Autumn Bliss Research Articles

Chromosome-scale genome sequence assemblies of the 'Autumn Bliss' and 'Malling Jewel' cultivars of the highly heterozygous red raspberry (Rubus idaeus L.) derived from long-read Oxford Nanopore sequence data.

Red raspberry (Rubus idaeus L.) is an economically valuable soft-fruit species with a relatively small (~300 Mb) but highly heterozygous diploid (2n = 2x = 14) genome. Chromosome-scale genome sequences are a vital tool in unravelling the genetic complexity controlling traits of interest in crop plants such as red raspberry, as well as for functional genomics, evolutionary studies, and pan-genomics diversity studies. In this study, we developed genome sequences of a primocane fruiting variety ('Autumn Bliss') and a floricane variety ('Malling Jewel'). The use of long-read Oxford Nanopore Technologies sequencing data yielded long read lengths that permitted well resolved genome sequences for the two cultivars to be assembled. The de novo assemblies of 'Malling Jewel' and 'Autumn Bliss' contained 79 and 136 contigs respectively, and 263.0 Mb of the 'Autumn Bliss' and 265.5 Mb of the 'Malling Jewel' assembly could be anchored unambiguously to a previously published red raspberry genome sequence of the cultivar 'Anitra'. Single copy ortholog analysis (BUSCO) revealed high levels of completeness in both genomes sequenced, with 97.4% of sequences identified in 'Autumn Bliss' and 97.7% in 'Malling Jewel'. The density of repetitive sequence contained in the 'Autumn Bliss' and 'Malling Jewel' assemblies was significantly higher than in the previously published assembly and centromeric and telomeric regions were identified in both assemblies. A total of 42,823 protein coding regions were identified in the 'Autumn Bliss' assembly, whilst 43,027 were identified in the 'Malling Jewel' assembly. These chromosome-scale genome sequences represent an excellent genomics resource for red raspberry, particularly around the highly repetitive centromeric and telomeric regions of the genome that are less complete in the previously published 'Anitra' genome sequence.

Investigating Biochemical and Histopathological Responses between Raspberries and Aculeastrum americanum

Late leaf rust is a fungal disease in raspberries caused by Aculeastrum americanum (Farl.) M. Scholler U. Braun (syn. Thekopsora americana (Farl.) Aime McTaggart) leading to early defoliation and yield losses. Red raspberries (Rubus idaeus L.) are susceptible to this pathogen, although this susceptibility varies among cultivars. In contrast, black raspberries were previously reported to be more resistant (Rubus occidentalis L.) and immune (Rubus niveus Thunb.) to this pathogen, raising their importance in plant breeding programs. However, what features make them respond differently to the same pathogen? In this study, we characterize for the first time the pre- and post-formed structural and biochemical defense mechanisms of R. idaeus cv. Autumn Bliss, R. occidentalis and R. niveus. Ultrastructural and histopathological analyses were used to uncover the interactions between these raspberries and A. americanum. The ultrastructural results indicate that the pathogen germinates on both leaf surfaces but can only form appressoria on the stomata. Although the three raspberry species were infected and colonized by A. americanum, a clear difference in susceptibility was observed between them. A compact mesophyll, pre- and post-formed phenolic compounds, and post-formed pectic compounds were the main plant defense mechanisms against fungal colonization. These findings provide new information about raspberries' defense mechanisms in response to A. americanum and elucidate the interactions occurring in these pathosystems.

The Main Morphological Characteristics and Chemical Components of Fruits and the Possibilities of Their Improvement in Raspberry Breeding

Raspberry is a delicious fruit with important nutritional and health properties for consumers. The efficiency of achieving raspberry breeding aims such as productivity, fruit quality, and adequate response to stressors, etc., depends directly on knowledge of the inheritance of traits and genetic factors of influence and their pragmatic use. In this study, the main morphological characteristics and chemical components of fruits of 24 raspberry genotypes were studied in a comparative field trial; 14 were promising selections and the other 10 included their parental forms (Autumn Bliss, Glen Moy, Glen Prosen, Opal, Pathfinder, Titan, Tulameen, Veten, Willamette) and Glen Ample cultivar, which was used as control. The results highlighted significant differences and a large variation among the genotypes (between 2.40 and 4.90 g for fruit weight, 0.19–0.47 kg/cane for yield, 50–106 for drupelets/fruit, 10.0–12.7% for dry matter, 0.23–2.00% pectin, 1.61–2.72% glucose, etc.). The inheritance of the analyzed traits, considered quantitative, was different, but a low heritability was recorded for non-marketable fruits and the number of drupelets in fruit. In several hybrid selections, negative heterosis prevailed, highlighting the breeding difficulties of the important desired traits of the species. The values of heterosis and the broad-sense and narrow-sense heritability of some traits demonstrate that, through judiciously choosing parents, raspberry breeding in the desired direction can be successful.

