Strawberry Leaf Research Articles

Jasmonic and Abscisic Acid Contribute to Metabolism Re-adjustment in Strawberry Leaves under NaCl Stress

ABSTRACT The aim of this research was to evaluate the effect of exogenous jasmonic acid and abscisic acid, at different salinity regimes, on primary and secondary metabolic changes in ʻKurdistanʼ and ʻQueen Elisaʼ strawberry leaves. To this end, strawberry plants were induced by gradual NaCl salinity (10 mmol•L−1) and shock salinity. The plants were sprayed with ABA (40 mmol•L−1) and JA treatments up to 40 mmol•L−1. In both cultivars, salt shock stress significantly enhanced the total antioxidant capacity, though the JA treatment outperformed the ABA treatment. Increasing JA level in the presence of ABA resulted in downswing in total phenolic content (6.42% in ʻKurdistanʼ and 23.13% in ʻQueen Elisaʼ) and antioxidant capacity (12.9% in ʻKurdistanʼ and 17.7% in ʻQueen Elisaʼ) at non-saline conditions. Adding both hormonesresulted in a 20.82% increase in total phenolic content and a 17.86% increase in total antioxidant capacity in ‘Kurdistan’ at gradual salt stress; however, in ʻQueen Elisaʼ, the same treatment resulted in 21.98% increase in total phenol and 11.92% increase in total antioxidant capacity at salt shock. Salt shock induced tyrosine increase and both hormones enhanced asparagine, alanine, histidine, and GABA contents in ʻQueen Elisaʼ. The study reveals that the applation of abscisic acid along with different jasmonic acid concentrations activates the protective mechanism of the strawberry plant against NaCl stress. Further studies are needed to compare the exact salt stress tolerance mechanisms for these cultivars. Abbreviations: JA: Jasmonic acid; ABA: Abscisic Acid; GABA: γ-Aminobutyric acid

Evaluation of Detached Strawberry Leaves for Anthracnose Disease Severity Using Image Analysis and Visual Ratings

Inoculation of detached strawberry leaves with Colletotrichum species may provide an accurate, rapid, nondestructive method of identifying anthracnose-resistant germplasm. The purpose of this study was to statistically compare two methods (visual and image analysis) of evaluating disease severity of strawberry germplasm screened for anthracnose resistance. Detached leaves of 77 susceptible and resistant strawberry clones were inoculated with one Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. and two C. fragariae A. N. Brooks isolates. Anthracnose disease symptoms on each leaf were assessed quantitatively via computer-based image analysis to determine percentage lesion area and qualitatively by two independent raters using a visual disease severity rating scale (0 = no symptoms to 5 = entire leaf dead). The two visual raters’ average disease severity ratings (n = 3413) were in substantial agreement with a weighted Cohen’s kappa coefficient (k) of 0.80 [95% confidence interval (CI) 0.79–0.82]. There was a strong positive correlation between percent lesion area determined by image analysis and the visual disease scores of the two raters (rp = 0.79). Image analysis provided a precise measurement of percent lesion area of infected leaves while visual assessment provided more rapid results. Our results indicate that detached leaf inoculations can be used as a rapid preliminary screen to separate anthracnose-susceptible from -resistant germplasm in large populations within breeding programs. It also may be used for assessing the resistance/susceptibility of parental breeding lines to various Colletotrichum species and isolates, for mapping germplasm for resistance genes, and in pesticide development studies.

