Vilina kosica - životni ciklus i interakcija sa domaćinom

Field dodder is a parasitic plant that attaches to stems and leaves of broadleaf plants, including weeds, field crops, vegetables and ornamentals, across most agricultural regions of the world. Effective field dodder control is extremely difficult to achieve due to the nature of attachment and close association between the host and the parasite, which require a highly effective and selective herbicide to destroy the parasite without damaging its host. To establish a strategy for controlling parasite growth and restricting the spread of field dodder in crop fields, it is important to learn more about this weed, its life cycle and development.Vilina kosica je parazitska cvetnica koja se vezuje za stablo i lišće biljaka domaćina i parazitira značajan broj ekonomski značajnih vrsta, korove i ukrasno bilje. Postoje različite mere koje se mogu preduzeti za suzbijanje viline kosice, počev od preventivnih (čist semenski materijal, otporne sorte), preko mehaničkog uklanjanja (košenje, ručno uklanjanje) do korišćenja herbicida, ali je veoma teško postići efektivnu kontrolu ove parazitne cvetnice, zbog prirode vezivanja sa biljkom domaćinom. Za pravljenje dobre strategije u suzbijanju viline kosice pored integrisanja gore pomenutih mera, neophodno je i poznavanje njenog razvoja i životnog ciklusa

