Trichopria anastrephae as a Biological Control Agent of Drosophila suzukii in Strawberries.

In South America, the resident pupal parasitoid Trichopria anastrephae Costa Lima (Hymenoptera: Diapriidae) is a potential biological control agent of the pest Drosophila suzukii Matsumura (Diptera: Drosophilidae). In the present study, we (1) examined the behavior of T. anastrephae towards different host (D. suzukii) and host-substrate (strawberry) cues in choice and non-choice bioassays in laboratory, and (2) examined the density-dependent parasitism of T. anastrephae in D. suzukii-infested strawberries in a greenhouse. When given a choice, female parasitoids walked longer over chambers with fruits infested with eggs, larvae, or pupae of D. suzukii, when compared to healthy uninfested strawberries, and over overripe fruits when compared to unripe or ripe fruits. In the greenhouse assay, we observed an increase in parasitism and a decrease in the number of D. suzukii emerging per fruit with an increase in the number of parasitoids released. Our results allow a better understanding of the behavior and parasitism of T. anastrephae in D. suzukii-infested strawberries and provide useful data for potential biological control programs using this parasitoid.

Survival and nutritional requirements for overwintering Drosophila suzukii (Diptera: Drosophilidae) in Kentucky.

The ability to cope with novel climates is a key determinant of an invasive species' success. Drosophila suzukii (Matsumura, 1931) is an invasive fruit pest, and its seasonality varies across its range. Current evidence suggests that D. suzukii occurs year-round in warmer climates but has low overwintering survival in colder climates and relies on refuges or reinvades each spring. Here, we assessed the capacity of D. suzukii ability to overwinter in Kentucky, a temperate mid-latitude state with relatively mild but variable winters. We tracked year-round population changes for 3 yr and observed the highest populations in early winter months. Following an annual population crash in winter, small numbers of flies remained through the late winter and spring. We also conducted outdoor cage studies to determine the extent to which food resources and microhabitat impact survival and postwinter fecundity under natural conditions. Flies with no food had poor survival during the warmest periods of winter, and flies in all treatments had lower survival in the coldest month. Provisioning flies with either artificial diet or wild berries improved survival. As a follow-up, we determined whether D. suzukii could survive and reproduce after long-term exposure to a typical winter temperature on various wild berries. Drosophila suzukii had the highest survival on privet (Ligustrum sp.), but all berry types yielded higher survival than flies without food. Our results suggest that noncrop berries play an important role for overwintering D. suzukii, and as winters warm the availability of wild berries could influence early-season populations.

Genomic region and origin for selected traits during differentiation of small-fruit cultivars in Japanese apricot (Prunus mume).

The Japanese apricot (Prunus mume) is a popular fruit tree in Japan. However, the genetic factors associated with fruit trait variations are poorly understood. In this study, we investigated nine fruit-associated traits, including harvesting time, fruit diameter, fruit shape, fruit weight, stone (endocarp) weight, ratio of stone weight to fruit weight, and rate of fruit gumming, using 110 Japanese apricot accessions over four years. A genome-wide association study (GWAS) was performed for these traits and strong signals were detected on chromosome 6 for harvesting time and fruit diameters. These peaks were shown to undergo strong artificial selection during the differentiation of small-fruit cultivars. The genomic region defined by the GWAS and XP-nSL analyses harbored several candidate genes associated with plant hormone regulation. Furthermore, the alleles of small-fruit cultivars in this region were shown to have genetic proximity to some Chinese cultivars of P. mume. These results indicate that the small-fruit trait originated in China; after being introduced into Japan, it was preferred and selected by the Japanese people, resulting in the differentiation of small-fruit cultivars.

The Influence of the Explant's Type on the Performance of Synthetic Seeds of Blackberry (Rubus spp.).

