Pollen morphology of fruit species

Size and surface morphology of pollen has been studied in 87 twit varieties of 10 fruit species during the period of 1990-1995. No preceding work of that type came to our knowledge, yet.

The samples comprised a wide variety of cultivars included male sterile, self-incompatible, partially self-fertile stone fruits, diploid and hexaploid plums, diploid and triploid apples.

The large number of species and varieties facilitated the comparison of items within and between the respective species.

It was stated that the size, shape and surface morphology of pollen is genetically determined and those data, combined with other variety characters, are suitable for the classification and distinction of varieties.

In assessment of pollen size and shape, their moisture content is crucial. The major diameter of the swollen pollen as well as the length and width of the dry grains are characteristic to species and/or to variety.

The width and shape changes largely with moisture content. Large grains are proper to quince, apricot, peach and almond, medium sizes are found in apple, sweet cherry, sour cherry, European plum, whereas small size is typical to Japanese plums.

The low number of varieties studied does not allow conclusions concerning differences within pears, quinces and almonds as species. In the rest of species, valid differences have been registered as between varieties.

Within species, as apple and plum, the effect of ploidy (i.e. number of chromosomes) was expressed in the size of their pollen. In stone fruit species, the correlation between size. of anthers and size of pollen grains was positive.

Genetic relations between the self-fertile sour cherry varieties of the Pándy type (Debreceni bőtermő, Kántorjánosi, Újfehértói fürtös) as well as the self-incompatible apricots of "giant" fruit size are supposed to be analysed by pollen studies but there did not turn out any decisive conclusion, yet. Other characters also should be considered.

The assembly of pollen characters is decisive in the determination of the variety. The ratio of empty pollen grains, the grain size and the density as well as the size of the pits on the surface are best suited to distinguish pollen lots.


The morphology of stigmata in stone fruit species

The morphology of the stigma has been studied in 50 varieties belonging to 6 stone fruit species. The majority of samples had elliptical stigmata with some exceptions with circular form (Duane, Tuleu gras). The surface of the stigma is papillary, flattened in side view (sweet cherry) or bulging (apricot, peach). The suture of the stigma is clearly visible as a depression and the varieties may differ in this respect.

The size of the stigma depends highly from the season, although the varietal differences are maintained. The dimension of stigmatic surface is characteristic for the species expressed in square millimetres: sweet cherry 0.92 to 2.91; sour cherry 1.64 to 2.48; plum 0.83 to 1.80; oriental plum 0.53 to 1.15; apricot 0.57 to 1.69 mm2.

The size and morphology of the stigma changes according to varieties too, and it may used in description and identification of varieties. No correlation has been found between the size of stigma and the fertility relations (self-fertility or self-incompatibility) of the respective varieties.


Effect of life cycle on the production of mullein (Verbascum phlomoides L.)

Aim of the present investigations was the optimalization of the production of the annual cultivar `Napfény' of Verlxiscum phlomoides L. Quantitative data on morphology (growth, leaf and flower size, branching) yield and content of active materials (mucilages, flavonoids) were studied at six sowing times.

We established, that sowing time may be one basic factor in the production of the annual variety. The major yield was obtained by sowing either late autumn (end of October) or early spring (middle March). At these plots the fresh mass of the flowers was 257-288 g/plant, the drug mass 28-29 g/plant, by 45-70% more than that of the mean of other treatments.

It was established, that under optimal cultivation conditions the annual form of mullein may reach higher individual yields than the plants of the indigenous wild growing population.