Integrative analysis of high temperature-induced transcriptome and metabolome alterations in the leaves of five raspberry (Rubus ideaus L.) cultivars

Raspberry has been widely accepted as a healthy fruit, but its planting in northwest China is restricted due to its heat sensitivity. To make the best use of raspberry and compare the potential for their cultivation in northwest China, five important raspberry cultivars ('Autumn Britten', 'Autumn Bliss', 'Red Autumn', 'Korean Black', 'Heritage') were collected and evaluated for their responses under high temperature stress (HTS, 32.8 ℃, compared to ambient temperature 20.4 ℃). The transcriptome and metabolome profiles are dramatically affected and show different response patterns of different cultivars to HTS. While ‘Korean Black’ and ‘Hertitage’ exhibited distinctive responses to HTS when comparing transcriptome and metabolome profiles. After enrichment analysis, we found that HTS mainly affected the amino acids and saccharide metabolism, accumulation of antioxidant metabolites and plant hormone-related MAPK signaling pathways, and alteration of α-linolenic acid metabolism in all five cultivars. Transcription factors were also analyzed and HSF (Heat Shock Transcription Factor) was identified as promising regulatory candidate for heat stress responsive gene expression in raspberry cultivars. Integrative analysis shows that the α-linolenic acid metabolism pathway is greatly altered in ‘Korean Black’ at both metabolite accumulation and gene expression levels under HTS. Especially for linolenic acid 13(S)-HPOT and jasmonic acid, as well as for genes such as PLA2-ALPHA（Ro04-snap-gene-272.47）, DAD1（Ro02-snap-gene-93.71）, LOX3（Ro03-snap-gene-410.98）, JMT（Ro04-snap-gene-23.45) are critical in HTS responses when comparing ‘Hertitage’ and ‘Korean Black’. Our work provides potential metabolic mechanisms for raspberry stress responses and suggests master genes and transcription factors responsible for stress resistance as potential targets for molecular breeding. • Five important raspberry cultivars were collected and evaluated for their responses under high temperature stress. • There are different response patterns of different cultivars to HTS. • The α-linolenic acid metabolism pathway is greatly altered under HTS.

Comparative Study of Three Raspberry Cultivar (Rubus idaeus L.) Leaves Metabolites: Metabolome Profiling and Antioxidant Activities

Raspberry (Rubus idaeus L.), known as one of the famous healthy fruits an d are consumed fresh or processed products all over the world. The antioxidation activity of raspberry fruits as well as leaves have been widely investigated. To better understand the metabolite accumulation mechanisms and to develop different functional cultivars, we performed a non-targeted metabolomics analysis using LC-MS/MS to investigate the contents of existing components from three raspberry cultivars, Autumn Britten, Autumn Bliss, and Red Autumn leaves, respectively. The results show multiple differentially accumulated metabolites among three cultivars, especially for the lipids (α-linolenic acid and eicosatetraenoic acid), amino acids and their derivatives (L-cysteine, Phenylalanine), flavonoids (Kaempferol 3-O-rhamnoside-7-O-glucoside, Quercetin 3-glucoside), and vitamins (Biotin, Thiamine, Vitamin K2), etc. The in vitro cellular antioxidant activities of three raspberry cultivars leaves ethanol extracts (RLEE) were also characterized. Through comparison the superoxide dismutase (SOD), glutathione (GSH), catalase (CAT), and reactive oxygen species (ROS) levels before or after RLEE protection of L929 fibroblast cells upon excessive UVB exposure, we evaluated the antioxidation potentials for all three cultivar RLEEs. It turns out the raspberry Autumn Britten leaf extract holds the greatest potential for protecting the L929 fibroblast cells from UVB induced damage. Our study provides theoretical support for screening of active metabolites from three raspberry cultivars leaves, spanning metabolites’ accumulation to cell damage protection, which could be used to refine bioactivity assessment for different raspberry cultivars suitable for antioxidant products extraction.

