Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 29

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  codling moth
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
Sex ratio, weight, fecundity, fertility and longevity of codling moth, Cydia pomonella (L.) wild adults from wild populations of Southern part of Syria were examined. In addition, percentage of larvae entering diapause from each generation was investigated and the relationship between female weight and fecundity was examined. The results showed that sex ratio was about 1: 1 (males to females), adult weight ranged, on average, from 14.4 to 25.7 mg for spring generation males and females respectively and from 19.5 to 32.6 mg for summer generation males and females in the same order. Fecundity of the spring generation moths was close to 85 eggs/female; this number increased by about 30% for summer generation females and a strong relationship was found between female weight and fecundity. Adult fertility, for both generations (spring and summer), exceeded 90%, longevity ranged from about 10 days for spring generation adults to about 9 days for summer generation moths and males lived little longer than females. These results may serve as a reference in quality control measures for codling moth mass rearing in Syria.
The trials conducted with selected chemical and biological insecticides in 1998-2000 showed the highest effectiveness of Karate Zeon 100 CS (lambda-cyhalotrine) in European corn borer (ECB) larvae control in sweet corn. The efficacy of biological insecticides containing Bacillus thuringiensis ssp. kurstaki: Biobit 3.2 WP and Lepinox WDG was very variable between the years. Reasons for insufficient efficacy of these products are discussed. The most appropriate time for the application of a chemical insecticide against ECB larvae are plant developmental stages since the beginning of pollen shedding to full blooming (63–67 BBCH scale). The efficacy of treatment was the highest at that time.
The present studies were conducted in 1999-2001 in three apple orchards differing from each other by the system of cultivation, the type of agricultural treatments and chemical control of pests. Their purpose was to monitor codling moth (Cydia pomonella L.) in different types of apple orchards using pheromone traps, finding out the relation between the occurrence of moths and the sum of effective temperatures as well as determining the number of wintering caterpillars of this species with the use of bands of corrugated paper. The analysis of male flight of codling moth on the basis of pheromone traps makes it possible to state the occurrence of two generations in each studied year. The maximum population of the first generation was observed in the second or third ten days of June, while that of the second generation in the first ten days of August. The moths flight began when the sum of effective temperatures was 109.2-145.2°C, and the mean diurnal temperature was 12.3-17.2°C.
In preliminary experiments, we show that extracts from Artemisia absinthium, and Artemisia arborescens x absinthium “Powis Castle” have deterrent properties against neonate larvae of codling moth, Cydia pomonella. By partitioning crude extracts and comparative High Performance Thin Layer Chromatography we suggest candidate feeding deterrents for further analysis.
The codling moth (CM), Cydia pomonella (L.), causes heavy damage in Bulgarian apple orchards. Conventionally treated orchards, were monitored in this study. In spite of numerous chemical treatments, these orchards showed increasing flight densities of CM moths, growing populations of hibernating larvae and rising fruit damage rates. Thus, the control of CM by conventional spraying programmes became ineffective, apparently due to the development of resistance to insecticides. Products based on the Cydia pomonella granulosis virus (CpGV), such as Madex®, may provide alternative control tools that can be applied with other approaches, for a sustainable control strategy. The trials were carried out in Central-South and South-East Bulgaria, in 2006-2010. Four treatments of Madex® against the first generation, and six treatments against the second generation kept the fruit damage and population density of CM at a low level. Based on the obtained results, different control strategies have been suggested, depending on the initial CM pressure in a particular orchard. Madex® may be a promising alternative to traditional programmes of CM control. Its dose, however, should be adjusted to the initial CM population density. Also, at a high or moderate CM population density Madex® applications should be combined with MD to avoid resistance of CM to granulovirus. At the peak of CM hatching, additional chemical treatments may be sometimes necessary. Such treatments include using insecticides which are still effective against CM.
In the years 2007–2009, trials on control of codling moth (CM), Cydia pomonella (L.), were carried out in apple orchards of South-East Bulgaria, where the pressure of the pest was very high. Mating disruption with Isomate C plus dispensers was applied in combination with sprays of the virus product Madex®. With a single installation of Isomate C plus dispensers per season + 4 treatments of Madex® at 100 ml per ha against the first and 6 treatments against the second generation, fruit damage at harvest and population density of codling moth were kept at a low level. At the same time fruit damage and population density of the pest, as estimated by the hibernating CM larvae population, was very high in the conventionally treated orchard serving as a reference. Using Isomate C plus dispensers and the baculovirus product Madex® may be a promising alternative to traditional programmes trying to control high initial infestation of codling moth. For Bulgaria, the combined tested strategies of mating disruption and virus control are suggested for control of codling moth in the orchards with CM population density of more than 3 larvae per tree or more than 5% fruit damage in the previous year.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.