bluuebunny/crossref_metadata_2025_split huggingface dataset:
Priming responses of leek (Allium porrum L.) seeds to different dissolved oxygen levels in the osmoticum
Authors: BUJALSKI W. , NIENOW A. W. , MAUDE R. B. , GRAY D. 
Published: February 2008

SummaryLeek seeds (Allium porrum L.) cv. Winterreuzen were treated for 5 days in stirred bioreactors containing a ‐1.0 MPa polyethylene glycol (PEG 6000) solution. The level of dissolved oxygen was controlled from zero to approximately two and a half times that of saturation with respect to atmospheric air by bubbling through 02/N2 gas blends from 0% O2 to 50% O2. The treatment with 0% O2 (i.e. bubbling with N2) gave no reduction in germination time compared to untreated seeds after allowing for the time for water imbibition. As the proportion of oxygen was increased, a rapid reduction was observed until a concentration equivalent to air was used. Further increases to the maximum, produced only a marginal further improvement. The reduction in germination times for seeds that had been cabinet dried was longer for all treatments due to the time required for re‐imbibition of water but the general response to priming was the same as with undried seeds. Only dried seeds treated with air or higher oxygen concentrations showed enhanced synchronicity of germination times. The percentage germination of seeds from all treatments was the same, including the treatment with nitrogen gas. These tests help to explain the recently reported advantages of using enriched air for seed priming and are one of the necessary protocols for ensuring satisfactory bulk priming.
Physiological and developmental aspects of increased plant growth in solarised soils
Authors: GRUENZWEIG J. M. , RABINOWITCH H. D. , KATAN J. 
Published: February 2008

SummarySoil solarisation enhances plant growth even in the absence of known major pathogens. This phenomenon is known as increased growth response (IGR). Corn, cucumber, sorghum, tobacco and tomato plants under controlled conditions revealed distinct IGR in solarised soil as compared to control non‐treated soil. IGR was recorded in shoots of tomato (Lycopersicon esculentum Mill. cv. Rehovot 13) seedlings, 15 days after transplanting and in roots only two weeks later. Detailed studies on the third true tomato leaf showed significantly higher levels of chlorophyll and protein contents in plants from solarised soil as compared to those from the control. In addition, the degradation of these compounds, decrease of net photosynthesis at near‐saturation light intensity and of photochemical yield with ageing were delayed in plants growing in solarised soil as compared to the control. The ratio of variable to maximal chlorophyll fluorescence was independent of soil treatment and was comparable to normal levels measured in other plants. Therefore, no apparent environmental stress seems to be involved in either of the soil‐plant systems. It is concluded that the initial IGR in solarised soil is independent of improved root growth. Delayed leaf senescence appeared to be a plant response contributing to IGR.
Comparative studies of the quality of fresh and stored mushrooms of Agaricus bisporus with two tropical Agaricus bitorquis strains
Authors: SMITH J. F. , LOVE M. E. , BURTON K. S. 
Published: February 2008

SummaryThree white strains of mushroom were grown for quality assessment tests, a commercial Agaricus bisporus strain SOMYCEL U3 currently popular in most major mushroom producing countries and two tropical Agaricus bitorquis strains, ATCC 32675 and AGC W20. Mushrooms were harvested as stage 2 mushrooms (closed buttons with universal veil intact) and stored at 18°C (± 0.5°C) for 5 days during which time colour development, the rate of fruitbody maturation and weight loss were assessed. Throughout the storage period, a reflectance colormeter was used to monitor colour changes on the tops and sides of mushroom fruitbodies.The tops of both A. bitorquis strains were significantly more yellow than the A. bisporus strain, whereas the sides were significantly less yellow. Overall, the A. birorquis strain AGC W20 was clearly the least discoloured and least yellow at the time of harvest. Although all the three strains tested gave similar fresh weight losses during storage, i.e. approximately 10% per day, ATCC 32675 exhibited a very slow maturation rate. Both U3 and AGC W20 matured at a similar much faster rate forming open cups within the 5 day storage period. ATCC 32675 also showed the least increase in the degree of discolouration with time, whether readings were taken from the sides or tops of mushrooms. A breeding programme to combine the most salient features of AGC W20 (an intensely white mushroom at harvest, high yielding with distinct flush pattern) and ATCC 32675 (very slow maturation rate during storage) is suggested.
Ultra‐violet radiation damage to Metarhizium flavoviride conidia and the protection given by vegetable and mineral oils and chemical sunscreens
Authors: MOORE D. , BRIDGE P. D. , HIGGINS P. M. , BATEMAN R. P. , PRIOR C. 
Published: February 2008