Floricane yield and berry quality of seven primocane red raspberry (Rubus idaeus L.) cultivars

Primocane raspberry (Rubus idaeus L.) may produce crop on the lower part of the cane during the second year of its’ growth cycle, if the canes are retained over winter. We aimed to evaluate the floricane cropping potential and berry quality in seven primocane raspberry cultivars, which are too late for fall cropping in the Northern growing conditions. Long cane plants of these cultivars were produced, overwintered, and grown like floricane cultivars in a high tunnel. Harvesting floricane crop started in mid-June, and the length of the summer cropping season was between eight to 10 weeks. 'Joan J' and 'Imara' were the earliest cultivars, and 'Autumn Bliss' was the latest. Total floricane yield in most cultivars was between 1.7 to 2.0 kg/cane. ‘Autumn Treasure’ yielded significantly less, and ‘Autumn Bliss’ produced 2.5 kg berries /cane. The average berry size was 5 g, except in ‘Autumn Bliss’ and ‘Autumn Treasure’, which had smaller berries. The highest sugar content was observed in 'Kwanza' berries and the lowest in 'Polka'. High throughput phenotyping proved an effective tool for determining berry shape and color. ‘Kwanza’ berry color was the reddest, yellowest and lightest of all cultivars. Based on our results, growing primocane raspberry cultivars as long cane plants for production of summer crop is more reliable than growing them as fall cropping in short growing season conditions. The cultivars ‘Imara’ and ‘Kweli’ were the most promising in our experiment; they had a high yield potential and excellent berry quality.

A Comparison of Nine Primocane Fruiting Raspberry Cultivars for Suitability to a High-Elevation, Arid Climate

ABSTRACT A replicated trial, planted in 2011, compared nine primocane-fruiting raspberry cultivars for suitability to commercial production in the U.S. Intermountain West. Factors evaluated included annual yield, fruit size, fruiting season, consumer preference, leaf chlorophyll content, and cane infestation by raspberry horntail, a common insect pest of raspberries in northern Utah. ‘Joan J’ was the highest yielding cultivar, averaging 3.32 kg per row meter, followed by ‘Polana’, ‘Autumn Bliss’, and ‘Dinkum’ with 2.53, 2.01, and 1.34 kg·m−1, respectively. ‘Autumn Bliss’ and ‘Joan J’ were the earliest to fruit with a harvest midpoint 4 and 2 days before ‘Polana’, respectively. Leaf chlorophyll concentration (CCl) was highest in ‘Joan J’ and ‘Autumn Treasure’, averaging 30.9 and 27.0 CCl, respectively. All cultivars exhibited similar susceptibility to raspberry horntail, with differences in infestation rates related to the location in the field. A survey of farmers’ market customers found the highest consumer preference for ‘Autumn Bliss’, ‘Dinkum’, and ‘Vintage’. Only the earliest cultivars gave commercially viable yields for the high elevation valleys of the Intermountain West region of the U.S.

Quality, bioactive compounds and antioxidant capacity of raspberries cultivated in northern Mexico

ABSTRACT This study aimed to characterize the quality and bioactive compounds from five cultivars grown in Mexico´s northern region: Heritage, Summit, Harvest, and red and yellow Autumn. The physicochemical characteristics, DPPH anti-radical capacity, total phenolics, flavonoid and anthocyanins, polyphenolic profile, and ascorbic acid levels of the raspberries were assessed. The Harvest cultivar presented the highest weight and firmness and the lowest yield, total phenolics, and flavonoids. The yellow Autumn Bliss contained higher concentrations of polyphenols and ascorbic acid, and the red Autumn Bliss contained higher concentrations of flavonoids and anthocyanins and possessed a greater antioxidant capacity. The polyphenol profile indicated the presence of seven phenolic acids, namely, ellagic, gallic, caffeic, chlorogenic, p-coumaric, hydroxybenzoic, and protocatechuic acids; and four flavonoids, namely, catechin, quercetin-3-β-D-glucoside, quercetin-3-glucuronide, and rutin; these compounds were present in all the varieties, except for rutin, in yellow Autumn Bliss. The results of this study highlight the most valuable raspberry cultivars in terms of weight and firmness (Harvest), yield (Heritage), polyphenols and ascorbic acid (yellow Autumn Bliss), and anthocyanins and antioxidant capacity (red Autumn Bliss) in raspberries grown in northern Mexico.

