Cilj istraživanja bio je primjenom digitalnog mikroskopa utvrditi utjecaj i dinamiku učinka različitih koncentracija herbicida pendimetalina na rast bakterije Bradyrhizobium japonicum. Istraživane ...koncentracije pendimetalina iznosile su 0,00; 0,165; 0,33; 0,66; 1,32 i 2,64%. Koncentracija 0,66% odgovara količini pendimetalina koja se uobičajeno primjenjuje u praksi (registrirana dozacija). Utjecaj pendimetalina na rast bakterija utvrđivan je mjerenjem širine zone inhibicije oko filter-diskova tretiranih istraživanim koncentracijama pendimetalina 5, 7, 10 i 12 dana nakon nacjepljivanja (DNN) bakterija na hranjivu podlogu. Najmanji inhibitorni učinak utvrđen je kod prvog mjerenja (5 DNN), kad se prosječna širina zone inhibicije kretala od 0,18 mm kod najniže (0,165%) do 0,97 mm kod najviše (2,64%) istraživane koncentracije. Pri svakom sljedećem mjerenju utvrđena je progresija inhibitornog učinka pendimetalina na rast bakterija. Najveći inhibitorni učinak utvrđen je kod posljednjeg mjerenja (12 DNN) kad je širina zone inhibicije kod koncentracije pendimetalina od 0,165% iznosila 0,61 mm. Povećanjem koncentracije znatno se povećavala, te je kod koncentracije od 2,64% iznosila 2,46 mm. Rezultati istraživanja ukazuju na negativan učinak herbicida pendimetalina na rast bakterija B. japonicum čak i kod koncentracija manjih od preporučene koja se primjenjuje u praksi.
The objective of this study was to determine the effect of different concentrations of herbicide pendimethalin on the growth of nitrogen-fixing bacteria Bradyrhizobium japonicum using a digital microscope. Pendimethalin was applied at concentrations of 0.00; 0.165; 0.33; 0.66; 1.32 and 2.64%, where the concentration of 0.66% presents the amount of herbicide which is usually applied in the field (recommended dose). The influence of pendimethalin on the growth of B. japonicum was determined by measuring the width of the inhibition zone around the discs 5, 7, 10 and 12 days after inoculation (DAI) of bacteria on a nutrient medium. The lowest inhibitory effect of pendimethalin for all concentrations determined was 5 DAI, when the average width of inhibition zone was between 0.18 mm for the lowest (0.165%) to 0.97 mm for the highest (2.64%) concentration. The progression of the inhibitory effect of pendimethalin occurred with every following assessment. The highest inhibitory effect determined was 12 DAI, when the width of the inhibiton zone at a concentration of 0.165% was 0.61 mm. The width of the inhibition zone significantly increased with increasing the pendimethalin concentrations and at a concentration of 2.64% it was 2.46 mm. The results of this study indicate the negative effect of herbicide pendimethalin on bacteria B. japonicum, even at concentrations lower than recommended concentrations that are applied in the field.
U posljednjih se desetak godina postavljanje granica u odgoju djece kao temeljnog pedagoškog procesa socijalizacije u obitelji sve manje istražuje. Posebno je to vidljivo u istraživanjima koja se ...bave djecom s teškoćama rane i predškolske dobi gdje se naglasak stavlja na potvrđivanje učinaka pojedinih programa i njihove znanstvene utemeljenosti, dok se primarna funkcija interpersonalnih relacija na razini djetetovog proksimalnog okruženja rijetko adresira. Drugim riječima, postoji svojevrsni znanstveni bias prema pedagoškim postupcima u obitelji, tj. odgojnim strategijama iako temeljne spoznaje s područja pedagogije i psihologije govore o tvorbenim učincima roditeljskih obrazaca izvanjske regulacije dječjeg ponašanja u smjeru autonomije ili heteronomije u odrasloj dobi. Stoga je u veljači i ožujku 2020. godine provedeno intervjuiranje roditelja djece s teškoćama u razvoju (N=100) o odgojnim strategijama koje prakticiraju. Utvrđeno je postojanje dviju temeljenih kategorija odgojnih strategija roditelja: strategije aktivacije, tj. nagrađivanja djece i strategije inhibicije, tj. kažnjavanja. Kao nagradama roditelji se koriste hranom, tabletom/mobitelom i omiljenom aktivnosti, dok kao kazne primjenjuju tzv. time-out, uskraćivanje omiljenog predmeta (tableta/mobitela) i aktivnosti te fizičko kažnjavanje. Postojeće stanje pokazuje kako roditelji djece s teškoćama u razvoju nemaju dostatnu društvenu podršku u iznošenju svojih roditeljskih uloga, što je u budućnosti potrebno adresirati znanstveno utemeljenim programima podrške roditeljima.
