Letnik 99 Ljubljana, 2012 Številka 1   Asymbiotic seed germination of Phalenopsis Blume orchids after hand pollination Helena LESAR, Nataša ČERANIČ, Damijana KASTELEC, Zlata LUTHAR Abstract Seven commercial hybrids of Phalaenopsis were included in an asymbiotic germination experiment. Plants differed in size and color of flowers and number of inflorescences and flowers. A total of 109 flowers were included of which 60 or 55% were cross-pollinated and reciprocally pollinated. Seed capsules developed on 46 (76.7%) fertilized flowers. Of these, 38 (82.6%) produced seeds as a result of 19 combinations of cross crossing and 19 combinations of reciprocal crossing. Seeds were surface sterilized using 1.6% dichloroisocyanuric acid and inoculated in Petri dishes on commercial media Sigma P1056, in two repeats. There were 23.7% contaminated Petri dishes with seeds after sterilization. The highest average percentage of protocorms (43.1%) developed in cross crossing of plants 3x7, which statistically significantly differed (p < 0.001) from all other combinations of cross crossing except cross crossing 2x6 (30.6%). Crossing 2x6, 1x6 (8.1%) and 1x5 (5.5%) overlap and there were no statistically significant differences between them. There were no statistically significant differences among all of the remaining crossings. There was an overlap of groups among combinations of cross crossing with small flowers x big flowers and reciprocal crossing of big flowers x small flowers. In successful crossing combinations, first plants with two leaves and one or two roots developed only 80 days after seed inoculation on media. Plant no. 4 with the smallest green-yellow flowers was not compatible with any test plants. Seed capsules without seeds developed when plant 4 was a female plant and flowers just fell off when plant 4 was a male plant.  Key words: Phalaenopsis, crossing, cross crossing, reciprocal crossing, seed, media, morphological stages IZVLEČEK   ASIMBIOTSKA KALITEV ORHIDEJ Phalaenopsis Blume PO ROČNI OPRAŠITVI V poskus asimbiotske kalitve je bilo vključenih 7 komercialnih orhidej iz rodu Phalaenopsis, ki so se razlikovale po velikosti in barvi cvetov ter številu socvetij in cvetov. Skupno je bilo na njih 109 cvetov, od teh je bilo 60 oz. 55% navzkrižno in recipročno oprašenih. Semenske glavice je oblikovalo 46 oz. 76,7% oplojenih cvetov. V 38 oz. v 82,6% semenskih glavicah so nastala semena, kot rezultat 19 kombinacij navzkrižnega in 19 kombinacij recipročnega križanja. Semena so bila površinsko razkužena z 1,6% dikloroizocianurno kislino in inokulirana v dveh ponovitvah na komercialno gojišče Sigma P1056 v petrijevke. Po razkuževanju je bilo okuženih 23,7% petrijevk s semeni. Največji odstotek nastalih protokormov (43,1%) je bil dobljen pri navzkrižnem križanju rastlin 3x7, ta odstotek se statistično značilno (p < 0.001) razlikuje od ostalih kombinacij navzkrižnih križanj, razen navzkrižnega križanja  2x6 (30,6%). Križanja 2x6, 1x6 (8.1%) in 1x5 (5.5%) se prekrivajo in med njimi ni statistično značilnih razlik. Prav tako ni statistično značilnih razlik med ostalimi kombinacijami križanja. Med skupinami navzkrižnih križanj rastlin z malimi cvetovi x rastlin z večjimi cvetovi in recipročnih križanj rastlin z velikimi cvetovi x malimi cvetovi pride do medsebojnega prekrivanja in med njimi ni statistično značilnih razlik. Pri uspešnih kombinacijah križanj so že po 80 dneh inokulacije semen na gojišče nastajale prve rastline z dvema listoma in eno ali dvema koreninama. Rastlina z oznako 4 z najmanjšimi, zeleno rumenimi cvetovi ni bila kompatibilna z nobeno od vključenih rastlin v križanja. V primerih, ko je bila materina rastlina, so nastale semenske glavice brez semen, v primerih, ko je bila očetova rastlina, so cvetovi po oprašitvi odpadli.  Ključne besede: Phalaenopsis, križanje, navzkrižno, recipročno, seme, gojišče, morfološke faze   Selenium supplementation stimulates vegetative and reproductive growth in canola (Brassica napus L.) plants Roghieh HAJIBOLAND and Nasrin KEIVANFAR Abstract Selenium (Se) is a beneficial element for higher plants and its positive effect on plants growth and performance has been reported. Effect of Se under non-stress conditions especially during reproductive phase has not been attracted enough attention. In this work effect of Se supplementation at 0, 10 and 20 μg Se plant-1 was studied in canola (Brassica napus’RGS’) plants during vegetative and reproductive phase of growth under greenhouse conditions. Selenium addition resulted in a significant enhancement of dry matter production of vegetative parts as well as pod and seed dry weight. In addition, Se supplementation caused a considerable acceleration of reproductive events. In vegetative plants, higher photosynthesis rate, carbohydrates and protein content in the leaves was observed in Se treated plants compared with control. Our results suggested beneficial effect of Se on canola seed yield that may also contribute in improving nutritional value of canola for livestock and human.  