Evaluation of advanced selections of strawberry in southern Brazil

Strawberry cultivation is technically considered a complex activity, which demands high inputs in investment and manpower. One of the most relevant technical aspects of this crop is the choice of correct cultivars. A highly fea­sible way to obtain fully adapted genotypes with high production potential and fruit quality is to select the geno­types with best performance in the producing region itself. The objective of this work was to evaluate the ad­vanced selections of strawberry on productive performance, fruit quality and resistance to strawberry leaf spot, powdery mildew and anthracnose, under conditions of the municipality of Lages, Santa Catarina State. Eleven genotypes were evaluated, being one commercial cultivar - San Andreas - and ten advanced selections, namely: ITA 12,103-15; ITA 12,103-12; ITA 12,103-22; ITA 10,107-6; ITA 10,107-7; ITA 13,097-05; ITA 10,133-2; ITA 10,128-9; ITA 12,103-6 and ITA 10,107-12. The experimental design was in randomized blocks, with three repli­cations, and plots constituted by eleven plants. The cultivar San Andreas presented the best results for total (657.06 g plant -1 ) and commercial production (547.77 g plant -1 ), and number of commercial fruits per plant (30.81 fruits plant -1 ). The selections ITA 10,128-9; ITA 10,133-2; ITA 13,097-5; ITA 10,107-7 and ITA 10,107-12 obtained the highest values for soluble solids content, above to 8.5 °Brix, being superior than San Andreas cultivar for this variable. The genotypes ITA 12,103-15 and ITA 10,107-12, on the other hand, were the most resistant to the dis­eases evaluated.

Genetic variation in herbivore resistance within a strawberry crop wild relative (Fragaria vesca L.)

To decrease the dependency on chemical pesticides, the resistance of cultivated strawberry to pests needs to be increased. While genetic resources within domesticated varieties are limited, wild genotypes are predicted to show high heritable variation in useful resistance traits. We collected 86 wild accessions of Fragaria vesca L. from central Sweden and screened this germplasm for antibiosis (pest survival and performance) and antixenosis (pest preference) traits active against the strawberry leaf beetle (Galerucella tenella L.). First, extensive common garden experiments were used to study antibiosis traits in the sampled plant genotypes. Heritable genetic variation among plant genotypes was found for several antibiosis traits. Second, controlled cafeteria experiments were used to test for plant genetic variation in antixenosis traits. The leaf beetles avoided egg laying on plant genotypes possessing high antibiosis. This indicates a high degree of concordance between antibiosis and antixenosis and that the beetles’ egg-laying behavior optimizes the fitness of their offspring. The existence of high genetic variation in key resistance traits suggests that wild woodland strawberry contains untapped resources that are sought to reduce pesticide dependence in cultivated strawberry. Given that only a very small portion of the species’ distribution area was sampled, even higher variation may be expected at the continental scale. As a whole, the genetic resources identified in this study serve to strengthen the position of woodland strawberry as a key crop wild relative.

Reinvigoration of diploid strawberry (Fragaria vesca) during adventitious shoot regeneration

Diploid strawberry (Fragaria vesca ‘Baiguo’) is a model plant for studying functional genomics in Rosaceae. Adventitious shoot regeneration is essential for functional genomics by Agrobacterium tumefaciens-mediated transformation. An efficient shoot regeneration method using diploid strawberry leaf explants was conducted on 1/2MS + 1/2B5 medium that contained 2.0 mg L−1 TDZ over 14 days of dark culture; this induced the maximum percentage of shoot regeneration (96.44 ± 1.60%) and the highest number of shoots per explant (23.46 ± 2.14) after 11 weeks of culture. The explants considerably enlarged after 12 days; then, turned greenish brown after 30 days, yellowish brown after 36 days, and completely brown and necrotic after 48 days. Large numbers of adventitious shoots were produced from 48 to 66 days, and the shoots elongated from 66 to 78 days; this represents a critical period of reinvigoration, which included 30 days for leaf explant chlorosis, 36 days for adventitious shoot appearance, and 48 days for generation of numerous shoots. During the reinvigoration process, higher expressions of the hormone synthesis-related genes Ciszog1, CKX2, CKX3, CKX7, YUC2, YUC6, YUC10, YUC9, and GA2ox were detected from 30 to 48 days. Our results indicate that these genes may regulate reinvigoration of shoot regeneration.

Pest categorisation of non-EU viruses of Fragaria L.

