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  • Preliminary studies on propagating natural mason bee (mixed Osmia cornuta and O. rufa) populations in artificial nesting media at the site for fruit orchard pollination
    95-101.
    Views:
    257

    Preliminary field management studies were made to increase the population density of native early spring Osmia species (O. cornuta, O. rufa) at fruit tree plantations in Hungary. Initial bee activity around artificial nesting media and the population increase during consecutive years were much smaller at large commercial fruit orchards under intense chemical plant protection than in small mixed fruit plantation with moderate or low pesticide usage. Osmias accepted all the four kinds of tested artificial nesting media (reed, bamboo rods, hardwood blocks and light walling blocks with drilled holes). Reed provided the best nesting conditions so it is suggested to be used in the practice. Calculations showed that under favourable conditions more than 50 to 100 thousand incoming flights (arrivals or landings) occurred in a single day around a single bee shelter and this makes enormous number of possible bee visits at fruit tree flowers. For this reason it is strongly recommended to put simple bee shelters filled with artificial nesting media into fruit orchards. Experiences show that the population sizes of Osmias increase during consecutive years without any specific additional maintenance except providing shelters and nesting media.

  • Self pollination in peach
    76-78.
    Views:
    137

    The peach is though considered to be a self fertile fruit species, also some self sterile and male sterile varieties have been registered. The latter type seems to be frequently met in Asian varieties, whereas in the USA and Europe, J. H. Hale and Flaminia are grown. The purpose of the present study was the assessment of fertility relations of peaches and nectarines grown in Hungary. The authors studied, since 1974, more than 100 different peach and nectarine varieties as for fertility relations, especially their autogamous or geitonogamous fruit set on isolated, i.e. bagged flowers at bud stage, then set free after blooming finished. Isolated flowers of some varieties were also self pollinated, artificially. According to the results the varieties have been assigned to four alternative groups. Self sterile varieties in the proper sense have not been found, but partial self sterility (less than 10% fruit set), self fertility (10 to 20% fruit set) and high self fertility (more than 20% fruit set on selfed flovters) was generally met. The majority of the varieties belonged to the last two groups, nevertheless. the rate of fruit set displayed seasonal variation, the maximum was in one case 89.9%. The purposeful self (hand)pollination of the isolated flowers increased fruit set, substantially. Varieties rated as partially self-sterile are J. H. Hale and Fuzador (the former being partially male sterile too). Although in some years and some varieties, fruit set legged below 10% but according to the means the majority of nectarines are assigned to the self fertile category whereas most peach varieties, either for fresh consumption or industrial types, were highly self fertile.

     

  • The expression of the primigenic dominance in the flowering and fruit set of selected apple cultivars on different growth inducing rootstocks
    27-31.
    Views:
    200

    Authors investigated the expression of the primigenic dominance in the flowering and fruit from open and self pollination of four apple cultivars ('Gala Royal', 'Golden Smoothee', Pink Lady' and 'Vista Bella') during two consecutive years in Western Hungary on three different growth inducing rootstocks (M. 9, MM. 106 and seedling). There were not significant differences in the effect of the rootstocks on the flowering order in a flower cluster. Significant difference in the fruit set in open pollination was found among individual flowers in a cluster, mostly between the king bloom and the second flower. The rate of the fruit set from self-pollination was very low without any significant difference among individual flowers in the cluster.

  • Floral biology of tree fruit rootstocks
    153-161.
    Views:
    152

    The modern nursery industry requires seed sources of a high quality and regular quantity year by year. Besides the seed sources of processed cultivars (Bartlett pear, Shipley, Elberta peach) special seed orchards are planted with selected seed trees producing high quality and genetically determined seed (hybrid seed or inbred lines). Seedlings are still the most common commercial source of rootstocks for stone fruits (almond, apricot, peach, plum, prune and walnut). Although clonal rootstocks are spreading, usage of seedlings is still predominant at stone fruits and nuts. For successful seed production and planning of seed orchard the knowledge on floral biology, flower fertility, pollination, blossom time of trees (selected clone or cultivars) used for seed production is essential. In this field very little systematic research was carried out most of the papers were published in the second half of the 20th century. Our mini review gives an overview on the importance of flower fertility in the mating systems applied in seed orchards, and the research results on floral biology of fruit tree rootstocks propagated by seed (Prunus avium, Prunus mahaleb, Prunus armeniaca, Prunus cerasifera, Prunus insititia, Prunus amygdalus, P persica, P amygdalopersica, Pyrus pyraster, Pyrus communis and Pyrus betulifolia) over the last decades.

