ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science Ltd
    Plant pathology 49 (2000), S. 0 
    ISSN: 1365-3059
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: The effects of temperature on the length of the incubation and latent periods of hawthorn powdery mildew, caused by Podosphaera clandestina, were studied. At constant temperatures over the range 10–28°C, the incubation period ranged from 5 to 14 days and the latent period from 5 to 16 days; no visible colonies had developed at 30°C after 15 days. The relationships between temperature and the rates of fungus development within the incubation and latent periods were well described by a nonlinear model. The resulting curves were asymmetrically bell-shaped with an optimum temperature of approximately 23°C. The lengths of the incubation and latent periods under fluctuating temperatures were also determined, and were used to evaluate the models developed from constant temperature experiments for their accuracy of prediction. The incubation and latent periods under fluctuating temperature regimes were predicted using a rate-summation scheme with a time step of 24 min, by integrating the respective incubation and latent rate functions obtained under constant temperatures. The predicted incubation or latent periods agreed well with the observed values. Under constant temperature the interval between the times when symptoms and sporulation on the same leaflet were first observed was very short, on average 〈1 day, and was not significantly correlated with temperature. However, this interval was negatively correlated with mean temperature under fluctuating regimes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science Ltd
    Plant pathology 50 (2001), S. 0 
    ISSN: 1365-3059
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Spatio-temporal development of brown rot (Monilinia fructigena) on apple and pear was monitored in an apple (cv. Cox) orchard and a pear orchard of several cultivars over several years. Disease on individual trees was recorded weekly from July to harvest, individual fruits with brown rot were tagged but not removed and rot-origin identified. On apple cv. Cox and pear (cvs Conference and Comice), all primary rot arose from infection via wounds caused by insects, birds and growth cracks. Birds were the most important wounding agents on pear in the field. Secondary (fruit-to-fruit contact) rot was considerably less than primary rot, especially for pear. Incidence of disease (percentage of fruits with brown rot) increased gradually from late July up to harvest; the final disease incidence varied with seasons and cultivars, ranging from 1 to 11%. For pear, Comice had greater incidence than Conference. Significant aggregation of diseased fruits among trees was detected for assessment dates when the overall incidence of disease was greater than 0·5%. On Cox and Conference, significant correlation of disease incidence between adjacent trees or trees separated by one or more trees (i.e. spatial lag measured as units of distance between adjacent trees) was detected, but there was no clear relationship between the correlation, the distance or time. For Comice, there was consistent and significant positive correlation of brown rot incidence over 3 years. It is speculated that behavioural characteristics of wounding agents may have played an important role in influencing the spatio-temporal dynamics of brown rot on apple and pear.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1365-3059
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Experiments were conducted to investigate the effects of temperature and relative humidity (RH) on the in vitro germination and viability of conidia of the apple brown rot fungus (Monilinia fructigena), and on colonization and sporulation on detached fruits by M. fructigena. Conidia only germinated under near-saturation humidity (≥ 97% RH) and the rate of germination initially increased with temperature to a maximum at ≈ 23–25°C and then decreased. Conidia germinated rapidly – more than 70% of viable conidia had germinated within 2 h at 20 and 25°C. The rate of colonization on detached fruits increased log-linearly with increasing temperature. Sporulation on detached fruits was not observed at 5 or 25°C; sporulation appeared to be unaffected by either temperature (10–20°C) or RH (45–98%) once infection was established. Detached conidia remained viable for a long period of time, up to 20 days, the longest assessment time in this study, depending on storage temperature (10 or 20°C) and RH (45 or 85%). Temperature appeared to be more important than RH in affecting conidial viability. Low temperature and high RH resulted in reduced loss of conidial viability. Storage at 10°C and 85% RH for up to 20 days appeared not to affect conidial viability. These results indicate that environmental conditions during the main UK growing seasons are unlikely to be limiting factors for the development of brown rot on apple.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2004-06-01
    Description: Inclusion in the diet of concentrations of vitamin E and selenium (Se) above requirement is associated with variable improvements in animal performance and immune function. At the cellular and molecular level, research in the last decade has produced a clearer understanding of the mechanisms underlying the multiple functions of vitamin E and Se and it is apparent that these functions extend beyond antioxidant protection. This paper reviews recent research relating to the functionality of vitamin E and Se in relation to the ewe and her lambs and attempts to relate this understanding to the whole animal level. Important aspects of this improved understanding are descriptions of three groups of seleno-proteins and the appreciation that there is a hierarchy in both the distribution of selenium between tissues and in the synthesis of different enzymes within tissues. In addition, there is diversity in the effects of vitamin E and Se derivatives on immune cell function. Given this heterogeneity in function it is not surprising that published responses for the production and health of ewes and lambs to supplementary vitamin E and selenium are variable and not always positive. Coupled with information on factors influencing variability in supply of vitamin E and Se from fresh and conserved forages and concentrate supplements, this review highlights the need for greater awareness of the importance of adequate supplementation of ewe and lamb diets with vitamin E and Se.
    Print ISSN: 0021-8596
    Electronic ISSN: 1469-5146
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...