Commercial Raspberry Research Articles

Thrips species occurring in red raspberry, Rubus idaeus L., in South Norway

Aim of study: Thrips in raspberry crops are receiving attention in Scandinavian raspberry production because of the increasing sighting of their presence in the flowers. Specific information on thrips species occurring in raspberry and their damage potential is scarce, making thrips management challenging. Therefore, this study aimed to identify thrips in the flowers of cultivated raspberry, Rubus idaeus L., in South Norway. Area of study: Sogndal, Luster and Frogn, Southern Norway Material and methods: Adult thrips were sampled from eight commercial raspberry orchards in the counties Vestland and Viken in June-July 2022. Thrips were mounted using Hoyer’s medium and a total of 213 specimens were morphologically identified. Main results: Five species of thrips were found, Thrips fuscipennis Haliday, Thrips major Uzel, Thrips flavus Schrank, Thrips vulgatissimus Haliday and Thrips brevicornis Priesner. Most specimens were T. flavus, followed by T. fuscipennis and T. vulgatissimus. Research highlights: Among the five species found, only T. fuscipennis has previously been reported in cultivated raspberry, but all five species are associated with flowers of many plants. The findings imply a larger and more geographically varied thrips fauna on raspberry than currently documented. This should be taken into account in future studies on thrips management in raspberry.

Anthocyanins and the Antioxidant Capacities of Wild Berries that Grow in Shizuoka, Japan

ABSTRACT Fruits from five wild edible berries that grow in the eastern region of Shizuoka (Japan) were collected, and their antioxidant activities were evaluated using the ORAC, DPPH, FRAP, and ABTS assays to obtain basic scientific knowledge of these species. Among the Shizuoka wild berries tested, Rubus microphyllus L. fil. exhibited the highest antioxidant activity, which is equivalent to that of commercial raspberry (Rubus idaeus L.). Furthermore, anthocyanins from these wild berries were analyzed using quantitative 1H NMR spectroscopy. Cyanidin-3-glucoside and pelargonidin-3-glucoside were detected in Shizuoka wild berries, with the latter identified as the characteristic anthocyanin. The present study revealed that Shizuoka wild berries are rich in natural antioxidants and pigments and are therefore potentially beneficial for reducing the risks of associated with lifestyle-related diseases in consumers.

Nutritional Qualities of Different Commercial Raspberries Consumed in Morocco

Nutritional Qualities of Different Commercial Raspberries Consumed in Morocco

Integration of Rubus yellow net virus in the raspberry genome: A story centuries in the making

Rubus yellow net virus (RYNV) belongs to genus Badnavirus. Badnaviruses are found in plants as endogenous, inactive or activatable sequences, and/or in episomal (infectious and active) forms. To assess the state of RYNV in Rubus germplasm, we sequenced the genomes of various cultivars and mined eight raspberry whole genome datasets. Bioinformatics analysis revealed the presence of a diverse array of endogenous RYNV (endoRYNV) sequences that differ significantly in their structure; some lineages have nearly complete, yet non-functional genomes whereas others have rudimentary, short sequence fragments. We developed assays to genotype the main lineages as well as the only known episomal lineage present in the United States. This study discloses the widespread presence of endoRYNVs in commercial raspberries, likely because breeding efforts have focused on a limited pool of germplasm that harbored endoRYNVs.

Integration of Raspberry Pi and antennas for multiplexing digital signals over a fiber optical communication system

A Fiber Optical Communication System (FOCS) is used to experimentally demonstrate the transmission of multi-channel information of two High Definition (HD) video signals and 18 digital TV channels. These signals are supplied using commercial Raspberry Pi boards and digital TV Antennas, respectively. Both digital signals and lightwaves of a couple of Distributed Feedback (DFB) lasers with wavelengths located at 1547.5 and 1552.5 nm interact with two Mach-Zehnder Intensity Modulators (MZ-IM). The resulting modulated optical signals from each modulator are combined by using an optical coupler. The combined optical field is amplified and transmitted through 30 km of single-mode optical fiber. To demultiplex the combined optical signals, a bandpass optical filter is used, then a PIN-photodetector is connected to recover HD video signals and the 18 digital TV channels. The measured electrical spectrum of the received signals shows that the transmission is performed without interference and the multi-channel information is successfully received in an HD display. The use of wavelengths with linewidths of 10 MHz and an optical fiber with a chromatic dispersion of 17 ps/nm-km allows for a maximum bit rate of approximately 11 Gbps to be achieved numerically. This result guarantees that HD video signals can be experimentally transmitted successfully with Bit Error Rate (BER) values between 10-6 and 10-15 when the optical power of lasers is tuned between 7 and 9 dBm.