Key words: flowering, pod dry weight, reproductive phase, seed yield IZVLEČEK   DODATEK SELENA POSPEŠUJE RAST IN REPRODUKCIJO PRI RASTLINAH KANOLE (Brassica napus L.) Selen (Se) je za višje rastline koristen element, znani so njegovi ugodni vplivi na rast rastlin. Pri rastlinah, ki rastejo v nestresnih razmerah, zlasti v reproduktivni fazi razvoja, učinki Se še niso bili ustrezno raziskani. V tem delu so avtorji raziskovali dodatek Se (0, 10 in 20 μg Se na rastlino) pri kanoli (Brassica napus L., cv. RGS) tekom vegetativne in reproduktivne faze. Dodatek Se je povzročil značilno povečanje sušine vegetativnih delov, luskov in semen. Dodatek Se je vplival tudi na pospešitev poteka reprodukcije. Pri rastlinah je bila ugotovljena tudi povečana fotosinteza, večja vsebnost ogljikovih hidratov in beljakovin v listih tretiranih rastlin v primerjavi s kontrolo. Rezultati kažejo na ugoden vpliv Se na pridelek kanole, kar lahko vpliva tudi na izboljšano hranilno vrednost te poljščine za živali in ljudi. Ključne besede: cvetenje, sušina luskov, reproduktivna faza, pridelek semen   Induction of drought tolerance with seed priming in wheat cultivars (Triticum aestivum L.) Alireza Eivazi Abstract Delay in sowing and low precipitation (<300mm annual) in wheat (Triticum aestivum L.) farming is the major problem in the irrigated and rainfall lands of Iran. A factorial experiment for evaluating the effects of seed priming on wheat cultivars was carried out under laboratory, greenhouse and at two field conditions during seasons of 2008-2010. Arrangement of treatments were Zarrin, Shariar, Sardary and Azar cultivars as A factor, and priming treatments including distilled water (DW), osmotic solutions (10% PEG, 2.5% KCl, 4% MN, 10% Urea, 5% NaCl W/V) and plant growth inducers (20 ppm IAA, 1000 ppm CCC) with non-primed seed as a control established B factor. During the second year of field experiment two separate treatments were done under drought stress and well watered conditions. Drought stress was withheld by irrigation at booting stage of plants. Maximum amount of absorbed water was determined in cultivar Shariar, 15.5 g DW. Seed weight of all cultivars increased the most when primed with CCC and IAA. Irrespective of the cultivar seedlings related traits revealed that treatment with CCC increased plumule and radical dry weights (11.5 and 8.0 mg) and their lengths (17.2 and 17.8 cm). In opposite, urea pretreatment had negative effects on seedlings growth. All priming treatments increased grain yield and its components, chlorophyll content and nitrogen absorbed under field and green house conditions in four cultivars in comparison to control. Plants arising from seeds primed with potassium chloride under drought stress had the lowest percentage of variation for traits such as relative water content (-9.3%), total dry matter (-10.7%) and grain yield (-4.0%) in comparison with well watered plants. Potassium chloride improved drought tolerance at all wheat cultivars. There were significant correlations between grain yield at primed with KCl and following wheat traits: number of spikes per square meter (0.91**), number of grains per spike (0.92**) and total dry matter (0.79*). Therefore, it seems that these traits could be used as indirect criteria for selection of high grain yield of cultivars for primed seed.  Key words: drought stress, hydro and osmo priming, plant growth inducers, common bread wheat IZVLEČEK  INDUKCIJA TOLERANCE NA SUŠO S PREDSETVENIM TRETIRANJEM SEMEN PRI IZBRANIH SORTAH PŠENICE (Triticum aestivum L.) Zakasnitev v setvi in majhna količina padavin (<300mm letno) sta glavna problema pri pridelavi pšenice (Triticum aestivum L.) v namakanih in nenamakanih območjih Irana. Izvrednotenje učinka predsetvenega tretiranja semena izbranih sort pšenice je bilo narejeno s faktorskim poskusom v laboratoriju, rastlinjaku in v dveh poljskih poskusih v sezonah 2008-2010. Poskus je bil zastavljen s štirimi sortami pšenice (Zarrin, Shariar, Sardary in Azar) kot faktorjem A in predsetvenimi