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• The effect of spring frosts on the nectar production and the bee visitation of fruit trees

  86-89.

  P. Benedek

  J. Nyéki

  I. Amtmann

  F. Bakcsa

  J. Iváncsics

  Z. Erdős

  I. Skola

  Views:

  228

  Fruit tree species suffered very strong spring frosts in 1997 in Hungary. This caused partial or total damages at buds and flowers depending on site and time of blooming. It was demonstrated at a number of experiments that frost and cold weather also strongly affected the nectar production of surviving flowers. No or very little amount of nectar was measured in flowers first of all of early blooming fruit tree species (apricot) but also of pear and apple in some places. In spite of this fact intensive honeybee visitation was detected in the flowers of fruit trees that suffered partial frost damage only at those sites where honeybee colonies were placed in or at the experimental plantations and the lack of sufficient amount of nectar did not affected bee behaviour seriously on fruit flowers. This means that bad nectar production failed to affect bee visitation of fruit trees definitely. The reason for this was the fact that not only fruit trees but another early bee plants (wild plants, too) suffered frost damage. Accordingly, in lack of forage bees intensively searched for food at blooming fruit trees with some living flowers. Consequently, there was an acceptable yield at those plantations where bud and flower damage was not complete. Accordingly, intensive bee visitation (that is moving additional bee colonies to overpopulate fruit orchards with honeybees) can be an effective tool to decrease or eliminate the detrimental effect of spring frost on the yield of fruit trees where bud or fruit damage is not too high.

   

• Content of mineral- and sulphur compounds in Hungarian and French garlic varieties

  61-65.

  J. Iváncsics

  Cs. Gombkötő

  N. Gombkötő

  Á. Máthé

  Views:

  255

  In our days about 2 million tons of garlic are grown in the world. Garlic was used as medicine already in ancient Egypt. It contains approx 33 sulfur compounds, several enzymes, 17 amino acids and minerals. We determined the content of diallyl sulfone, boron, calcium, copper, iron, potassium, magnesium, natrium, phosphorus and zinc in fi ve garlic varieties (3 French, 2 Hungarian). We searched if there were signiffi cant differences between the varieties.

• Selection of the chance seedlings of `Mézes körte' (Pyrus communis L.) from the gene bank of Keszthely

  21-27.

  J. Varga

  J. Iváncsics

  G. Kocsisné Molnár

  J. Nyéki

  Views:

  259

  We have concluded the selection tests of the `Mézes körte' seedlings planted in the spring of 2006, with special emphasis on the cotyledonary, foliage leaf and the height of plant. Out of the 75 seeds planted in rows, there were 40-45 pieces growing out, so during the first cotyledonary test we had to calculate with almost 40% decay. On 12th April 2006, we recorded some of the important characteristics of the seedlings in their cotyledonary stage which characteristics were important from the point of view of selection (cotyledonary form, cotyledonary length, cotyledonary thickness, cotyledonary colour, cotyledonary petiole length, cotyledonary petiole thickness, cotyledonary petiole colour). The above morphological characteristics are shown in Table No. 1-6. We have also tested the seedling in foliage leaf state, paying special attention on the development stage of the plants (colour of foliage leaf , height of plant). We have completed statistical calculations of the two above mentioned characteristics. The result of that is summarised in Table No. 8-9. The variation coefficient show smaller value in the case of the foliage leaf number (15-32%), while the wider range of spread of the data referring to the height of the plant is shown by the 33-61% CV values. On charts No 4-9. we present the relationship between the height of the plant and the number of foliage leaf, as well as the differences between the two graphs. Based on the above charts and graphs it can be defined that the 40% destruction of the developing seedlings during the period till the next measurement reached 70-80% level. In spite of this however some seedlings showed strong and balanced growth (A₄₄, B₄₂, C₂₅, D₁₆, E₅, E₃₉, F₃₈), the further testing and selection of those is to be completed in the future.

• Tree growth and inner characteristics of fruits in pear cultivars

  29-32.

  J. Iváncsics

  Z. Vadas

  G. Jekkel

  Views:

  134

   

  Summary The aim of study was to investigate growth (crown growth and trunk diameter) and fruit characteristics [dry matter content (%), pectin (%), total acid (%) contents] of 10 pear cultivars ('Móri császár', 'Nyári Kálmán', 'Mogyoródi óriás', 'Fehérvári körte', 'Szegfa körte', 'Piroska', 'Mézes körte'). The crown development of the cv. 'Fehérvári körte' can be regarded as outstanding among the examined cultivars. The growth of the cv. 'Mogyoródi óriás' was low, this cultivar showed the poorest growth vigour. The width of the crown in several cultivars developed at a similar rate as the height of the crown. Outstanding values were shown by cvs. 'Fehervári körte' and 'Móri császár'. The development of trunk diameter was the highest for cvs. 'Piroska' and 'Hóka', and large growth of trunk diameter can be seen on cv. 'Fehervári körte'. Cvs. 'Mogyoródi óriás' and 'Mezes körte'showed weak growth. Outstanding dry matter content of fruits was measured on cvs. 'Fehervári körte' and 'Mézes körte'. The total acid content of fruits of cvs. 'Mézes körte' and 'Fehérvári körte'' was significantly different from the total acid content of cv. 'Mogyoródi óriás'. Pectin content was low in fruits of cvs. 'Mogyoródi óriás' and 'Fehérvári körte', while cv. 'Mézes körte' contained significantly more pectin. Vitamin C content we found was rather high in cvs. 'Mézes körte' and 'Fehérvári körte'.

   

• Self fertility of pear varieties conditioned by natural self pollination (autogamy)

  110-113.

  J. Nyéki

  M. Soltész

  J. Iváncsics

  Views:

  287

  Authors studied the autofertility depending on natural self pollination (autogamy) in 59 pear cultivars during 4 seasons at three locations with different ecological conditions (Helvetia, Kecskemet-Kisfai, Keszthely). The aim of the experiments was to determine the autogamous tendencies of varieties hitherto unexplored in the Hungarien gene bank, or to check data found in the literature. A total of 42616 isolated pear flowers produced 1.2% fruits with at least one viable seed in each. The 59 varieties observed did not set fruit by autogamy on either of the three sites during the four years of the study. The triploid (3n=51) varieties were entirely self-sterile. According to the highest autogamous fruit set, during the experimental period, the varieties have been assigned to four groups: (1) Entirely auto-incompatible (0% fruit set), (2) auto-incompatible (0.1 to 0.9%), slightly self fertile (1.1 to 5%) and (4) self fertile (5.1 to 10%). According to the number of viable seeds per fruit resulting from autogamy, the varieties are assigned to three groups as (1) low seed content (less than 3 seeds per fruit), medium (3.1 to 5) and (3) high (more than 5 seeds). Thus, the assessment of the number of seeds per fruit resulting from autogamy is indispensable as a proof of the absence of parthenocarpy.