Agronomic evaluation of different lettuce (Lactuca sativa L.) varieties under unheated plastic tunnel

Among the leafy vegetables, lettuce (Lactuca sativa L.) is the most widely grown species in the world. Wide ranges of physical properties of the products are used to assess the degree of maturity. In this study, different lettuce varieties were grown under an unheated plastic tunnel in springtime. We evaluated the agronomic properties of different lettuce varieties, evaluated the condition of the plants, and determined the bioactive substances. Larger head weight can be achieved by the ‘King of May’ butterhead (259.31 g) and ‘Great Lakes 659’crisphead (220.40 g) genotypes. A very strong correlation (r = 0.995) was observed between the lettuce head index, and leaf index and both had a strong positive correlation (r = 0.828 and 0.760) with NDVI. The highest SPAD values were measured for cos lettuce ‘Romaine lettuce’ (44.01) and iceberg lettuce ‘Great Lakes 659’ (42.71). However, these genotypes showed the highest (9.52%; 8.74%) dry matter content, too. The red leaf variety 'Lollo Rosso' had the highest total polyphenol content (181.53 GAE/100 g FW).  Among the evaluated properties, iceberg lettuce showed favorable morphology, plant condition, and good dry matter content. In addition, between the loose-leaf lettuces, the red leaf lollo type was outstanding with bioactive content.

Morphological examination of Hungarian apricot rootstock varieties

Apricot seedlings are one of the most widely used rootstocks in apricot growing of Hungary. The National List of Hungary contains 7 apricot seedling rootstocks varieties. The production of apricot graft on seedling rootstock takes 3 years from the seed production to the complete graft and requires more space. It is important to provide the trueness to variety name during this process. In the genus Prunoideae not only the plant but also the stone should have typical characteristics. It seems to be useful to examine the morphology of stone. The observed varieties were 'Tengeribarack C.1300', 'Tengeribarack C.1301', 'Tengeribarack C.1650', 'Tengeribarack' C.1652', 'Tengeribarack C.145', 'Tengeribarack C.1426' and 'Tengeribarack C.2546`.1t seems to be the most suitable characteristic to make a distinction between these varieties by stone, the ratio height of stone to lateral width of stone, the ratio of height of stone to ventral width of stone, the ratio of lateral width of stone to ventral width of stone and the ratio of ventral zone to ventral width. From not measured characteristic seems to be most utilizable to make distinction: the fusion of dorsal groove margins, the shape of apex, the presence of a mucro of the apex, the shape of stalk end in lateral view and the texture of lateral surfaces.

Ecological drought resistance and adaptability of apple varieties

For adequate yields in apple plantations, during the long growing period of the fruit primordia, one of the decisive factors is water supply. Indicators of stress are valuable signs for the diagnosis of drought and necessity of watering, i.e. planning the irrigation of plantations. The aim of the present study was to find reliable signs of water stress on apple trees and at the same time conclude on the drought tolerance of different varieties. The plantation of apple varieties grafted on various stocks and cultivated according to different systems (irrigated, non irrigated, integrate and biological) has been examined continuously by leaf analysis. Along the period of growing fruits, measurements were made in the field, then the leaf samples were analysed in the laboratory for composition of pigments, carbohydrates and antioxidants, as well as the histology of the tissues checked. Without irrigation, the mean leaf mass and the relative chlorophyll content (SPAD) of the variety Idared on M4 stocks increases beyond the values of 50 SPAD, whereas on M26 stock and integrated system, it declines. In the collection of varieties, grown according to the „integrated” system, during the development of fruits, ‘Gála’ and ‘Remo’ varieties have been affiliated to the “less susceptible” group regarding drought tolerance because of the leaf morphology, structure and content of SPAD and antioxidants. However, ‘Idared’ and ‘Jonagold’ belong to the “susceptible” group. To the same group are ranged the ‘Akane, Red Rome vanWell, Pink Lady’ varieties. Those varieties reacted to a short period of drought by increased production (content) of carbohydrates. Regarding changes of carbohydrate content ‘Greensleeves’ and ‘Ozark Gold’ varieties belong to the moderately water dependent (requiring) group. In the field, SPAD-tests facilitated the measurement of nutrient-uptake and incorporation, which is proved by the tight correlation between the data of SPAD and the increment of leaf weight (r=0.76–r=0.88), however, this depends on the variety too. SPAD is an indicator of water supply and is related with the density of stomata, cannot used for the selection of water-exigent varieties but for (drought) tolerant ones. In integrated culture, the (drought) susceptible varieties display (water-soluble) hydrophilic and lipophilic antioxidants (ACWand ACL resp.) the quantity of which may have some role in drought tolerance.