In vitro propagation, also known as micropropagation, has become the most widely employed method for blackberry propagation, as it overcomes the limitations of the traditional asexual propagation methods (mainly layering and cutting). In this context, synthetic seed technology represents a strategy to enhance the productivity of in vitro propagation and facilitates the exchange of plant materials between laboratories, contributing to germplasm conservation. This study aimed to identify the most suitable vegetative propagule for the encapsulation of blackberry. To this end, uninodal microcuttings (nodes) and the base of clumps were used to produce synthetic seeds for the cultivars Thornfree and Chester. Forty-five days after sowing, viability (percentage of green propagules without browning or necrosis), regeneration (percentage of propagules that sprouted and rooted simultaneously), number of shoots produced, shoot length, number of roots produced, root length, and the fresh and dry weights of the plantlets were measured. The results demonstrated that both considered propagules allowed us to obtain satisfactory regeneration rates. However, plantlets originating from the encapsulated clump's base had more shoots and roots, resulting in greater fresh and dry weights than the plantlets derived from encapsulated nodes. Therefore, for achieving more robust plantlets and enhancing overall procedural efficiency, we recommend using the base of clumps as a propagule for blackberry encapsulation.

Scientific support of small fruit growing in Russia and prospects for its development.

It is possible to achieve the target indices of the Russian Doctrine of Food Security (self-sufficiency in fruits and berries should be at least 60 %) by combining the competencies of science and business. At present, hundreds of varieties of small fruit crops are included in the State Register of Breeding Achievements Admitted for Use. Domestic breeders have obtained substantial results; the share of their assortment is 79-100 %. Federal Research Center of Horticulture (Moscow) (101 pcs.), Federal Altai Research Center of Agrobiotechnology (Barnaul) (85 pcs.), Michurin Federal Research Center (Michurinsk) (42 pcs.) are the leaders in the number of created hybrids and varieties. Over the past five years, 133 new breeding achievements of traditional small fruit crops have been submitted to the State variety testing, the originators of which are research institutions, private companies and individuals. The creation of modern seed-breeding (nursery-breeding) centers (SBC) on the basis of leading specialized research institutions is expected to be the solution to the problems of modern breeding and nursery breeding and to give impetus to the development of domestic small fruit growing. The research programs of the SBC involve an integrated approach that combines the knowledge and capabilities of researchers from different disciplines, the concentration of a complex analytical instrument base in the Centers of collective use, the using of biotechnological and molecular genetic research, along with traditional methods of breeding. An analysis of the achievements in small fruit growing in research institutions under the jurisdiction of the Ministry of Science and Higher Education of the Russian Federation revealed a huge scientific potential (genetic collections, hybrid funds) for creating competitive commercial varieties and technologies for their cultivation by establishing plantations with certified planting material in accordance with international requirements. Information from literary sources indicates that one of the main criteria for the value of varieties is resistance to harmful viral diseases. The cultivation of such varieties will reduce the cost of producing planting material for small fruit crops of the highest quality categories. In the near future, the most relevant areas for the breeding of small fruit crops will be: breeding for resistance to the most harmful viruses, winter hardiness, increased transportability and long-term post-harvest storage of fruits, suitability for mechanized cultivation, high content of biologically active substances.

Gibberellin Application Improved Bunch Rot Control of Vignoles Grape, but Response to Mechanical Defoliation Varied Between Training Systems.

Late-season bunch rot causes significant crop loss for grape growers in wet and humid climates. For 3 years (2016 to 2018), we integrated prebloom mechanized defoliation (MD) in the fruit zone and bloom gibberellin (GA) applications, either alone or in combination, into the bunch rot control program of Vignoles, a commercially valuable grape variety that is highly susceptible to bunch rot. We hypothesized that both treatments would decrease bunch rot through modification of cluster architecture or fruit zone microclimate compared with vines treated with the standard chemical control program. Grapevines were trained to two popular training systems, four-arm Kniffin (4AK) and high-wire bilateral cordon (HWC). Treatment responses varied between training systems. MD, alone or in combination with GA, reduced bunch rot incidence and severity every year on 4AK-trained vines, an effect attributed mainly to fruit zone improvements. Conversely, MD alone did not reduce bunch rot incidence on HWC-trained vines, despite significant improvements in cluster architecture (reduced number of berries per cluster and cluster compactness). GA applications were more effective than MD at reducing cluster compactness, regardless of training system. As a result, GA reduced bunch rot incidence and severity when applied alone or with MD on 4AK- and HWC-trained vines. All treatments positively improved fruit-soluble sugar concentration on both training systems, while positive effects on titratable acidity were more consistent across training systems with MD.