  • Morphological and phenological properties of sour cherry varieties grown in Hungary and their inter-incompatibility relations
    114-117.
    Views:
    151

    Regular observations and experiments were performed during a 14 year period on 6 sour cherry varieties. The morphological traits of leaves and fruits were compared, and the phenology of blooming as well as of ripening dates served to start an estimation of the possibilities of mutual pollination and the planning of harvest operations. Experiments involved obligate autogamy, artificially controlled allogamy and open pollination in order to reveal self-fertility, self-sterility or inter-incompatibility relations.

    The varietal characters represent, each, different values in the distinction of the items, because of their intra-varietal variability. From that point of view, the most reliable are the data of blooming and ripening time, fruit size and the fertility relations.

    Inter-incompatibility was observed between the group of self-fertile, "Pándy type" varieties (`Újfehértói fürtös’, ‘Debreceni bőtermő’, ‘Kántorjánosi’) on one side and the selection of Pándy 7', a self-sterile variety on the other side. Unilateral incompatibility has been detected within the former group of new, self-fertile varieties, the combinations: (`Újfehértói fürtös’ x ‘Debreceni bőtermő’ as well as `Újfehértói fürtös’ x Kántorjánosi’.

    Our results prove the close kinship between those three new varieties and the original Pándy variety on the base of being highly similar in their morphology and also of the fact of their inter-incompatibility, though unilateral.

     

  • Comparison of varying pollen source on productivity of sour cherry (Prunus cerasus L.) cultivars
    23-26.
    Views:
    197

    Fruit set of five sour cherry cultivars (‘Újfehértói fürtös’, ‘Éva’, ‘Petri’, ‘Pándy 279‘ and ‘Csengôdi’) of eight years-old trees grown in Újfehértó, located in the Eastern north part of Hungary have been studied over two years (2008 & 2009). Following reciprocally cross-pollination, free-pollination, self-pollination (autogamy) artificial self-pollination (geitonogamy) were studied. The results show that both maternal and paternal parent cultivates had significant effects on the percentage fruit set. Significant differences have been found in fruit set among years and among pollination treatments. Fruit set of free-pollinated Pándy 276 cultivar was low and seasonally highly variable. The yield of this cultivar on self-pollinated flowers was nearly 0%, and in this treatment the maximum yields did not reach 10% in any of the examined cultivars. There was no significant relationship in the fruit set of free-pollination and natural self-pollination treatments.

  • Self fertility of pear varieties conditioned by natural self pollination (autogamy)
    110-113.
    Views:
    164

    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.

  • Blooming time of some apricot varieties of different origin in Hungary
    16-20.
    Views:
    325

    There are a number of self-incompatible and partially self-compatible apricot varieties which need cross pollination for suitable yield. We have to know their blooming time to select the appropriate pollen donor cultivars. The blooming period of 20 apricot varieties was observed in four subsequent years. Blooming time was affected by temperature conditions very much. Varieties studied were assigned to three groups according to their blooming time. The rate of overlapping of important variety combinations was observed. Sufficient overlapping of blooming period for safe pollination is usually ensured within the same group of varieties or between varieties of the neighbouring blooming time groups.

     

  • General principles in variety-association for intensive plantations of pomeceous fruits
    96-101.
    Views:
    160

    Under conditions of Hungary, more than 400 varieties of apple, pear and quince varieties have been observed for time of blooming and fertility relations in order to check the possibility of their use for intense plantations in different combinations with polliniser varieties. Low (below 3%) rate of self-fertility occurred at 65% of apple varieties. That partial self-fertility, however, is far from being sufficient to produce acceptable yield, thus allogamous pollination is absolutely necessary. The same is true for the rear and quince varieties grown in Hun­gary, too. The normal development requires the presence of viable seeds in the fruit set, most in quince, therefore, association of the right varie­ties is most important in that species. Apple and pear varieties are assigned according to their blooming time to 4, quince varieties to 3 groups. The yield of all three pomaceous species declines with the growing distance from the potential pollen source. In the intense plantations, the critical (maximum) distance to be observed is 20 m for apple and 15 m for pear and quince. In combining the placement of varieties, also the principles of a variety-specific cultivation are to be considered carefully. The double objectives are satisfied most by the system of Malus­pollinisers developed for intense plantations.