Agronomic and alimentary evaluation of elder (Sambucus nigra L.) genotypes selected from natural populations of Hungary

The black elder (Sambucus nigra L.) is a native plant in Hungary represented by extended and very variable populations. Cultivation of elderberry started during the late 90-ies because of the growing interests of the processing industry. High anthocyanin content, nutritive value of the berries and aromatic compounds of the flowers have been the esteemed constituents.

At the moment, there are about 3000 hectares elder plantations in Hungary, which is more than of any of the other European countries. Unfortunately, the cultures are planted to the Austrian selections of Haschberg, in spite of the fact that about 10-15 other selections of other foreign countries have been registered and planted elsewhere. In addition to that, the wild population of Hungary may offer a precious opportunity of further selection. Since 1970, Aladár Porpáczy at Fertőd and the Department of Fruit Growing of the former University of Horticulture in the 1980-ies started the selection in Hungary too.

The present study deals with 7 genotypes, their morphology of berries and inflorescences. Results are concentrated on four genotypes: Szcs­1, Szcs-2, Szcs-3 and Szcs-5, which are all earlier ripening than the Haschberg varieties, and are superior in characters of fruit and inflorescence.

Apple powdery mildew caused by Podosphaera leucotricha: some important features of biology and epidemiology

In this review, some important features of biology and epidemiology are summarised for apple powdery mildew (Podosphaera leucotricha). In the first part of the review, the geographical distribution or the pathogen are discussed, then the morphology and taxonomy of the causal organism are described. Disease symptoms or apple powdery mildew are also shown and then host susceptibility/resistance is discussed in relation to durability of resistance. In the second part of this review, the general disease cycle of powdery mildew on apple are demonstrated and some basic features of powdery mildew epidemiology (such response of the pathogen to temperature, relative humidity, and rain as well as spore production, spore dispersal, diurnal patterns and temporal dynamics of the pathogen/disease) are also given on apple host.

Fungicide resistant Trichoderma strains causing compost infection in shiitake production

Trichoderma infection represents the major problem of shiitake production in the growing house of the Research Institute at Kecskemet. Heavy infections occur mainly on the compost before spawn run. All the isolated strain belongs to the species Trichoderma harzianurn, but morphology of the colony indicates that there are more strains liable for the infection. Source of infection remained unclear but the Trichoderma strains can be considered as weed moulds rather than true pathogens of shiitake. All the Trichoderma isolates showed unusual high degree of resistance to fungicides.

Comparative study of heirloom tomato varieties

The study examined the health status, growth type, berry morphology, berry quality, and gastronomical value of 60 heirloom tomato lines. In the middle of June, the level of virus infection was medium in the plant stock according to the assessments. 21% of the lines did not show symptoms of virus infection. During the vegetation period, the major fungal diseases were Alternaria by the middle of August and Phytophthora from the beginning of September. In spite of the fact that no fungicides were applied, 13% of the lines were healthy and 36% showed medium infection at the end of August. Half of the lines had a strong, 23% of the lines had a medium growth vigour. The majority (74%) of the lines showed strong or medium lateral shoot growth and only 7% of them proved to be less prone to branching. In spite of the rapid growth, 20% of the lines had a weak main stem, the majority of the lines had a main stem medium strength. The different shapes occurred in different colours, in addition to the traditional red colour (53%), there were orange, yellow, wine-red (blackish), lilac, green, almost white or multicoloured varieties. Unfortunately, most of the lines were prone to longitudinal or circular cracking of the berries. Based on the first experiences, all tested variety types had more favourable utilization characteristics then the traditional tomatoes. Varieties with a thick flesh and harmonic acid/sugar ratio such as some of the ox-heart varieties are especially valuable. For drying, the elongated types proved to be the best. The hollow tomato is the most special type which can be utilized most diversely. It is especially suitable for making white tomato soup and, “Concasse" due to its easily removable placenta rich in jelly materials and its thick flesh. In addition, it can be used for preparing stuffed tomato.