In the last ten
years, establishing and maintaining boundaries in raising children, as a basic
pedagogical process of socialisation, has become less researched. This issue is
even less explored with young children with disabilities; the emphasis is on
the developmental outcomes of the particular programme and its scientific
foundation. In contrast, the fundamental function of interpersonal
relationships in a child’s proximal environment is not interesting for
scholars. In other words, there is a scientific bias towards pedagogical
strategies within families, i.e. raising strategies. However, basic knowledge
from the field of pedagogy and psychology speaks in favour of its long term outcomes
for one’s autonomy or heteronomy in adulthood. Therefore, regarding their
parenting strategies, an interview with parents of children with disabilities
(N=100) was conducted during February and March 2020. The existence of two
significant categories of parenting strategies was established: activation
strategies, i.e., rewards, and inhibition strategies, i.e., punishments.
Parents use food, tablets/mobile phones and preferred activities as rewards
while using time-out, withdrawal of the preferred object and physical
punishment as punishments. Obtained results indicate that parents of children
with developmental disabilities don't have adequate social support for their
parental roles, which should be addressed in the future through scientifically
based programmes for parents.
Glyphosate has remained the leading herbicide on the global market to date, despite the continuous debate between consumers, scientific community, and regulatory agencies over its carcinogenicity, ...genotoxicity, environmental persistence, and the role in the development of neurodegenerative disorders. Chemically, glyphosate belongs to a large family of organophosphorus pesticides, which exert a neurotoxic effect by inhibiting acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), enzymes of the cholinergic system essential for maintaining neurotransmission. Although research shows that glyphosate is a weak cholinesterase inhibitor in fish and mammals compared to other OP compounds, no conclusive data exist concerning the inhibition of human AChE and BChE. In our study we analysed its inhibitory potency on human AChE and BChE, by establishing its IC
and reversible inhibition in terms of dissociation inhibition constants. Glyphosate concentration of 40 mmol/L caused near total inhibition of enzyme activity (approx. 10 % activity remaining). Inhibition dissociation constants (
) of glyphosate-AChE and -BChE complexes were 28.4±2.7 mmol/L and 19.3±1.8 mmol/L, respectively. In conclusion, glyphosate shows a slight binding preference for BChE but exhibits inhibition only in a high concentration range. Our results are in line with studies reporting that its neurotoxic effect is not primarily linked to the cholinergic system.
The generally accepted concept of the necessity of producing safe foods has indirectly influenced the decision to replace chemical preservatives
with natural ones. Bacteriocins, and in particular ...those synthesized by
lactic acid bacteria (LAB) in the food industry, are considered to be their effective replacement. In controlling the growth of microbial pathogens and/or the occurrence of pathogenic bacteria in food, with the
permitted nisin and pediocin, a significant antibacterial effect has been shown for most LAB bacteriocins. However, the use of purified bacteriocins as bio preservatives in cheese production is limited. To inhibit the growth of bacteria L. monocytogenes, S. aureus and C. tyrobutyricum in cheese, bacteriocinogenic LAB strains contained in primary, adjunct or protective culture are much more acceptable in cheese production.
Opće prihvaćen koncept o nužnosti proizvodnje zdrave i sigurne hrane neizravno je utjecao na odluku da se i kemijski konzervansi zamijene prirodnim. Bakteriocini, a osobito oni koje sintetiziraju bakterije mliječne kiseline (BMK) u prehrambenoj se industriji smatraju njihovom učinkovitim zamjenom. U kontroli rasta mikrobnih uzročnika kvarenja i/ili pojavnosti patogenih bakterija u hrani, uz dopušteni nizin i pediocin i za većinu je do sada opisanih i pročišćenih bakteriocina BMK utvrđen značajan antibakterijski učinak. Međutim, primjena pročišćenih bakteriocina kao biokonzervansa u proizvodnji sira je limitirana. Za inhibiciju rasta bakterija L. monocytogenes, S. aureus i C. tyrobutyricum u siru, znatno su prihvatljiviji bakteriocinogeni sojevi BMK sadržani u primarnoj, dopunskoj ili protektivnoj kulturi od pročišćenih bakteriocina.