  • Floral biology of hazelnut (Review article)
    7-19.
    Views:
    211

    Floral biology of hazelnut (Review article)

  • Association of varieties in stone fruit plantations
    29-33.
    Views:
    166

    In the majority of Hungarian orchards of stone fruits, the planting distance is 6-7 m x 4-5 m. As many of the current varieties are self-incompatible, planting designs are applied to provide for adequate pollinisers. As long as differences in blooming time are small, i.e. 3-5 days at most, overlaps of blooming of the associated varieties are sufficient for fruit set.

    In sour cherry, one leading variety, Pándy, is self-incompatible and requires two polliniser varieties at least (Ciganyneggy or some sweet cherry varieties). Pándy is, moreover, cross-incompatible with the varieties Debreceni bőtermő, Kántorjánosi and Újfehértói fürtös being all of them self-fertile as most of new varieties recommended, by the way, for being planted to monovarietal blocks.

    Among European plums there are varieties registered as male sterile, self-incompatible, parially self-fertile and self-fertile, respectively. For the purpose of cross pollination, the choice of two varieties, at least, to be associated to any variety belonging to the first three groups, is recommended. The number of rows in blocks planted to self incompatible or male-sterile varieties should not be higher than 2-(4). Inter-incompatibility has been observed within the currently recommended assortment, between the varieties Cacanska najbolja and Stanley, only. Chinese-Japanese plums are scarcely represented in Hungarian plantations. Variation of blooming time in varieties is somewhat more pronounced, i.e. 5-8 days. There is but a weak tendency to self-fertility, thus practically, all varieties are considered as self-incompatible, thus the planting of two-row blocks for each of three varieties, at least, are recommended to be associated.

    Self-incompatibility and partially self-fertile apricot varieties are recommended to be combined with two polliniser varieties, at least, each planted to two-row blocks. The varieties Ceglédi óriás, Ligeti óriás, Nagykőrösi óriás and Szegedi Mammut are mutually inter-incompatible. Most of the peach varieties grown in Hungary are self-fertile, thus they are planted to large blocks, each. On sites threatened by late spring frost, it is recommended to plant (monovarietal) blocks of 4-6 rows at most. Cross-pollination may increase fruit set even in self-fertile varieties.

     

  • DNA-based determination of suitable pollinating cultivars for the pear cultivar 'Carola' (Pyrus communis)
    15-19.
    Views:
    132

    Pollen-limited fruit set has long been suspected in some relatively low-yielding orchards with the Swedish pear cultivar 'Carola'. Fruit was therefore harvested on 23 'Carola' trees in a commercial pear orchard. The seeds were germinated and five seedlings from each tree were sampled to determine which of the surrounding cultivars had been the most successful pollinators. Leaves of 'Carola', the 7 putative pollinating cultivars and the 115 seedlings were analysed with 6 RAPD primers. By comparison of the band patterns, paternity could be ascertained for 74 seedlings. The by far most successful pollinator was 'Clara Frijs' which had sired approx. half of the seedlings, followed by 'Herzogin Elsa', `Skanskt Sockerpiiron', 'Alexandre Lucas', 'Coloree de Juillet' and 'Doyenne du Cornice'. The latter is the maternal parent of 'Carola', and these two cultivars must therefore share one S-allele and hence can only be semi-compatible. In addition, 6% of the seedlings were in all likelihood derived from selling_ since they showed no bands that did not occur also in 'Carola'. Maximum distance between 'Carola' trees and suitable pollinators should not exceed 15-20 tn. Longer distances may produce a serious dearth of compatible pol­len as evidenced by the large percentage of seedlings derived either from selling. (25%) or from long-distance (> 40 m) pollen transfer (25%) when 'Carola' trees were surrounded by non-preferred pollinators.

  • Floral biology of plum (Review article)
    11-27.
    Views:
    153

    Floral biology of plum (Review article)

  • Nectar production of quince (Cydonia oblonga Mill.) cultivars
    87-94.
    Views:
    183

    Nectar production of six quince cultivars were measured during three consecutive years. The nectar production of quince can be regarded to be small compared to other temperate zone fruit tree species since quince flowers contained 1.07 ± 0.06 mg of nectar in average. The extreme values, however, ranged between 0.1 and 7.3 mg/flower and this indicated that the nectar production was highly variable. The distribution of the nectar production was definitely skew because low values were definitely much more frequent than the highest ones. Our findings do not corroborate the earlier statements on the high sugar concentration of quince nectar. We found some 21-27% sugar in average, only. The normal distribution of the sugar concentration also indicates that the typical sugar concentration may be between 20-30%. Accordingly, the sugar concentration of quince nectar is rather low compared to other temperate zone fruit tree species (except pear). There was a significant negative correlation between the amount of nectar and its sugar concentration in quince flowers in all of the three years of the study (r= -0.51, n=37, p<0.02 in 1996, r= -0.57, n=28, p<0.1 in 1997, r= -0.35, n=9 I, p<0.001 in 1998). No definite difference was established between the nectar production of quince cultivars. Nevertheless, one cultivar tended to produce less and two other ones produced somewhat more nectar in average than the rest of the 6 cvs investigated but the extreme values of nectar production of cultivars overlapped in most cages.