Comparison of Xanthomonas arboricola pv. juglandis isolates from walnut trees grown in Romania and Hungary

Among diseases that affect walnut, bacterial blight is considered the most important one in all walnut growing areas both from Hungary and Romania. For the determination of susceptibility/resistance of walnut cultivars in our posterior work planned, 61 bacterial isolates were collected from walnuts showing symptoms of blight, with the purpose of isolating Xanthomonas arboricola pv. juglandis (Xaj). The characteristic Xaj colonies, frequently present as saprophytes in the infected plant tissues, were separated from other bacteria according to their morphology, yellow colour, hydrolysis of starch, and oxidation of glucose. All isolates were tested for pathogenicity by hypersensitive reaction on tobacco leaves (Nicotiana tabacum L.), bean pods (Phaseolus vulgaris L) and unripe nuts (Juglans regia L.). Determination of taxonomy of the selected isolates denotes a possible subdivision (races, biotypes) of Xaj occurring in different geographical areas, API 20NE and API 50CH kits were used. Hungarian and Romanian strains showed a high degree of similarity of carbohydrate utilization but slightly differed from the type strain. All were Cu-sensitive.

Comparative study of different fertile groups in plums

The plum traditional fruit species in Hungary, several local cultivars was born in the different grower's districts. The author that investigated, that are morphological differences between an odds find self-fertile, self sterile (with functional stamens) and male sterile plum cultivars. For it thought about main questions of a scientific debate sown up and the study this way gave reactions totalize. There were in three fertile groups 8-8 type of feature plum cultivars in periods of 1992-2001, respectively 1993-1999. It was founded by author big odds found the troops on the basis of 9 traits between. Pistil length of self sterile cultivars very typical, such as sesquipedalian flower peduncle of the self-fertile plums and the hypoandry of male sterile cultivars. The relative stamen number and the pollen viability as well significant odds gave.

The average fruit mass and sharka infection of self-fertile plums this troops extreme work. According to cultivar's averages the shark symptoms standard the right correlation the singular traits, but those one part of her with each other not shown connection.

The annuity potencies underdeveloped the troops behind and the troops within cultivar's differences had case significance. The results usable the male sterile cultivars and progeny further its investments.

Apple powdery mildew caused by Podosphaera leucotricha: some aspects of biology

Apple powdery mildew (Podoshphaera leucorticha) occurs wherever apples are grown. One of the most important fungal disease of apple which causing severe econimic loss on susceptible apple cultivars. Biology of the pathogen is widely investigated all over the world in the past 100 years. In this review, a summary from this enormous research is made for biology of apple powdery mildew in the following aspects: geographical distribution, morphology, taxonomy of the causal agent, symptoms, host susceptibility, resistance durability and disease cycle.

Virus and virus-like diseases of grapevine in Hungary

Viruses and viroids are submicroscopic infectious particles which can cause disease symptoms on grapevine. These parasites are depending completely on the energy metabolism of the plant cell. To enter the host cell plant viruses depend on injuries or on transmission via invertebrates (insects, nematodes, etc.). Viruses are classified by many characters including particle morphology, host range and information content of the genome. At present about 70 viruses including 7 viroids infecting grapevine are known. In single or mixed infections they are potentially detrimental to the quality and quantity of grape production in any growing area of the world. Some viruses can cause severe economic damage in vineyards. In Hungary many important viruses and viroids have been detected in grape. This review summarises characteristics of viruses and the results of detection and characterization of virus and virus like diseases of grapevine in Hungary. The identification of the causal agent, its transmission, geographical distribution and the development of the diagnostic methods are also discussed.

Morphological and phenological properties of sour cherry varieties grown in Hungary and their inter-incompatibility relations

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.