tretmaji, ki so obsegali destilirano vodo (DW), raztopine osmotikov (0% Urea, 5% NaCl W/V) in rastlinske rastne regulatorje (20 ppm IAA, 1000 ppm CCC) primerjalno z netretiranimi semeni, kar je bila  kontrola in faktor B. V drugem letu poljskega poskusa sta bili opravljeni še obravnavi s sušo in zadostnim zalivanjem. Sušni stres je bil preprečen z zalivanjem v fazi bilčenja. Največ absorbirane vode je bilo izmerjeno pri sorti Shariar, 15.5 g DW. Teža semen vseh sort se je povečala najbolj, kadar so bila semena pred setvijo tretirana s CCC in IAA. Ne glede na sorto se je pokazalo, da sta se suha teža mladega poganjka in korenine (11.5 in 8.0 mg) pri kalicah povečali kot tudi njuni dolžini (17.2 in 17.8 cm) kadar je bilo seme pretretirano s CCC. Nasprotno je imelo predtretiranje z ureo negativni učinek na rast kalic. Vsa predtretiranja so povečala pridelek zrnja in njegove komponente, vsebnost klorofila in privzetje dušika v poskusih v rastlinjaku in poljskem poskusu pri vseh sortah v primerjavi s kontrolo. Rastline, ki so zrasle iz semen predtretiranih s KCl v razmerah sušnega stresa so imele najmanjši odstotek variabilnosti v znakih kot so reletivna vsebnost vode (-9.3%), celokupna suha snov (-10.7%) in pridelek zrnja (-4.0%) v primerjavi z dobro zalivanimi rastlinami. Natrijev klorid je pri vseh sortah pšenice izboljšal prenašanje suše. Ugotovljene so bile značilne korelacije med pridelkom zrnja pšenice, ki je bila predtretirana s KCl in naslednjimi znaki pridelka: število klasov na kvdratni meter (0.91**), število zrn na klas (0.92**) in celokupno suho snov (0.79*). Zato izgleda, da bi lahko te znake uporabili kot posredni kriterij za izbor visokoproduktivnih sort pšenice, pri katerih se seme predtretira.  Ključne besede: sušni stres, vodno in osmotsko predtretiranje semen, rastlinski rastni regulatorji, krušna                                 pšenica   Influence of NaCl treatments on growth and biochemical parameters of castor bean (Ricinus communis L.) Mohsen JANMOHAMMADI, Amin ABBASI, Naser SABAGHNIA Abstract Castor bean (Ricinus communis L.) is widely cultivated throughout the world for use as a medicinal plant and oil consumption purposes; however its salt tolerance has not been clarified. To investigate the effect of salt stress on its growth and on activity of antioxidative enzymes in different organs, castor bean plants at the 4-leaf stage were subjected to 50, 100 and 200 mM NaCl admixed to Hoagland’s solution for 10 days under greenhouse conditions. The results showed that salt stress inhibited plant growth (root and shoot length, fresh root and shot weight) but root growth was more affected then shoot. Relative water content of leaves and the membrane stability of the leaves were decreased with increasing NaCl concentration. The activity of guaiacol peroxidase (GPX) and catalase (CAT) was sharply decreased by escalation of salt stress. However activity of ascorbate peroxidase (APX) was enhanced under moderate salt stress (100 mM NaCl) in both root and shoot but then decreased with increased NaCl concentration. The activity of superoxide dismutase (SOD) increased with the increase of the concentration of NaCl in shoots and root. However alternation in enzymatic antioxidant activity was noticed in shoot compared to root. Increased H2O2, total soluble protein, proline content and malondialdehyde (MDA) concentration in both plant’s organs was linearly and positively correlated with increasing NaCl concentration. The results of this study suggest that the salt sensitivity of Castor bean plant under salt stress conditions is probably due to a lack of efficient activity of CAT and GPX probably lead to imperfect H2O2 scavenging. Keywords: Castor bean, salt stress, oxidative stress, APX, CAT, H2O2, lipid peroxidation, MDA IZVLEČEK  VPLIV TRETMAJA Z NaCl NA RAST IN BIOKEMIČNE PARAMETRE NAVADNEGA KLOŠČEVCA (Ricinus communis L.) Navadni kloščevec (Ricinus communis L.) se v svetovnem merilu pogosto goji kot zdravilna rastlina ali zaradi uporabnega olja, njegova toleranca na solni stres pa še ni bila raziskana. Za preučevanje vpliva solnega stresa na rast in aktivnost antioksidacijskih encimov smo navadni kloščevec izpostavili v razvojni fazi 4 listov koncentracijam NaCl 50, 100 in 200 mM, raztopljenih v Hoaglandovi raztopini in rastline gojili deset dni v rastlinjaku. Rezultati so pokazali, da je solni stres inhibiral rast rastlin (dolžino korenin in poganjkov in njihovo svežo težo), vendar je bila rast korenin bolj inhibirana. Relativna vsebnost vode