Widely targeted metabolome profiling of different plateau raspberries and berry parts provides innovative insight into their antioxidant activities.

Raspberries are highly nutritious and have powerful antioxidant properties, making them functional berries with positive effects on physiological functioning. However, there is limited information available on the diversity and variability of metabolites in raspberry and its parts, especially in plateau raspberries. To address this, commercial raspberries and their pulp and seeds from two plateaus in China were subjected to LC-MS/MS-based metabolomics analysis and evaluated for antioxidant activity using four assays. A metabolite-metabolite correlation network was established based on antioxidant activity and correlation analysis. The results showed that 1661 metabolites were identified and classified into 12 categories, with significant variations in composition between the whole berry and its parts from different plateaus. Flavonoids, amino acids and their derivatives, and phenolic acids were found to be up-regulated in Qinghai's raspberry compared to Yunnan's raspberry. The main differently regulated pathways were related to flavonoid, amino acid, and anthocyanin biosynthesis. The antioxidant activity of Qinghai's raspberry was stronger than Yunnan's raspberry, and the order of antioxidant capacity was seed > pulp > berry. The highest FRAP (420.31 µM TE/g DW) values was found in the seed of Qinghai's raspberry. Overall, these findings suggest that the environment in which the berries grow can affect their chemical composition, and comprehensive exploitation and cultivation of whole raspberry and its parts from different plateaus can lead to new opportunities for phytochemical compositions and antioxidant activity.

The predation impact of ruby-throated hummingbird, Archilochus colubris, on spotted-wing drosophila, Drosophila suzukii, in raspberry, Rubus idaeus

Hummingbirds require arthropods in their diet and may consume 2000 small insects per day, including drosophilids, when nesting. In New York, we investigated the use of feeders to attract Ruby-throated Hummingbirds, Archilochus colubris (Linnaeus, 1758), into red raspberry, Rubus idaeus L., to encourage predation of the spotted-wing drosophila, Drosophila suzukii Matsumura. We investigated whether fly populations and fruit infestation would be reduced in the half of the field with feeders compared to the half without. Over four years, 2015–2018, 81% of 266 hourly observations of hummingbird behavior found they were occupying the field when utilizing the feeders, supporting opportunities for predation on D. suzukii. In 2016 to 2018, when maximal hummingbird sightings were reached, significant reductions in D. suzukii trap counts and fruit infestation levels were obtained in some weeks in the half of the field provided with feeders at a density of 62 feeders/hectare. Compared to the half without feeders, the final tally of cumulative trap counts and fruit infestation levels were lower in the half of the field treated with feeders in all years. In comparing two paired commercial raspberry fields (in 2020), one with feeders at a density of 151 feeders/hectare and the other without feeders, presence of feeders significantly reduced trap counts in most weeks during the fruiting season. No Ruby-throated Hummingbirds were observed in the commercial field without feeders. Hummingbirds may protect fruit from D. suzukii when they are encouraged with feeders to visit and occupy raspberry plantings. The presence of hummingbirds in raspberry fields has the potential to contribute to a D. suzukii integrated management program and reduce the reliance on pesticides.

