P. Benedek

22984441300

Publications - 5

Development and parasitism of the horse-chestnut leafminer, Cameraria ohridella, in different leaf types and canopy levels

P. Benedek B. Horváth

Publication Name: Acta Phytopathologica Et Entomologica Hungarica

Publication Date: 2009-12-01

Volume: 44

Issue: 2

Page Range: 277-293

Description:

Authors provide a 6-year study about aspects of development of Cameraria ohridella and its parasitoids in different leaf types of horse-chestnut trees. Investigations were carried out near Hédervár, North-West Hungary between 1999 and 2004.It was ascertained that in large leaves at low foliage levels as well as in large leaves exposed to direct sunlight developed more moths than in other leaf types of equal quantity (i.e. equal number of leaflets). On the other hand, there were not considerable differences between shaded and sun-exposed leaves in this regard if their quantity is measured in grams. Moreover, comparing the numbers of hatched moths per unit leaf weight, the values for minute leaves were the highest. The differences were explained on the basis of diverse microclimatic conditions in the mines, height preference of the moth or variations in dry weights per unit leaf area.Parasitism of Cameraria ohridella showed significant yearly differences between canopy levels and a tendency of changes during the years. Parasitism was higher in shaded than in sun-exposed leaves. Lowest values were found in minute leaves among all leaf types investigated what was explained with a presumed foraging behaviour of the parasitoids.Structure and species constitution of the parasitoid community and its changes in time are discussed in different leaf types. Temporal changes of several characteristics found in different leaf types refer to an adaptation process of the horse-chestnut leafminer. © 2009 Akadémiai Kiadó.

Open Access: Yes

DOI: 10.1556/APhyt.44.2009.2.6

Parasitism of different life stages and phenology of the horse-chestnut leafminer ( Cameraria ohridella ) and its parasitoids

P. Benedek B. Horváth

Publication Name: Acta Phytopathologica Et Entomologica Hungarica

Publication Date: 2009-12-01

Volume: 44

Issue: 2

Page Range: 295-313

Description:

The horse-chestnut leafminer is a new pest which was established in North-West Hungary ca. 10 years prior to these investigations. Due to the very limited time, there are relatively few studies on the parasitoid community of the moth and its connection with the leafminer host. Authors used twig-isolators to find out which larval/pupal instars are mostly parasitized and by which chalcidoid species. They also made an attempt to calculate density curves of different developmental stages of the moth and to compare them with flight curves of the parasitoids. Experiences indicated that 4-week-old larval (pupal) instars were parasitized to the highest degree. The most frequent parasitoids were Pediobius saulius and Pnigalio agraules . Statements about a poor synchronization between moth and parasitoids were confirmed but possibility of a shift in swarming times on location was suggested. Different methods to calculate rate of parasitism were compared and evaluated. © 2009 Akadémiai Kiadó.

Open Access: Yes

DOI: 10.1556/APhyt.44.2009.2.7

The effect of reduced bee pollination period to the fruit set of apricots

I. Skóla L. Szalay P. Benedek Z. Erdos J. Nyéki

Publication Name: Acta Horticulturae

Publication Date: 2006-01-01

Volume: 701 II

Issue: Unknown

Page Range: 723-726

Description:

The duration of effective bee pollination period was limited by caging flowering branches for shorter or longer time. In the case of self-fertile apricots even a partial limitation of the effective duration of bee pollination period significantly reduced the fruit set and the yield. This is because pollen dehiscence of anthers and the receptive period of stigmas do not overlap in time within the individual flowers. Accordingly, additional bee pollination (moving bee colonies to the orchards at blooming period) is needed to get a profitable yield when bee visitation of plantations is not abundant enough for some reasons.

Open Access: Yes

DOI: 10.17660/ActaHortic.2006.701.129

Nectar production, honeybee visitation and fruit set of peach flowers

L. Szalay P. Benedek J. Nyéki Z. Szabó

Publication Name: Acta Horticulturae

Publication Date: 2002-01-01

Volume: 592

Issue: Unknown

Page Range: 537-541

Description:

Peach varieties grown in Hungary are self-fertile and set sufficient fruit under favourable weather conditions by natural self-pollination. The literature as well as our observations, suggests that bee pollination enhances fruit set even in selffertile varieties. The nectar production (0.30-9.09 mg/flower) and its dry matter content (12.5-58.1 %) varied widely by variety and sampling date. In relation to other stone fruit species peach was relatively low in nectar production (2.2 mg/flower) as well as in dry matter content (30.5 %). In spite of the low nectar, honeybees frequently visited production peach flowers. The reason for that is due to the early blooming time of peach, when honeybees have less available resources. Under favourable weather conditions (sunshine, calm warm weather) 20 % of the flowers on a branch were visited within a 10-minute period. Thus the same flower received several visits during one day. About half the bees visiting peach flowers were nectar gatherers. Another 27 % were pollen collectors and the remaining 23 % displayed mixed behaviour of collecting both pollen and nectar. The limitation of honeybee visits impaired the fruit set less in peaches than in other stone fruit species. Nevertheless, fruit set was markedly different between open flowers and isolated (bagged) flowers.

Open Access: Yes

DOI: 10.17660/ActaHortic.2002.592.72

New results on the bee pollination of quince (Cydonia oblonga Mill.)

P. Benedek T. Szabó J. Nyéki

Publication Name: Acta Horticulturae

Publication Date: 2001-01-01

Volume: 561

Issue: Unknown

Page Range: 243-248

Description:

The research was conducted on 6 cultivars over three consecutive years. Nectar production of quince was found to be small compared to other temperate zone fruit tree species, since quince flowers contained 1.07 - 0.06 mg of nectar on average. Sugar concentration ranged between 21-27 % on average in different years with a range between 9-47.5 %. There was a significant negative correlation between the amount of nectar and its sugar concentration, but no definite difference was established between the ne ctar production of quince cultivars. In spite of this, bee visitation was highly intense about 5.5 bee visits were counted on average at 50 open quince flowers in 10 minutes and about 9.7 flowers out of 50 were visited. This equals about 7 bee visits per flower per day in good weather. Some cultivars tended to be more and less visited by honeybees. Most honeybees tended to collect pollen (51.6 % in average for the 3 years) and usually fewer gathered only nectar (19.9 %), while the rest had a mixed foraging behaviour gathering both (28.5 %). There were slight differences in the foraging behaviour of honeybees on some cultivars, but these differences were not always consequent in consecutive years. Quince is highly sensitive to partial and/or complete limitation of the insect (bee) pollination period. Complete limitation of insect pollination resulted in no yield and partial limitation of the insect pollination period depressed the final set and yield by at least 60-70 % or more. Significant correlation was established between the intensity of honeybee visitation and the consequent yield of quince. As much as 4-5 or 8-10 honeybee visits are needed per day on one flower to achieve the required optimal fruit set that has been declared in the literature to be 20-25 % for quince.

Open Access: Yes

DOI: 10.17660/ActaHortic.2001.561.35