Biology of field dodder (Cuscuta campestris Yunk.) and options for its control

Radi sagledavanja kompletne biologije, ekologije i mogućnosti suzbijanja Cuscuta campestris Yunk. urađena je determinacija 23 populacije vilinih kosica primenom svetlosne i skening elektronske mikroskopije, a potom i molekularnim metodama (PCR). Takođe, ispitivan je uticaj različitih temperaturnih režima i rizobakterija (PGPR) na klijanje semena C. campestris, kao i uticaj različitih svetlosnih tretmana (crvene, daleko crvene i plave svetlosti) na klijanje, rast i visinu vezivanja klijanaca viline kosice za stablo lucerke. Proučavan je uticaj C. campestris na morfološke (vizuelna ocena i sveža masa), anatomske (anatomska građa lista i stabla lucerke; lista i lisne drške šećerne repe) i fiziološke parametre (relativni sadržaj hlorofila, ukupni karotenoidi, azot, fosfor, kalijum, organska i mineralna materija i fluorescencija hlorofila) kod biljaka lucerke i šećerne repe u uslovima sa i bez primene herbicida (imazetapira, glifosata, propizamida). Efikasnost imazetapira, glifosata, propizamida i dikvata za suzbijanje viline kosice u lucerištu je ispitivana u poljskim uslovima. Determinacijom 23 populacije vilinih kosica ustanovljene su dve vrste roda Cuscuta i to: Cuscuta campestris Yunk. i Cuscuta epithymum (L.) Nath.. Ustanovljeno je da je optimalna temperatura za klijanje semena C. campestris 30˚C, dok je pri tretmanu sa crvenom svetlošću (1h u toku dana) procenat klijanja semena bio najveći, a u tretmanu sa daleko crvenom svetlošću (45 min u toku dana) je zabeležen najveći procenat vezanih klijanaca za stablo lucerke na visini od 4,65 cm. Takođe, najveći procenat klijanja viline kosice je zabeležen pri tretemanu sa rizobakterijom Azotobacter chroococcum izolovanom iz rizosfere pšenice. Na osnovu analize dobijenih rezultata utvrđeno je da su za većinu merenih parametara (vizuelna ocena i sveža masa; relativni sadržaj hlorofila i ukupnih karotenoida, efektivni prinos i intezitet fluorescencije, varijabilna fluorescencija, odnos varijabilne i maksimalne fluorescencije; debljina epidermisa stabla, debljina primarne kore, debljina centralnog cilindra i prečnik stabla lucerke; debljina epidermisa lica i naličja lista, debljina palisadnog i sunđerastog tkiva, debljina mezofila lista lucerke i šećerne repe; prečnik traheja, hidraulična provodljivost lisne drške, površina ksilema, prečnik ćelija floema i površina floema lisne drške šećerne repe) najveće vrednosti bile kod nezaraženih biljaka lucerke i šećerne repe, zatim kod zaraženih a tretiranih herbicidima i najmanje kod zaraženih sa C. campestris a ne tretiranih biljaka. C. campestris je uticala na smanjenje gotovo svih merenih parametara anatomske građe stabla, listova i lisne drške biljaka domaćina, što nije bio slučaj kod pojedinih fizioloških parametara...Determination of 23 populations of field dodder was conducted using light and scanning electron microscopy and subsequent molecular (PCR) methods in order to fully examine the biology and ecology of Cuscuta campestris and options for its control. The effects of different temperatures and rhizobacteria (PGPR) on germination of C. campestris seeds, as well as effects of different light treatments (red, far-red and blue light) on germination, growth, and height of attachment points of field dodder shoots on alfalfa stems were also investigated. We examined the effects of C. campestris on morphological (visualisation and fresh weight), anatomical (anatomy of leaf and stem of alfalfa; leaf and petiole of sugar beet) and physiological parameters (relative chlorophyll content, total carotenoids, nitrogen, phosphorus, potassium, organic and mineral matter and chlorophyll fluorescence) in alfalfa and sugar beet plants exposed and unexposed to herbicides (imazethapyr, glyphosate, propyzamide). The efficacy of imazethapyr, glyphosate, propyzamide and diquat in controlling field dodder in alfalfa crop was examined in field trials. After examining 23 populations of field dodder, two species of the genus Cuscuta were identified: Cuscuta campestris Yunk. and Cuscuta epithymum (L.) Nath. An optimal temperature for germination of C. campestris seeds was found to be 30˚C and treatment with red light (for 1h at daytime) produced the highest percentage of germinated seeds, while the highest percentage of seedlings attached to alfalfa stems at 4.65 cm height was found after treatment with far-red light (for 45 min at daytime). Also, the highest percentage of germinated field dodder seeds was recorded after treatment with the rhizobacterium Azotobacter chroococcum isolated from wheat rhizosphere. An analysis of our data showed that the highest values of most parameters (visualization and fresh weight; relative content of chlorophyll and total carotenoids, effective yield and intensity of fluorescence, variable fluorescence, variable/maximal fluorescence ratio; thickness of stem epidermis, thickness of cortex, thickness of central cylinder and stem diameter of alfalfa; thickness of upper and lower leaf epidermis, thickness of palisade and spongy mesophylls, thickness of mesophyll in alfalfa and sugar beet leaves; diameter of tracheids, petiole hydraulic conductance, xylem area, diameter of phloem cells and petiole phloem area of sugar beet) were found in non-infested alfalfa and sugar beet plants, then in infested plants treated with herbicides, and the lowest in plants infested by C. campestris but untreated with herbicides. C. campestris was found to affect and reduce nearly all parameters of stem, leaf and petiole anatomy of the host plants, in contrast to some physiological parameters..

Uticaj nikosulfurona na biološku produkciju hibridne forme korovskog suncokreta (Helianthus annuus)