Raspberry production with different NPK dosages in South Brazil

The present work aimed to evaluate the raspberry production with different dosages of the macronutrients N, P, and K in the region of South Brazil. The experiment was implanted in the Serra Gaúcha region, South Brazil (Köppen classification Cfb). The raspberry variety ‘Autumn Bliss’ as evaluated, planted with spacing of 2.0 m between lines and 0.3 m between plants, irrigated by dripping. The experimental design was of randomized blocks, constituted by 7 treatments and 4 repetitions. The macronutrient dosages ranged between 0 and 300 kg/ha for N, and from 100 to 200 kg/ha for P and K. The evaluated parameters were fruit yield, soluble solids content, titratable acidity, and ratio value. The nutrient content in soil and leaves were also evaluated. The data underwent analysis of variance and the means were compared by Tukey’s range test at 5% probability. It was observed an increase in fruit yield until N dose of 200 kg/ha. There was no difference among the treatments that ranged P and K doses. The fruit quality parameters have not presented statistical difference among treatments. It was concluded that raspberry responded well to nitrogen fertilization and smaller doses of P and K supplied the plant’s needs.

Raspberries and gooseberries in south Patagonia: Production, fruit quality, morphology and phenology in two environmental conditions

Fine fruits as raspberry and gooseberries represent the second production with the largest area cultivated in Santa Cruz province (Argentina), and this activity is usually carried out by family farmers in outdoor conditions. The availability of information about productive, morphologic, phenological and quality aspects of these crops in south Patagonia is very scarce. The aim of this work was to evaluate performance of Rubus idaeus cv. Autumn Bliss (RIA), R. idaeus cv. Glean ample (RIG), Ribes rubrum (RR), Ribes nigrum (RN) and Ribes uva crispa (RU) under two environments: outdoors and in greenhouse. An essay with a split plot design, with environment as the main plot and the species as a subplot, with three replicates, was established. Variables related to morphology, phenology, fruit production and fruit quality were measured. Significant differences were found in fruit production according to environment. At the third year, fruit production in greenhouse was 19.6, 130.7, 626.2, 693.1 and 1308.7 g plant−1 for RIG, RR, RN, RIA and RU, respectively. In the same year, production outdoors was 14.3, 80.5, 84.6, 90.7, 343.1 RIG, RN, RR, RIA and RU, respectively. Environment also affected individual fruit weight, being 1.79 g the mean fruit weight in greenhouse and 0.98 outdoors. Morphologic variables had a strong influence on fruit production, mainly on node number and foliar area. Results showed a 65% higher mean production efficiency of plants (gr fruits/m2 foliar area) in greenhouse compared with outdoor plants. In general, raspberries in outdoor condition decreased 90% in production efficiency, whereas gooseberries decreased 40%. In average, RIA were the most efficient plants throughout all the study period and RU had the highest efficiency during the last year of production. In conclusion, outdoor production of these species in South Patagonia is not recommended, because temperature and wind intensity severely affected plant performance. However, if outdoor condition is the only option, cultivate RU is the best option.

Effect of low temperature in the first development stage for five red raspberry genotypes

In raspberry, the expression of the primocane fruiting trait is influenced by the environment. Although there are several factors that influence the expression of this character, it is well known that low temperatures that occur during the growth season of the primocane, are important and affect the flowering. In this study, plants in their early stages of development were exposed to low temperatures (2°C) for one month, in a dark cold chamber. The following genotypes primocane and floricane were used: ‘UC103’, ‘Autumn Bliss’, ‘Heritage’, ‘Meeker’ and ‘Tulameen’. Flowering and growth were recorded until the end of the season and the morphology of the meristem was characterized in this moment. Interaction between cold and genotype was detected in all parameters studied. In ‘Heritage’, a slight primocane, growth and flowering were favoured by exposure to cold. Thereby, low temperature affects flowering, but this effect depends on primocane fruiting degree of each genotype, slight primocane the cold favored flowering and growth. However, strongly primocane the cold had no effect on flowering and growth.

Лучшие генетические источники и доноры технологических свойств в селекции ремонтантной малины

The results of breeding evaluation of the genetic collection (over 40 varieties and 150 selected forms) and the hybrid fund of primocane raspberry (more than 15 thousand seedlings) of the Kokino Base Station of FSBSI ARHIBAN are presented. The best donors and sources of a bush compactness (varieties Evrasia, Pingvin, Autumn Bliss, 1-16-11, 3-238-10, 44-154-2, 3-09-1), thornless of shoots (Joan J, Joan Squire, Motueka, Himbo Top, 13-118-1, 9-155-1, 9-77-10), strength of fruits (Atlant, Brusvyana, Zhar-ptitsa, Evrasia, Pingvin, Karamelka, Samorodok, Kwanza, Heritage) and their long storage after harvesting have been revealed (Atlant, Evrasia, Karamelka, Driscoll`s Maravilla, Heritage, Polka, Kwanza).