Poljski jasen (Fraxinus angustifolia), važna pionirska vrsta drveća u poplavnim šumama u Hrvatskoj, posljednjih godina pokazuje sve izraženije simptome odumiranja, za koje je jedan od odgovornih ...čimbenika patogena gljiva Hymenoscyphus fraxineus. Istraživanja pokazuju da postoji mogućnost biološke kontrole patogena uporabom endofita, gljiva koje se prirodno nalaze u zdravom biljnom tkivu i koje ne uzrokuju vidljive simptome bolesti, a čiji je velik broj potvrđen i u poljskom i običnom jasenu (F. excelsior). U ovom je istraživanju ispitan antagonistički učinak triju vrsta: Trichoderma capillare, T. harzianum i T. tomentosum, jer su prijašnja istraživanja pokazala kako su pripadnici ovoga roda najučestaliji endofiti poljskoga jasena u Hrvatskoj. U tu su svrhu postavljene dvojne kulture dvaju izolata gljive H. fraxineus s po jednim izolatom svake vrste roda Trichoderma, u kojima je mjeren rast patogena te bilježen tip međusobne interakcije. Također su uspostavljene i kontrolne kulture te kulture za praćenje samoinhibicije patogena. Rezultati su pokazali kako tri korištene vrste roda Trichoderma mogu inhibirati rast patogena in vitro, pri čemu su T. harzianum i T. tomentosum pokazale veći antagonizam s obzirom na tip ostvarene interakcije. Unatoč pozitivnim rezultatima potrebna su daljnja istraživanja, u prvom redu in planta, za potvrdu učinkovitosti vrsta roda Trichoderma u inhibiciji gljive H. fraxineus izvan laboratorijskih uvjeta.
Narrow-leaved ash, an important pioneer tree species in Croatian floodplain forests, is suffering severe dieback in the last years, mostly due to the pathogenic fungus Hymenoscyphus fraxineus. Multiple studies have shown that there is a possibility to control the pathogen with the use of endophytes, fungi that naturally occur in healthy plant tissue without causing any visible disease symptoms. As species of genus
Trichoderma were found to be the most common endophytes of narrow-leaved ash root and stem in Croatia, in this research we tested the antagonistic activity of Trichoderma capillare, T. harzianum and T. tomentosum (each represented with one isolate) against H. fraxineus (represented with isolates HF16 and HF 120) in dual cultures. Control cultures with sterile agar plugs and self-inhibition cultures with two plugs of H. fraxineus mycelium were also established. All cultures were prepared in five repetitions, resulting in a total of 50 combinations. Total growth, i.e. the colony radius of H. fraxineus was measured in three directions at four time points, first after 10 days of its independent growth, and then weekly after placing the challenge isolates
in cultures. Both H. fraxineus isolates stopped growing in dual cultures with all three Trichoderma species in the period between the second and third measurement, i.e. 7-14 days after confrontation, while the ones in control and self-inhibition cultures continued growing. Fisher LSD test revealed that there was a significant impact of T. harzianum and T. tomentosum on growth reduction of both H. fraxineus isolates compared to pathogen’s growth in control cultures, while T. capillare significantly inhibited the growth of one isolate only (HF16).
The same test showed that there was no significant difference in inhibition among used Trichoderma species, however, T. harzianum and T. tomentosum overgrew H. fraxineus completely (complete replacement) in the first 7 days of confrontation in all dual cultures, while T. capillare accomplished only partial replacement of the pathogen in 14 or
21 days of confrontation, depending on the culture. Also, the latter was the only species in this research inhibited reciprocally by the pathogen, i.e. there was a formation of the sterile zone without Trichoderma capillare growth (initial deadlock) visible in all dual cultures. Although our results support the possibility of using Trichoderma species in biological suppression of H. fraxineus, further extensive research is needed, with more frequent measurements encompassing more isolates of both the pathogen and these endophytes, and focusing on investigating exact mechanisms of inhibition and testing
the efficiency in planta.
