarity differences and separation of varieties into similar groups by divisive cluster analysis to define (DIANA). Molecular similarity was calculated from binary data based on allele sizes obtained in DNA analysis. DNA fingerprints were determined at 9 SSR loci recommended by the European GrapeGen06 project. Morphological similarity was calculated on the basis of quantitative morphological descriptors. Morphological and molecular similarity values were ordered and categorized after pairwise comparison. Overall correlation was found to be weak but case by case assessment of the variety pairs confirmed some coincidence of molecular and morphological similarity. General similarity position of each variety was characterized by Mean Similarity Index (MSI). It was calculated as the mean of n-1 pair similarity values of the variety concerned. Varieties were ordered and compared by the difference of the index. Five varieties had low morphological and high molecular MSI meaning that they share several SSR marker alleles with the others but seems relatively distinct according to the expression of their morphological traits. Divisive cluster analysis was carried out to find similar groups. Eight and twelve cluster solutions proved to be sufficient to distinct varieties. Morphological and molecular similarity groups partly coincided according to the results. Several clusters reflected parent offspring relations but molecular clustering gave more realistic results concerning pedigree.
In the present study, heat treatment was carried out in five different phenological phases, from the first node detectable (DEV31) growth stage to 20 days after flowering, on four wheat genotypes with very different adaptation strategies. They were grown in a controlled environment in a phytotron chamber and exposed to a night temperature of 20°C and a day temperature of either 30°C, at DEV31, or 35°C at all the later developmental phases, for an interval of 14 days. Plant height, leaf number, number of tillers, grain number and grain weight per main and side spikes, TKW per main and side spikes, length of the main and side spikes, and spikelet number per main and side spikes were recorded. High temperature enhanced the stem growth intensity, plant height and tiller number. In contrast, the length of side spikes, spikelet no./side spike, grain no./main and side spike, grain weight/main and side spike and TKW/main and side spike were significantly decreased. The stress response depended strongly on the developmental phase in which the heat stress was applied. Fleischmann 481 and Soissons showed definitely contrasting tendencies both in grain number and grain weight. In the case of the Plainsman V and Mv Magma pair, the higher heat stress tolerance of Magma compared to Plainsman V was evident also from the grain number and weight of the main spike at each developmental phase.
Abstract
To our knowledge, there is a lack of information on the nutrient composition of Busha cattle milk with special regard to its amino acid and biogenic amine contents. The Busha cattle breed is known to be highly resistant to various diseases and well-adapted to the extensive breeding conditions of the Balkan Peninsula. Busha cow milk contains an average of 13.47% dry matter, 4.34% fat, 3.72 % protein, and 4.32% lactose. Significant differences were detected (P < 0.05) in the amino acid compositions of the milk of different Busha cattle strains of Kosovo. Glutamic acid, proline, leucine, aspartic acid, lysine, and valine represented 68% of the total amino acid content. Essential amino acids, branched-chain and sulphur-containing amino acids were found in substantial amounts in the milk samples. Among the biogenic amines, however, spermine (0.16 mg kg−1) and cadaverine (0.09 mg kg−1) were present in low concentrations. Due to these excellent qualities of the Busha cow milk, preservation of this cattle breed is of great importance. Developing sustainable and secured breeding and feeding programs for this endangered cattle breed of the Balkan Peninsula should also be a high priority.