Long term investigations of flowers and leaves on mainly non-domestica plums

The author dealt with plum species representing different eco-geographic areas by their genetic adaptation and their hybrids, as European (P. domestica, P. italica, P. cerasifera), Asian (P. salicina, P. simonii, P. ussuriensis), American (P. americana, P. besseyi, P. munsoniana, P. tomentosa). The rootstocks of the trees examined were seedlings of C. 679 myrobalan with the exception of Laroda and Santa Rosa II, which were grown on three different stocks: seedlings of C. 174 myrobalan, C. 449 bitter almond and C. 471 sweet almond. The size of peduncle, length of pistil, stamen number per flower, relative stamen number (SN/PL) have been suitable for description and distinction of varieties. Similarly shape of leaves, length of petiole, length and width of blade helped the identification.

The ratio of the dimensions of leaves, length of petiole and of leaf blade, also contributed to the distinction of European, Asian and American plum species, notwithstanding their relations with ecological conditions as well as historical, technical properties, pomological features, etc. Computed indicators (relative stamen number and shape-index of leaves) also have been useful data.

Significant correlations have been found between colour of nectaries and mean values of variety-groups. The potential values of non-European varieties for purposes of commercial production could be forecasted from the point of view of quality, ecological, pomological as well as market value. It is important, however, to know the effect of the rootstock and growing site as well as their interaction, on the one hand, whereas the resistance or tolerance of the varieties as limiting factors, at least to the sharka (Plum pox) virus, Xanthomonas pruni, on the other hand (cf. Surányi & Erdős, 2004a and 2004b).

Selectivity of the oriental fruit moth sex pheromone trap in peach and apricot orchards

One of the most important pests of the stone fruit orchards is the oriental fruit moth (Grapholitha 1110/esta B.). Chemical control targeted against the young larvae is the most effective way of protection. so the ti ming of treatments has to be based on the observation of emergence. Emergence may be monitored with sex pheromone traps. It is already known from former publications, that the traps for oriental fruit moth are also effective in the case of the plum moth (Grapholitha f1111ebra11a Tr.), which external morphology is very similar to the oriental fruit moth. As the emergence of the oriental fruit moth in peach and apricot orchards has not been observed in detaib in Hungary, we started a s1Udy in this field. Our aim was to measure the selectivity of the sex pheromone traps. On the basis of examining more than 5000 males caught and the investigation of male genital ia. it could be established that the pheromone traps. Csalomon and Deltastop, for oriental fruit moth, caught the plum moth in the same ratio. The ratio of the oriental fruit moth and the plum moth trapped in the peach orchards was I: I . while in the apricot orchards the number of the caught plum moth males was seven times as many as that of the oriental fruit moths. Consequently, it can be established that data based on oriental fruit moth trap catches can not be used without additional investigations of genitalia for the prediction of larval hatch. The selectivity of the plum moth trap. used as a control. was acceptable in both orchards.

Inter-incompatibility of self- incompatible apricots and their varietal properties

There are four apricot varieties grown in Hungary derived from local selections known to bear fruits of giant (60 - 100 g) size: Ceglédi óriás, Nagykőrösi óriás, Szegedi mammut and Ligeti óriás. Being morphologically similar, they seem to be closely related to each other. The detailed study of the morphology (of leaves and fruits) and phenology (of blooming and ripening dates) as well as the fertility relations was aimed to find out the degree of kinship between the varieties in question.

It was stated that the value of morphological traits is variable from the taxonomic point of view. The most important signs of common origin were the time of blooming and the leaf size. Less valuable are the date of m:iurity and the size of fruit because of their variability. In the literature Satin') & Nyeki (1991) published the first proof of inter-incompatible relation between apricot varieties. This should be considered as an argument of close genetic relation between those "giant" varieties of apricots.

The first three varieties. Ceglédi óriás, Nagykőrösi óriás and Szegedi mammut are closer related in blooming and ripening date, as well as in size of fruit to each other than the variety Ligeti óriás.