Impact of boron foliar fertilization on annual fluctuation of B in sweet cherry leaves and fruit quality
27-30.Vol 14No 32008
The goal of the study was to examine response of sweet cherries (Prunus avium L.) to boron (B) fertilization. The experiment was conducted during 2005-2007 in West Hungary on mature cv. `Germersdorfi 3' grafted on Prunus mahaleb rootstock. Sweet cherry trees planted on a calcareous chernozem soil. Trees were foliar-fertilized with B. Foliar B spr...ays were performed: (1) in the spring, at the stage of white bud, beginning of flowering (B1), and (2) repeated 5 weeks after full bloom (B2). In each of spring spray treatments, B was applied at a rate of 0.15 kg ha-I. Trees untreated with B served as a control. The results showed that B fertilization had effect on B concentration in leaf tissues, mostly after ripening. B was present significantly higher amount in leaf in treated samples after ripening. Mean fruit weight was slightly increased by B fertilization. Fruit sensitivity to cracking was not influenced by B fertilization. Nevertheless, from our data it can be conclude that the sensitivity of fruit to cracking is improved when the fruit is riper, the fruit density and fruit weight are higher. The soluble solids varied between 15.0 and 15.9% according to the treatments. Our results for the monosaccharides investigated varied between 5.1 and 7.2 as glucose and fructose as well. Galactose and sucrose was detected very small amount in the unprocessed cherries. Applied B treatments increased sugar contents but decreased organic acid contents in sweet cherry fruits. It is concluded that under conditions of this experiment, B fertilization can be recommended in sweet cherry culture to improve fruit quality and their appearance.
59-67.Vol 12No 22006
The basic conditions of fruit set (synchronic bloom, transfer of pollen, etc.) still do decide definitely the fate of the flower in spite of the best weather conditions. Beyond a set quantity of fruits, the tree is unable to bring up larger load. A system of autoregulation works in the background and causes the drop of a fraction of fruits in spit...e of the accomplished fertilisation and the equality of physiological precedents. This study discuss this physiological process based on the international specific literature. The further development of fruits maintained on the tree depends mainly on the growing conditions (e.g. water, supply of nutrients, weather adversities, pruning, fruit thinning, biotic damages, etc.), which may cause on their own turn fruit drop especially at the time of approaching maturity.
Floral bud development, blooming time and fertility relations of some Romanian apricot varieties in Hungary
41-43.Vol 6No 32000
Due to the geographical situation of Hungary the introduction of late ripening apricot varieties holds great interest. In apricot production floral bud development during winter, blooming time, and the fertilisation properties are important factors. These characters were studied in six late ripening Romanian apricot varieties (Callatis, Comandor, ...Litoral, Selena, Sirena, Sulmona) in Szigetcsép representing the northern site of the lowland growing area. During the mild winter of 1997/98 the dynamics of floral bud development in the Romanian varieties was a few days slower during the whole examination period compared to Gönci magyar kajszi. Their meiotic divisions occurred between 1 and 5 February. Next winter the meiotic division started later at 28 February, due to the cold weather. In these conditions the dynamics of bud development was similar in all the varieties. Averaged over seven years blooming of the Romanian varieties started 1-3 days later than in Gönci magyar kajszi. All the Romanian varieties showed self-fertility to some extent, however, application of other pollen donor sources is necessary for the safety of production, with the exception of Callatis.
45-48.Vol 20No 3-42014
The objective of thsi study was to compare economic aspects of superintensive and intensive apple production.According to our results, conclusions and recommendations regarding the establishment of superintensive orchards are the followings: A yield of 60 tons per hectare in the average of the mature years provide a quite late payback, in this way... yield losses should be avoided in the plantation of such a huge capital requirement. When yield losses happen, which cannot be avoided or may be avoided only in a limited way, up to 65 to 70 tons per hectare yield should be reached even in good years, in order to yield the average 60 tons per hectare in the long run. In this case yield losses from production technological mistakes must not be arisen. Inputs and professional expertise should be used in a maximum way in order to reach yields ensuring profitable production. Investment subsidies may ensure safer return. The return of a superintensive orchard from totally own sources may be risky under the domestic marketing conditions and selling prices, it is strongly uncertain.