Effects of four irrigation regimes on yield, fruit quality, plant water status, and water productivity in a furrow-irrigated red raspberry orchard

Due to drought intensification in Mediterranean-type climates, raspberry growers need to implement irrigation scheduling to save water without decreases in yield and fruit quality. A study was performed to evaluate the effects of four irrigation levels on yield (Y), fruit number (FM2), fruit weight (FW), water productivity (WP), fruit quality (titratable acidity (TA), soluble solids (SS), weight to volume ratio (WV)), midday stem water potential (Ψstem), and water stress integral (WSI) in a furrow-irrigated red raspberry (Rubus ideaus L. ‘Heritage’) orchard. An experimental plot was established within a commercial raspberry orchard located in the Colbún valley, Maule Region, Chile, during the 2012/13 and 2013/14 growing seasons. The irrigation treatments were 125 (T1, farmer irrigation management), 100 (T2), 75 (T3) and 50% (T4) of crop evapotranspiration (ETc). The results showed significant differences among treatments for Y and FM2, with the highest and lowest values observed under the T3 and T1 treatments, respectively. The T4 treatment had the highest values of WSI and WP compared to the other treatments. The effects of irrigation levels were not significant for SS and WV, but the lowest TA was observed under the T1 treatment. Results suggested that water application based on the 75% of ETc associated with Ψstem > −1.0 MPa was the most appropriate irrigation strategy for the furrow-irrigated red raspberry orchard because it had the highest Y (9.25 kg m−2) and saved water by 20–28% compared to the 125% and 100% ETc treatments.

Fruit Qualities of Interspecific Hybrid and First Backcross Generations between Red Raspberry and Rubus parvifolius

Interspecific hybridization is useful in raspberry (Rubus idaeus L. ssp. idaeus) breeding to introgression of traits such as heat or cold tolerance, and excellent fruit qualities. Rubus L. wild species in Asia, including Rubus parvifolius L., have been attracting a great deal of attention as sources of new traits in breeding raspberry and blackberry (Rubus fruticosus Agg.). We previously developed and selected IPI-1 and IPI-3 first backcross (BC1) hybrids, [‘Indian Summer’ (R. idaeus ssp. idaeus) × R. parvifolius] × ‘Indian Summer’, as raspberry cultivars adapted to the warm climate in parts of Japan. In this study, we investigated the growth, morphological traits, and fruit qualities, such as sugar, organic acid, anthocyanins, and carotenoids, of each of these IPI lines over a 2-year period to discern their potential as commercial raspberry cultivars. IPI lines had the characteristic of primocane fruit with overflowing from side buds while the parent, IP-1 (‘Indian Summer’ × R. parvifolius), did not. IPI lines showed significantly lower values in anthocyanin content than red raspberry ‘Skeena’, while showing higher carotenoid contents. This study is the first research about fruit qualities such as anthocyanin and carotenoid content of BC1 hybrids using Japanese wild Rubus species.

Partial Budget Analysis of Exclusion Netting and Organic-certified Insecticides for Management of Spotted-wing Drosophila (Diptera: Drosophilidae) on Small Farms in the Upper Midwest.

Drosophila suzukii Matsumura (Diptera: Drosophilidae), or spotted-wing drosophila, is an invasive pest first detected in the United States in 2008. Although D. suzukii can use many cultivated fruit as hosts, raspberries are considered 'most at risk' for infestation. Conventional broad-spectrum insecticides are proven effective D. suzukii controls and can be economically profitable when combined with integrated pest management (IPM) on large-scale commercial raspberry farms. It remains unclear, however, whether organic controls are cost-effective strategies, particularly for farms operating on a small-scale seasonal basis, as is common in the Upper Midwest. The purpose of this paper is to explore the efficacy of two organic D. suzukii controls-exclusion netting for high tunnels and organic insecticides for open plots using data available from different field trials-and to ascertain whether any economic benefits of the organic controls outweigh treatment costs for small-scale raspberry operations under different risk scenarios. The field trials suggest that the organic treatments are effective controls for D. suzukii infestation and economically profitable. The exclusion netting treatment produced positive net returns compared to the alternative of no treatment and economically outperformed the organic-certified insecticide treatment for several yield, price and infestation scenarios. As D. suzukii infestation rates increased, net returns improved for both organic treatments. The economic results were robust across a range of yields and prices, suggesting that in almost all scenarios small scale organic raspberry growers benefit economically from the application of exclusion netting on high tunnels and insecticides for open plots.

