Authors:Á. Richweisz, M. Z. Németh, L. Kiss, and T. Érsek
In December 2012 then in the following winter season, the occurrence of whitish mycelial coat was observed on the collar of 3- to 6-m high Bucida buceras trees grown in hydrocultures to decorate a spacious indoor community space in Vienna. (This plant [shown in Fig. 1] belongs to Combretaceae, Myrtales and commonly named black olive tree, bullet tree, gregorywood and oxhorn bucida.) The mycelium-infested area of the bark appeared to be water-soaked. Near the surface of the potting mix (earth ball embedded in clay pebbles), the roots were also covered with whitish mycelia (Fig. 2). Over the winter season when the indoor temperature increased from 20 °C to 25 °C, these symptoms were unnoticeable. Regardless of the season, the rhizosphere contained numbers of sclerotia, dark-grey, globose and 8–12 mm in diameter that occasionally developed rhizomorph-like mycelial cords.
Direct plating of mycelium fragments from the bark and sclerotia from the rhizosphere onto potato dextrose agar amended with ampicillin (500 mg/l) eventually yielded pure fungal cultures of similar characteristics. Cultures routinely incubated in the dark developed white and submerged colonies with sparse aerial mycelia. The fungus grew well between 10 °C and 25 °C, and failed to grow at either 5 °C or 32 °C. The optimal growth was measured at 20 °C with an average radial growth rate of 11 mm per day. After 10 to 12 days, a ring of sclerotia begun to develop near the edge of the colonies; they turned dark grey and sized 3–8 mm. Rather misleadingly, neither conidia, nor sexual spores were observed in these cultures. However, when the fungus was cultured in natural light under laboratory conditions at 25 °C, a completely different colony pattern was observed; it was cottony, greyish then dark grey, and produced abundant hyaline conidia borne on grey, branching tree-like conidiophores. Conidia were one-celled and egg-shaped, and their dimensions fell in the range of 9.89–14.63 (11.48±0.31) µm×7.05–10.05 (8.31±0.20) µm. These features concurred with those characterising the polyphagous grey mould fungus Botryotinia fuckeliana (anamorph: Botrytis cinerea) (Elad et al., 2007). The ITS1/ITS2 including the 5.8S subunit of rDNA of one of the isolates were amplified with primers ITS1-F/ITS4, then the PCR products were sequenced. The ITS sequence determined in this way was identical to known sequences of B. fuckeliana strains, e.g. that of CBS 131.28 (GenBank accession number: KF859918), the type material of Botrytis cinerea f. lini, DAOM 231372 (GenBank accession number: KF859924) and so on.
Pathogenicity tests resulted in rapidly (within 2 weeks) developing disease symptoms around the site of wound inoculation with a 5-mm-diametre mycelial agar plug: fruit rot on apple and lemon in the laboratory, and sunken lesions on stems of hydrocultured ornamental plants such as the herbaceous Monstera deliciosa and the woody Dracena marginata. To fulfill Koch’s postulates, the fungus was re-isolated from symptomatic apple fruit, and was found to exhibit the afore-mentioned morpho-physiological characteristics.
Inoculation test on Bucida was not performed because of the costly risk i.e., the sale price of the trees is € 3 to 10 thousand. Consequently, the actual sensitivity of Bucida to grey mould remains uncertain, so much the more because this plant species has not been recorded as a host of the pathogen or other important parasitic fungi in natural (subtropical) environment (e.g. Whelburg et al., 1975). To our knowledge, this report is the first description of Botryotinia fuckeliana on Bucida buceras. In addition to the fact that periodic emergence of fungal mycelia on the trunk impairs the tree’s aesthetic appearance, the sclerotia resting in the potting mix may cause more serious problems in the long term. However, it cannot be precluded that the elevated indoor temperature reduces disease progression and thus the economic importance of the pathogen on this plant.
Authors:T. Ljubka, Á. Lovas-Kiss, A. Takács, and A. Molnár V.
Epipactis albensis Nováková et Rydlo (Orchidaceae), a species previously undocumented in the flora of Ukraine, was found in three localities in this country (in vicinity of Chetfalva, Fanchykovo and Drotyntsi, Zakarpattia district) in 2012. The species (originally described from the Czech Republic) recently has only been known to exist in seven Central European countries. The three Ukrainian populations described here stretch within the floodplain of river Tisza. Based on measurements in 14 localities in Hungary, Ukraine and Romania the species has a considerably wide soil reaction tolerance (from 3.6 to 7.2 pHKCl). The fruit set of this strictly autogamous species is reasonably high (78%). The mean±SD thousand seed weight of the species was 0.0030±0.0005 grams, therefore E. albenis is classified into the hypermeichor seed-weight class. Recent discoveries of the species in Romania and Ukraine raise the possibility of its occurrence in further European countries.