     

  • Some important growing characteristics of apple and apricot cultivars in two fruit growing regions in Romania
    51-56.
    Views:
    138

    The aim of this study was to determine some important growing characteristics of 5 resistant apple (Rajka, Rubinola, Topaz, Otawa and Goldstar) and 7 apricot (NJA 19, Goldrich, Harcot, Venus, Comando, Olimp, Cea mai buna de Ungaria) cultivars in two fruit growing regions in Romania from 2000 to 2003. Height of the apple trees (4-year-old tree) ranged between 1.96 m (cv. Topaz) and 2.39 m (cv. Rubinola). Diameter of the crown ranged from 0.96 m (cv. Goldstar) to 1.12 cm (cv. Rajka). The trunk diameter ranged from 3.5 cm (cv. Goldstar) to 5.0 cm (cv. Rajka). The surface of the trunk section was the lowest for cv. Goldstar (9.7 cm') and the largest for cv. Rajka (19.6 cm). Height of the apricot trees (4 years old tree) ranged between 2.69 m (cv. Venus) and 3.38 m (cv. NJA - 19). Diameter of the crown ranged from 2.59 m (cv. Comandor) to 2.77 m (cv. Cea mai buna de Ungaria). The trunk diameter ranged from 9.54 cm (cv. Goldrich) to 13.30 cm (cv. NJA - 19). Length of annual branches was the lowest for cv. Goldrich (45.1 cm) and the highest for cv. NJA - 19 (83.8 cm). Bud swelling of apricot trees began on 8 March for cv. NJA - 19 and ended on 11 March for the control cultivar (Cea mai buna de Ungaria). The blooming started on 16 March for cv. NJA - 19 and 27 Mach for the control cultivar. Duration of fruit growth was 89 days for cv. NJA - 19 and 128 days for cv. Comandor. When the temperature decreased to 1.5 °C (in 2001), percentage of viable pollen grains ranged between 48.86 % (cv. Olimp) and 91.57 % (cv. Venus). The germinating grains ranged from 31 % (cv. Olimp) to 90 % (cv. Harcot). Free pollination was the lowest for cv. NJA - 19 (29 %) and the highest for cv. Harcot (41%), while self-pollination ranged between 6 (cv. Olimp) and 11 % (cvs. Comondor and Harcot). Apple yield ranged from 16.65 t/ha (cv. Otawa) to 24.35 t/ha (cv. Rajka) and the differences varied from 4.45 t/ha to - 3.25 t/ha compared to the control varieties. Apricot yield ranged from 11.47 kg/ tree or 9.53 t/ha (cv. Cea mai buna de Ungaria), to 38.83 kg/tree or 27.34 t/ha (cv. Olimp) and the differences varied from 3 t/ha to 17 t/ha compared to the control varieties. Apple fruit weight ranged from 162 g (cv. Otawa) to 222 g (cv. Goldstar) and apricot fruit weight from 42.52 g (cv. Goldrich) to 68.38 g (cv. Comandor). Color, taste and aroma were very specific to cultivars.

  • Acceptance of artificial nesting sites by pollinating mason bees in commercial fruit plantations (Hymenoptera, Megachilidae: mixed Osmia cornuta and O. rufa population)
    43-46.
    Views:
    220

    During a four yeas long experiment a simple bee shelterswas found to be a propermethod to increase the size ofmixed natural populations of the early season Osmia cornuta and O. rufa under practical farm conditions. Instead of the number of pesticide applications the earliness of the flowering of the fruit species in the orchards was found to be themost important factor in the rate of acceptance of reed as nestingmediumby Osmias in the bee shelter. This relationship was negative and highly significant (r = –0.829, p<0.001). This means that much higher acceptance of artificial nestingmedia in bee shelters and consequentlymuch higher population increase of the two early seasonmason bee species can be expected in orchards with early than with late flowering fruit species. Mixed orchards or early flowering orchards surrounded by other orchards falling in bloom later consecutively may also be much favourable to mason bees because they can find continuous food (pollen) supply there for a much longer time during their period of activity than in orchards planted with a single fruit species and being apart from orchards of other fruit species.