Probiotic viability, viscosity, hardness properties and sensorial quality of synbiotic ice creams produced from goat’s milk

This research aimed to examine the probiotic viability of bacteria, rheological and sensorial properties in synbiotic ice creams produced from goat’s milk combined with probiotic culture and prebiotics. Tagatose, Litesse ultra and polydextrose (as prebiotics) were used in ice cream production and mixtures and these mixtures were inoculated with Bifidobacterium bifidum, Lactobacillus paracasei and Bifidobacterium longum combined culture. Frozen raspberry fruits, commercial raspberry and blackberry fruit purees were used as taste flavor enhancers in synbiotic ice cream. Four different ice cream types were produced including control sample. Probiotic bacteria viability, apparent viscosity, hardness and sensory properties were examined during the 120-day- storage. It was determined that frozen fruit and fruit purees addition and using prebiotics significantly affected the Lactobacillus paracasei and Bifidobacterium spp. viability and color, appearance, flavor, taste and overall sensory scores of the synbiotic goat’s milk ice creams (P < 0.05). Synbiotic ice cream samples maintained their probiotic properties during storage and were generally well appreciated in terms of sensory properties.

Evaluation of physicochemical properties in three raspberries (Rubus idaeus) at five ripening stages in northern China

To evaluate the physicochemical properties of raspberries (Rubus idaeus L.) at five ripening stages in Shanxi, northern China (non-traditional area of cultivation), 25 physicochemical indexes including 5 anthocyanins and 10 phenolic compounds by HPLC-MS, fruit weight, moisture content, soluble solids content, sugar-acid ratio (SAR), of three commercial cultivars, cv. Reveille, Tulameen and Heritage, were investigated. The fruit qualities of the three cultivars were close to those of fruit produced in the traditional cultivation areas, especially cv. Tulameen at the overripe stage (Stage 5), which had the largest fruit weight of 4.20 g, and the highest SAR of 4.01 and total anthocyanin content of 103 mg 100 g−1 fresh weight. By intercropping the annual-fruiting ‘Heritage’ and the biennial-fruiting ‘Reveille’ and ‘Tulameen’, the raspberry season in Shanxi, China was extended without a break from mid-June to early October. The unripen raspberries (Stages 1 and 2) with high levels of non-anthoycanin phenols, especially ellagictannin were suitable as a plant-derived polyphenol materials. The ripe raspberries (Stages 3 and 4) with a high anthocyanin level and SAR, were suitable for fresh use and processing. The overripe raspberries (Stage 5) which quickly rotted, with the highest anthocyanin level, moisture content and SAR, were suitable as raw materials for anthocyanin extraction. Cyanidin-3-sophoroside, cyanidin-3-glucoside, and cyanidin-3-rutinoside were the main anthocyanins in cv. Heritage, Tulameen, and Reveille, respectively. Thus, commercial raspberries can be utilized on the basis of their properties and active compounds at different ripening stages, and we provide basic data for their production in Shanxi, northern China.

Evaluation of hop (Humulus lupulus) as a repellent for the management of Drosophila suzukii

Over the past decade, the spotted-wing drosophila, Drosophila suzukii Matsumara has become one of the most important pests of soft- and stone fruits throughout Europe. Currently, the majority of growers still rely heavily on a limited portfolio of chemical foliar spray insecticides. Alternative strategies such as attract and kill (pull) or behavioral control systems that repel or deter D. suzukii from damaging fruits (push) are less common. We evaluated the potential of hop (Humulus lupulus L.), as a repellent for the Integrated Pest Management of D. suzukii, in controlled greenhouse conditions as well as at commercial field sites. In greenhouse cage tests on fruit or attractant medium, the positive controls thymol and 1-octen-3-ol as well as certain hops significantly reduced larval infestation levels compared to an untreated control, while other hop products showed only numerical reduction in infestation. A controlled field trial on raspberries (Rubus idaeus L.) failed to replicate these results, both for the positive control repellents as for the hop samples. In field experiments in commercial raspberry and blackberry (Rubus fruticosus L.) plantations, no significant reduction in oviposition or differences in population density could be observed for the hop treated plots as compared to the untreated. Through SPME headspace analysis of the hops, a number of compounds were associated with the efficacy observed in the greenhouse, even though different hop varieties were found to have notably different volatile profiles.