Field experiments were conducted to quantify the effects of nicosulfuron on biological production of weedy sunflower (Helianthus annuus). Plants of this weed species were sown in plots sized 5x4.2 m with inter-row spacing of 24 cm, and 70 cm distance between rows. Plants with two pairs of developed leaves were treated with nicosulfuron using the next rates: 0, 10, 20, 40, 60 and 80 g a.i. ha-1. Vegetative parameters (plant height, fresh weight and leaf area) were recorded five times during vegetation, including the first measurement just before herbicide application and four measurements at intervals of about two weeks. Head and seed production (number of heads per plant, head weight, head diameter, weight of seeds per head, weight of seeds per plant, number of seeds per plant) were determined after seed maturity. The application of nicosulfuron caused growth reduction of weedy sunflower in comparison with the control. All application rates of this herbicide reduced vegetative (height, fresh weight, leaf area) and some generative (number of heads per plant, weight of seeds per plant, number of seeds per plant) parameters, which decreased with increasing rates of nicosulfuron. Effects on the remaining generative test parameters (head weight, head diameter, weight of seeds per head) were not analogous to the effects on other parameters.Efekat nikosulfurona na biološku produkciju hibridne forme korovskog suncokreta (Helianthus annuus) ispitivan je u poljskim ogledima. Biljke ove korovske vrste su posejane na parcelicama veličine 5x4,2 m, sa rastojanjem biljaka u redu od 24 cm i razmakom između redova od 70 cm. Biljke u fazi dva para razvijenih listova su tretirane nikosulfuronom, koji je primenjen u sledećim količinama: 0, 10, 20, 40, 60 i 80 g a.s. ha-1. Vegetativni parametri (visina biljaka, sveža masa i površina listova) su mereni pet puta tokom vegetacije, što uključuje prvo merenje neposredno pre primene herbicida i četiri merenja u intervalima od oko dve nedelje. Produkcija glavica i semena (broj glavica po biljci, masa glavice, prečnik glavice, masa semena po glavici, masa semena po biljci, broj semena po biljci) je određena nakon sazrevanja semena. Primena nikosulfurona je prouzrokovala redukciju rasta hibridne forme korovskog suncokreta u poređenju sa kontrolom. Sve količine ovog herbicida su redukovale vegetativne (visina biljaka, sveža masa i površina listova) i neke generativne (broj glavica po biljci, masa semena po biljci, broj semena po biljci) parametre, koji su se smanjivali sa povećanjem količine nikosulfurona. Efekat na ostale generativne parametre (masa glavice, prečnik glavice, masa semena po glavici) nije bio uporediv sa efektom na ostale parametre

Chemical composition and in vitro herbicidal activity of five essential oils on Johnson grass (Sorghum halepense [L.] Pers.)

The evaluation of the inhibition effect achieved by essential oils of dill (Anethum graveolens L.), oregano (Origanum vulgare L.), juniper (Juniperus communis L.), sage (Salvia officinalis L.) and winter savory (Satureja montana L.) on seed germination and shoot growth of Johnson grass (Sorghum halepense L.) was tested in laboratory. The chemical composition of essential oils was analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The major constituents were carvon (40.5%) and limonene (32.2%) for A. graveolens essential oil, carvacrol (73.7%) for O. vulgare essential oil, α-pinene (43.5%) for J. communis essential oil, b-thujone (32.7%) and camphor (17.2%) for S. officinalis essential oil, thymol (44.6%) and p-cimene (13.4%) for S. montana essential oil. The in vitro study on herbicidal activity was carried out on seed germination and shoots length of S. halepense; A. graveolens, O. vulgare, S. montana essential oils significantly inhibited the germination and shoot length and their herbicidal activity could be attributed mainly to their high content of carvone, carvacrol and thymol. A. graveolens, O. vulgare and S. montana essential oils reduced seed germination by 61.5%, 52.7% and 47.3%, respectively, while J. communis and S. officinalis essential oils stimulated germination (7.7% and 2.2%, respectively). The shoot growth reduction for almost all essential oils, except J. communis essential oil, was more than 30%. The solution of A. graveolens, O. vulgare and S. montana essential oils exhibited more powerful bio-herbicidal effect compared to J. communis and S. officinalis essential oils on the germination and shoot growth of S. halepense.

Phytochemical, Free Radical Scavenging and Antifungal Profile of Cuscuta campestris Yunck. Seeds