  • Application of pollen mixing device in front of the hive entrance
    151-152.
    Views:
    123

    The model of a pollen mixing device was tested in sunflower culture in order to detect the effectiveness in helping the out-going honey bees to carry more and different varieties of pollen grains on the body and body hairs. This model is build from line hairs of brushes facing each other that can keep and release pollen grains. The brushes are functioning as pollen receiver-transmitter units. The effectiveness was tested by examining the number and the species of the pollen grains adhered to the bees passing through the entrance. The amount of pollen and the number of pollen species on the hive with the device was significantly higher than on the control hive.

    The data were analysed by variance analysis and significant differences were found according to the number and species of pollen grains between the incoming and outgoing bees.

     

  • Fruit drop: II. Biological background of flower and fruit drop
    103-108.
    Views:
    294

    The most important components of fruit drop are: the rootstock, the combination of polliniser varieties, the conditions depending of nutrition, the extent and timing of the administration of fertilisers, the moments of water stress and the timing of agrotechnical interventions. Further adversities may appear as flushes of heat and drought, the rainy spring weather during the blooming period as well as the excessive hot, cool or windy weather impairing pollination, moreover, the appearance of diseases and pests all influence the fate of flowers of growing and become ripe fruits. As generally maintained, dry springs are causing severe fruit drop.

    In analysing the endogenous and environmental causes of drop of the generative organs (flowers and fruits), the model of leaf abscission has been used, as a study of the excised, well defined abscission zone (AZ) seemed to be an adequate approach to the question. Comparing the effects active in the abscission of fruit with those of the excised leaf stem differences are observed as well as analogies between the anatomy and the accumulation of ethylene in the respective abscission tissues.

  • Inheritance of blooming time in walnut, with regard to the property of reproductional autoregulation of species
    118-122.
    Views:
    129

    A great number of crosses have been made with Hungarian and foreign varieties as partners to breed improved varieties. This species shows a particular trait, namely the autoregulation of fruit set, which affects considerably the productivity of commercial orchards. Thus the inheritance of the blooming time of the male and female flowers has been explored for several years in the progenies.

    It has been stated that

    - the feature of the partners does not turn up predictably in the progeny,

    - it is most important to take into consideration the blooming time class of both, male and female flowers in planning associations of varieties for commercial orchards.

    - in years of irregular spring weather the stability of the blooming time of the variety or in other words the deviation of the actual blooming time of variety from its characteristic blooming-time class is also very important.

     

  • Flower constancy of honeybees (Apis mellifera L.) to blooming pear plantations
    81-85.
    Views:
    159

    Studies were made on the composition of pollen loads of honeybees captured at the flowers of blooming pear trees in pear plantations. Also the foraging behaviour of honeybees was observed. Overwhelming majority of honeybees visiting the flowers of 13 pear cultivars in 1996 were pollen gatherers (95.6 per cent). Proportion of pure nectar gatherers was as low as some 3.7 per cent and no more than 0.7 per cent performed mixed behaviour. The analysis of pollen loads of bees collected at pear flowers in blooming pear plantations showed that fidelity was as high as 89-90 per cent towards pear, higher than for another fruit species in other studies. Even those plant species that are regarded to be strong competitors of blooming fruit trees in the literature (Taraxacum officinale, Stellaria media, Lamium purpureum) were scarcely represented in the loads. Accordingly, honeybees can be much more important and more effective pollinating agents of pear cultivars than generally believed.

     

  • Floral biology and fertility of apricot
    9-15.
    Views:
    171

    Floral biology and fertility of apricot

  • Impact of foliar fungi on dogroses
    23-30.
    Views:
    185

    Wild roses of the section Caninae, commonly known as dogroses, have been described as more disease tolerant than ornamental roses and could therefore become valuable for breeding improved rose cultivars. Two fields with dogroses, one with plants obtained by open pollination in wild populations, and one with plants obtained from intra- and interspecific crosses, were evaluated for blackspot, powdery mildew, rust and leafspots in the autumn of 2005. Symptoms of the different fungi on different dogrose species were carefully evaluated in a microscope and documented by photography. Interestingly, almost no symptoms of powdery mildew were found in either field, although the fungus infected wild roses of a different section in a field closeby. Surprisingly few symptoms were found also of blackspot, and they differed considerably from those found on ornamental cultivars, indicating a lower susceptibility in dogroses. The most important fungal disease in 2005 was rust, followed by leafspot symptoms. The latter were apparently caused by Sphaceloma rosarum and Septoria rosae which can be properly discriminated only in a microscope. The investigated dogrose species and their progeny groups varied significantly in disease susceptibility and in the appearance of encountered symptoms but there was no evidence of major resistance genes, except possibly in Rosa rubiginosa which did not show any symptoms of Septoria. In 2006, a subset of the plant material in Field 1 was evaluated to check for consistency between the years. Leafspots had overtaken rust as the most important disease but results were otherwise very similar to those of 2005.

