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Grey mould, caused by Botrytis cinerea and other Botrytis spp., is a major cause of fruit rot in strawberries and other fruit crops worldwide. Repeated fungicide applications are essential in order to secure harvests. However, resistance to all currently registered single-site fungicides is widespread. The rising importance of strains with multiple resistance to most or all fungicides is of particular concern. These strains may be introduced into fields via contaminated nursery plants and/or by immigration from adjacent plots. On the basis of research conducted in northern German and Danish strawberry production, a concept to manage fungicide resistance under northern European conditions has been developed and put into regional strawberry production practice. This principally includes the testing of nursery plants for fungicide-resistant Botrytis strains prior to planting; the restricted and specific use of fungicides at flowering in the production fields, taking account of the resistance spectrum within the local Botrytis population; and crop sanitation measures such as the removal of rotting fruits at the beginning of harvest. Further options such as protected cultivation, reduced fertilisation and biological control are also discussed. The practical implementation of such a strategy in northern Germany and Denmark has been shown to reduce the occurrence of multi-resistant strains to a tolerable steady-state level. [ABSTRACT FROM AUTHOR]

Separate experiments were conducted to evaluate the effect of plant canopy shape and presence of flowers on counting accuracy of container-grown plants. Images were taken at 12 m above the ground. Two species of juniper (Juniperus chinensis L. 'Sea Green' and Juniperus horizontalis Moench 'Plumosa Compacta') were selected to evaluate plant shape and Coral Drift ® rose (Rosa sp. 'Meidrifora') was used to evaluate the presence of flowers on plant count. Counting algorithms were trained using Feature Analyst (FA). Total counting error, false positives and unidentified plants were reported. There was no difference between all variables measured when an algorithm trained with an image displaying regular or irregular plant canopy shape was applied to images displaying both plant canopy shapes even though the canopy shape of 'Sea Green' is less compact than 'Plumosa Compacta'. There was a significant difference in all variables measured between images of flowering and non-flowering plants when non-flowering 'samples' were used the train the counting algorithm in FA; total counting errors and unidentified plants was greater for flowering plants. In this specific case, applying an algorithm that did not include a training set displaying flowers, resulted in a less accurate count. Algorithms developed using FA appears to be fairly robust under these conditions. [ABSTRACT FROM AUTHOR]

The occurrence of Phaeomoniella chlamydospora was investigated during vine propagation in an Italian nursery, and combined hot water (HWT) and cyproconazole treatments were carried out to limit the spread of the fungus in nursery vines. In the three-year period 2005-2007, cutting and graft samples (scion cv. Sangiovese, rootstock cv. 140Ru in 2005 and 1103P in 2006-2007) were taken during propagation at several infection risk stages, and the occurrence of P. chlamydospora was assessed by nested PCR. In 2005 and 2006, cuttings from esca-symptomatic grapevines (scion cv. Sauvignon blanc, rootstock cv. 140Ru in 2005 and 1103P in 2006) were treated at different stages of the propagation process. In 2007, artificially infected 1103P cuttings were treated with HWT and cyproconazole after being inoculated with P. chlamydospora, and the fungus was detected by isolation on agar medium. The effect of HWT on the growth of 1103P, 779P, Sangiovese and Cabernet franc cuttings was also assessed. Despite extended wood discoloration, P. chlamydospora was scarce in nursery vines during the three-year period. The contamination of planting material may have resulted from already infected mother plants (0.0 to 6.7% of infected cuttings) or may have started during the propagation, particularly after grafting (0.0 to 23.3% of infected grafts). Canes from esca-diseased mother plants were always infected, but the incidence of infection of the cuttings varied widely (about 30% in 2005, from 1.9 to 4.1% in the other years). However, no final conclusions could be drawn about the stage or stages at which the nursery vines mainly became infected, because the infection frequencies detected in the propagation process were too low and irregular. As regards control of P. chlamydospora, HWT of cuttings performed before or after cold storage influenced plant growth, depending on both the cultivar and the growing conditions, but HWT was harmful to callused graftlings. Natural contamination of nursery material in 2005 and 2006 was insufficient to allow the effectiveness of treatments to be assessed. In 2007, HWT and cyproconzole alone did not reduce the percentage of infection in artificially inoculated cuttings. Only cyproconazole immediately followed by HWT significantly reduced the number of infected cuttings, but this procedure did not eradicate the pathogen. [ABSTRACT FROM AUTHOR]