Deterrent Effects of Essential Oils on Spotted-Wing Drosophila (Drosophila suzukii): Implications for Organic Management in Berry Crops.

Due to concerns about frequent applications of spinosad and other broad spectrum insecticides for managing spotted-wing drosophila (Drosophila suzukii Matsumura, SWD), we investigated the use of essential oils as an alternative to current insecticides. Essential oils from a number of plant species have been studied for their attraction and deterrence of SWD. However, these botanical products have not been thoroughly tested in the field. We conducted laboratory and field studies to determine the efficacy of botanical products, including lavender (Lavandula angustifolia Mill.) oil, catnip (Nepeta cataria L.) oil, KeyPlex Ecotrol® PLUS, and KeyPlex Sporan® EC2 on preventing SWD infestation in raspberry (Rubus idaeus L.) and blueberry (Vacciniumcorymbosum L.) crops. In a two-choice laboratory bioassay, lavender oil, Ecotrol, and Sporan treatments deterred SWD from a yeast-cornmeal-sugar based fly diet. In the field trials, raspberry fruit treated with Ecotrol had lower SWD infestation (6%), compared to the control (17%), and was comparable to spinosad (6%). No differences were seen in blueberry infestation. The combination of essential oils in Ecotrol may work to decrease SWD fruit infestation under certain conditions in the field, however more research is needed on the longevity of these products.

Effect of light and sucrose on photoautotrophic and photomixotrophic micropropagation of Physalis angulata / Efeito da luz e sacarose na micropropagação fotoautotrófica e fotomixotrófica de Physalis angulata

The biotechnological interest in genus Physalis has increased in the last decades, however, there are still few micropropagation studies of this genus. The objective of this study was to evaluate P. angulata photoautotrophic and photomixotrophic micropropagation with gas exchange under seven light spectra and five concentrations of sucrose. Lighting were yellow, blue, white, red, green, red + blue LEDs and natural light filtered by mesh. Sucrose concentrations were 0, 7.5, 15, 22.5 and 30 g.L-1. Phytotechnical, anatomical features and photopigment contents were evaluated through stem and root segment length, leaf number, leaf area, chlorophyll a and b contents, carotenoids, adaxial epidermis, palisadic and spongy parenchyma and abaxial epidermis. The data were compared by Scott-Knott's mean test and principal components analysis using the R software. Comparing the variables within lighting types, it was observed that only the screen treatment, screen-filtered natural illumination, obtained assessment in all variables. Comparing the levels of sucrose, it was observed that the treatment 15 g.L-1 sucrose obtained the highest number of averages with maximum evaluation. It was concluded that the natural light filtered by screen with 50% of shading allowed the photoautotrophic micropropagation of P. angulata. Better development results were observed in photomixotrophic micropropagation with 15 g.L-1 of sucrose.