111-113.Vol 17No 4-52011
In Hungary, natural conditions are optimal for growing plums. In spite of that, plum production was not a successful business in the past years. The reasons of it are, first of all, the utter fluctuation of yields and of the producer’s prices, increment of direct costs of production, dwindling incomes and uncertainties on the market. Serious pro...blems are caused by the high rate of aged plantations, which are not counterbalanced by new plantings. Decisive is the “loose” ranging of the branch by the Union regarding plum production, which is expected for the sake of enlarging production and markets. Our aims are to analyse the management of the eight-year-long period, 2002-2009, and the fate of components of husbandry. The results presented are means of an utterly heterogeneous population of enterprises, being hardly suitable to make actual decisions, but they may enlighten upon challenges and recognise tendencies within the branch.
39-43.Vol 16No 42010
Sweet and sour cherry need 550–600 mm yearly precipitation. The critical period is 1–1.5 month after flowering, it is normally between 15.April – 15. June in Hungary. The rain induced fruit cracking is also a critical and costly problem for cherry growers. Fruits grown under arid conditions are less resistant against rainfall during harvest ...and up to 50–60% crack damage may occur. A computer program was developed to calculate the precipitation related production risks of sweet cherry. Focus of the research was Zala county. Spatial distribution of precipitation was compared in two directions (East and North of Zala county) based on the data of meteorological stations. The first results indicate that the developed method estimates the risks quite well, compared to the farm experiment results. The developed computer program can be parameterised according to the user’s requirements, this allows to take into account the real variety structure of a given orchard.
99-101.Vol 13No 32007
Determination of flower microphenology for selecting the suitable pollinizer for sour cherry cultivars is of significant importance. In order to study the flower microphenology of Hungarian sour cherry (Bőtermő, Érdi jubileum and Cigány) cultivars in Mashhad climatic conditions, an experiment was conducted in I998. 1999, 2005 and 2006, using a... completely randomized design with ten replications. The phenological stages were determined from before opening up to browning phase of stigma. Duration of pollen shedding, stigma receptivity and climatic factors were measured. The relative time of flowering between cultivars varied from year to year. The data indicate, the thermal variation strongly contributes to significant differences in duration of stigma viability, although there wasn't a significant difference between cultivars in anther dehiscence period. Phenological stages of flowers are highly affected by meteorological factors in various years.
81-85.Vol 9No 3-42003
Matricaria recutita L. is a traditional medicinal plant in Hungary and its drug is known as „Hungaricum", world-wide. Plant samples and seeds were collected from 12 different habitats of three significant geographical regions of Hungary in 2001. Morphological, production biological and chemical properties of samples were examined. In relation to... the morphological characteristics, a negative correlation (r= -0.75) could be observed between the average height of the plants (height of flowering shoots) and the pH value of the soil. According to the composition of the essential oil, the populations accumulating typically chamasulene (10-20%), a-bisabolol (30-50%) or bisabolol-oxid (30-50%) could be completely distinguished. Concerning the flavonoid composition the quantity of apigenin-7-glucoside was outstanding in the populations originating from the Great Hungarian Plain, it has reached the concentration of 1.8-2.8 mg/g, while the samples collected in Transdanubia could be characterised by much lower level of apigenin-7-glucoside (around 1.5 mg/g).
79-81.Vol 5No 3-41999
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 phe...nology (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.