Nutrient Uptake and Utilization and Antioxidants of Fruits in Red Raspberry (Rubus idaeus L.) Cultivar ‘Autumn Bliss’ in response to Fertilization under Extended Photoperiod

Annual-fruiting cultivars of red raspberry (Rubus idaeus L.) complete its entire cycle of vegetative growth, flowering, and fruiting in one growing season, which has not been well studied in response to treatments of photoperiod and fertilization. In this study, micro-propagated plantlets of ‘Autumn Bliss’ were planted in a greenhouse at Dalian, Northeast China. Some were treated with fertilizers at the rate of 12 g per plant (N-P2O5-K2O, 14-14-14) under extended photoperiod of 17 h with PPFD of 240 μmol m-2 s-1 at dark-time (Pho.+Fert.), while others were treated with longer photoperiod (Pho.) or with the control. Compared to the control, both growth and biomass in shoot part of ‘Autumn Bliss’ were promoted by the Pho.+Fert. treatment, but foliar nutrients declined as the symptom of nutrient dilution. The Pho. treatment had no effect on either growth or nutrient uptake in leaves, resulting in the symptom of nutrient depletion compared to the Control. Soil P availability positively correlated with foliar P concentration but negatively correlated with root length. Only the Pho.+Fert. treatment resulted in the advance of fruiting by two months at July when fruits were measured to have acceptable fruit weight of about 3 g and contents of anthocyanin at ~26.4 mg cyaniding-3-glucoside equiv. 100 g-1 Fw and total phenolic content at ~17.5 mg GAE 100 g-1 Fw.

GENETIC IDENTITY OF RASPBERRY ‘POLANA’ PLANTLINGS EXAMINED USING MICROSATELLITE MARKERS

Raspberry cultivars are clonally propagated and therefore all plants belonging to a single cultivar represent the same genotype. Cultivar integrity of raspberry plantlings placed on the market in Bosnia and Herzegovina (B&H) is based on examining of morphological traits, which is not a reliable tool for genetic identification. In this study plantlings declared as cultivar ‘Polana’ were genotyped using seven microsatellites, in order to gain preliminary insight into the genetic integrity of raspberry plantlings marketed in B&H. Plant tissue (leaves) from 10 raspberry plants were randomly sampled from a batch of plantlings sold by major fruit nursery in Bosnia and Herzegovina. Along with these samples, four reference cultivars with confirmed identity (‘Polka’, ‘Autumn Bliss’, ‘Heritage’ and ‘Polana’) were also included in the study. Seven primer pairs amplified 31 alleles, or on average 4.4 alleles per locus. UPGMA cluster analysis, based on the Jaccard similarity coefficient, revealed that among the ten samples declared as ‘Polana’ plantlings only five were genetically identical to any of the other samples. The cluster analyses also exposed that none of the ten samples declared as ‘Polana’ seedlings were in fact identical or even closely related to the ‘Polana’ reference cultivar or any of the other reference cultivars. These findings clearly show that the genetic identity of primocane raspberry plantlings , currently sold in Bosnia and Herzegovina, needs to be tested using objective and reliable methods rather than simple morphologic observation.

Postharvest Auxin and Methyl Jasmonate Effect on Anthocyanin Biosynthesis in Red Raspberry (Rubus idaeus L.)

Fruit color is fundamental for consumer acceptance. There is evidence that plant growth regulators, such as indole-3-acetic acid (IAA) and methyl jasmonate (MJ), are related to the inhibition or increase of flavonoids in red raspberries (Rubus idaeus L.). We evaluated the effect of IAA and MJ treatment in the anthocyanin content in red raspberries cv. Autumn Bliss. Ethylene, IAA, and MJ levels were determined, as well as the relative transcript levels of anthocyanidin synthase (ANS, leucocyanidin oxygenase; EC 1.14.11.19), dihydroflavonol 4-reductase (DFR; dihydrokaempferol 4-reductase; EC 1.1.1.219), and MYB10, a transcriptional regulator of the anthocyanin pathway in raspberries were also determined. The MJ-treated fruits developed an intense red color 2 days after harvest (DAH) and prior to anthocyanin accumulation, which was associated with an increase in the relative expressions of MYB10, ANS, and DFR. Five DAH, the anthocyanin and the total phenolic contents were lower in the IAA-treated fruit than the control group. These effects were related to the inhibition of MYB10 and ANS transcription and correlated to changes in IAA and MJ contents in the fruit flesh. These results suggest that anthocyanin metabolism is regulated by the interplay of multiple hormonal signs, including IAA and MJ, affecting specific steps during raspberry maturation, such as transcription factors of the anthocyanin pathway.