Summary Metarhizium flavouiride conidia formulated in oil or water were exposed to simulated solar radiation. Radiation below 320 nm killed conidia and caused delays in the germination of survivors; germination was greater after 48 h of incubation than after 24 h. UV exposure of conidia formulated in oil for 2 h reduced germination from 99% to 37.5% after incubation for 48 h. Exposure of conidia in water to UV for 1 h resulted in 4.7% germination after 24 h incubation compared with 36.5% for conidia formulated in oil. The addition of 1% oxybenzone resulted in 81.9% conidial germination after 3 h exposure and 48 h incubation compared with 28.1% in oil without the sunscreen.
Application of Metarhizium anisopliae (Metsch.) Sor. conidia to control Otiorhynchus sulcatus (F.) (Coleoptera: Curculionidae) larvae on glasshouse pot plants
Authors: MOORHOUSE E. R. , GILLESPIE A. T. , CHARNLEY A. K. 
Published: February 2008

SummaryThe efficacy of the entomogenous fungus Metarhizium anisopliae was assessed against vine weevil (Otiorhynchus sulcatus) larvae in the glasshouse. Prophylactic application of M. anisopliae conidia to begonia resulted in total larval control, but curative applications were less effective with only 65% control when conidial application was delayed until 8 weeks after egg infestation. Prophylactic applications also provided effective larval control on begonia plants which received multiple egg applications over a six week period. Larval mortality was monitored on cyclamen plants which had received a prophylactic drench of M. anisopliae conidia. The population was reduced by 78% within 5 weeks of egg application and control rose to 90% after 17 weeks, although the increase was not significant. Prophylactic conidial drenches were compared with a similar number of compost incorporated conidia on cyclamen, but there was no significant difference between the two spore application strategies. Application of M. anisopliae conidia to impatiens modules before potting‐on resulted in over 89% larval control compared to over 97% control when a similar number of conidia were applied to the plants after potting. Larval control was further reduced to 79% when the module drenches were reduced to one quarter of the highest dose (5 × 107 compared to 2 × 108 conidia per module). The persistence of three M. anisopliae strains was examined over a 20 week period on impatiens. There was no overall decline in efficacy over this period, although there was variability in the performance of the different strains and it was suggested that this was linked to temperature. The results of these experiments suggest that M. anisopliae has considerable potential as a microbial control agent for O. sulcatus on glasshouse ornamentals.
The effect of cereal break crops on barley mild mosaic virus
Authors: ADAMS M J , JONES D R , O'NEILL T M , HILL S A 
Published: February 2008

SummaryThe effects of growing one, two or three years of resistant barley or winter wheat on barley mild mosaic virus were studied in experiments on two naturally‐infested sites in Gloucestershire and Cambridgeshire. Disease incidence and yield of the susceptible cultivars Igri and Maris Otter following a three year break were not significantly different from those of control plots that had grown continuous susceptible barley. The effects of cropping sequence treatment on soil populations of the fungus vector, Polymyxa graminis, were assessed by estimating most probable numbers of propagules following bioassays. Variability was large and neither total numbers of propagules, nor those carrying virus, was significantly affected by the cropping treatments.
Effect of canopy size and shape on the tuber yield of sixteen potato genotypes
Authors: LYNCH D R , KOZUB G C 
Published: February 2008

SummaryAn experiment was conducted to evaluate the utility of visual assessment of canopy characteristics in the selection of high‐yielding clones for the southern Canadian Prairies. Over a 3‐yr period the yield development characteristics of 16 genotypes, selected to represent a range of canopy types, both in size and shape, were studied by destructive sampling at five stages during the growing season. While the response over harvest dates was not consistent for the canopy size or shape groups for most yield variables, it was demonstrated that under the short season growing conditions in southern Alberta, canopies intermediate in size and degree of upright growth habit appear to be most efficient in terms of maximising tuber bulking rates. It was concluded that for the southern Canadian Prairies, selection of genotypes with these types of canopy structure is consistent with the objective of developing early‐maturing cvs with high tuber yield.
Development of a low input system for growing wheat (Triticum vulgare) in a permanent understorey of white clover (Trifolium repens)
Authors: JONES LEWIS , CLEMENTS R O 
Published: February 2008