  • Nectar production of pear (Pyrus communis L.) cultivars
    67-75.
    Views:
    232

    Detailed studies were made on the nectar production of 44, 16 and 18 pear cultivars, respectively, in a cultivar collection of pear during three consecutive years with highly different weather in the blooming. Results clearly show that pear does not necessarily produce small amount of nectar as stated in the world literature. In fact, pear can produce extremely high amount of nectar sometimes much higher than other temperate zone fruit trees species but its nectar production is highly subjected to weather, first of all to air temperature. Low nectar production seems to be more frequent than high one and cold weather can prevent its nectar production at all. On the other hand, results corroborate to the earlier statements on the low sugar concentration of pear nectar. There is a highly significant negative correlation between the amount of nectar produced by pear flowers and its sugar concentration (r = -0.52, n = 291, p< 0.001 for 1996, r = -0.34, n = 197, p< 0.001 for 1998). Sugar concentration in individual flowers may be up, to 40% in exceptional cases but generally it is well below 20%. Very high figures for sugar concentration in pear nectar at the literature seem to be incomprehensible. In contrast of some earlier statement in the literature no real difference could be established in the nectar production of pear cultivars, based on much more measurements than in earlier studies. Very low sugar concentration in pear nectar can explain the fact that the overwhelming majority of honeybees are pollen gatherers at pear trees even in the case of exceptionally high nectar production.

     

  • Path coefficient analysis of environmental factors influencing flight activity of Apis florea F. and seed yield in carrot (Daucus carota L.)
    87-92.
    Views:
    118

    Foraging ecology of insect pollinators visiting carrot flowers (Daucus carota L.) was studied in relation to five environmental variables. The dwarf honeybee, Apis florea L., was the most abundant flower visitors and comprised more than 94% of the total flower visiting insects. Commencement of flight activity occurred when a minimum threshold of environmental variables was surpassed while the cessation was governed mainly by decline in values of light intensity and radiation. In between the commencement and cessation, the foraging population correlated significantly and positively with air temperature, light intensity, solar radiation and nectar-sugar concentration and negatively with relative humidity. Path coefficient analysis, however, revealed that direct effect of temperature was high and positive followed by light intensity and solar radiation while the direct effect of relative humidity was high and negative. The direct effect of nectar-sugar concentration was negative and negligible. Evidently, path coefficient analysis gave a more clear picture of effects than did the simple correlation analysis. Apis florea on an average visited 1.14+0.23 and 22.78+2.57 umbels and flowers/min, respectively during different hours of the day. Furthermore, the insect pollinated plots produced significantly more seeds with heavier weights than those isolated from insect visits.

  • Estimation of plum and prune cultivars with morphogenetical traits
    147-152.
    Views:
    182

    The author post few years organizes the plum breeding program. He uses up earlier elaborated morphogenetic and productive characteristics and traits, already on such basis their selected 21 cultivars in the pomological garden at Cegléd. The Hungarian plum assortment and offer very specific and tight, thus that they endeavor, that the selection before then flare. There are indicating already only the perspective cultivars in present paper on basis of gathered data one decade underneath. Paralleling control was three type of used (Besztercei szilva Bt. 2, Green gage and Stanley). 12-sort trait according to were compared the cultivars. The productivity-biological standpoints without, the open pollination and pollen germination, over and above that the ripening on date big differences appear. The near future the 'C. 1501' (Yellow Besztercei), 'Ontario' and `Mirabelle de Nancy' (yellow plums), the yes untimely `Precoce di Guigno' (red plum), the very well abundant 'C. 940' and Victoria (lilac plums), over and above that 'Beregi datolya', ‘Révfülöpi’ and `Szarvasi' (blue plums) cultivars setup suggest. The demonstrated cultivars out of further give for deputize value the Precoce di Giugno, as earliest ripening and the 'Beregi datolya' but the at the latest ripening.