in integriteta membran listnega tkiva sta upadali z naraščajočo koncentracijo NaCl. Aktivnost gvajakol peroksidaze (GPX) in katalaze (CAT) je močno upadla po povečanju solnega stresa. Aktivnost askorbat peroksidaze (APX) se je povečala v razmerah zmernega solnega stresa (100 mM NaCl) v koreninanh in poganjku, vendar je s povečevanjem koncentracije NaCL potem upadla. Aktivnost superoksid dismutaze (SOD) se je s povečevanjem koncentracije NaCl povečevala v koreninah in poganjku. Kljub temu je bilo v poganjku opaziti večje spremembe v encimatski antioksidacijski aktivnosti v primerjavi s koreninami. Vsebnost H2O2, celokupnih topnih proteinov, prolina in malondialdehida (MDA) se je v obeh organih linearno povečevala z naraščajočo koncentracijo NaCl. Rezultati te raziskave kažejo, da je občutljivost navadnega kloščevca na solni stres posledica nezadostne aktivnosti encimov CAT in GPX, kar verjetno vodi do nepopolne presnove H2O2.  Ključne besede: navadni kloščevec, solni stres, oksidacijski stres, APX, CAT, H2O2, peroksidacija lipidov, MDA Water and nitrogen use efficiency of common ragweed (Ambrosia artemisiifolia L.) at different nitrogen and water levels Robert Leskovšek, Klemen Eler, Franc Batič, Andrej Simončič Abstract Common ragweed (Ambrosia artemisiifolia L.) spread across Europe and other regions is becoming a serious health and economic threat. A pot experiment was conducted in 2011 to determine effect of various nitrogen (N) (10, 100 kg/ha) and water supply regime on resource use efficiency of ragweed. Ragweed plants increased their dry matter production with increased water and N availability. Nitrogen use efficiency (NUE) was decreased with N addition and was not influenced by water availability. Mean nitrogen residence time (MRT) was longer at low N and water levels. In contrast, nitrogen productivity (NP), NUE and water use efficiency (WUE) were all increased with enhanced water supply. A trade-off between parameters of NUE was attributed to differential response of NP and MRT to soil fertility and water supply. Our results confirmed that ragweed displayed high adaptation to unproductive sites. However, ragweed’s greater plasticity in response to water availability compared to N availability suggest, that water supply plays important role in its invasion success and in combination with disturbance ragweed might further spread into more productive environments.  Key words: Ambrosia artemisifolia, invasivity, water use efficiency, nitrogen use efficiency, pot experiment, Slovenia IZVLEČEK UČINKOVITOST IZRABE VODE IN DUŠIKA PRI PELINOLISTNI AMBROZIJI (Ambrosia artemisiifolia L.) OB RAZLIČNIH RAVNEH DUŠIKA IN VODE Pelinolistna ambrozija (Ambrosia artemisiifolia L.) postaja s svojim nezadržnim širjenjem po Evropi in drugih regijah sveta resen ekonomski in zdravstveni problem. Za določitev učinkovitosti izrabe virov je bil v letu 2011 zasnovan lončni poskus z dvema obravnavanjema z dušikom (N) (10 in 100 kg/ha) in vodo (veliko, malo vode). Pelinolistna ambrozija je povečala produkcijo suhe mase pri večjih odmerkih dušika in vode. Učinkovitost izrabe dušika (NUE) se je pri večjem odmerku dušika statistično značilno zmanjšala, preskrba z vodo pa ni imela vpliv na NUE. Srednji čas zadrževanja dušika v rastlini (MRT) je bil daljši pri manjših odmerkih dušika in manj vode. Nasprotno so se produktivnost dušika (NP), NUE in učinkovitost izrabe vode (WUE) pri večji dostopnosti vode povečali. Kompromis med faktorji NUE je bil pripisan različnemu odzivu NP in MRT na preučevane dejavnike dušika in vode, pri čemer je bil odziv pelinolistne ambrozije pri različnih odmerkih vode bolj plastičen v primerjavi z različnimi odmerki dušika. Naši rezultati so potrdili, da je pelinolistna ambrozija prilagojena na neproduktivna rastišča, vendar nakazujejo, da ima voda velik vpliv pri invazivnem uspehu pelinolistne ambrozije in bi se, glede na izkazano plastičnost, v motenih okoljih lahko razširila tudi v bolj produktivna rastišča.  