Resolving the Parentage of the Apple Cultivar ‘Meran’

In the mid-1970s, a new apple variety named ‘Meran’ was discovered in South Tyrol (northern Italy), which harbours the largest continuous apple growing area in Europe. The cultivar was registered for varietal protection and patented in several countries, and was declared to be a cross of the varieties ‘Golden Delicious’ and ‘Morgenduft’ (synonym ‘Rome Beauty’). The parentage of ‘Meran’ has, however, been questioned, and the present study aimed to assess the descent of this cultivar by the combined use of molecular genetic and bioinformatic tools. Five accessions of ‘Meran’ were collected from three different European germplasm collections and analysed at 14 variable microsatellite DNA loci. Subsequently, computer software was used to allocate the most likely parent pair from a set of cultivars representative for the apple growing area of South Tyrol in 1975. The molecular genetic data clearly excluded ‘Morgenduft’ as a gene donor to ‘Meran’ and provided strong evidence that ‘Meran’ is a cross of the cultivars ‘Golden Delicious’ and ‘Jonathan’, confirming previous assumptions based on morphological traits of the tree and fruit.     

A greenhouse method for screening lettuce for resistance to Sclerotinia sclerotiorum

Agar blocks colonized by Sclerotinia sclerotiorum, causal agent of lettuce drop, were used as inoculum in screening for resistance to this pathogen in the greenhouse.Since the degree of resistance to the pathogen among cultivars varied with the time observed after inoculation, resistance was assessed by the number of days for 50% of the plants of each cultivar to die, as well as the number of plants that died. The cultivars ‘PI (Plant Introduction) 250427’, ‘Taiwan’, ‘PI 251790’, ‘PI 255568’, ‘MSU 73-44’ and ‘Bibb’ were found to have a higher level of resistance to S. sclerotiorum than the cultivar ‘Grand Rapids’ at 12 or 15 days following inoculation.     

Microsatellite markers based assessment of genetic diversity in Iranian olive (Olea europaea L.) collections

To study the genetic variation in Iranian olive collections and some foreign olive cultivars, 47 accessions of 18 local cultivars from 6 olive collections of Iran (Roudbar, Zanjan, Ahvaz, Dezful, Kazeroon and Shiraz), were analyzed along with 30 imported cultivars using 16 microsatellite primer pairs. All the used microsatellite loci revealed polymorphism in the studied genotypes, except GAPU14 and GAPU113 markers. Fourteen microsatellite primers amplified 126 polymorphic alleles in the 87 selected olive accessions. The average number of alleles per locus was 9, ranging from 3 to 14. Polymorphic information content (PIC) was 0.85. The genetic similarity based on Jaccard coefficient ranged from 0.15 to 1. The genetic relationships among accessions were investigated using cluster analysis and principal component analysis (PCA). Most of the accessions with the same name were grouped together; some exceptions were also observed. As expected, close relationship was observed among accessions within same cultivar. Most of the Iranian olive accessions were clustered to a main distinct group. Two-dimensional scatter plot of principal component analysis revealed a clear separation of most of the Iranian olives from Syrian and other introduced cultivars. These suggest that Iranian cultivars have different origin related to West Mediterranean basin cultivars and have evolved independently from the others. Between and within Iranian and foreign cultivars (cultivars including three or more accessions) genetic diversity was analyzed using analysis of molecular variance (AMOVA). AMOVA revealed higher within cultivar genetic variation (62.76%) as compare to that between cultivar variations (37.24%). The intra- and inter-cultivar variance tested by permutation test showed significant genetic variation at both levels. The high level within cultivar genetic variance could be due to mislabeling and presence of homonyms in cultivars produced by vegetative propagation from original plants.     

Cultivars Resulting From Cherry Breeding in Germany

In Germany the sweet and sour cherry breeding is concentrated at the Julius Kühn-Institut in Dresden-Pillnitz. The main breeding goals are directed on sweet cherries for fresh market and sour cherries for processing. The selection of new cultivars is focused on fruit quality, high and stable fruit set and tolerance to biotic and abiotic stress. In result of the breeding activities in sweet cherry four new cultivars, ‘Narana’, ‘Areko’, ‘Swing’, ‘Habunt’, were selected. ‘Narana’ is an early ripening cultivar with good fruit characteristics. ‘Areko’ ripens in the middle of the cherry season some days before cultivar ‘Kordia’ and has large, firm fruits. The both cultivars ‘Swing’ and ‘Habunt’ are self-compatible and more recommended for the use in house gardening. In sour cherry breeding four new cultivars, ‘Coralin’, ‘Spinell’, ‘Jachim’, ‘Boas’, were selected. The cultivar ‘Coralin’ shows good characteristics for processing and mechanical harvest and is tolerant to fungus diseases on leaves. With the large and tasty fruits, the cultivar ‘Spinell’ is mainly suitable for fresh consumption. The both other cultivars ‘Jachim’ and ‘Boas’ have a pillar growth habit.     