Following a request from the EU Commission, the Panel on Plant Health addressed the pest categorisation of the viruses and viroids of Fragaria L. determined as being either non‐EU or of undetermined standing in a previous EFSA opinion. These infectious agents belong to different genera and are heterogeneous in their biology. With the exclusion of strawberry latent virus and strawberry latent C virus for which very limited information exists, the pest categorisation was completed for 12 viruses having acknowledged identities and available detection methods. All these viruses are efficiently transmitted by vegetative propagation techniques, with plants for planting representing the major pathway for long‐distance dispersal and thus considered as the major pathway for entry. Depending on the virus, additional pathway(s) can also be Fragaria seeds, pollen and/or vector(s). Most of the viruses categorised here are known to infect only one or few plant genera, but some of them have a wide host range, thus extending the possible entry pathways. Strawberry chlorotic fleck‐associated virus, strawberry leaf curl virus, strawberry necrotic shock virus, strawberry pallidosis‐associated virus, strawberry vein banding virus (SVBV) and tomato ringspot virus meet all the criteria evaluated by EFSA to qualify as potential Union quarantine pests (QPs). For SVBV, the Panel considered that following its entry and establishment into the EU territory, an impact of uncertain magnitude is expected mainly because a synergistic effect may occur in strawberry in case of mixed infections with viruses already present in the EU . Strawberry crinivirus 3, strawberry crinivirus 4 and strawberry polerovirus 1 meet all criteria for being considered as potential Union QPs, except for the impact in the EU territory, on which the Panel was unable to conclude. Fragaria chiloensis cryptic virus, Fragaria chiloensis latent virus and strawberry pseudo mild yellow edge virus do not meet the criterion of having potential negative impact in the EU. For several viruses, especially those recently discovered, the categorisation is associated with high uncertainties mainly because of the absence of data on their biology, distribution and impact. Since this opinion addresses specifically the non‐EU viruses, in general, these viruses do not meet the criteria assessed by EFSA to qualify as potential Union regulated non‐quarantine pests.

Electrophysiological and Behavioral Responses of Drosophila suzukii (Diptera: Drosophilidae) Towards the Leaf Volatile β-cyclocitral and Selected Fruit-Ripening Volatiles.

The spotted-wing drosophila, Drosophila suzukii Matsumura (Diptera: Drosophilidae), is attracted to numerous volatile organic compounds (VOCs) emitted from several ripening, small fruit crops. However, the strawberry leaf terpenoid, β-cyclocitral, is reportedly very attractive to D. suzukii (but not to all Drosophila spp.). This suggests that leaf and fruit VOCs may be critical sources needed to further develop a more species-specific D. suzukii monitoring lure, or semiochemically based attract-and-kill systems. This study investigated the electrophysiological responses of male and female D. suzukii towards selected host fruit-ripening VOCs and β-cyclocitral, along with behavioral responses toward combined fruit VOCs with β-cyclocitral. Electroantennogram (EAG) results revealed a positive dose-response, for both sexes, as concentrations increased for all VOCs tested. For β-cyclocitral, hexyl acetate and methyl butyrate, the mean male EAG responses were significantly greater than the female responses at lower doses. In caged behavioral bioassays, only in the β-cyclocitral treatments were the mean number of flies captured (sexes combined) significantly greater than that captured in solvent (mineral oil) controls. Our study has demonstrated that while single fruit-based VOCs alone are not enough to cause a strong behavioral attraction by both male and female D. suzukii, the addition of β-cyclocitral did produce a significant attraction response from both sexes. In both bioassays, males had higher responses to β-cyclocitral than females, which suggest a greater sensitivity to this compound. Further studies are needed to ascertain the role β-cyclocitral may play in the development of a more species-specific D. suzukii monitoring lure.