Ključne besede: Ambrosia artemisifolia, invazivnost, učinkovitost izrabe vode, učinkovitost izrabe dušika, lončni poskus, Slovenija    Pesticide residues in samples of apples, lettuce and potatoes from integrated pest management in Slovenia from 2005-2009  Helena BAŠA ČESNIK, Špela VELIKONJA BOLTA, Ana GREGORČIČ Abstract In the period from 2005 to 2009 225 samples of apples, lettuce and potatoes from Slovene producers included in integrated pest management (IPM) were analysed for plant protection product (PPP) residues. The samples were analysed for the presence of more than 200 different active compounds using four analytical methods. In 38.7% of apple samples residues were not detected, 58.6% of apple samples contained residues lower than or equal to Maximum Residue Levels (MRLs) while 2.7% of apple samples exceeded MRLs. In 84.6% of lettuce samples residues were not detected, 12.3% of lettuce samples contained residues lower than or equal to MRLs while 3.1% of lettuce samples exceeded MRLs. In 98.0% of potato samples residues were not detected, 2.0% of potato samples contained residues lower than or equal to MRLs and no potato samples exceeded MRLs. Multiple residues were found only in apples and lettuce. The trend observed during the years was the decrease of sample portion of samples containing multiple residues in apples from 2005 to 2008. The most frequently found active substance in apples and lettuce was dithiocarbamates. In potato only phosalone was found.  Key words: apples, lettuce, potatoes, integrated pest management, plant protection product residues, GC/MS,                       LC/MS/MS IZVLEČEK OSTANKI PESTICIDOV V VZORCIH JABOLK, SOLATE IN KROMPIRJA V INTEGRIRANI PRIDELAVI V SLOVENIJI V LETIH 2005-2009 V obdobju od 2005 do 2009 smo na ostanke fitofarmacevtskih sredstev (FFS) analizirali 225 vzorcev jabolk, solate in krompirja slovenskih proizvajalcev vključenih v integrirano pridelavo (IP). Vse vzorce smo analizirali s štirimi analitskimi metodami na prisotnost več kot 200 različnih aktivnih spojin. V 38,7% vzorcev jabolk ostankov nismo določili, 58,6% vzorcev jabolk je vsebovalo ostanke manjše ali enake maksimalnim dovoljenim količinam ostankov (MRL) medtem ko je 2,7% vzorcev jabolk preseglo MRL vrednosti. V 84.6% vzorcev solate ostankov nismo določili, 12,3% vzorcev solate je vsebovalo ostanke manjše ali enake MRL vrednostim medtem ko je 3,1% vzorcev solate preseglo MRL vrednosti. V 98,0% vzorcev krompirja ostankov nismo določili, 2,0% vzorcev krompirja je vsebovalo ostanke manjše ali enake MRL vrednostim in nobeden vzorec krompirja ni presegel MRL vrednosti. Ostanke dveh ali več aktivnih spojin smo določili le v jabolkih in solati. Trend, ki smo ga opazili tekom let je, da delež vzorcev, ki vsebujejo ostanke dveh ali več aktivnih spojin v jabolkih, pada od leta 2005 do 2008. Najpogosteje najdena aktivna snov v jabolkih in solati je ditiokarbamati. V krompirju smo določili le fosalon. Ključne besede: jabolka, solata, krompir, integrirana pridelava, ostanki fitofarmacevtskih sredstev, GC/MS,                              LC/MS/MSC/MS/MS   Compatibility of selected herbicides with entomopathogenic fungus Beauveria bassiana (Bals.) Vuill Franci Aco CELAR, Katarina KOS Abstract 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.  Key words: Beauveria bassiana, herbicides, inhibition, mycelial growth, compatibility IZVLEČEK Kompatibilnost izbranih herbicidov z entomopatogeno glivo Beauveria bassiana (Bals.) Vuill 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.  Ključne besede: Beauveria bassiana, herbicidi, inhibicija, rast micelija, kompatibilnost In vitro plant regeneration of Indian jujube (Ziziphus mauritiana Lamk.) cv. Zaytoni via indirect organogenesis Majid Abdel Ibrahim, Abbas Mehdi Jasim and Muayed Fadhil Abbas Abstract In vitro plant regeneration was achieved in Ziziphus mauritiana Lamk., through de novo formation of meristems in callus obtained from the shoot tip cultured on MS medium supplemented with either IBA (10.0 mg.l-1) or NAA (15.0 mg.l-1) and 5.0 mg.l-1 BA. Organogenic callus was obtained when the primary callus was cultured on MS medium supplemented with BA at 5.0 mg.l-1 .Adventitious shoots were obtained when the organogenic callus was incubated on MS medium supplemented with BA at 1.0 mg.l-1 and NAA at 0.1 mg.l-1. Whole plants were developed when the adventitious shoots were transferred to half strength MS medium supplemented with NAA at 0.2 mg.l-1.  Key words:  Ziziphus mauritiana Lamk., adventitious shoots, shoot tip explants IZVLEČEK IN VITRO REGENERACIJA INDIJSKE ŽIŽOLE (Ziziphus mauritiana Lamk.) CV. ZAYTONI S POSREDNO ORGANOGENEZO In vitro regeneracija poganjkov je bila dosežena pri indijski žižoli (Ziziphus mauritiana Lamk.) iz meristemskih izsečkov preko kalusa na MS gojišču z dodatkom bodisi hormona IBA (10,0 mg l-1) ali NAA (15,0 mg l-1) in 5.0 mg l-1 BA. Organogeni kalus je bil dobljen, ko se je primarni kalus prestavilo na MS gojišče z dodatkom 5,0 mg l-1 hormona BA. Adventivni poganjki so nastali iz organogenega kalusa, ki je bil gojen na MS gojišču z dodatkom hormonov BA (1.0 mg l-1) in NAA (0.1 mg l-1). Adventivne poganjke se je koreninilo na polovični koncentraciji MS gojišča z dodatkom hormona NAA (0.2 mg l-1).  