SummaryIn three field experiments carried out during 1989‐91, a permanent sward of pure white clover (Trifolium repens) was established to provide a source of N for winter or spring wheat crops (Triticum vulgare) directly drilled into the legume. Spring‐sown wheat failed to compete with the clover, but wheat sown in the autumn established successfully. N fertiliser was applied to all three experiments at rates of 0, 50 and 100 kg N ha“1 measurements of grain and whole‐crop silage yields were made. Yields were low for all treatments, probably because of the dry conditions prevailing and the low soil N status of the site used. Yield responses to fertiliser were significant, despite the contribution to plant nutrition that the clover was intended to make. A key feature of the work was that the clover survived successive cereal crops and could be grazed and used as an understorey for later crops. Further, response to fertiliser N diminished with a successive crop implying a build‐up of available soil N, which measurements confirmed had occurred. Use of the system obviated the need to use pesticides, although reasons for the lack of pest damage were not clear.
The origin of variation in seed density in celery (Apium graveolens L.)
Authors: TOORN P VAN DER , KARSSEN C M 
Published: February 2008

SummarySeeds were harvested separately from the sequentially formed umbels to obtain information about the origin of variation in seed density in celery. The study involved seeds from the lowest order (primary) to the highest order (quarternary) umbels from the cvs Mars, Monarch, Selfira and Tall Utah. With increasing umbel order the percentage germination decreased and the mean germination time increased. Seed density increased with increasing umbel order, but was more highly correlated with the length of the seed ripening period which differed for each umbel order due to simultaneous harvesting. The decrease in seed density during seed development was correlated with an increase in air volume in the seeds. It is concluded that the variation in seed density in celery seed lots originated from differences in seed maturity.
The influence of temperature on light enhanced glycoalkaloid synthesis in potato
Authors: PERCIVAL G C , HARRISON J A C , DIXON G R 
Published: February 2008

SummaryThe influence of temperature on total glycoalkaloid (TGA) synthesis in tubers exposed to light (250 jumol m“2 s”2 PAR, Photosynthetically Active Radiation) or dark environments for 96 h was examined in three potato cultivars. Following 96 h light or dark the tubers were stored without light at 5°C or 24°C and TGA concentrations monitored over the subsequent 30 and 90 days. Exposure to light and cultivar were found to be major factors influencing TGA concentrations; temperature had no significant effect. TGA content in illuminated tubers of cvs ‘Pentland Hawk’ and ‘Kerrs Pink’ were significantly higher (P < 0.01) compared with tubers placed in the dark. TGA concentrations in cv. ‘Desiree’ increased significantly only following exposure to light at low temperatures (P < 0.05).Removal of tubers from storage at 5°C and immediate illumination at 24°C altered the ratio of glycoalkaloids in cvs ‘Pentland Hawk’ and ‘Kerrs Pink’. Regardless of cultivar and storage temperature TGA concentrations were higher at the end of the storage period compared with initial TGA concentrations. During storage TGA concentrations fluctuated widely and gradual accumulation of glycoalkaloids with time was rarely demonstrated except in cv. ‘Desiree’. Tubers stored at 24°C accumulated higher TGA concentrations than those stored at 5°C in cv. ‘Kerrs Pink’ but not in cvs ‘Pentland Hawk’ and ‘Desiree’. Tubers of cv. ‘Kerrs Pink’ exposed to light prior to storage accumulated glycoalkaloids more rapidly than unexposed tubers during storage at 24°C and occasionally at 5°C. Light enhanced glycoalkaloids are not degraded over time.
Transmission of the mycoparasite Coniothyrium minitans by collembolan Folsomia Candida (Collembola: Entomobryidae) and glasshouse sciarid Bradysia sp. (Diptera: Sciaridae)
Authors: WHIPPS J M , BUDGE S P 
Published: February 2008