15-18.Vol 17No 4-52011
In modern and healthy diets antioxidants play an important role providing natural defence against serious diseases. Therefore it is recommended to include fruits and vegetables having high antioxidant capacity in daily diet in a due course. Apricot is one of the fruits receiving an increasing attention in this field. This study was conducted to in...vestigate the composition and content of fat-soluble carotenoids and tocopherols in different varieties of apricot using recently developed liquid chromatographic methods. Also it was aimed to compare organic and integrated farming in their effect on carotenoid and tocopherol content of the fruits. The results showed that apricot fruit are rich in vital carotenoids and bioactive tocopherols with significant variation between different varieties. The organic farming had favourable effect on the level of the major carotenoids and depending on variety this technology either increases or does not have significant influence on vitamin E content.
Acceptance of artificial nesting sites by pollinating mason bees in commercial fruit plantations (Hymenoptera, Megachilidae: mixed Osmia cornuta and O. rufa population)
43-46.Vol 16No 32010
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 th...emost 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.
High antioxidant - and anthocyanin contents of sour cherry cultivars may benefit the human health: international and Hungarian achievements on phytochemicals
45-47.Vol 12No 32006
Evidence suggests that a diet with high fruit and vegetable consumption may decrease the risk of chronic diseases, such as cardiovascular diseases and cancer, and phytochemicals including phenolics, flavonoids and carotenoids from fruits and vegetables may play a key role in reducing chronic disease risk. Recent research has proved that sour cherr...y (Prunus cerasus L.) is a valuable natural source of some bioactive compounds important in human health preservation. According to the published data, the most important biological effects of sour cherry are connected — directly or indirectly — to their endogenous antioxidant behaviour as well as to their specific pattern of anthocyanin components. In the present work, we measured the total antioxidant capacity of some Hungarian sour cherry varieties in combination with their anthocyanin-, and vitamin-C content. In 2003, twelve clones were selected and grafted from a local sour cherry population called "Bosnyák" sour cherry grown in small home gardens and farms of the village Csengod (Great-Plain Region, South Hungary). Other Hungarian sour cherry varieties, i.e. cv. Újfehértói fürtos, cv. Érdi bőterrnő, cv. Debreceni bőterrnő, cv. Csengődi and cv. Kántorjánosi served as a control.
109-113.Vol 6No 32000
The composition of floral nectar in sour cherry cultivars studied in 1997 at Újfehértó was in agreement with our previous data, the three most frequent sugar components being glucose, fructose and sucrose. Nectar secreted at night is generally more diluted than nectar produced during the day. None of the nectar samples produced at night reached... the threshold value (100 mg/ml) of bee visitation. In the majority of cultivars the difference in concentration between night and day nectar is not too high, but in two cultivars, 'Korai pipacs' and ‘Újfehértói fürtös’ the difference is quite significant. Most sucrose was found in the nectar of cvs. 'Érdi jubileum' and ‘Újfehértói fürtös’, but a high amount of sucrose was measured also in the flowers of 'Korai pipacs' and 'Meteor USA'. Nectar concentration varies from opening of the flower to petal fall to a smaller or greater degree, depending on the given cultivar. From the 9 sour cherry cultivars studied ‘Újfehértói fürtös’ and Tandy 48' had the most attractive nectar for bees. There was no correlation between nectar composition and free fertilisation. On the basis of nectar composition the majority of the sour cherry cultivars studied can be classified into the sucrose-rich category; only one cultivar, 'Érdi jubileum' had a sucrose-dominant secretory product. The composition of nectar in the studied sour cherry cultivars is preferred by bees.
25-30.Vol 18No 12012
Concentration of Boron (B), Copper (Cu), Iron (Fe), Magnesium (Mg), Manganese (Mn) and Zinc (Zn) was analyzed in fresh and dried fruit samples of “Jumbo cot“, “Tom cot“, “Gold strike“, “Gold bar“, “Bergeron“, “Bergrouge“, “Sweet cot“, “Yellow cot“ and “Zebra“ apricot cultivars. Concentration of the studied eleme...nts was strongly affected by cultivars. B, Cu, Fe, Mn and Zn content of “Tom cot“ was significantly higher than other cultivars. “Gold strike“ had the highest amount of Mg. Similar tendency was observed in “Zebra“ and “Sweet cot“ where Mn content was significantly higher than the other element contents.