This work was conceptualized with the goal to investigate the phytochemical, free radical scavenging and antifungal profile of Cuscuta campestrisYunck. seeds. Total phenolics, amino acid and carbohydrate contents were evaluated in ethanolic, acetone and chloroform extract. Effective antioxidant activity was evaluated throughout seven antioxidant methods. The antifungal activity was assessed against eight fungal strains and Candida albicans. The results showed total phenol, flavonoid, flavonols and phenolic acids contents in amount of 1.51-6.35mg GAE/mL, 78-425g RU/mL, 1.04-2.98mg QU/g and 12.01-30.58g CAE/mL, respectively. The total amino acids and carbohydrates content ranged from 8.29 to 185.45g Gly/mL and from 0.05 to 0.12g Glu/mL. The ethanolic extract showed the best antioxidant activity in phosphomolybdenum, DPPH free radical scavenging, ferric reducing power and lipid peroxidation assays. The best activity in ferrous ion chelating and H2O2 assays had the acetone extract, whereas the best hydroxyl radical scavenging activity was observed with the chloroform extract. The ethanolic extract at a concentration of 6mg/mL proved to be the most effective antimycotic, since it inhibited the growth of all tested fungi except Penicillium verrucosum. The obtained results indicate that C.campestris seeds could be attributed to a potential source of natural antioxidants in food and pharmaceutical products.This is the peer-reviewed version of the article: Jakovljević, V. D.; Vrvić, M. M.; Vrbničanin, S.; Sarić-Krsmanović, M. Phytochemical, Free Radical Scavenging and Antifungal Profile of Cuscuta Campestris Yunck. Seeds. Chemistry & Biodiversity 2018, 15 (8). [https://doi.org/10.1002/cbdv.201800174]

Uticaj temperature na klijanje semena Cuscuta campestris Yunk.

Studies of biological characteristics of seeds and conditions for their germination have a major importance for planning and executing rational measures of weed control. The aim of this study was to investigate the effect of different temperatures on germination of C. campestris seeds. Three treatments (T1- storage at room temperature; T2 - exposure to 4°C for 30 days; T3 - scarification by concentrated sulphuric acid) differing in manipulation with seeds before germination were tested at different temperatures (5°C, 10°C, 15°C, 20°C, 25°C, 30°C, 35°C, 40°C, 45°C). Germinated seeds were counted daily for ten days and the length of seedlings was measured on the last day. The results showed that differences in germination of C. campestris seeds were very prominent between temperatures, as well as between treatments T1, T2 and T3. Seeds failed to germinate at 5°C and 45°C in all treatments (T1, T2, T3). Germination ranged from 6.25 at 10°C to 96.88%, the highest percentage, achieved at 30°C.Izučavanje bioloških karakteristika semena i uslova u kojima klijaju ima veliki značaj za planiranje i realizaciju racionalnih mera za kontrolu korova. Cilj ovog istraživanja je bio da se ispita efekat različitih temperatura na klijanje semena C. campestris. U ogled su bila uključena tri tretmana (T1 - semena čuvana u laboratorijskim uslovima na temperaturi 22- 25°C, T2 - semena koja su prethodno 30 dana izlagana niskoj temperaturi (4°C), T3 - semena koja su skarifikovana koncentrovanom sumpornom kiselinom), pri čemu su svi tretmani ispitivani na sledećim temperaturama: 5°C, 10°C, 15°C, 20°C, 25°C, 30°C, 35°C, 40°C, 45°C. Svakodnevno, u periodu od deset dana, rađeno je prebrojavanje proklijalih semena, a poslednjeg dana su izmerene i dužine klijanaca. Dobijeni rezultati ukazuju da postoje značajne razlike u klijanju semena u odnosu na ispitivane temperature i tretmane. Semena nisu klijala na temperaturama od 5°C i 45°C ni u jednom od rađenih tretmana. Procenat klijanja se kretao od 6,25% do 96,88%, pri čemu je najveći procenat u sva tri tretmana zabeležen na temperaturi od 30°C

Uticaj viline kosice (Cuscuta campestris Yunk.) na fiziološke i anatomske parametre lucerke u uslovima sa i bez primene herbicida