Testing a Novel Attract-and-Kill Strategy for Drosophila suzukii (Diptera: Drosophilidae) Management.

The invasion of the spotted wing drosophila, Drosophila suzukii Matsumura, across the Americas and Europe has led to increased insecticide applications to protect fruit crops. This insecticide usage conflicts with integrated pest management programs, as well as harvest, export, and pollination services in the affected crops. A novel management tool was assessed against D. suzukii that may mitigate these conflicts. HOOK SWD, an attract-and-kill (A&K) formulation applied as a sprayable bait, was evaluated for three growing seasons in two berry crops in New Jersey and California. In blueberry crops treated with HOOK SWD, fruit infestations by D. suzukii were 2–8 times lower than in untreated crops. In trials in commercial raspberry fields, weekly or biweekly HOOK SWD applications combined with a single grower standard D. suzukii-targeted cover spray resulted in nearly 2–5 times fewer fruit infestations compared to the grower standard cover spray alone. Assays of the residual activity of HOOK SWD resulted in more than 78–93% adult D. suzukii mortality when exposed to raspberry leaves after the formulation had aged for 35 d in the field under plastic hoop houses. These results suggest that this A&K strategy can be integrated in D. suzukii management programs.

Identification and risk assessment of spinosad resistance in a California population of Drosophila suzukii.

The bioinsecticide spinosad is among the most widely used insecticides for managing spotted-wing drosophila, Drosophila suzukii (Matsumura), and is critical for preventing fruit infestation in organic berry production. Recent reports, however, have raised concerns that the efficacy of this material is declining in fields near Watsonville, CA, a major hub of commercial berry production in the USA and the first location where D. suzukii was reported in North America. In this study, we performed dose-response analyses on D. suzukii from commercial raspberry plantings near Watsonville as well as a second untreated site in California using a widely implemented bioassay protocol. We found that Watsonville flies exhibited spinosad LC50 values 4.3-7.7 times higher than those from the untreated location and 11.6-22.4 times higher than previously reported susceptible baselines. Additionally, tolerance to spinosad continued to increase after additional selection for five generations, though this result was only statistically significant after prolonged exposure to residues. These findings confirm that spinosad resistance is emerging in the Watsonville area and document the first known occurrence in the USA, presenting an urgent need for the development of alternative management strategies to control this pest. Additional work is needed to resolve the underlying molecular mechanism(s) that confers spinosad resistance in D. suzukii and assess the potential for this trait to spread into new populations. © 2018 Society of Chemical Industry.

The costs and benefits of pollinator dependence: empirically based simulations predict raspberry fruit quality.

Globally, agriculture increasingly depends on pollinators to produce many seed and fruit crops. However, what constitutes optimal pollination service for pollinator-dependent crops remains unanswered. We developed a simulation model to identify the optimal pollination service that maximizes fruit quality in crops. The model depicts the pollination (i.e., autonomous self-fertilization, pollen deposition) and post-pollination (i.e., pollen germination, and time from germination to ovule fertilization) processes leading to fruit and seed set and allows for negative flower-pollinator interactions, specifically pistil damage. We parameterized and validated the model based on empirical observations of commercial raspberry in western Argentina. To assess the effects of pollination intensity for fruit production, we conducted simulations over a range of visit number per flower by the two primary managed pollinators worldwide, Apis mellifera and Bombus terrestris. Simulations identified that ~15-35 visits per flower by A.mellifera or ~10-20 visits by B.terrestris provide adequate pollination and maximize raspberry fruit quality (i.e., estimated as the proportion of ovules that develop into drupelets). Visits in excess of these optima reduce simulated fruit quality, and flowers receiving >670 honey bee visits or >470 bumble bee visits would produce fruits of poorer quality than those receiving no bee visits. The simulations generated consistent, unbiased predictions of fruit quality for 12 raspberry fields. This model could be adapted easily to other animal-pollinated crops and used to guide efficient pollinator management in any agro-ecosystem.