Summary Folsomia Candida was maintained on potato dextrose agar (PDA) plates precolonised by the mycoparasite Coniothyrium minitans for 3 yr but the sciarid Bradysia sp. survived for a maximum of only three generations. Collembolans and sciarid larvae from these cultures were able to transmit C. minitans to uninoculated PDA plates through the survival of spores in faecal pellets. Adult and larval sciarids also transmitted C. minitans from PDA culture to uninoculated PDA plates by contamination on the cuticle. In soil and sand both sciarids and collembolans were able to transmit C. minitans from C. m/m'tans‐inoculated to uninoculated sclerotia of Sclerotinia sclerotiorum. Inoculation of sclerotia with C. minitans enabled greater populations of larger collembolans to develop. In the glasshouse where C. minitans had been applied to the soil, one adult sciarid and four collembolans out of 70 and 101 insects collected respectively yielded C. minitans on placement onto PDA + Aureomycin.
The effectivity of Tilletiopsis albescens in biocontrol of powdery mildew
Authors: KNUDSEN INGE M B , SKOU J P 
Published: February 2008

Summary Tilletiopsis albescens grows well on powdery mildew fungi inoculated on barley or cucumber leaves and causes collapse of the colonies. Application of ballistospores or cut mycelium was equally effective for biocontrol, and the effectiveness tended to increase exponentially with the concentration of germinating units (conidia and cut mycelium) applied. Seventy percent relative humidity or more is required for effective biocontrol. Two applications of T. albescens in the period from 3 days before to 3 days after inoculation with powdery mildew were more effective than one. Applications before inoculation or 7 days after inoculation with powdery mildew had little effect. T. albescens followed the powdery mildew as it was disseminated to uninoculated leaves, but this did not result in an effective biocontrol. The potential for using T. albescens for biocontrol of powdery mildews is discussed.
Flower and nectar attributes of pepper (Capsicum annuum L.) plants in relation to their attractiveness to honeybees (Apis mellifera L.)
Authors: RABINOWITCH H D , FAHN A , MEIR TAL , LENSKY Y 
Published: February 2008

SummaryFlower morphology, nectary structure, nectar traits and rates of honeybee foraging on pepper plants were studied. The nectary appears as swellings on the basal part of the ovary. The nectariferous cells are smaller and denser than the neighbouring parenchyma. Stomata are present in the nectary epidermis, but do not appear on the other parts of the ovary epidermis. Seven pepper breeding lines were grown near a bee yard in Rehovot. Five to six fold differences in nectar volume were found between the extreme genotypes. Nectar volumes were higher during noon and afternoon hours, as compared with morning hours. High correlation coefficients between nectar volume and sugar concentration were found. These were significant for the four high nectar yielding genotypes, ranging between r = 0.65 to r = 0.94. Male‐fertile flowers produced more nectar and higher sugar concentration than sterile ones. Skewed distribution was observed in nectar volume of F2 populations, but relatively low heritability values were calculated.Pepper nectar contains fructose and glucose only. The former occupies 52–82 % of the total sugar content. Pepper genotypes varied in frequency of honeybee visits and significant correlation between sugar quantity and number of honeybee visits per flower was evident. Fertile pepper flowers are not very attractive to honeybees and male‐sterile flowers are even less so. The considerable variation in nectar characteristics can be exploited to increase attractiveness to honeybees, thus facilitating bee pollination in commercial production of F1hybrid seeds and improve fruit quality.
Fungicidal control of damping‐off and seedling root rot in Brassica species caused by Rhizoctonia solani in the growth chamber*
Authors: KATARIA H R , VERMA P R , RAKOW G 
Published: February 2008

SummaryEight fungicides (benodanil, carboxin, cyproconazole, fenpropimorph, fur‐mecyclox, iprodione, pencycuron and tolclofos‐methyl) were evaluated, under growth chamber conditions, as seed treatments against pre‐emergence damping‐off and post‐emergence seedling root rot in six Brassica species. Five cultivars of B. rapa, four cultivars of B. juncea, four cultivars of B. napus and one cultivar/ strain from each of B. carinata, B. nigra and B. oleracea were grown in soilless mix infested with an isolate of Rhizoctonia solani AG‐2‐1. B. nigra and B. juncea were considerably less susceptible to R. solani than the four other species. Cyproconazole at 0.05‐0.1 g a.i./kg seed and the other fungicides at 2–4 g a.i./ kg seed provided almost complete control of pre‐emergence damping‐off in most Brassica species and their cultivars. Their efficacy varied against the post‐emergence seedling root rot. Furmecyclox, iprodione, tolclofos‐methyl and pencycuron consistently gave good control of seedling root rot in all Brassica species and their cultivars. Benodanil and fenpropimorph provided moderate control, and carboxin and cyproconazole gave poor control against root rot. Efficacy of carboxin, cyproconazole, benodanil and fenopropimorph against seedling root rot varied significantly (P ≤ 0.05) among cultivars within a Brassica species.
Fungi and Gram‐negative bacteria as soilborne minor pathogens of goat's rue (Galega orientalis Lam.)
Authors: VALKONEN JARI P T , von HEIROTH WIPATORN , SAVELA MERVI‐LEENA 
Published: February 2008