The effects of field dodder on physiological processes and the anatomy of alfalfa plants were examined under controlled conditions. The experiment included the following variants: N - noninfested alfalfa plants (control); I - infested alfalfa plants (untreated); T - infested plants treated with imazethapyr. Imazethapyr application rate was 100 g a.i. ha-1. The following parameters were checked: physiological - pigment content (chlorophyll ɑ, chlorophyll b, total carotenoids); anatomical - stem parameters: thickness of epidermis and cortex, and diameter of stem and central cylinder; leaf parameters: thickness of epidermis, parenchyma and spongy tissue, mesophyll and underside leaf epidermis, and diameter of bundle sheath cells in alfalfa plants. Pigment contents and anatomical parameters were measured: prior to herbicide treatment (0 assessment), then 7 (I assessment), 14 (II assessment), 21 (III assessment), 28 (IV assessment) and 35 (V assessment) days after application (DAA). Field dodder was found to affect the contents of chlorophyll ɑ, chlorophyll ɑ and carotenoids in untreated alfalfa plants, causing significant reductions in pigment content. Conversely, percent reduction in the treated plants decreased 22-5% for chlorophyll ɑ, 25-1%, for chlorophyll b, and 21-11% for carotenoids, while a stimulating effect of 1-6% was observed for the contents of chlorophyll b and carotenoids 35 DAA. Plants infested (untreated) by field dodder had lower values of most anatomical parameters, compared to noninfested plants. The measured anatomical parameters of alfalfa stems and leaves had significantly higher values in noninfested plants and plants treated with imazethapyr than in untreated plants.Uticaj viline kosice na anatomske i fiziološke promene kod biljaka lucerke ispitivan je u kontrolisanim uslovima. Praćene su sledeće varijante: N - nezaražene biljke lucerke (kontrola); I- zaražene biljke lucerke i zaražene biljke lucerke tretirane sa imazetapirom (T). Imazetapir je primenjen u količini od 100 g a.i. ha-1. Mereni su sledeći parametri: fiziološki - sadržaj pigmenata (hlorofil ɑ, hlorofil b i ukupni karotenoidi); anatomski - stablo: debljina epidermisa i primarne kore stabla, prečnik centralnog cilindra i prečnik stabla; list: debljina epidermalnih ćelija lica i naličja lista, debljina parenhimskog i sunđerastog tkiva, debljina mezofila i prečnik ćelija omotača provodnih snopića. Sadržaj pigmenata i anatomski parametri su mereni: pre primene herbicida (0 ocena), potom 7, 14, 21, 35 dana nakon primene herbicida. Vilina kosica je prouzrokovala značajnu redukciju sadržaja pigmenata kod netretiranih biljaka lucerke. Nasuprot ovome, kod tretiranim biljaka lucerke procenat redukcije se smanjivao od 22­5% za hlorofil ɑ, 25-1%, za hlorofil b i 21-11% za karotenoide, dok je za hlorofil ɑ i karotenoide 35 dana nakon primene herbicida zabeležen stimulativni efekat od 1-6%. Biljke zaražene vilinom kosicom (netretirane) su imale značajno manje vrednosti za sve merene anatomske parametare u odnosu na tretirane. Naime, mereni anatomski parametri stabla i lista lucerke su značajno veći kod kontrolnih biljaka i tretitanih sa imazetapirom u odnosu na netretirane

The Impacts of Temperature, Soil Type and Soil Herbicides on Seed Germination and Early Establishment of Common Milkweed (Asclepias syriaca L.)

The effects of different temperatures (20 degrees C, 25 degrees C, 30 degrees C, 35 degrees C and photoperiod 26 degrees C/21 degrees C), types of soil (sand and loam) and soil herbicides (oxyfluorfen, terbuthylazine and mesotrione) on seed germination percentage, germination rate, as well as seedling length and weight of common milkweed (Asclepias syriaca L.) were examined. Over a period of ten days, germinated seeds were counted daily, and seedling length and weight were measured on the final day and germination rate calculated. The results indicated that temperature was the factor that significantly affected the percentage of germinated seeds of common milkweed, seedling length and germination rate, while it had less influence on seedling weight. The results showed that the alternating day/night temperature of 26 degrees C/21 degrees C also had a significant impact as the percentage of germinated seeds was the highest at that temperature on both soil types (sand: 71.3%; loam: 61.3%). Data regarding the herbicides tested (oxyfluorfen, terbuthylazine and mesotrione) showed decreasing germination percentage and seedling length with increasing herbicide concentrations on both soil types. Their effect was weakest on seedling weight. Tested herbicides are usable in control of common milkweed at the stages of germination and early establishment

Uporedna mikro-morfloška i anatomska analiza listova gajenog i hibridne forme korovskog suncokreta (Helianthus annuus)