‘Autumn Bliss’ raspberry production using different plant densities in the Mexican central valley

The interest for raspberry (Rubus idaeus L.) cultivation in Mexico is increasing and there are several regions with potential for raspberry production. We must generate technological knowledge for these places. One of the systems for raspberry production is the multiannual cropping, where defining cane density becomes important in order to enhance plant yield and fruit quality. This research was done in the Mexican central valley in order to determine the effect of cane density on yield, fruit quality and cane growth of fall bearing red raspberry 'Autumn Bliss'. The main objective was to define the primocane density with the highest yield. Four treatments were analyzed in a two-year row plantation (10, 20, 30 and 40 primocanes m-2). Each treatment had four replications, which were distributed in a randomized complete block design. Primocane density did affect neither the date for onset of harvest, which was observed on May 19, 2008, nor the harvest period, which was 54 d long. Densities of 40 primocanes m-2 had yields near 1.99 kg m-2, which became on an estimate for raspberry yields superior to that from the national average. Fruit quality and size were not affected with the highest cane density from this study. It is concluded that 40 primocanes m-2 are recommended for multiannual plantations in row in the central valley of Mexico.

New cultivars for quality production of primocane fruiting raspberries enriched in healthy compounds

Raspberry production is in evolution due to increasing consumer interest in the health benefits of antioxidant molecules (AOM) in the fruits. The objective was to define primocane fruiting raspberry cultivars with higher quality in terms of bioactive compounds and to conceive innovative cultural practices such as substrate production systems adapted to specific cultivars. The comparison of agronomic parameters and the fruit quality of 11 cultivars ('Amira', 'Autumn Bliss', 'Brillance', 'Joan J', 'Erika', 'Heritage', 'HimboTop', 'Imara', 'Kweli', 'Polka', 'Sugana') in 2012 and 7 cultivars ('Brillance', 'Chambord', 'Deauville', 'Imara', 'Kwanza', 'Kweli', 'Paris', 'Versaille') in 2013 and 2014 showed a very high variation in bioactive compounds (vitamin C, total phenolics, anthocyanins, ellagitannins) and antioxidant capacities (FRAP, ORAC). Overall, the variation in antioxidant capacities of the fruits among cultivars was related to their bioactive compound content. Cultivars rich in the major phytochemicals showed higher antioxidant activities. Interesting cultivars concerning AOM in fruits were defined and discussed to be used in breeding programs. Furthermore, the results of the cultivar trials in 2013/14 were used to optimise substrate production of primocane fruiting cultivars in the climates of central Europe. For early fruiting cultivars such as 'Kweli', 'Paris' and 'Rubifall' the production system on substrate with plantations in May 2013 followed by 3 consecutive harvests (autumn 2013, summer 2014, autumn 2014) was well adapted and gave high yields with up to 6.9 kg fruits m-2 over two years. However, for late fruiting cultivars such as 'Chambord' and 'Deauville', the production system with plantations in May 2013 followed by only 2 consecutive harvests (a small one in autumn 2013 and a large one in early summer 2014) can be recommended for high profitability.

SSR fingerprinting of a German Rubus collection and pedigree based evaluation on trueness-to-type