Ključne besede:  žižola, Ziziphus mauritiana Lamk., meristemski izsečki, adventivni poganjki   Acclimatization of terrestrial orchid Bletilla striata Rchb.f. (Orchidaceae) propagated under in vitro conditions Helena LESAR, Barbara HLEBEC, Nataša ČERANIČ, Damijana KASTELEC, Zlata LUTHAR Abstract Bletilla striata is a terrestrial sympodial orchid. Substrates used for outdoor growing, differing in the mixture of added components and nutrients, were chosen for acclimatization of the asymbiotic propagated plants. A total of 651 Bletilla striata orchids were planted in 3 commercial substrates: ″Tonsubstrat″ (Ton), ″Baltisches substrat″ (Baltski) and ″Royal-Garden″ (Royal). Prior to acclimatization, the plants were 2.5 cm on average, with at least 2 leaves and 2 - 3 cm long root or roots. Fewest plants (3.1%) died in Ton substrate, 3.2% in Baltski substrate and 5.0% in Royal substrate. There were no statistically significant differences among substrates (p = 0.558) in the percentage of plants that died. Substrates used in combination with the chosen phenophase and established conditions were suitable for acclimatization of Bletilla striata orchids, whereby 95-97% of plants successfully adapted from heterotrophic to autotrophic conditions in a very short period of two months. The basic conditions for success are that plants are large and vital enough prior to acclimatization, that the substrate is appropriate and that appropriate conditions of relative humidity, temperature, light and ventilation without major fluctuations of these factors are ensured during acclimatization.  Key words: ornamental orchid, Bletilla striata, tissue culture, acclimatization, substrate, growth, development IZVLEČEK  AKLIMATIZACIJA TERESTIČNE ORHIDEJE Bletilla striata Rchb.f. (Orchidaceae) RAZMNOŽENE V in vitro RAZMERAH Bletilla striata je simpodialno razraščajoča se, v tleh rastoča orhideja. Za aklimatizacijo asimbiotsko razmnoženih rastlin smo izbrali substrate, ki se uporabljajo za gojenje rastlin na prostem ter se razlikujejo glede mešanice dodanih komponent in hranil. Skupno je bilo posajenih 651 orhidej v 3 komercialne substrate, ″Tonsubstrat″ (Ton), ″Baltisches substrat″ (Baltski) in ″Royal-Garden″ (Royal). Pred aklimatizacijo so imele rastline v povprečju 2,5 cm velik nadzemni del z vsaj dvema listoma in 2 do 3 cm dolgo korenino oz. korenine. Najmanj (3,1%) rastlin je propadlo v postopku aklimatizacije v Ton substratu, 3,2% v Baltskem substratu in največ 5,0% v Royal substratu. Med substrati ni bilo statistično značilnih razlik (p = 0,558) v odstotku propadlih rastlin med aklimatizacijo. Uporabljeni substrati v kombinaciji z izbrano fenofazo in vzpostavljene razmere so zelo primerni za aklimatizacijo te orhideje  saj se je 95 do 97% rastlin uspešno prilagodilo iz heterotrofnih na avtotrofne razmere in to v zelo kratkem obdobju dveh mesecev. Osnovni pogoj uspeha je, da so in vitro rastline pred aklimatizacijo dovolj velike in vitalne, primeren substrat ter ustrezne razmere, vlaga, temperatura, svetloba in kroženje zraka, brez večjih nihanj v obdobju aklimatizacije.  Ključne besede: okrasna orhideja, Bletilla striata, tkivna kultura, aklimatizacija, substrat, rast, razvoj   Antraknoza pri ameriških borovnicah (Vaccinium corymbosum L): povzročitelji in epidemiologija bolezni Alenka MUNDA IZVLEČEK Antraknoza sodi med najpomembnejše glivične bolezni gojenih borovnic. Prizadene predvsem plodove: v času zorenja in med skladiščenjem se značilno zgubajo in zmehčajo, prekrijejo jih oranžne sluzaste gmote trosov. V letih 2005 - 2009 smo v nasadih ameriških borovnic na Ljubljanskem barju zbrali 33 primerkov simptomatičnih rastlin. S standardnimi mikroskopsko morfološkimi in molekulskimi tehnikami smo ugotovili, da je povzročiteljica antraknoze pri ameriških borovnicah gliva Colletotrichum fioriniae. S sukcesivno izolacijo iz naravno okuženih ameriških borovnic smo ugotovili, da je gliva C. fioriniae navzoča tekom vse rastne dobe. Izolirali smo jo tako iz organov in tkiv z izraženimi bolezenskimi znamenji kot tudi iz navidezno zdravih. Potrdili smo, da gliva prezimi v poganjkih z odmrlimi vršički ter v ostankih pecljevine, pa tudi v navidezno zdravih poganjkih in brstih. Brsti, zlasti rodni, so poleg poganjkov z odmrlimi vršički in ostankov pecljevine najpomembnejši vir primarnega inokuluma.  