Na važnosti propolisa u ekološkoj poljoprivredi zbog njegovog antifungalnog djelovanja ukazuju brojna istraživanja. U provedenom istraživanju utvrđen je utjecaj alkoholnog propolisa na rast 4 ...fitopatogene gljive: Alternaria brassicae, Botrytis cinerea, Fusarium oxysporum i Sclerotinia sclerotiorum. Korištene su 3 koncentracije otopine propolisa (0,5 %, 1 % i 2,5 %). Svaka od navedenih koncentracija imala je manji ili veći inhibitorni učinak na porast micelija fitopatogenih gljiva. Potpuno inhibitorno djelovanje na porast B. cinerea, A. brassicae i F. oxysporum imala je koncentracija 2,5 %, dok je porast zabilježen na koncentraciji od 0,5 %. Pri koncentraciji 1% propolisa utvrđene su statistički visoko značajne razlike između porasta micelija kod navedenih gljiva. S. sclerotiorum nije se razvila niti na jednoj koncentraciji te je propolis pokazao potpuno inhibitorno djelovanje na porast ove gljive.
Cilj istraživanja bio je utvrditi utjecaj 22 eterična ulja (anis, timijan, kim, paprena metvica, lavanda, kadulja, matičnjak, ružmarin, mirta, cimet list, bosiljak, bijeli bor, eukaliptus, cedar, ...bergamot, mandarina, čempres, pačuli, đumbir, gorka naranča, sandal, kamfor) na porast micelia Botrytis cinerea, uzročnika sive plijesni. Pokus je proveden u uvjetima in vitro na PDA podlozi u 2 ponavljanja. Ulja su primijenjena u tri količine (3, 5 i 7 μl), porast micelija mjeren je nakon 3 i 9 dana. Sva ulja, izuzev ulja gorke naranče, sandala i kamfora, pokazala su određeno antifungalno djelovanje. U odnosu na Kontrolu, najbolji učinak imala su ulja timijana i anisa, dok je za ulja gorke naranče, sandala i kamfora utvrđen stimulativni učinak na rast gljive B.cinerea.
Derivati izoindolina pokazuju vrlo različita biološka djelovanja in vitro, a neki djeluju i u uvjetima in vivo. Stoga se može očekivati da će istraživanja u budućnosti dovesti i do učinkovitih ...lijekova za različite vrste bolesti. Pokazuju nesteroidnu protuupalnu aktivnost, antihipertenzivno djelovanje, anksiolitičko, antipsihotičko i antikonvulzivno djelovanje. Djeluju kao lokalni anestetici, vazodilatatori te se vežu na dopaminske i serotononske receptore. Ubrajaju se također u skupinu antidijabetika inhibirajući dipeptidil-peptidaze. Metalni kompleksi izoindolina i njegovih derivata djeluju poput enzima katalaze koji štiti stanice od štetnog djelovanja vodikova peroksida te djeluju i kao inhibitori protein-kinaza. Osim ostalih značajno je njihovo antitumorsko djelovanje na stanice leukemije, karcinoma debelog crijeva, epidermalnog karcinoma te karcinoma jajnika. Oni također inhibiraju enzime koji potiču rast tumorskih stanica kao što su histon deacetilaza te receptori tirozin-kinaze i krvožilnog endotelnog čimbenika rasta (VEGF-R2).
The in vitro effect of five commonly used herbicides viz., pyridate, fluazifop-P-butyl, foramsulfuron, tembotrione and S-metolachlor on mycelial growth of entomopathogenic fungus Beauveria bassiana ...(ATCC 74040) was evaluated each at different concentrations: 100, 75, 50, 25, 12.5, 6.25 and 0% of recommended field application rate on PDA agar plates at 15 and 25°C. The herbicides tested were classified in 1-4 scoring categories based on reduction in mycelial growth: 1 = harmless (<25% reduction), 2 = slightly harmful (25-50%), 3 = moderately harmful (51-75%), harmful (>75%) in toxicity tests. All the five herbicides had fungistatic effect to B. bassiana at varying intensities depending on their concentrations in medium. The present study showed that B. bassiana is very sensitive to the herbicides tested, particularly at recommended as well as lower field dosage. The selected herbicides foramsulfuron, tembotrione and S-metolachlor have strong fungistatic effect on mycelial growth (> 75% inhibition) at 15 °C and concentrations from 50 to 100%. Foramsulfuron has fungicidal effect at 100 % concentration. Foramsulfuron, tembotrione and S-metolachlor were less inhibitory at 25 than at 15 °C, but the temperature had no influence on reduction of mycelial growth at pyridate and fluazifop-P-butyl. Of the herbicides tested, pyridate and fluazifop-P-butyl showed less adverse effects and are probably compatible with B. bassiana in the field. However, extensive field studies complemented by parallel laboratory experiments should consider assessing the interaction between selected herbicides and B. bassiana isolates to evaluate their ecological impact in cropped environments.