Eighty-two genotypes of Rubus available in germplasm collections, nurseries and home gardens were collected and evaluated using a set of 16 simple sequence repeat (SSR) markers to estimate the level of genetic diversity and relatedness of the germplasm and for testing them on trueness-to-type. Each of the 16 SSRs was successful in amplifying alleles from most genotypes. Fifteen of the markers produced polymorphic bands, whereas marker RhM023 was monomorphic. The polymorphic information content among genotypes varied from 0.056 to 0.83 with an average of 0.348. A neighbor-joining analysis allocated the genotypes to four major clusters containing 11, 24, 39 and eight genotypes, respectively. Cluster I consists of floricane-fruiting cultivars originating from the Scottish and/or British breeding programs or cultivars which have those cultivars in their pedigree. Cluster II included cultivars that have ‘Autumn Bliss’ or ‘Tulameen’ in their pedigree. Cluster III consists of summer-bearing raspberry cultivars, some primocane-fruiting cultivars, and a few intermediate summer-fall-bearing types. Cluster IV consists of the blackberry ‘Navaho’ (R. fruticosus L.), the interspecific hybrid ‘Dorman Red’ and a few other raspberry varieties. A number of yellow fruited varieties was dispersed on three different clusters suggesting a convergent evolution of this trait. The pedigree of several genotypes could be confirmed using a Pedimap based approach, whereas other cultivars were found to be genetically identical. The results disclose the alarming narrow genetic base of Rubus resources in Germany. Broadening of this base is urgently needed.

Patterns of nectar and pollen presentation influence the attractiveness of four raspberry and blackberry cultivars to pollinators

SummaryFloral rewards such as nectar and pollen have a major influence on successful pollination and fruit-set, even in selffertile Rubus sp. (Rosaceae), which include most cultivated raspberries and blackberries. A 2-year study was designed to examine the diurnal dynamics of nectar secretion and pollen shedding in the raspberry cultivars ‘Autumn Bliss’ and ‘Malling Exploit’, and in the blackberry cultivars ‘Arapaho’ and ‘Hull’, in order to establish the effect of these traits on floral attractiveness to various insect visitors. The volume of nectar secreted per flower was measured using calibrated capillaries, and the concentrations of sugars in the nectar were measured using a hand-held refractometer. The four Rubus cultivars differed in their patterns of nectar and pollen presentation. Volumes of nectar and concentrations of sugars were influenced by year, cultivar, age of the flower, and time of sampling. The four cultivars exhibited different patterns of nectar secretion over the 2 years. In year-1, an early morning peak in nectar volume was followed by a rapid decline, while the concentrations of sugars increased during the day. In year-2, both the volume of nectar and the concentrations of sugars increased from the morning to the afternoon. The patterns of pollen presentation were similar in both years of study. Anther dehiscence took only 3 - 8 h per flower in the poorest nectar producer, ‘Arapaho’; while, in cultivars with higher nectar yields, pollen shedding lasted for 6 - 10 h. Pollen-shedding flowers secreted significantly higher volumes of nectar, with significantly lower concentrations of sugars, compared to pre-pollen-shedding flowers in year-1. The concentrations of sugars in the nectar were higher in both raspberry cultivars than in the blackberry cultivars, but both blackberry cultivars were as attractive to bees due to their more appealing nectar sugar composition. Bees were more attracted to flowers of cultivars which simultaneously offered ample nectar and some pollen (i.e., ‘Autumn Bliss’, ‘Malling Exploit’, and ‘Hull’) than to flowers with a rapid rate of pollen shedding, but a low nectar yield (i.e., ‘Arapaho’). Higher rates of bee-mediated cross-pollination may provide economically important increases in fruit yields and better quality fruit.

<b>Environmental and genetic variation in the post-harvest quality of raspberries in subtropical areas in Brazil

Raspberry is an economically important berry crop that contains numerous phenolic compounds with potential health benefits. It is known that the chemistry content is affected by processing factors, but limited information is available on the influence of cultural factors or genotype. To clarify this issue, this work aimed to characterize the following raspberry cultivars Polana, Autumn Bliss, Heritage, Batum, Golden Bliss, hybrid Boysenberry and black raspberry from Mantiqueira Mountains (Campos do Jordao city, Sao Paulo State, Cwa climate, mesothermal with dry winter, commonly named tropical de altitude, according to Koppen classification) and Alto do Rio Grande (Lavras city, Minas Gerais State, Cwb climate, with dry winter and summer temperate), two areas subtropical in Brazil, and quality attributes. The fruits were used for the following analysis: mass, size, number of drupelets, color, total acidity, soluble solids, total soluble solids / titratable acidity (TSS / TA), moisture and ash. The results revealed strong influence of growing site on fruit quality as well as the existence of variation among cultivars. Fruits produced in Mantiqueira Mountains had larger and higher TSS / TA. On the other hand, the growing raspberries in Alto do Rio Grande provided greater color tone, increased acidity, and low ratio of total soluble solids and total acidity.