O interesse biotecnológico em Physalis aumentou nas últimas décadas, porém, ainda existem poucos trabalhos de micropropagação desse gênero. Objetivou-se avaliar sua micropropagação fotoautotrófica e fotomixotrófica com troca gasosa sob sete tipos de iluminação e cinco concentrações de sacarose. Foram utilizados LEDs amarelo, azul, branco, vermelho, verde, vermelho + azul e luz natural filtrada por malha. As concentrações de sacarose foram 0, 7,5, 15, 22,5 e 30 g.L-1. Características fitotécnicas, anatômicas e teor de fotopigmentos foram avaliados através de comprimento de segmento de caule e raíz, número de folhas, área foliar, teores de clorofilas a e b, carotenoides, epiderme adaxial, parênquimas paliçádico e esponjoso e epiderme abaxial. Os dados foram comparados por teste de média Scott-Knott e análise de componentes principais utilizando-se o software R. Comparando-se as variáveis dentro de tipos de iluminação, observou-se que apenas o tratamento screen, iluminação natural filtrada por malha, obteve avaliação máxima em todas as variáveis. Comparando-se os níveis de sucrose, observou-se que o tratamento 15 g.L-1 sacarose obteve o maior número de médias com avaliação máxima. Concluiu-se que a luz natural filtrada por tela com 50% de sombreamento permitiu a micropropagação fotoautotrófica de P. angulata. Observou-se melhores resultados de desenvolvimento na micropropagação fotomixotrófica com 15 g.L-1 de sacarose.

The Influence of Film and Storage on the Phenolic and Antioxidant Properties of Red Raspberries (Rubus idaeus L.) cv. Erika.

In this paper, the effect of the packaging material and storage method on red raspberries produced at Reggio Calabria (Italy) was studied. For this purpose, the fruits were stored immediately after harvest in different conditions: in the fridge at 1 °C and in the freezer at -20 °C, using different packaging materials, two new patented films (nanoactive A) and (nanoactive B), one common packaging film (polyethylene terephthalate), and other fruits were left without any packaging material. Chemical parameters were analysed at harvest to have the initial characteristics without any conditioned storage and to distinguish the post-harvest effect on the fruits, then daily for storage in the fridge and monthly for storage in the freezer. The aims of our project were first to determine the qualitative characterization of these red raspberries, the optimization of their shelf-life during time in the fridge or freezer, using the different types of packaging materials and finally to highlight the usefulness of the new patented packaging materials. Nanoactive A film showed the best shelf-life in the fridge, and after 14 days the values, given as mg/100 g fresh weight, were: total phenolics (166.70), monomeric anthocyanin content (50.82), flavonoids (24.64), ascorbic acid (32.42), and 1, 1-diphenyl-2-picrylhydrazyl (DPPH) assay (95.93).

Phenotypic Plasticity Promotes Overwintering Survival in A Globally Invasive Crop Pest, Drosophila suzukii.

Spotted wing drosophila, Drosophila suzukii Matsumura, is a major pest of small fruit worldwide in temperate and subtropical growing regions. In Northern climates, D. suzukii likely overwinters locally under leaf litter and snow pack, but our understanding of the factors affecting thermal susceptibility is limited. While previous investigations of thermal susceptibility in this species have employed conventional static acclimation protocols, we aimed to determine whether gradual cooling, or dynamic acclimation, may extend the limits of known thermal tolerance by more closely approximating naturally occurring shifts in temperature. First, we assessed survival among adult and pupal D. suzukii using static acclimation. Then, we re-assessed survival using a novel dynamic acclimation method. We found that while static acclimation was sufficient to induce cold tolerance, dynamic acclimation significantly improved survival at temperatures as low as -7.5 °C. Following static acclimation, the lower lethal limit of adult D. suzukii was -1.1 °C in winter morphotype (WM) adults compared to 1.7 °C in non-acclimated summer morphotype (SM) adults. Dynamic acclimation reduced the lower limit to -5 °C in SM flies. At the end of our study 50% of WM flies survived 72 h at -7.5 °C. Below 0 °C pupal survival declined significantly regardless of acclimation procedure. However, pupal acclimation improved survival outcomes significantly compared to non-acclimated pupae, suggesting that while juvenile diapause is unlikely, cold hardening likely benefits those flies which may develop into the overwintering WM population. These data suggest that the degree of cold hardening is proportional to the thermal environment, a finding previously unrecognized in this species. Given the economic impact of this pest, these data may have important implications for offseason population monitoring and management. We discuss how phenotypic plasticity may drive geographical range expansion, and the impact of climate change on the spread of this species.