Preliminary evaluation of breeding perspectives of Ukrainian sweet cherry cultivars: nutraceutical properties and self-incompatibility
7-11.Vol 17No 1-22011
Some traditional sweet cherry cultivars of Ukrainian origin may represent perspective material for Hungarian cherry breeding. A total of eight cultivars analysed represent great diversity in several phenotypic traits including fruit ripening time or fruit flesh colour. Considerable differences in the anthocyanin content may result in different ant...ioxidant capacity of fruits. In the present study, we used ferric reducing antioxidant power (FRAP) and total phenolic content (TPC) assays to characterize fruits’ nutraceutical properties. These values were compared with the respective values measured for eight commercial cultivars grown in Hungary. The average of FRAP and TPC values was higher for the Ukrainian cherries compared with commercial cultivars suggesting they might be included in functional breeding programs. Since, cherry is a self-incompatible species, the determination of S-genotype is required for both breeding and successful cultivar association in commercial orchards. Complete or partial S-genotypes were determined for 5 and 3 cultivars, respectively.
41-44.Vol 16No 12010
Produce of harmonic nutrient balance and status of trees is basic task of growers for qualified fruit growing. The role of crop loaded is essential to grow the productivity of trees without nutrient disorder or other nutritional problems. To reduce the frequency of biennial bearing there are some ways (site and species selection, crop regulation, ...irrigation, nutrition etc.) from them one is the best easy way the proper site and species oriented nutrition. Sometimes the responsible for irregular cropping is the insufficient fertilization. Observed irregular cropping at two apple cultivars (Malus domestica Borkh., cv. ‘Summerred’ and cv. ‘Mutsu’) in an integrated apple orchard at Hajdúnánás-Tedej, in 2007 resulted a chance to determine nutritional status of “bearing” and “non bearing” trees and investigate the effects of irregular cropping on nutrient uptake and possibilities of correction. Our results pointed out that irregularity is connection on nutrition status of trees. Irregular cropping results in insufficient nutrient uptake and disharmony of nutrients. For this reason, the establishment of nutrient status of “non bearing” trees is could permit a chance to correct and improve the nutrient supply of trees which help to breakdown the vicious circle of irregularity.
Effect of frost damage on leaf macronutrient status of eight apple cultivars in integrated apple orchard in Eastern-Hungary
37-40.Vol 14No 1-2.2008
The year of 2007 was critical for fruit growers in the region of Easter-Hungary. Several orchards were suffered frost damages. Significant frost damage was also happened in the orchard of Tedej Rt., which caused total fruit failure in the orchard. Our study was conducted in the integrated apple orchard (Malus domestics Borkh.) established on a low...land chemozem soil in East-Hungary, to investigate how frost changes the mineral content of different apple species. Leaf samples were collected 100 days after full bloom both in 2006 and 2007. The concentrations of nitrogen, phosphorous, potassium, calcium and magnesium were measured in leaves. The absence of fruits caused a smaller accumulation of nitrogen and magnesium in leaves. Falling down of flowers and fruit sets hindered the translocation of the uptaken phosphorous, potassium and calcium towards fruit sets. Due to fruit failure the vegetative processes became dominant. Leaves larger amount of phosphorous, potassium and calcium stored. Besides the absolute element content, the ratio of the different elements was also determined. Majority of calculated ratios were removed from optimal values due to frost. Both absolute content of nutrients and their ratios pointed out that the frost damage significantly affected the uptake of nutrients and their storing processes.