There are various opinions in the literature on the importance of morpho-anatomical leaf features, such as the number of stomata, the presence of trichomes, cuticle thickness, cell size, leaf thickness, etc. for the susceptibility of plants to foliar herbicides. Knowing that differences in the plant's sensitivity to herbicides may be due to differences in leaf sufrace and inner structure of leaves, a detailed micromorphological and anatomical analysis was performed on the leaves of tolerant and susceptible sunflower forms, both in cultivated hybrids and populations of weedy sunflower. It is interesting that while no significant differences in the number of trichomes and stomata between the resistant and susceptible weedy sunflower populations were observed, in comercial sunflower genotypes these numbers were significantly different. Namely, the number of stomata in the sensitive comercial sunflower hybrid was significantly higher than in the tolerant ones, but the tolerant hybrids had significantly more leaf trichomes than the sensitive one. Consequently, it is possible that the higher density of trichomes makes it impossible for the herbicides to reach the surface of the leaf epidermis, resulting in a reduced uptake. It has also been shown that plants with different levels of herbicide susceptibility also differ in various anatomical parameters.U literaturi postoje oprečna mišljenja o značaju morfo-anatomskih parametara listova, kao što su broj stoma, prisustvo dlaka, debljina kutikule, debljina lista i sl. za osetljivost biljaka prema folijarnim herbicidima. S obzirom na to da razlike u osetljivosti hibrida/populacija prema herbicidima mogu da budu posledica razlika u površinskim strukturama i anatomskoj građi lista, u ovom radu je detaljno analizirana mikro-morfološka i anatomska građa listova tolerantnih i osetljivih formi suncokreta, kako gajenih hibrida tako i populacija hibridnih formi korovskog suncokreta (HFKS). Interesantno je da između rezistentnih i osetljivih populacija HFKS nije bilo statistički značajnih razlika u broju dlaka i stoma na listovima, ali kod hibridnih genotipova jeste. Naime, na naličju lista broj stoma kod osetljivog hibrida je bio statistički značajno veći nego kod tolerantnih, ali su tolerantni hibridi imali statistički značajno više dlaka na listovima od osetljivog, tako da je moguće da veća maljavost onemogućava dospevanje herbicida do površine epidermisa, što za posledicu ima njihovo manje usvajanje. Takođe je pokazano da se biljke različite osetljivosti prema herbicidima razlikuju i u različitim parametrima anatomske građe (debljina palisadnog i sunđerastog tkiva, debljina mezofila i debljina lista)

Common Cocklebur (Xanthium strumarium) Response to Nicosulfuron

The response of two populations (CC1, 43.59 degrees N & 20.40 degrees E; CC2, 44.46 degrees N & 20.17 degrees E) of common cocklebur (Xanthium strumarium L.) to nicosulfuron was investigated both in field experiments and in the laboratory. Population CC1 had no history of treatment with any herbicide, while population CC2 was treated with ALS inhibitor herbicides for six consecutive years. In the field, plants were treated post-emergence with nicosulfuron (0, 10, 20, 40, 60 and 80 g ai ha(-1)) at four true leaves. Visual injury estimation and vegetative parameters (plant height, fresh weight, leaf area) were recorded about month after herbicide application. The acetolactate synthase (ALS) enzyme activity in response to herbicide concentrations of 0, 0.01, 0.1, 1, 10, 100 mu M was determined in vitro. GR(50) values for vegetative parameters and 150 values for ALS activity were slightly greater for the CC2 than for the CC1 population, but the results confirmed that neither population was susceptible to nicosulfuron. Namely, based on results for fresh weight, the population CC1 was about 3.9 and 2.6-fold more susceptible CO nicosulfuron than population CC2 in two consecutive years, but differences were not so prominent for other parameters (plant height, leaf area and ALS activity), ranging from 1.18 to 1.8-fold. The differences between population CC1 and CC2 could be attributed to inter-population variability in susceptibility CO nicosulfuron or could be the consequence of repeated application of ALS herbicides to the CC2 population during the six previous years. Future investigations are necessary in order to clarify this dilemma