Benthic diatom investigations of some Hungarian streams have been carried out in order to find reference sites in assistance to the ecological quality analysis of the different river types according to the Hungarian river typology. On the basis of the coevaluation of biological and chemical parameters, among the investigated streams, some part of Kemence stream seems to be the appropriate reference site for the classification of the highland, siliceous rivers of Hungary. However, further invastigations are needed for the selection of reference sites for the other types of Hungarian river typology. This is the most difficult in the case of lowland rivers, which are exposed to more severe anthropogenic impacts. Important is the question which biological parameters should be investigated and considered when assessing the ecological condition of our waters. In the United States, e.g. the assessment of the relative abundance of Achnanthidium minutissimum is quite widespread (Stevenson and Bahls 1999), the extent of which indicates the level of disturbance. The use of this method is hampered, on one hand, by the fact that A. minutissimum is an early coloniser species which means that if we do not take samples from mature periphyton, we might find it dominant simply because of that, and, on the other hand, that distinguishing between the species varieties is not always unambiguous under light microscope because of its small size, and these can have different ecological needs. It is also recommended to calculate species richness, diversity and evenness (Stevenson and Bahls 1999), but based on our investigations these parameters are not in correlation with water quality. Investigation of other diatom features such as tolerance and sensitivity, some autecological parameters (as it was applied and recommended by Fore and Grafe 2002 for investigating the reaction of diatom associations to anthropogenic disturbances) might also be useful in completing the water quality analysis of rivers, however, these methods need further investigations. Some of the indices (EPI-D, IPS, IBD) calculated with the software Omnidia are suitable for the classification of our rivers, but the investigation of more rivers, flowing through different types of stone are necessary to choose the appropriate indices. The reason for this is that the different indices work with a different register of species and obviously those indices will prove to be suitable the species register of which shows the highest similarity to the diatom associations of the certain water type.
Authors:L. Ş. Péterfi, L. Momeu, K. T. Kiss, and É. Ács
Plankton samples collected from a yellow watered bog pool of the mesotrophic “Călăţele Pădurii” peat bog (Romanian Western Mountains, Transylvania), exhibited an outstandingly rich Mallomonas population. The observations carried out by light and scanning electron microscopy revealed that the population belongs to Mallomonas intermedia Kisselev. Based on the presence of lance head bristles, distributed all over the cell armour (except few anterior collar, unilaterally serrated ones), it became evident that the population belong to the nominate variety (var. intermedia). Mallomonas intermedia var. saliceaensis formerly described from Transylvania differs by the type variety by the presence of exclusively serrated bristles. The present finding proved that Mallomonas intermedia could not be properly identified at infraspecific level solely based on the ultra structure of scales, without knowing the structure of bristles, too.
Authors:J. Komáromi, J. Kiss, T. Tuska, and B. Pai
Since first detected (Ba∞a, 1993), the western corn rootworm has become one of the
main pests of maize in Central Europe. CSALOMON® pheromone traps (sticky panel-LEM, cloak-PAL, etc., Plant
Protection Institute, Hungarian Academy of Sciences, Budapest, Hungary) are
recommended mainly for detection of western corn rootworm (WCR) (Tóth et al., 2003). In the USA at economic WCR population
levels, for field risk assessment, visual yellow sticky (Multigard, Pherocon
AM) traps are used. In a region where WCR population has been present only for
few years yet and the population increase proceeds, both trap types may be
suitable. In order to estimate the correlation between the captures of visual
and CSALOMON® pheromone traps, experiments were conducted for three years
(1998-2000) to find out whether a useful correlation exists
between captures on these two traps. Moderately strong and strong (minimum
R=0,77; maximum R=0,87) correlation was found between captures on Multigard and
CSALOMON® pheromone traps. At this population level no correlation
was found between capture on Multigard traps and next year's adult emergence.
Authors:T. Kiss, K. Balla, J. Bányai, O. Veisz, and I. Karsai
The yield potential of wheat depends not only on genetic × environmental interactions, but also on various agronomic factors such as sowing date or the seed rate used for sowing. The main aim of this work was to determine possible correlations between the effects of different sowing dates and plant densities on the yield components of a collection of 48 wheat genotypes. Two-way analysis of variance on the data revealed that both sowing date and plant density, as main components, only had a minor effect on the yield component patterns. Correlation analysis, however, indicated that the sowing date had a greater effect on the yield components, while plant density was in closer correlation with the heading time (r = 0.90). The patterns determined for individual yield components at two different sowing dates and plant densities showed significant differences for spike length, spike fertility, grain number in the main spike, number of productive tillers, grain number on side tillers, mean grain number and grain weight. Genotypes that carry the winter (recessive) alleles of genes regulating vernalisation processes (VRN-A1, VRN-B1, VRN-D1) and the sensitive (recessive) alleles of the two genes responsible for photoperiod sensitivity (PPD-B1, PPD-D1) may have better tillering and consequently higher grain yield, though this may depend greatly on the year.
Authors:T. Kiss, K. Balla, J. Bányai, O. Veisz, and I. Karsai
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.
Authors:K. Papp, É. Kocsárdy, A. Kiss, and T. Lakatos
The effect of reduction of pressure on the shapes of the TG, DTG and DTA curves and the mass-spectra of hydroxide and carbonate phases was investigated in some typical Hungarian red muds. The pressure change caused different decomposition rates of the phases and resulted in better separation of the overlapping thermal curves; this led to advantages as regards phase analysis. For phase analysis the red muds were extracted with water, and the extracts and solid residues were identified by IR- and X-ray methods.