Addressing the growing need for environmentally friendly fungicides in agriculture, this study explored the potential of biopolymer microparticles loaded with metal ions as a novel approach to combat ...fungal pathogens. Novel alginate microspheres and chitosan/alginate microcapsules loaded with zinc or with zinc and silver ions were prepared and characterized (microparticle size, morphology, topography, encapsulation efficiency, loading capacity, and swelling behavior). Investigation of molecular interactions in microparticles using FTIR-ATR spectroscopy exhibited complex interactions between all constituents. Fitting to the simple Korsmeyer–Peppas empirical model revealed the rate-controlling mechanism of metal ions release from microparticles is Fickian diffusion. Lower values of the release constant k imply a slower release rate of Zn2+ or Ag+ ions from microcapsules compared to that of microspheres. The antimicrobial potential of the new formulations against the fungus Botrytis cinerea was evaluated. When subjected to tests against the fungus, microspheres exhibited superior antifungal activity especially those loaded with both zinc and silver ions, reducing fungal growth up to 98.9% and altering the hyphal structures. Due to the slower release of metal ions, the microcapsule formulations seem suitable for plant protection throughout the growing season. The results showed the potential of these novel microparticles as powerful fungicides in agriculture.
Finding a suitable alternative to the small pool of existing antifungal agents is a vital task in contemporary agriculture. Therefore, intensive research has been conducted globally to uncover ...environmentally friendly and efficient agents that can suppress pathogens resistant to the currently used antimycotics. Here, we tested the activity of boric acid (BA) and its derivative phenylboronic acid (PBA) in controlling the early blight symptoms in tomato plants infected with pathogenic fungus
. By following the appearance and intensity of the lesions on leaves of the tested plants, as well as by measuring four selected physiological factors that reflect plant health, we have shown that both BA and PBA act prophylactically on fungal infection. They did it by reducing the amount and severity of early blight symptoms, as well as by preventing deterioration of the physiological traits, occurring upon fungal inoculation. Phenylboronic acid was more efficient in suppressing the impact of
infection. Therefore, we conclude that BA, and even more so PBA, may be used as agents for controlling early blight on tomato plants, as they are both quite effective and environmentally friendly.
The ascomycete fungus
causes early blight, one of economically the most important tomato diseases. Due to frequent use of fungicides,
has developed resistance with negative economic and environmental ...consequences. Research of new ways to control fungal pathogens has turned its eye to environmentally friendly chemicals with low toxicity such as boronic acids. The aim of our study was therefore to test the antifungal effects of phenylboronic and boric acid
on
.
. We isolated the pathogen from a symptomatic tomato plant and determined the minimum inhibitory concentration of phenylboronic and boric acid on
mycelial growth using the poisoned food technique. The antifungal effect was tested on a wide range of phenylboronic and boric acid concentrations (from 0.04 % to 0.3 %) applied separately to agar with mycelial disc of the pathogen. After five days of incubation, phenylboronic acid at low concentration (0.05 %) completely inhibited mycelial growth. Boric acid, in turn, did not significantly slow down mycelial growth but did reduce sporulation and confirmed its fungistatic effect. Our findings point to the potential use of phenylboronic acid to control phytopathogenic fungi. This is, to our knowledge, the first report on its antifungal effect on an agriculturally important pathogen
. Moreover, since
is also a human pathogen, these results may have clinical ramifications.
In vitro plants that are free of pathogens are crucial for biotechnological breeding methods. The present study investigates the effects of sterilization with sodium hypochlorite (NaClO) and the ...addition of Plant Preservative Mixture (PPMTM) to the growth medium on pathogen elimination, germination, and seedling development of the winter wheat (Triticum aestivum L.) variety Mara. The sterilization treatments differed in the duration of seed sterilization in 4% NaClO and the PPM concentration added to the growth medium. Pathogenic fungi of the genera Aspergillus, Cladosporium, Penicillium, and Bipolaris were completely eliminated when the seeds were sterilized in NaClO and placed on growth media with the addition of PPM. Extending the duration of the sterilization treatment with NaClO to 50 min reduced Fusarium contamination, while the interaction between the 50 min sterilization treatment with NaClO and the addition of PPM to the growth medium reduced Alternaria contamination. Our results suggest that PPM could complement sterilization procedures with NaClO in the introduction of highly infected wheat seeds in vitro. Seed germination was not affected by sterilization with NaClO or by the addition of PPM. However, PPM at a concentration of 4 mL L−1 had a negative effect on seedling development.