Somaclonal variation with early juice-sac granulation obtained by inter-specific protoplast fusion in citrus

Summary

Six plants with an early juice–sac granulation trait derived from inter-specific protoplast fusions between embryogenic calli of ‘Bonanza’ navel orange (Citrus sinensis [L.] Osbeck) and mesophyll protoplasts of ‘Dahongpao Red’ tangerine (C. reticulata Blanco) were analysed by flow cytometry and by using molecular markers, including simple sequence repeats (SSR) and restriction fragment length polymorphism (RFLP). The results indicated that all six plants were diploids and had inherited their nuclear DNA from the embryogenic callus parent ‘Bonanza’ navel orange. However, an analysis of morphological and fruit characteristics, and measurements of components of the cell walls in the juice-sacs, showed that they were not true-to-type for ‘Bonanza’ navel orange, especially for fruit traits such as juice-sac granulation and navel structure. These results confirmed that these plants were not hybrids, and were more likely to be somaclonal variants that arose during the regeneration of the navel orange protoplasts. These plants will provide material for studying the mechanism of granulation in juice-sacs, a common phenomenon during the storage of pummelo and other citrus fruits.     

Agronomic and nutritional quality,and fresh and processing attitude,of globe artichoke (Cynara cardunculus L. var. scolymus) cultivars and an Italian landrace

Globe artichoke (Cynara cardunculus L. var. scolymus) plants of a typical landrace (‘Montelupone A’) from the Marche region (Italy) and three commercial cultivars (‘Apollo’, ‘Romanesco C3’, ‘Exploter’) were compared as a detailed analysis of their productive, morphological, qualitative, and nutritional parameters was carried out to characterise their particularities and suitability for the fresh market or the processing industry. Cultivar ‘Apollo’ stands out for its qualitative and agronomic aspects, with ‘Romanesco C3’ showing high flower head yield, as the most important Romanesco cultivar that is widely cultivated in central Italy. ‘Exploter’ shows high productivity and qualitative characteristics. The lower phenol content of ‘Exploter’ indicates its suitability for processing as a fresh cut preparation. The ‘Montelupone A’ landrace is characterised by beneficial nutritional values that indicate its use for fresh consumption and as a source of antioxidant compounds. The ‘Apollo’ and ‘Romanesco C3’ commercial cultivars show higher processing yield due to flower head characteristics. In particular, ‘Apollo’ has an interesting profile according to its technological qualitative and nutritional value. ‘Exploter’ differs in its high yield and suitability for the fresh market. Analysis of the ‘Montelupone A’ landrace confirms its interesting qualitative and nutritional values.     

Einfluss von blattappliziertem Bor auf Boraufnahme und Fruchteigenschaften von Kulturheidelbeeren (Vaccinium corymbosum)

In 2003, highbush blueberry (Vaccinium corymbosum) cultivars ‘Brigitta Blue’ and ‘Nelson’ were treated with a foliar boron-containing, ascofol spray (Wuxal^®). After blossoming, the plants were sprayed three times with 0.5% ascofol solution. Control plants were sprayed with tap water. Fruit harvest of each cultivar was on July 19 and 30, respectively. Leaf samples were taken on June 4 and August 7. The boron content of fruits and leaves was analyzed along with fruit yield and single berry weight. The potential absorption rate of applied boron (boron increase in leaves and fruits) was calculated. Foliarly applied boron was readily taken up by the leaves of both cultivars and translocated to the fruits. A potential boron absorption rate of 2.4% was calculated for ‘Nelson’. Foliar application of boron did not increase fruit yield in either cultivar. However, ‘Nelson’ showed a slight increase of berry weight in the second harvest, associated with the boron treatments.     

A hypothesis to explain the relationship between low-temperature treatment,gibberellin activity,curd initiation and maturity of cauliflower

The effects of cold-treating young cauliflower plants (Brassica oleracea var. botrytis L.) of the cultivars ‘Lero’, ‘Lawyna’, ‘Novo’ and ‘Janavon’, on gibberellin activity and the spreads of curd initiation and maturity are described and discussed in relation to other similar work.Exposure of plants to 0°C for 15 days increased gibberellin activity in the apices of ‘Lero’ and ‘Lawyna’ plants. The spreads of curd initiation and maturity of ‘Lawyna’ were significantly reduced by cold-treatment at 0°C, but ‘Lero’ was not affected, possibly because plants had initiated too many leaves and were thus beyond the stage receptive to low-temperature treatment. This treatment had no effect on gibberellin activity nor on the spreads of curd initiation and maturity of ‘Novo’ or ‘Janavon’, probably because plants had not reached the sensitive stage when cold-treated.It is postulated that the phase of growth during which the curd-initiation period can be shortened by cold treatment is specific for each cultivar, and other data were used to confirm this. It seems likely that the receptive phase occurs at higher leaf-numbers with cultivars which take longer to initiate curds.     