Ključne besede: ameriška borovnica, antraknoza, Colletotrichum fioriniae ABSTRACT ANTRACNOZE IN AMERICAN BLUBERRY (Vaccinium corymbosum L): FUNGUS AND EPIDEMIOLOGY OF DISEASE Anthracnose is one of the most important fungal diseases of cultivated blueberries. It mainly affects fruits and causes rotting of ripe fruit both before harvest and during storage. Infected blueberries become wrinkled, soft and covered with slimy orange conidial masses. In the years 2005 -2009 we collected 33 samples of symptomatic plants from high-bush blueberry plantations in the Ljubljana Wetland. Using standard morphological and molecular methods we identified Colletotrichum fioriniae as the causative agent of the disease. Successive isolations from naturally infected high-bush blueberry bushes revealed the presence of C. fioriniae during the entire growing season. It was consistently isolated from symptomatic as well as from symptomless tissues. We confirmed that the fungus overwinters in canes with dead tips and fruit spurs and also in symptomless canes and buds. Buds, particularly flower buds, appear to be the most important source of primary inoculum apart from canes with dead twigs and fruits spurs. Key words:    high-bush blueberry, anthracnose, Colletotrichum fioriniae   Analiza EST klonov križancev Coffea arabica X Coffea canephora in Coffea canephora X Coffea congensis Tina SVETEK, Nataša ŠIBANC izvleček EST ali oznake izraženih zaporedij so DNA zaporedja, dolga od 100 do 800 baznih parov, pridobljena z eno reakcijo določanja nukleotidnega zaporedja cDNA molekulam iz 5’ ali 3’ smeri. Vsebujejo prepisana, ne nujno pa tudi prevedena, zaporedja genov ter pogosto tudi elemente vektorjev. Predstavljajo presežen nabor izraženih genov v nekem vzorcu in se uporabljajo za študije izražanja genov, iskanje novih genov, raziskave alternativnega izrezovanja intronov idr. Mnogokrat predstavljajo prvo orodje funkcionalne genomike manj raziskanih organizmov. Zaradi presežnosti se jih mnogokrat združuje v gruče. Največjo zbirko EST zaporedij vzdržuje NCBI, imenuje se dbEST in ima več kot 70 milijonov zaporedij. V omenjeni bazi smo poiskali klone EST dveh križancev kave, Coffea arabica X Coffea canephora ter Coffea canephora X Coffea congensis, ter s pomočjo BLAST algoritma poiskali katere proteine kodirajo. Najdenim proteinom smo nato določili ontologijo.  Ključne besede: EST, Coffea arabica X Coffea canephora, Coffea canephora X Coffea congensis, BLAST, ontologija, bioinformatika abstract EST CLONE ANALYSIS OF TWO COFFEE HYBRIDS (Coffea arabica X Coffea canephora and Coffea canephora X Coffea congensis) Expressed sequence tags (ESTs) are short (from 100 to 800 base pairs) 5' or 3' sequences that are acquired with single pass sequencing of cDNA molecules. They contain transcribed, but not necessarily translated regions of genes and often also vector elements. They represent a redundant set of expressed genes in a given sample and are used in gene expression studies, finding new genes, alternative splicing research etc. ESTs often represent primary tool of functional genomic of orphan crops. They are often clustered due to their redundancy. The largest EST collection named dbEST, it is maintaned by NCBI and contains more than 70 million sequences. In this database, we have searched for EST clones of two coffee hybrids, Coffea arabica X Coffea canephora and Coffea canephora X Coffea congensis, and used BLAST algorithm to find out which proteins they are encoding. We have also determined gene ontology of protein hits.  Key words:  EST, Coffea arabica X Coffea canephora, Coffea canephora X Coffea congensis, BLAST, ontology, bioinformatics Japonski dresnik (Fallopia japonica [Houtt.] Ronse Decraene) in njegovo zatiranje z bolšico Aphalara itadori Shinji Žiga LAZNIK, Stanislav TRDAN izvleček Evropska agencija za okolje je sestavila seznam 163 najpomembnejših invazivnih organizmov, ki ogrožajo ekosisteme v Evropi. Med njimi je tudi rastlinska vrsta japonski dresnik (Fallopia japonica), ki uspeva na različnih tipih tal. Najhitreje poseljuje ruderalna rastišča, vendar postaja zaradi njegove izredne konkurenčnosti vse pomembnejši člen ekosistemov, kjer izpodriva samonikle rastlinske vrste. Mehansko odstranjevanje japonskega dresnika s košnjo je le začasna rešitev, saj ga na takšen način ne zatremo. Ker se ta rastlinska vrsta razrašča v urbanih območjih in ob vodah, številni strokovnjaki menijo, da predstavlja dolgoročno rešitev le biotično zatiranje tega plevela, in sicer z vnosom njegovega naravnega sovražnika iz okolja, od koder izvira tudi omenjena invazivna vrsta. Na Japonskem ima japonski dresnik okoli 180 različnih naravnih sovražnikov, a le bolšici Aphalara itadori pripisujejo gospodarski pomen. Največjo škodo s sesanjem rastlinskega soka na japonskem dresniku povzročajo najmlajše nimfe. Napadene rastline sicer ne propadejo, vendar je njihova rast omejena. V Veliki Britaniji, ki je prvo ozemlje v Evropi, kamor so vnesli omenjeno bolšico, so potrdili zmožnost njenega preživetja na prostem tudi pozimi. Vnos bolšice Aphalara itadori z namenom zatiranja japonskega dresnika je tako v Evropi kot v svetu prvi zgled klasičnega biotičnega zatiranja plevelov.  