Askomicetna gljiva Alternaria alternata uzročnik je koncentrične pjegavosti, jedne od ekonomski najvažnijih bolesti rajčice. Zbog česte primjene fungicida, ta je gljiva razvila otpornost na ...agrokemikalije koje se koriste u njezinu suzbijanju, s negativnim ekonomskim i ekološkim posljedicama. Novi načini suzbijanja gljivičnih patogena uključuju upotrebu ekološki prihvatljivih i manje toksičnih spojeva, među koje potencijalno spadaju boronske kiseline. Pokusom in vitro istražen je antimikotički učinak fenilboronske i borne kiseline na gljivu A. alternata. Nakon izolacije patogena iz rajčice, određena je minimalna inhibitorna koncentracija fenilboronske i borne kiseline za rast micelija primjenom tehnike poisoned food. Antimikotički učinak testiran je na širokom rasponu koncentracija fenilboronske i borne kiseline (od 0,04 % do 0,3 %), pojedinačno umiješanih u hranjivu podlogu na kojima je tijekom petodnevne inkubacije uzgajan micelarni disk kulture patogena. Fenilboronska je kiselina pri niskoj koncentraciji (0,05 %) potpuno inhibirala rast micelija. Primjena borne kiseline u različitom rasponu koncentracija nije značajno umanjila rast micelija, ali je primijećeno smanjenje sporulacije patogena, čime se potvrđuje fungistatski učinak borne kiseline. Prema našoj spoznaji, ovo je prva studija koja opisuje in vitro antimikotički učinak fenilboronske kiseline na patogen koji je važan u poljoprivredi. Štoviše, s obzirom na to da je A. alternata i patogen ljudi, studija ima i potencijalni medicinski značaj.
Negativni ekološki i ekonomski učinci pesticida rastu s njihovom prekomjernom primjenom, što je posljedica pogrešne procjene jačine zaraze biljaka. Pogrešna procjena dovodi do provođenja neadekvatnih ...metoda suzbijanja biljnih patogena i aplikacije prekomjernih doza pesticida u poljoprivrednoj praksi. U svrhu održive zaštite bilja, objektivna i ispravna procjena jačine zaraze biljaka te donošenje odluke o suzbijanju patogena, dugoročno se smatra isplativom metodom. Osim toga, pouzdane procjene jačine zaraze važne su i za predviđanje gubitka prinosa, oplemenjivanje biljaka, praćenje patogena i razvoja otpornosti na pesticide. Suvremene digitalne tehnike preteča su klasičnim tehnikama, kao što su vizualni pregledi koji koriste ljestvice (skale) s određenim numeričkim rasponom. Digitalne tehnike za kvantifikaciju bolesti na biljkama koriste digitalne slike poput fotografija, sken-slika i hiperspektralnih slika, međutim takva procjena ovisi o kvaliteti i karakteristikama slike koja se analizira. Napretkom tehnologije razvijeni su računalni programi (software), a u novije vrijeme i aplikacije za pametne mobitele za brže i preciznije određivanje jačine zaraze biljaka. Aplikacija Leaf Doctor inovativna je poluautomatska tehnika čija primjena reducira vrijeme i napor uložen u procjenu jačine zaraze u terenskim istraživanjima. Ovim preglednim radom predstavit će se poznate karakteristike digitalnih tehnika za procjenu jačine zaraze biljnih bolesti te navesti kriteriji za preciznu kvantifikaciju simptoma na temelju digitalnih slika. Usporedbom računalnog programa (ImageJ) i mobilne aplikacije (Leaf Doctor) s klasičnim pristupom (vizualnim pregledom biljaka), stiče se uvid u mogućnosti bržeg, jednostavnijeg i preciznijeg određivanja stupnja bolesti biljaka, što je važno u fitopatološkim istraživanjima te dugoročno isplativo za biljnu proizvodnju.
Biljna proizvodnja suočava se s velikim troškovima pronalaska, razvoja i komercijalizacije novih proizvoda za zaštitu bilja jer biljni patogeni sve brže razvijaju otpornost na sredstva namijenjena ...njihovu suzbijanju. Zbog toga postoji velika potreba za razvojem alternative koja može ponuditi ekološki i ekonomski prihvatljivu zaštitu bilja. Mikroorganizmi koji žive unutar biljaka sve više postaju predmetom istraživanja. Riječ je o endofitima čija bi primjena, kao sredstava za biološko suzbijanje, potencijalno dovela do smanjenja uporabe kemijskih sredstava za zaštitu bilja. Poznato je da endofitni mikroorganizmi promoviraju rast biljnog domaćina i induciraju otpornost biljke koju koloniziraju. Također, zbog svojih jedinstvenih simbiotskih interakcija unutar biljnih domaćina, antagonistički djeluju na biljne patogene. Zanimljivo je da jedan endofitni mikrooganizam može djelovati na patogena kombinirajući više antagonističkih mehanizama borbe, ali isto tako može imati dvojnu biološku aktivnost kada se govori o učinku na ciljanog patogena ili štetnika. Ovaj rad približava razumijevanje trostruke interakcije (endofit-biljka domaćin-patogen) te stavlja naglasak na potrebu uključivanja endofita u probir zbog pronalaska novih spojeva u svrhu biološkog suzbijanja.
Current serology tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies mainly take the form of enzyme-linked immunosorbent assays, chemiluminescent microparticle ...immunoassays or lateral flow assays, which are either laborious, expensive or lacking sufficient sensitivity and scalability. Here we present the development and validation of a rapid, low-cost, solution-based assay to detect antibodies in serum, plasma, whole blood and to a lesser extent saliva, using rationally designed split luciferase antibody biosensors. This new assay, which generates quantitative results in 30 min, substantially reduces the complexity and improves the scalability of coronavirus disease 2019 (COVID-19) antibody tests. This assay is well-suited for point-of-care, broad population testing, and applications in low-resource settings, for monitoring host humoral responses to vaccination or viral infection.
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