The differential grasshopper, Melanoplus differentialis (Thomas) (Orthoptera: Acrididae), frequently migrates from highway rights-of-way, pastures, and harvested fields to feed in urban/suburban landscapes and retail/wholesale nurseries across the southern and southwestern U.S.A., as these areas dry down during hot dry summers. Nine selected turfgrasses and 15 species of landscape plants were evaluated for their susceptibility or resistance to this grasshopper. Grasshoppers were collected from stands of Johnsongrass, Sorghum halepense , which was used as a standard host for comparison in both experiments. Based on feeding damage, number of grasshopper fecal pellets produced, and their dry weight, Zoysia matrella cv. 'Cavalier' was the least preferred grass followed by Buchloe dactyloides cv. 'Prairie' and Z. japonica cv. 'Meyer'. Festuca arundinacea was significantly the most preferred host and sustained the most feeding damage, followed by Poa pratensis × P. arachniferacv. 'Reveille' and 2 Cynodon spp. cultivars, 'Tifway' and 'Common'. Among the landscape plants, Hibiscus moscheutos cv. 'Flare', Petunia violacea cv. 'VIP', Phlox paniculata cv. 'John Fanick', Tecoma stans cv. 'Gold Star', and Campsis grandiflora were the least damaged or most resistant.Plumbago auriculata cv. 'Hullabaloo', Glandularia hybrid cv. 'Blue Princess', Canna × generalis, Johnsongrass, and Cortaderia selloanacv. 'Pumila' sustained the most damage. Based on the number of fecal pellets produced and their weights, Canna × generalis and Glandularia hybrid cv. 'Blue Princess' were the most preferred landscape plants tested. [ABSTRACT FROM AUTHOR]

Nonindigenous freshwater species cause large ecological and economic impacts in Great Britain. In response the government is in the process of implementing a broad, new nonindigenous species strategy. We assembled a list of all nonindigenous freshwater species that are or were established in Great Britain, their date of first record, and their vector of introduction. This list provides a baseline against which the success of new policies can be assessed. Because the biota of Great Britain has been well recorded, our results provide a highly resolved case study of the vectors and drivers of species transport and establishment. A total of 117 nonindigenous freshwater species are currently established in Great Britain; a further 17 species were once established but are now extirpated. Between 1800 and 2000 the number of established species increased at an accelerating rate, and this increase correlated with the growth in human population and gross domestic product. The construction of large reservoirs in Great Britain occurred over a short period and overlapped high rates of new species establishment, indicating that habitat modification may have been an important driver of establishment. Nonindigenous species now account for 24% of fish, 12% of plant, 54% of amphibian, and 88% of decapod crustacean freshwater species richness in Great Britain. The ornamental trades have been responsible for the greatest percentages of intentionally (73%) and unintentionally (34%) introduced species that have become established. Shipping and aquaculture have also been strong vectors. These vectors should be prioritized for management within the new nonindigenous species strategy. [ABSTRACT FROM AUTHOR]

Investigations were conducted in the greenhouse of the Faculty of Agriculture with the aim of studying the influence of biostimulators on the quality of medicinal, aromatic and herb nursery plants. The nursery plants of basil (Ocimum basilicum L.), lemon balm (Melissa officinalis L.), cone flower (Echinacea angustifolia D.C.), lavender (Lavandula angustifolia Mill.), rosemary (Rosmarinus officinalis L.) i marjoram (Majorana hortensis L.) were grown in polystyrene containers (Speedling system) 76 cm³ in size. The first part of the experiment was focused on the effect of the natural biostimulator Viva (3 ml/1) and Megafol (1.5 ml/1) on the quality of basil, lemon balm and cone flower nursery plants. The second part of the study encompassed the influence of different Viva biostimulator rates (0 - control, 1, 2, 3, 4 ml/1) on the quality of lavender, rosemary and marjoram nursery plants. Viva soil biostimulator and Megafol leaf biostimulators were added during the production of nursery plants at 10-day intervals. Based on the results obtained, a positive effect of natural biostimulator (Viva and Megafol) use was noted in the production of basil, garden balm and cone flower nursery plants. In addition, the use of different Viva biostimulator rates in the production of lavender, rosemary and marjoram nursery plants showed positive influence. The highest Viva biostimulator rate (4 ml/1) showed the most favourable effect on lavender and marjoram nursery plant quality. In case of rosemary nursery plants the rate of 3 ml/1 was the most favourable. [ABSTRACT FROM AUTHOR]

A leach collection unit (LCU) was assembled to capture all leachate draining from a nursery container. An injection molded 2.8-L nursery container was plastic welded into the lid of a 7.6-L black plastic collection bucket so that the bottom 2.5 cm of the nursery container protruded through the lid. The LCU was designed to track total N release from CRFs without confounding effects of plant uptake or N immobilization. Total N released between any two sampling periods is determined by multiplying the N concentration in a leachate subsample × total leachate volume. The LCU were placed in a container nursery area with overhead irrigation. LCU were thoroughly leached before sampling the leach solution. To study the effects of substrate on N leach rates, Osmocote 18.0N-2.6P-9.9K (8 to 9 months 21 °C) was incorporated at 1.8 kg N/m³ using a locally available, bark-based substrate or medium-grade quartz sand. The experiment was conducted at Scotts Research locations in Apopka, Fla., and Marysville, Ohio. Osmocote incorporated into either a bark-based substrate or sand resulted in similar N release profiles. Although substrate did not affect N leach rate, quartz sand was recommended as the substrate in the leach collection system for polymer-coated CRFs. Quartz sand is chemically and biologically inert, does not immobilize nutrients and has low ion exchange capacity compared to bark-based potting substrates. More than 90% of the total nitrogen applied from Osmocote was recovered from leachate and unreleased N in fertilizer granules. This research has demonstrated the leach collection system as a reliable means to quantify nitrogen release rate of a polymercoated CRF under nursery conditions. The LCU, when used with a crop plant, allows nutrient budget and nutrient uptake efficiency to be determined for CRFs. [ABSTRACT FROM AUTHOR]