Controlling the growth and development of rose plants after planting

The effects of pinching and lateral bud removal (deshooting) on the development of structural shoots, the number of flowers, and the average flower stem length in young rose plants were examined, using the cultivars ‘Baccara’, ‘Sonia’ and ‘Belinda’. The effect of deshooting on flower yield varied with each cultivar. It did not affect the number of ‘Baccara’ flowers, but increased ‘Sonia’ and ‘Belinda’ flower production by 50% and 75%, respectively. Leaving flowers to bloom out on plants before the start of commercial harvest resulted in a decrease in the length of the flower stems and also reduced the beneficial effect of deshooting on flower yield. Deshooting enhanced structural shoot formation (“bottom breaks”). Pinching flower buds of structural shoots increased the number of ‘Baccara’ flowers in comparison with pruning these shoots to 40–60 cm, as in common practice. Deshooting of the structural shoots of ‘Sonia’ and ‘Belinda’ increased the number of flowers in both cultivars.     

Peroxidase isoenzyme genes in the identification of apple cultivars and Malus species

The peroxidase genotypes of 188 apple cultivars, rootstocks and Malus species were recorded. Four loci, PRX-2, PRX-3, PRX-4 and PRX-7 were involved including 15 alleles. Using this information a clear grouping of 83 cultivars, 46 rootstocks and 59 species was achieved through knowledge of the genetic basic of banding patterns, which consequently enabled secondary and inconsistent bands to be recognised and disregarded as relevant factors in identification. The possible selective advantage of the PRX-2e allele recognised in descendants of ‘Jonathan’ (PRX-2ce) is discussed. Triploid cultivars showed three different PRX-2 alleles including ‘Ashmead’s Kernel’ (PRX-2bce), providing further evidence of the triploid nature of this cultivar.     

Splitting Severity Among Rabbiteye (Vaccinium ashei Reade) Blueberry Cultivars in Mississippi and Louisiana

Abstract

A survey of blueberry growers determined the extent of rain-related splitting fruit on blueberry production in Mississippi and Louisiana. Growers were asked to approximate (1) the number of acres or plants of each cultivar on their farm (2) the severity rating (1 = No splitting-5 = Severe splitting) of each cultivar, and (3) the percent of berries lost to rain-related splitting. Among the 3 most widely planted cultivars, ‘Premier’ exhibited the least splitting (1.2 rating) followed by ‘Climax’ (2.2) and ‘Tifblue’ (3.1) had the most split fruit.     

Cross-(in)compatibility in apricot (Prunus armeniaca L.)

Summary

Eight apricot (Prunus armeniaca L.) cultivars and selections were self- and cross-pollinated in order to determine their pollen and stylar compatibility. Overall, 40 pollination combinations were examined. Pollen-tube growth in pistils pollinated in the laboratory was analysed using fluorescence microscopy. Three inter-incompatiblity groups of cultivars were found, of which two had not been described previously, while an existing group was expanded with one additional cultivar. The first group consisted of three Hungarian cultivars (‘Ligeti Orias’, ‘Cegledi Orias’, and ‘Szegedi Mammut’) and a Moldavian cultivar (‘Kostjuzhenskyi’). The second group consisted of two American cultivars (‘Stark Early Orange’ and ‘Nugget’). The third group consisted of two Serbian selections (‘Novi Sad Early’ and ‘Frushka Gora Early’). In the incompatible cultivar combinations, pollen-tube growth stopped in the style with the formation of the characteristic swelling. In the compatible combinations, the pollen tubes reached the ovary in the majority of the pistils examined.     

A 3-Year Adaptation Study of Three Distinct Grapevine Cultivars under Midwestern Field Conditions

Simultaneous responses of American (Concord), European (Pinot Noir), and American-European hybrid (Traminette) cultivars to seasonal and diurnal variation in field environmental conditions were assessed to propose suitable cultivars for potential use for selection and breeding in grapevines in dry areas. ‘Pinot Noir’ had higher gas exchange parameters, higher water potential, and chlorophyll fluorescence, while ‘Concord’ had the lowest values in all three seasons and experienced moderate stress by the end of each season. The dry conditions in 2005 caused water potential to decline sharply compared to values recorded in 2004 and 2006. ‘Pinot Noir’ and ‘Traminette’ exhibited a mild stress, while ‘Concord’ exhibited a moderate stress in 2006. Photosynthetic rate decreased slightly during the summer with a slight recovery at the beginning of September, and did not differ across the seasons among cultivars. Stomatal conductance followed the same pattern. However, in both 2004 and 2005, stomatal conductance dropped sharply late in the season because of frequently occurring high temperatures that were greater than 32 °C. Maximum morning values of Fv/Fm were within the optimal range. The study suggests the presence of marginal photoinhibition during mid-summer in Concord cultivars, because no full recovery of photochemical efficiency early in the evening was observed. The European cultivar (Pinot Noir) and the American-European hybrid (Traminette) are more adapted to field conditions in Kansas than Concord cultivars. However, high cold-mortality of Pinot Noir due to high sensitivity to cold winter temperature makes the hybrid cultivars the most suitable cultivar for Midwest regions with relatively cold winters.     