V in vitro poskusih smo na PDA agarnih ploščah in temperaturah 15 ter 25 °C preučevali učinek petih pogosto uporabljanih herbicidov, in sicer piridata, fluazifop-P-butila, foramsulfurona, tembotriona in S-metolaklora na rast micelija entomopatogene glive B. bassiana (ATCC 74040) pri različnih koncentracijah: 100, 75, 50, 25, 12,5, 6,25 in 0 % priporočenega poljskega odmerka. Glede na inhibicijo rasti micelija smo po toksikoloških testih preučevane herbicide razvrstili v štiri razrede: 1 = neškodljiv (<25 % inhibicija), 2 = malo škodljiv (25 - 50 %), 3 = zmerno škodljiv (51 - 75 %), 4 = škodljiv (> 75 %). Vseh pet herbicidov ima fungistatičen učinek na glivo B. bassiana, na obseg pa vpliva njihova koncentracija v gojišču. Raziskava je pokazala, da je gliva B. bassiana zelo občutljiva na preizkušane herbicide, posebej pri priporočenih poljskih koncentracijah, pa tudi pri manjših odmerkih. Pri temperaturi 15 °C in koncentracijah od 50 do 100 % imajo herbicidi na podlagi foramsulfurona, tembotriona in S-metolaklora izrazit fungistatičen učinek (> 75% inhibicija), pri 100 % odmerku pa ima foramsulfuron celo fungicidni učinek. Foramsulfuron, tembotrion in S-metolaklor so bili manj inhibitorni pri 25 kot 15 °C. Temperatura ni vplivala na inhibicijo rasti micelija pri piridatu in fluazifop-P-butilu. Od vseh preizkušanih herbicidov sta imela piridat in fluazifop-P-butil najmanj zaviralnih učinkov in bi jih lahko uporabljali na pridelovalnih površinah skupaj z glivo B. bassiana. Poleg laboratorijskih testov s herbicidi bi morali izvajati vzporedne poskuse na pridelovalnih površinah, da bi dejansko izvrednotili njihov ekološki vpliv na glivo B. bassiana
Successful total RNA (totRNA) extraction is a prerequisite for a successful real-time PCR. In the present work we compared one manual and one automated totRNA extraction method for detection of Plum ...pox potyvirus (PPV) in leaves of different Prunus sp. using developed real-time RT-PCR assay. Advantages and disadvantages of compared methods are described in the view of sensitivity, reproducibility and in terms of laboratory use. The results suggest that the column based totRNA extraction method is more effective for apricot, plum and peach. In the case of damson the differences in real-time PCR results between both extraction methods were negligible. In case of negative results obtained with automated method, manual column based extraction method should be used additionally.
Uspešnost izolacije RNA je osnova za uspešno izvedbo reakcije PCR v realnem času (qPCR). V svojem delu smo primerjali ročno in avtomatsko metodo izolacije celokupne RNA (totRNA) iz listov različnih rastlinskih vrst iz rodu Prunus. Uspešnost izolacije totRNA smo preverjali z uvedeno metodo qPCR za detekcijo virusa šarke (Plum pox potyvirus - PPV). Prednosti in slabosti uporabljenih metod smo ugotavljali s primerjavo občutljivosti detekcije, ponovljivosti in intenzivnosti laboratorijskega dela. Rezultati raziskave so pokazali, da je ročna metoda izolacije totRNA učinkovitejša pri marelicah, breskvah in slivah, medtem ko so bile razlike med obema metodama pri ciborah zanemarljive. Pri uporabi preizkušene avtomatske metode izolacije totRNA je priporočljivo, da v primeru negativnih rezultatov le-te še dodatno preverimo z uporabo ročne metode izolacije.
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