The impact of location, row direction, plant density and rootstock on the sunburn damage of apple cultivars
19-30.Vol 11No 12005
The effect of row direction (N-S, E-W), plant density (conventional and intensive) and rootstock (M9, MM106 and crab apple) on the sensitivity of 41 apple cultivars to sunburn injury was studied at 6 locations (Derecske, Kálmánáaza, Nagykutas, Nagylapos, Siófok, Tornyospálca). During the observations the cultivars had rootstock-specific prop...erties in respect of sunburn-susceptibility. Accordingly, the injury was decreased in the order: M9, MM106 and seedling rootstocks. The differences in sensitivity depend on the canopy of trees, caused finally by the growing vigour of rootstocks. Accordingly, the highest value of sunburn injury was observed on M9 rootstock, because this rootstock has a dwarfing effect upon the scion cultivars. Thus, vegetative area of these trees grow very slowly and the foliage is not enough compact to protect the fruit from solar radiation. The size and density of the foliage increased in the order: M9, MM 106 and crab apple seedling as rootstock. Moreover, relationships were demonstrated between the diameter of upper part of the crown, the leaf area, the number of fruits per tree and the injury of sunburn. Authors categorized the cultivars in respect of values of sunburn incidence: 1. „Not sensitive", II. „Moderately sensitive" and HI. „Strongly sensitive" categories were constituted. Generally, Topaz and Gala cultivars showed low damage (or were free from symptoms), in contrast to this, Golden mutants suffered relatively much. The most sensitive cultivar was Jonica on all the three rootstocks. We searched for relationship between the fruit quality parameters and the frequency of sunburn. Significant correlation was found in the cases of fruit size and the extent of cover-colour. The latter is interpreted with the fact that the best coloured fruits are found on the periphery of crown as a consequence of more intense irradiation.
96-101.Vol 6No 12000
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.
Incidence of postharvest decays on cultivars of pear, apricot, sour cherry and peach under two storage conditions
63-65.Vol 17No 4-52011
In this two-year study, postharvest decays of pear, apricot, sour cherry and peach cultivars under two storage methods (TC and CA) were determined after four monthes storage periods; and then causal agents of postharvest decays of two pear cultvars were idenfified under traditional cold storage conditions. Results showed that postharvest decay was... lower under controlled atmosphere compared to traditional cold one. Decay was lower on pear and the largest deacy occured on peach and apricot cultivars. Cultivars of fruit species also showed differences in incidence of fruit decays. Incidence of decays was independent on year effect. Under controlled atmosphere, postharvest decay ranged between 0 an 8% for pear, and between 5 and 12% for apricot, and between 6 and 11% for sour cherry, and between 5 and 15% for peach. Under traditional cold storage, postharvest decay ranged between 16 an 21% for pear, and between 15 and 39% for apricot, and between 10 and 22% for sour cherry, and between 19 and 33% for peach. Incidence of pear fruit damage ranged between 7.5 and 12.3%. Most damage started from injured fruit or wounded fruit. Five types of damage occurred ont he pear fruits in both years: Penicillium spp., Monilinia spp., Chondrostereum spp., other pathogens and mechanical injury. The most common damage was caused by Penicillium spp., Monilina spp. and Chondrostereum spp. On both pear cultivars in both years.
17-22.Vol 13No 22007
Strawberry varieties were studied in 3 different growing areas of different soil- and ecological properties in Hungary. We have measured the optical spectra of the leaves together with their nutrient content and performed sensory examinations on the deep frozen and melted fruit. The 6 varieties were Elsanta, Marianna, Spadeka, Symphony, Camarosa, ...and Raurica. The 3 sites were Újfehértó, Pölöske, and Kecskemet. Colour of the leaves was characterised by their lightness and dominant wavelength. Under non-optimal soil and ecological conditions the varieties could be distinguished by their colour — the leaves became lighter and more yellow. The fruits did not produce the genetically determined taste if the plant can not grow in optimal circumstances — we found a negative correlation between the leaf colour in flowering time and the fruit flavour. Leaf colour measurements performed in flowering time make it possible to improve fruit quality by changing the nutrient supply between flowering and ripening.
