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The damage caused by root-knot nematodes (Meloidogynidae) (irregular galls of different sizes on the plant roots) is a general problem in greenhouses in Hungary.The effect of Trifender microbiological preparation has been investigated on the degree of damage caused by root-knot nematodes in green-house pepper. We set up our experiment in Pusztamonostor (Jászság region, Hungary) in a family farm in 2008 and 2009. We carried out preliminary evaluation (Zeck-scale; 0–10) in the precrop with symptomatic assessment. According to the preliminary evaluation, the infection showed rates of 2–3 on the average.The results of 2008 show that Trifender had no effect on the number of females, but the plant height has been increased by 12 and 15%, and yield has grown by 25–35%. But on the contrary, in 2009 the number of females was decreased by 33%, and plant height was increased by 11%.
Microvascular function has been assessed by determining the rhythmic oscillations in blood flow induced by the vasomotion of resistance vessels. Although laser-Doppler flowmetry (LDF) allows simple, non-invasive evaluation of this flow-motion in the cutaneous microcirculation, the temporal and spatial reproducibility of such assessments remains unclear.
In the present study, we investigated cutaneous flow-motion in three consecutive years in eight skin regions using LDF in six healthy young volunteers. The characteristic flow-motion frequency was determined using fast-Fourier transformation. Additionally, in two years a more traditional measure of microvascular reactivity, postocclusive reactive hyperemia (PORH) was evoked in the forearm after transient brachial artery occlusion (1–2–3 min) induced by cuff inflation.
Well-defined flow-motion was found in six regions showing significant differences in frequency: the highest flow-motion frequency was found in the frontal and temporal regions (8.0 ± 1.1 and 8.5 ± 1.0 cycles/min, cpm, respectively, mean ± SD) followed by the scapular, infraclavicular and coxal regions (7.5 ± 1.3; 6.7 ± 1.1 and 6.5 ± 1.2 cpm, respectively). The lowest, stable flow-motion was found in the posterior femoral region (5.5 ± 1.0 cpm), whereas flow-motion was detectable only sporadically in the limbs. The region-dependent flow-motion frequencies were very stable within individuals either between the body sides, or among the three measurements, only the infraclavicular region showed a small difference (114 ± 17%∗, % of value in 1st year; ∗P < 0.05). However, PORH indices differed after 2–3 min occlusions significantly in consecutive years.
We report that flow-motion frequencies determined from LDF signals show both region-specificity and excellent intra-individual temporal and spatial reproducibility suggesting their usefulness for non-invasive follow-up of microvascular reactivity.
We investigated alfalfa and stinging nettle from the point of view of their potential to supply natural enemies of pests for protecting greenhouse cultures. We carried out a three year long study based on sweepnetting. The most frequent predatory insect was Orius niger (Wolff) in alfalfa and nettle. This species among others has an important potential in the biological control of thrips. Among ladybugs, the most important species in alfalfa and nettle were Propylea quatuordecimpunctata (Linnaeus), Coccinella septempunctata Linnaeus and Hippodamia variegata (Goeze), which consume significant amounts of aphids. The most frequent spider family in alfalfa and nettle was Thomisidae and Philodromidae. The dynamics of their prey composition suggests that these taxa present a significant suppressive force on pests. The predator thrips Aeolothrips intermedius Bagnall that feeds on phytophagous thrips, mites and other soft-bodied arthropods was also significant in the arthropod assemblage of alfalfa. Our three-year investigation showed that the abundance and the species richness of the natural enemies of greenhouse crops are suitably high in both alfalfa and nettle stands. The number of generalist predators, natural enemies of pests, the most versatile tools of pest management reached its peak between mid-May to late June in nettle whereas due to mowing, the highest values for alfalfa were recorded from June to mid-August.
Theridion impressum is one of the dominant foliage dwelling spider species of maize fields in Hungary. Spider webs were collected from Bt and isogenic maize plots in three successive years. Captured insects in the web were identified. The most frequent prey items were aphids, plant hoppers and beetles. Although the number of captured insects in web samples from isogenic maize was slightly higher than those from Bt maize in the case of almost each insect order, except for two samples (Sternorrhyncha, 2001; Neuroptera, 2002), the differences between Bt and isogenic samples were not significant.