Highbush Blueberry Cultivar Trial in Ontario,Canada

ABSTRACT

A replicated trial of eleven cultivars was planted at Simcoe, Ontario in 1991. Plants were first harvested in 1994. After eight harvest seasons, ‘Bluegold’ was the highest yielding cultivar, averaging 6.8 t/ha, and ‘Toro’ had the largest berries, averaging 1.81 g per berry. ‘Bluetta’ was the earliest cultivar with on average 50% of its yield picked by 16 July and ‘Elliott’ the latest, with on average 50% of its yield picked by 27 August. Overall, ‘Duke’ proved to have the best combination of characteristics of the early cultivars, and ‘Nelson’ was the most impressive late cultivar.     

5个矮生牡丹品种黄化嫩枝扦插技术研究

 研究了牡丹矮生品种‘银粉金鳞’、‘蓝田玉’、‘金玉交章’、‘小胡红’和‘石原白’黄化嫩枝扦插繁殖的关键环节和影响因素。结果表明, 该5 个品种黄化嫩枝生根率依次为91.0%、80.9%、78.6%、40.6%、20.0%; 于10月中旬截取长4～6 cm、基部直径0.5 cm以上的黄化嫩枝, 将形态学下端浸泡在20～25℃的IBA 100 mg/L或‘ABT 2号’150 mg/L中16 h, 扦插于粒径3～4 mm的蛭石基质里,‘银粉金鳞’插穗的生根率最高, 达93% , 且不定根健壮、上盆栽培生长良好。     

Microsatellite marker-based identification of mother plants for the reliable propagation of olive (Olea europaea L.) cultivars in Australia

Summary

Olive production in Australia has continued to increase in recent years, however there remains a high degree of confusion on the genetic identities of the cultivars being grown. In the present study, seven microsatellite (simple sequence repeat; SSR) loci were used to identify a set of 53 olive tree samples from different sources. The microsatellite DNA profiles of all 53 tree samples, including seven unknown trees, were compared with the SSR profiles of 14 reference olive cultivars. A total of 60 fragments (alleles), averaging 8.57 alleles per microsatellite locus, were amplified. High average values were found for the observed heterozygosity, the expected heterozygosity, and the polymorphic information content (0.73, 0.74, and 0.72, respectively). While all seven microsatellite markers proved useful for characterisation and identification purposes, a combination of three SSR primer pairs (DCA9, DCA18, and EM030) was sufficient to distinguish all 53 olive samples. The microsatellite allelic profiles allowed the 53 tree samples to be grouped into 23 genotypes. The allelic profiles of 14 of these genotypes matched with their reference cultivars, while the genetic identities of the remaining nine genotypes could not be confirmed. Some of these unknown genotypes may have been derived from feral olive trees, or were due to mislabelling and/or planting errors among Australian olive cultivars. Our results confirm the usefulness of microsatellite markers as a tool for cultivar differentiation and identification, and indicate the need for reliable identification of mother plants for commercial propagation.     

Physiological and anatomical responses of calendula (Calendula officinalis L.) cultivars to heat-stress duration

It is necessary to identify the heat-tolerant cultivars of bedding plants in order to cope with the challenges of the global warming. The physiological and anatomical responses of four calendula cultivars (Candyman’, ‘Zen’, ‘Indian Prince’, and ‘Pacific Beauty’) to four duration levels (0, 7, 14 and 21 days) of heat stress (in a mean range of 35–42°C), were investigated after their establishment under greenhouse conditions. The results indicated that calendula cultivars displayed different responses to various heat duration levels in most parameters. Although the gas exchange of ‘Candyman’ was the highest in control treatment, it showed a considerable reduction in all levels of stress durations. In contrast, ‘Indian Prince’ maintained gas exchange and chlorophyll content and exhibited the most resistance to heat stress among others, especially for longer duration exposure, which might be resulted from the greater soluble sugar content, higher stomatal density, and thicker leaves. Experiment to assess cell membrane thermostability showed heat stress resulted in significant increase in electrolyte leakage percentage as the incubation temperature of all cultivars was increased. However, the least membrane stability was observed in ‘Zen’, indicating the higher sensitivity of this cultivar to heat-stress conditions in comparison to three other cultivars.