SummaryFungi and Gram‐negative bacteria were isolated from inside the roots of field‐grown goat's rue (Galega orientalis). Fungi were isolated from three plants out of a total of 45 tested. Two multinuclear Rhizoctonia solani isolates were identified to the anastomosis group 5 (R. solani AG‐5‐Gal) using pairings with known AG test cultures. One fungal isolate was identified to Phoma chrysanthemicola. Gram‐negative bacteria were isolated from three plants out of 25 tested. They were identified using classical methods, the BIOLOG identification system based on the utilisation of 95 different carbon sources, and the MIDI system for the analysis of whole cell fatty acids. The two latter systems were computer‐associated and utilised an extensive reference library of isolates. One bacterial isolate was identified as Enterobacter agglomerans and two isolates as Pseudomonas marginalis. R. solani AG‐5‐Gal reduced the emergence of Lupinus luteus, L. polyphyllus and french bean (Phaseolus vulgaris) and the growth of broad bean (Viciafaba), L. luteus and french bean, but did not cause obvious damage in goat's rue and pea (Pisum sativum). However, R. solani AG‐5‐Gal was re‐isolated from the roots of all the test plant species following inoculation. P. chrysanthemicola reduced the emergence of L. polyphyllus and the growth of goat's rue, french bean and broad bean, and it was re‐isolated from all of the test plant species (except for french bean) following inoculation.All the bacteria reduced the emergence of french bean, but not that of goat's rue and pea, when applied to the soil. When the roots were dipped into bacterial suspension, all the bacteria damaged french bean and L. polyphyllus. Additionally, P. marginalis JV3 damaged goat's rue and red clover. The pathogenicity of the fungi and bacteria were not changed when they were double‐inoculated in pairs, except for R. solani AG‐5‐Gal and P. marginalis JV2 which reduced the emergence of goat's rue when inoculated together but not when inoculated separately.
The peel of plantain and cooking banana fruits
Authors: BURDON J N , MOORE K G , WAINWRIGHT H 
Published: February 2008

SummaryThe peel of the plantain and cooking banana fruit protects the edible pulp from the surrounding environment. The peel of those cultivars examined contained 85–90% water and between 28 and 60 mg dry weight cm‐2 surface area. The ratio of fruit pulp to peel fresh weights differed between cultivars (1.18‐2.28). The surface area of the fruit can be determined from the fresh weight using regression equations for individual cultivars or for all cultivars combined. The stomatal density was generally higher at the fruit tips than at the mid region. Significant differences in stomatal length and density were identified between cultivars although no trends existed between plantains and cooking bananas. There was little difference in the quantity of epicuticular wax on plantains whereas there were differing amounts on cooking bananas. Differences in wax composition between cultivars and for wax extracted with hot or cold chloroform were identified. Removal of the epicuticular wax with chloroform accelerated the rate of weight loss. The use of hot chloroform increased both the amount of wax removed and also the rate of weight loss. The effect of removing the epicuticular wax on water loss is discussed and illustrated with scanning electron micrographs.
Genetic variation in populations of the terrestrial planarian Artioposthia triangulata (Dendy), and evidence for passive dispersal in Northern Ireland
Authors: STEWART VALERIE I , BLACKSHAW R P 
Published: February 2008

SummaryGenetic variation in 12 populations of the terrestrial planarian Artioposthia triangulata from Northern Ireland and one in the Republic of Ireland were assessed using starch‐gel electrophoresis. Seven enzymes ‐ adenylate kinase, aspartate aminotransferase, enolase, malate dehydrogenase, phosphoglucose isomerase, phosphomannose isomerase and superoxide dismutase ‐ provided consistent, resolved stains. Coefficients of genetic identity were similar for all comparisons suggesting that the populations did not belong to distinct taxa. There was no relationship between genetic distance and geographic distance for populations, thus confirming the role of passive dispersal in the spread of A. triangulata. Average percentage polymorphic loci and mean heterozygosities were higher in the east of the Province (41.4% and 0.240), than the west (37.5% and 0.185) suggesting that the planarian had spread westwards after an initial colonisation in the east.