Recent years of studies have suggested that the common crab spider (Xysticus kochi) has a great potential against the western flower thrips (Frankliniella occidentalis) . The efficiency of applying a single predator against a pest however, is made uncertain by many different factors. Using a mixture of predators on the other hand, can overcome the difficulties of using a single-species agent, since different predators have different environmental demands and preying habits. Our experiments involved releasing a non-selected assemblage of arthropods, collected by sweep-net in alfalfa and stinging nettle, into greenhouse pepper stands. Interestingly, while there were twice as much thrips in the experimental greenhouses than in the control (mainly conventional) ones, crop yields were similar. The ratio of predators-preys in experimental greenhouses was not different from that in the control greenhouses, too. Probably the release of predators and lack of chemical treatments in experimental stands resulted in a 43% increase in the amount of Orius species. In search of a cost-effective, environment-friendly pest management method, the application of a mass-collected, non-selected assemblages of arthropods has a definite potential. Further investigations are needed to increase the efficiency and to monitor the potential drawbacks of this method.
The characteristics of crystallization, melting and spherulitic growth of a random propylene copolymer (PRC) containing small amount of ethylene were studied in the presence of a selective Β-nucleating agent (calcium pimelate). It was established that the products of isothermal and non-isothermal crystallization are very rich in Β-modification but have mixed polymorphic composition. The formation of α-modification may be attributed to Βα-transition on the surface of growing Β-spherulites resulting in αΒ-twin-spherulites. During melting of PRC of Β-modification, the characteristics observed with Β-nucleated propylene homopolymers, namely, a Βα-recrystallization of recooled samples and separated melting of non-recooled samples (i.e. the melting memory effect), as well as a ΒΒ-recrystallization leading to a perfection of the structure within the Β-modification, are also demonstrated. The disturbance of regularity of the polymer chain highly reduces the tendency to Β-crystallization. In contrast to the observations with propylene homopolymers, the growth rate of α-modification (G α) is higher than that of Β-modification (G β) and no critical crossover temperature can be found (T(Βα)=413 K) below whichG α>G β. The experimental results show that a partial disturbance of chain regularity by incorporation of comonomer units considerably reduces the tendency to Β-crystallization.
A relatively homogeneous group of streptomycete isolates was obtained from netted scab lesions of potato tubers collected from a potato field in Hokkaido, Japan. Based on 55 phenotypic data of 72 Streptomyces strains selected from these isolates together with spectral data on their soluble pigments and with data of a PCR analysis, using species specific primers, these netted scab causing pathogenic organisms were identified as S. acidiscabies. S. acidiscabies had previously been isolated from deep (common) scab lesions in the USA and reported as thaxtomin A producer. In contrast, our S. acidiscabies strains were not able to induce deep scab symptoms on potato minitubers in pot test, did not produce the phytotoxin thaxtomin A and did not contain the pathogenicity related gene, nec-1.
The relationship between virus, host plant and vector species is of primary importance for understanding the development of Tomato Spotted Wilt Virus (TSWV) epidemics. One of the vectors, Thrips tabaci , occurs in Hungarian greenhouses and their surroundings all year round. From June 2005 to May 2007 we conducted studies on weed hosts growing in the vicinity of sweet pepper greenhouses in order to know on which TSWV host weeds the larvae develop in different seasons. Of the 16 TSWV host weeds collected Stellaria media proved to be the most frequent weed species with the greatest abundance and it occurred the whole year round at all five investigated locations. Together with Galinsoga parviflora , which had the highest number of T. tabaci larvae in autumn, S. media is very probably the main source of TSWV for epidemics in greenhouses.
The ovewintering of Frankliniella occidentalis adults was observed in a relativelymild winter in the years of 2006–2007, outdoors in the surroundings of forced beds, under continental climatic conditions, in Hungary.