Epigeal and Flight Activity of Coleoptera in a Commercial Raspberry Plantation and Adjacent Sites in Southern Quebec (Canada): Introduction and Nitidulidae

Epigeal and Flight Activity of Coleoptera in a Commercial Raspberry Plantation and Adjacent Sites in Southern Quebec (Canada): Introduction and Nitidulidae

Alternatives to Current Fumigation Practices in Western States Raspberry

Red raspberry production in the western United States is heavily reliant on preplant soil fumigation to ensure the successful establishment and productivity of a planting. However, due to issues related to the regulation, availability, and economics of soil fumigation, alternatives are needed for current fumigation practices. Trials were conducted in commercial raspberry fields in California and Washington to evaluate alternatives to current fumigation practices in each region. In Washington, tarped bed fumigation with 1,3-dichlorpropene (1,3-D):chloropicrin (Telone C-35) performed as well as, and sometimes better than, the industry standard nontarped broadcast fumigation with Telone C-35 for the control of the soilborne pathogen Phytophthora rubi and the plant-parasitic nematode Pratylenchus penetrans. In one of the Washington trials, yield of raspberry grown in tarped bed-fumigated areas was 47% greater than the yield of plants grown in nontarped broadcast-fumigated areas. In California, a combination of chloropicrin:1,3-D (Pic-Clor 60) performed as well as the industry standard of methyl bromide:chloropicrin. Raspberry plants grown in soil fumigated with either of these fumigants were approximately 26% taller than plants grown in nonfumigated soil. Our results indicate that there are viable fumigation alternatives to the current fumigation systems used in Washington and California raspberry production systems.

Evaluation of vigor and winter hardiness of black raspberry breeding populations (Rubus occidentalis) grown in the southeastern US

Demand for fresh berry products continues to grow in the United States; however, commercial raspberry production in the southeastern US is difficult because cultivars are not well adapted to the warm climate and fluctuating winter temperatures, where heat degrades plant vigor and fruit quality, and warm spells in mid to late winter can cause low chilling plants to break bud too early. Recent research about the health benefits of a polyphenolic-rich diet has led to a resurgence of interest and breeding efforts in black raspberry, and is the driving factor for this particular research. Two half-sib populations, ORUS 4304 and ORUS 4305 (307 progeny total) were planted in Jackson Springs, North Carolina in 2012. From fall 2012-spring 2015, a number of traits were measured on each plant, among them vigor, winter hardiness, and heat damage, analyzed in several different ways. Plant vigor increased or decreased over harvest seasons based on individual differences in the segregating plant population, but also showed correlations with temperature, i.e., less vigorous plants were more susceptible to damage by heat or cold. Overall, ORUS 4305 was less vigorous than ORSU 4304. As is the case with most raspberries grown in the southeast, vigor in general is expected to decrease over time; however, certain individuals show transgressive segregation for the trait. Linkage mapping for both populations is underway to identify and validate QTL for vigor, winter hardiness, heat tolerance, and other traits within black raspberry. Ultimately, we hope to gain a more complete understanding of black raspberry physiology and genetics to make breeding commercial quality cultivars a possibility in the southeast.

Effects of the growing season extension on Polish primocane-fruiting raspberry cultivars

Three primocane-fruiting raspberry cvs, Polana, Polka and Polesie, were evaluated for their performance under various early spring coverings during the 2010-2013 growing seasons. Three cultivation techniques were compared: covering plants with perforated plastic cover, covering plants with fibre cover (in early spring, for a period of about 1 month), mowing of young canes in the middle of May; the control combination were plants without covers and not mown. During each growing season, plant growth vigour, yielding and fruit quality (soluble solids and vitamin C content) were assessed. The use of low covers (perforated plastic cover and fibre cover) advanced the fruit ripening of the tested cultivars by about 2 weeks. The covers of raspberry plants also increased significantly yield of the early fruit (harvested in July and August) compared with the control. The investigated techniques can be recommended for implementation and use on commercial raspberry plantations to force early fruiting and thus increase their production potential in the summer-autumn period.