Interaction between maturity stages and temperature on quality of ‘Guarani’ blackberries stored under controlled atmosphere / Interação entre estádios de maturação e temperatura na qualidade de amora-preta ‘Guarani’ armazenada em atmosfera controlada

ABSTRACT: The aim of this research was to evaluate the interaction between maturity stages and temperature on fruit quality of ‘Guarani’ blackberries stored under controlled atmosphere (CA). The experiment was conducted in a factorial scheme (2x2), evaluating two ripening stages (E1: red-color and E2: black-color of fruits) and two temperatures (1°C and 5°C). The fruit were stored in CA (10.0kPa O2+15.0kPa CO2) and 98±1% of relative humidity (RH). Results showed that the principal component 1 (PC I) and principal component 2 (PC II) corresponded to 92.84% of the overall variation of the evaluated variables. Harvest should not be performed in the early maturity stage, because ‘Guarani’ blackberries do not develop all quality of consumer. ‘Guarani’ blackberries must be stored at 1°C. The maturity stage showed the major importance in the overall variability of quality parameters when compared to storage temperature.

RESUMO: O objetivo deste trabalho foi avaliar a interação entre estádios de maturação e temperatura de armazenamento na qualidade de frutos de amora-preta ‘Guarani’ armazenados em atmosfera controlada (AC). O experimento foi conduzido em esquema fatorial (2x2), avaliando-se dois estádios de maturação (E1: cor vermelha e E2: cor preta dos frutos) e duas temperaturas (1°C e 5°C). Os frutos foram armazenados em AC (10.0kPa O2+15.0Pa CO2) e 98±1% de umidade relativa. Os resultados mostraram que o componente principal 1 (PC I) e o componente principal 2 (PC II) responderam por 92,84% de variação das variáveis analisadas. Conclui-se que a colheita não deve ser realizada em estádio de maturação antecipado, pois a amora-preta ‘Guarani’ não desenvolve todas as características de qualidade para o consumidor. A amora-preta ‘Guarani’ deve ser armazenada na temperatura de 1°C. Os estádios de maturação apresentam maior importância na variação dos parâmetros de qualidade quando comparados a temperaturas de armazenamento.

General aspects of physalis cultivation / Aspectos gerais da cultura da physalis

The Physalis peruviana L. is an exotic fruit that belongs to the Solanaceae family with recent production in Brazil. This is presented as an alternative production with nutritional potential and economic value. The cape gooseberry plant has a high added value that can be used from its root to the fruit itself. The roots and leaves are rich in medicinal properties that are used in pharmacology. The fruit is sweet and have good content of vitamins A, C, iron, phosphorus and fiber, often used in making jellies, jams, juices and ice creams. To improve the plant canopy, but also contribute to the quality and appearance of the fruit produced some cultural practices such as staking, training systems, pruning and thinning are used. The aim of this review is to provide technical and scientific data about the culture of physalis.

A Physalis peruviana L. é uma fruta exótica pertencente à família Solanaceae com produção recente no Brasil. Esta se apresenta como uma alternativa de produção com potencial valor nutricional e econômico. A planta da fisalis possui um alto valor agregado, podendo ser utilizada desde sua raiz até o fruto propriamente dito. As raízes e as folhas são ricas em propriedades medicinais que são utilizadas na farmacologia. O fruto é açucarado e com bom conteúdo de vitaminas A, C, ferro, fósforo e fibras, muito utilizado na fabricação de geleias, doces, sucos e sorvetes. Para melhorar o dossel vegetativo da planta, como também contribuir para a qualidade e aparência do fruto produzido, utiliza-se, durante seu cultivo, algumas práticas culturais, como tutoramento, condução, poda e desbrote. O objetivo desta revisão é fornecer dados técnico-científicos sobre a Cultura da Physalis.