Ključne besede: japonski dresnik, Fallopia japonica, škoda, klasično biotično varstvo, Aphalara itadori abstract DAMAGE POTENTIAL OF JAPANESE KNOTWEED (Fallopi japonica) AND ITS BIOLOGICAL CONTROL WITH PSYLLID Aphalara itadori SHINJI European Environment Agency composed the list of 163 most important invasive organisms, that are threatening European ecosystems. One of above mentioned invasive species is also the plant Japanese knotweed (Fallopia japonica), which grow on different soil types. In ruderal habitats the plant is most prevalent, however because of its competitive position the Japanese knotweed is becoming more and more important part of the ecosystems, because it is superseding indigenous species. Mechanical removal is only temporary solution of its extermination. While this plant species grows in urban areas and near the water, numerous researchers see the long-term solution of its extermination in biological control of this weed with introduction of natural enemy from its origin. In Japan Japanese knotweed has about 180 different natural enemies but only the psyllid Aphalara itadori has been prooved to be effective. Young larvae are the most damaging stage of the insect. With sucking of the plant juice, plant is not destroyed, it only develops slower. In Great Britain, which is the first area in Europe, where the above mentioned psyllid was introduced, species also overwinters in the open. The introduction od Aphalara itadori represent the first example of classical biological control of weeds not only in Europe but also worlwide.  Key words: Japanese knotweed, Fallopia japonica, damage, biological control, Aphalara itadori Značilnosti diatomejske zemlje kot naravnega insekticida za zatiranje skladiščnih škodljivcev Helena ROJHT, Aleksander HORVAT, Stanislav TRDAN izvleček Diatomejsko zemljo uporabljajo v številne namene, med drugim tudi kot bioinsekticid za varovanje uskladiščenih pridelkov. Ta zemlja nastane z mletjem sedimentnih kamnin, imenovanih diatomiti. Obstaja veliko vrst diatomejske zemlje, a le zemlje z manj kot 7 % kristalnega SiO2 so primerne za zatiranje škodljivcev. Diatomejska zemlja ni toksična za sesalce, dolgotrajno varuje živež pred škodljivimi žuželkami, za njen nanos se uporablja približno enaka tehnologija kot pri klasičnem nanosu insekticidov in se med predelavo zlahka odstrani z živeža. Med nekaj negativnimi lastnostmi gre izpostaviti dejstvo, da zmanjša hektolitrsko maso zrnja (zniža nasipno gostoto zrnja), ki je glavno merilo kakovosti zrnja. Diatomejska zemlja ima velik absorpcijski potencial in se veže na epikutikularne voske žuželk, zato deluje praktično na vse škodljivce, ki imajo kutikulo zaščiteno z voski.  Ključne besede: diatomejska zemlja, insekticidno delovanje, skladiščni škodljivci, uskladiščeni pridelki ABSTRACT CHARACTERISTICS OF DIATOMACEOUS EARTH AS BIOPESTICIDE FOR CONTROL OF STORED PESTS Diatomaceous earth is used for many purposes, including as a bioinsecticide for protection of stored crops. This material is produced by milling the sedimentary rock called diatomite. There are many types of diatomaceous earth but only diatomaceous earths with less than 7% of crystalline silica are suitable for pest control. Diatomaceous earth is not toxic to mammals, it provides the protection of food on a long-term against harmful insects, and for its application it is used around the same technology as in the conventional application of insecticides and is easily removed during processing. Among some of the negative characteristics is that reduces bulk density of grain, which is the main criterion of assessing the quality of grain. Diatomaceous earth has a high absorption potential and is bound to insect epicuticular waxes, and act practically on all pests that have cuticula protected by wax.  Kwy words: diatomaceous earth, insecticidal activity, stored pests, stored products