Ocena działania olejku jałowcowego (Juniperi aetheroleum) wobec grzybów drożdżopodobnych

Introduction. Juniper has been known and often used in folk medicine since ancient times. The extracts and essential oil of this plant’s fruit exhibit anti-inflammatory, antioxidant, anticancer, blood pressure lowering, antiarthritic, antirheumatic activity and are helpful in Alzheimer’s disease. Fruits contain essential oil (α-pinene, limonene, β-pinene, terpinen-4-ol, sabinene, β-phellandrene, α-terpinene, myrcene, γ-terpinene); organic acids, flavonoids and tannins. Juniper oil shows antimicrobial activity. Aim. The aim of this research was evaluating activity of juniper oil against yeast-like fungi isolated from the oral cavity. Material and methods. The study included 31 strains of fungi belonging to the following species: Candida albicans (14 strains), Candida glabrata (3), Candida guilliermondii (1), Candida humicola (1), Candida kefyr (2), Candida krusei (2), Candida lusitaniae (1), Candida parapsilosis (3), Candida tropicalis (3), Candida utilis (1) and 9 reference strains from genus: C. albicans ATCC 10231, C. glabrata ATCC 66032, C. guilliermondii ATCC 6260, C. kefyr, ATCC 4130, C. krusei ATCC 14249, C. lusitaniae ATCC 34499, C. parapsilosis ATCC 22019, C. tropicalis ATCC 750 i C. utilis ATCC 9958. The susceptibility (MIC) of fungal strains to juniper oil was determined by the method of serial dilution technique in Sabouraud’s agar. At first, the oil was diluted in DMSO, then in distilled water. The tested concentrations were: 20.0, 15.0, 10.0, 7.5 and 5.0 mg/ml. The suspension containing 105 CFU/per drop was transferred by a Steers replicator to the surface of Sabouraud’s agar with or without juniper oil (strains growth control). Incubation was carried out at 37°C for 24-48 hrs under aerobic conditions. The lowest concentration of oil that completely inhibited the growth of the tested yeast-like fungi was taken as the MIC. Results. The results indicated, that the strains of Candida guilliermondii and C. utilis were the most sensitive to juniper oil. The growth of these strains was inhibited at a concentration of 10.0 mg/ml. The 2 species of strains C. glabrata and Candida lusitaniae were sensitive to a concentration of 15.0 mg/ml. The juniper oil was less active against Candida kefyr strains (MIC – 7.5-> 20.0 mg/ml). Fungi from genus of C. krusei, Candida parapsilosis and C. tropicalis were susceptible to concentrations in the range 10.0-≥ 20.0 mg/ml. The Candida albicans strains were characterized by moderate susceptibility. The growth of the 50% strains was inhibited at concentration 15.0 mg/ml and another 50% strains at 20.0 mg/ml. Of all the yeast-like fungi strains tested only 1 strain was sensitive to the low concentration of 7.5 mg/ml, and another 5 strains to 10.0 mg/ml. The growth of 39% of fungi strains was inhibited at the concentration of 15.0 mg/ml and 42% at concentration 20.0 mg/ml of the oil and more. Conclusions. Candida guilliermondii and C. utilis showed the highest sensitivity to juniper oil. The Candida albicans strains were characterized by moderate susceptibility. The juniper oil showed the lowest activity against Candida humicola species.

Blackberry and raspberry are alternative resistance sources to fire blight

Erwinia amylovora causes fire blight mainly on pear, apple and quince trees. This bacterial pathogen also infects other Rosaceous plants, such as blackberry and raspberry. A race structure was established between an isolate of E. amylovora and berries using 40 wild blackberry and 7 wild raspberry genotypes. In pathogenicity tests, wild blackberry and raspberry genotypes had three phenotypic reactions: enhanced susceptibility, moderate susceptibility and resistance. We noted a higher bacterial growth of over 300 × 109 cfu mL-1 in plants with enhanced susceptibility, with resistant genotypes showing a bacterial growth of around 150 × 109 cfu mL-1. These results are also associated with symptoms observed at 29 days post-inoculation. This resistance is being evaluated to control fire blight.

Common milkweed (Asclepias syriaca L.) response to sulcotrione

A laboratory bioassay was conducted to investigate common milkweed response to sulcotrione. Sulcotrione was applied in concentration series of 0.15-0.90 kg a.i./ha without a surfactant and with Dash? at 1 L/ha. Plants grew for 14 days, upon which period morphological (height and fresh weight) and physiological parameters (content of carotenoids, chlorophyll a and chlorophyll b) were measured. Visual crop injury was estimated 7 and 14 days after treatment. Sulcotrione caused leaf bleaching and reduction in pigments content in common milkweed leaves and the degree of change depended on application rates and whether it was applied with or without the surfactant. Inhibition was slightly higher in plants which were treated with a combination of herbicide and surfactant. Based on the findings in this study, common milkweed showed moderate susceptibility to the recommended field rates of sulcotrione.