61-64.Vol 7No 22001
Angel's trumpet (Danira = Brugmansia arhorea) is a common, popular ornamental plant in Hungary. On the basis of thin layer chromatographic and densitometric alkaloid studies of leaf and flower samples collected from several places in Somogy and Baranya counties it can be stated that in samples of cultivars with different flower colour, taken appro...ximately at the same time, the atropine and scopolamine content varies: there are samples free of alkaloids, but most of them are rich in alkaloids. Although the means do not reflect the extremes, they are suitable for determining the alkaloid accumulating capacity of flowers. Generally the amount of atropine and scopolamine is significant both in the leaf and the flower. It is conspicuous that the flower can be characterised by an extremely high scopolamine content (mean in mg/g dry matter of leaf: atropine 0.34, scopolamine 0.31; of flower: atropine 0.26, scopolamine 0.85). Thus it can be stated that the leaf, and especially the flower of angel's trumpet is a potential hallucinogen, just like in the case of Datura stramonium.
69-74.Vol 18No 12012
A greenhouse pot experiment was conducted to investigate the effects of ammonium-nitrate, food waste compost, bacterial fertilizer (EM-1) and their combinations on production and nutrient contents of carrot. The study was conducted on a calcareous chernozem and acidic sandy soils in a randomized complete block design with 8 treatments and four rep...lications. NH4NO3 in chernozem soil increased the weight of carrot leaves only, while in sandy soil resulted in reduced yield and highly increased NO3-N content of roots. Sandy soil showed higher response of biomass production to food waste compost application than chernozem soil. The highest carotenoid content of roots was measured with compost treatment. Combined application of compost and NH4NO3 in chernozem proved to be good combination but in sandy soil have turn out to be less favourable than sole compost treatment. Bacterial fertilizer (EM-1) did not cause marked effect on the yield parameters, but caused increased phosphorus content of plant. In chernozem soil the maximum yield parameters were achieved with the combined treatment of ammonium-nitrate+compost+EM-1. In sandy soil the most favourable treatment proved to be the compost treatment. Results suggest that application of food waste compost as a nutrient source could be a promising agrochemical practice especially in soils having low organic material and low nutrient supply.
39-44.Vol 17No 1-22011
Boron (B) is an essential micronutrient in plants especially in fruits. Despite of this fact there are very few information about its application, uptake and symptoms in Hungarian fruit growing sector. Nowadays we should consider the effects of weather conditions on soil B availability increasingly according to the climatic anomalies. Identifying ...of internal and external symptoms of plant parts (leaf, fruit) is help for growers to recognize the deficiency and excess symptoms in time. Methods and application rates of boron fertilization provide further information for growers to achieve qualify-oriented fruit growing among Hungarian conditions. The aim of this minireview is to focus on the importance of boron in fruit nutrition.
Test of the utility of apple retrotransposon insertion patterns for molecular identification of 'Jonathan' somatic mutants
7-10.Vol 14No 32008
Up until today, apple sport mutants proved to be indistinguishable from each other and their progenitors at the molecular level using random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) marker techniques. This is not surprising, since the genomes of these somatic mutants differ on...ly in one or a few small regions that affect economically important characteristics, such as improved fruit colour, size, or flavour. In most cases, these genome differences are probably caused by retrotransposons which are able to convert their RNA transcripts to DNA with reverse transcriptase enzyme prior to reinsertion, but unable to leave the genome and infect other cells. Retrotransposon insertions can alter the expression of other genes and/or the structure of encoded proteins. The sequence-specific amplified polymorphism (S-SAP) technique is capable of revealing the genetic distribution of retrotransposable elements over the whole genome. The present study used this approach to try to characterize and distinguish 'Jonathan' somatic mutants via fingerprinting, which is an unsolved problem.