Genotypic profile of Pantanal creole sheep regarding susceptibility or resistance to scrapie

The objective of this work was to determine the genotypic profile specific to scrapie in codons 136, 154, and 171 of the PRNP gene of the Pantanal creole sheep. Genomic DNA was extracted from blood samples collected from 66 sheep, and the regions of interest on the DNA strand were amplified by PCR. Five haplotypes were identified: ARR, alanine, arginine, arginine; ARQ, alanine, arginine, glutamine; AHQ, alanine, histidine, glutamine; ARH, alanine, arginine, histidine; and VRQ, valine, arginine, glutamine. The most common genotypes were ARQ/ARQ (27%) and ARR/ARQ (24%). The genotypic profile of the Pantanal creole sheep shows low to moderate susceptibility.

NRG010 General Purpose spring wheat

DePauw, R. M., Knox, R. E., Singh, A. K., McCaig, T. N., Clarke, J. M. and Cuthbert, R. D. 2013. NRG010 General Purpose spring wheat. Can. J. Plant Sci. 93: 549–555. Based on 26 trials over 2 yr, the cultivar NRG010 yielded similar to the General Purpose checks Hoffman and AC Andrew. NRG010 had significantly shorter stature than Hoffman. NRG010 had a large white kernel intermediate in size to AC Andrew and Hoffman. NRG010 expressed resistance to prevalent races of leaf rust, stem rust and common bunt, and moderate susceptibility to prevalent races of loose smut and fusarium head blight. NRG010 is eligible for the Canada General Purpose wheat class.

Field susceptibility of 13 scab-resistant apple cultivars to apple powdery mildew [Podosphaera leucotricha (Ell. et Ev.) Salmon]

Field susceptibility of 13 scab-resistant apple cultivars to apple powdery mildew was evaluated in 1983-1986. Four groups of susceptibility were distinguished. None of the 13 tested scab-resistant apple trees exhibited complete field immunity to apple powdery mildew. Two cultivars, 'Prima' and 'Primula', were practically resistant. 'Liberty' and two numbered selections, NY-140-9 and NY-158-2, belonged to the group of lower susceptibility. Moderate susceptibility was shown by: 'Novamac', 'Freedom', 'Gavin', 'Prima' and 'Florina'. The group of apple trees most susceptible to <i>Podosphaera leucotricha</i> included: 'Macfree', 'Priscilla' and 'Nova Easygro'. It is not necessary to use chemical sprays to control powdery mildew on 'Prima' and 'Primula'. A reduced spraying program may be recommended only under high disease pressure on less susceptible apple cultivars. A regular spray schedule is needed on moderately susceptible apple trees, but improved chemical control is necessary on the most susceptible ones.

Susceptibility of Evergreen Azalea Cultivars to Anthracnose Caused by Colletotrichum acutatum

Colletotrichum acutatum is the causal agent of anthracnose on azalea (Rhododendron azalea). This disease was observed in Fall 2002 on ‘Palestrina’ azalea in Italy. Severe outbreaks of this disease were recently observed on several cultivars of azalea grown in nurseries located in the Verbano-Cusio-Ossola Province in the Piedmont region of northern Italy. Information on susceptibility to C. acutatum among azalea cultivars currently grown in Italy was unavailable. Artificial inoculations were performed to evaluate the susceptibility of 70 evergreen azalea cultivars produced in the Lake Maggiore area. Sixty of the cultivars evaluated failed to develop disease symptoms and were considered resistant to C. acutatum. Symptomatic cultivars were placed into three susceptibility classes. The cultivars Addy Wery, Fior di Pesco Cavadini, Geisha Orangerot, Kermesina, Orion, Palestrina, and Snow developed severe anthracnose symptoms. The cultivars Conversation Piece, Eikan, and Martha Hitchcock showed moderate susceptibility.

Relative resistance of newly released apple rootstocks to Phytophthora cactorum

New rootstocks from series SJM (St-Jean-Morden) and SJP84 (ST-Jean-1984) have been evaluated for agronomic qualities since 1970 and 1975, respectively. As a result of the evaluation, seven and nine rootstocks from the SJM and SJP84 series, respectively, were selected. However, these were not evaluated for crown rot resistance. Excised shoot assay was used to evaluate resistance of 22 apple rootstocks to crown rot caused by Phytophthora cactorum (Leb. and Cohn.) Schroet. The pathogenicity of four isolates of P. cactorum to apple rootstocks was confirmed using the same excised twig assay. For both tests, relative lesion length was used as a measure of susceptibility. The analysis of variance showed that there was a significant effect of rootstocks, isolate and the interaction between rootstock and isolate. In general, apple rootstocks were more susceptible to isolate PC04-02 followed by isolates PC04-03 and PC04-01 and less susceptible to isolate PC04-04. The selection SJM189 was the least susceptible to P. cactorum and SJP84-5162 and SJM15 were the most susceptible suggesting that these rootstocks may not be suitable in orchards with favourable conditions to P. cactorum infection. Excised twigs of the SJP84-5180, SJP84-5189, SJP845174, O.3, SJP84-5230, O.3A, SJP84-5198, SJM167 and M.44 showed low to moderate susceptibility, whereas, rootstocks SJP845231, SJM150 and M.26 showed moderate susceptibility to P. cactorum. Rootstocks SJM188, SJP84-5217, MM.111, SJM127, SJP84-5218 and MM.106 showed high susceptibility to P. cactorum. The present results confirmed that none of the released or commercial rootstocks are completely resistant to P. cactorum and an integrated approach including resistance, chemical control and cultural practices is recommended to manage P. cactorum in apple orchards. Key words: Apple breeding, crown rot, Malus domestica Borkh., root rot