Extraction of strawberry leaves with supercritical carbon dioxide and entrainers: Antioxidant capacity, total phenolic content, and inhibitory effect on uric acid production of the extract

The recovery of useful components such as antioxidants from strawberry leaves would be desirable because this byproduct is usually disposed of as agricultural waste. In this study, strawberry leaves were extracted with supercritical carbon dioxide (sc-CO2) and the effects of various entrainers were evaluated under the following conditions: temperature from 308 to 333K, pressure from 15 to 30MPa, and a molar ratio of entrainer to CO2 of 0.1. The use of ethanol, acetone, and water improved the extraction yield, antioxidant capacity and total phenolic content of the extract. In sc-CO2+ethanol, the antioxidant capacity and total phenolic content exhibited maximum values for a given temperature at 20MPa. The antioxidant capacity was almost independent of pressure and total phenolic content had a maximum at 308K. The solvent density, solubility of organics, and vapor pressure of compounds appeared to influence the antioxidant capacity and total phenolic content. Furthermore, the strawberry leaf extract obtained using sc-CO2+ethanol significantly and dose-dependently suppressed uric acid production in cultured hepatocytes.

Effect of Different Hormone Applications on Antioxidant Enzyme Activities of Strawberry Leaves

Bu çalışma, 5 farklı çilek çeşidinde (Albion, Aromas, Honeoye, Seascape, Sweet Ann) dışardan metil jasmonat (MeJA) ve gibberalik asit (GA3) uygulamasının antioksidan enzim aktiviteleri üzerine etkisini belirlemek amacıyla yapılmıştır. 50ppm ve 100ppm dozlarında GA3 ve 0.25, 0.50 ve 1.00 mM dozlarında MeJA uygulaması yapraktan uygulanmıştır. Alınan yaprak örneklerinde katalaz (KAT), süperoksidaz dismutaz (SOD) ve malondialdehit (MDA) miktarları okunmuştur. Sweet Ann çeşidi en yüksek KAT ve SOD aktivitesine sahipken, Honeoye çeşidi en düşük değerlere sahip olmuştur. CAT aktivitesi Seascape ve Aromas çeşitlerinde azalma göstermiş diğer çeşitlerde uygulama ve doza bağlı olarak değişkenlik görülmüştür. SOD miktarı Albion ve Seascape çeşitlerinde her uygulama ile artış kaydetmiştir. KAT ve SOD aktivitesinin aksine, MDA konsantrasyonu en fazla Honeoye çeşidinde, en düşük Sweet Ann çeşidinde belirlenmiştir. Yapılan araştırmada, GA3 ve MeJa uygulamaları çilek çeşitlerine ve uygulanma dozlarına bağlı olarak yaprakların enzim ve MDA içeriklerini etkilediği saptanmıştır.

Huella genética de variedades de fresa obtenidas en el Colegio de Postgraduados, México

En un programa de mejoramiento genético de fresa (Fragaria × ananassa) es importante contar con la metodología para evaluar la integridad genética de la planta en todas las etapas de incremento, desde diferentes criterios, como el fisiológico, morfológico y el molecular; para este propósito, una de las herramientas más apropiadas son los marcadores moleculares denominados Secuencias Simples Repetidas del inglés Simple Sequence Repeats (SSR), ya que permiten, por ejemplo, identificar poblaciones con una diversidad genética reducida, revelar genealogías, conocer el grado de parentesco entre individuos, proporcionar elementos sólidos en la defensa de la propiedad intelectual, evaluar la pureza del material vegetal, identificar el grado de variación somaclonal y evitar la mezcla de material vegetal en bancos de germoplasma. En este sentido, el presente estudio tuvo como objetivo obtener la huella genética de las variedades de fresa CP0201, CP0204, CP0615, CPLE7 desarrolladas en el Colegio de Postgraduados y como testigo la variedad Festival, desarrollada en Florida, USA, con el uso de nueve loci de microsatélites (SSR). El proceso incluyó la extracción de ADN a partir de tejido foliar de fresa, así como de la amplificación mediante PCR de punto final de los loci SSR agrupados en reacciones multiplex. Los productos de PCR fueron separados mediante electroforesis capilar y su tamaño en pares de bases se determinó con el programa GeneMapper® v. 4. A partir de las frecuencias alélicas se calcularon las matrices de distancia con los coeficientes de Jaccard y Dice. Se encontraron 63 alelos distintos, cada par de iniciadores amplificó entre 3 y 12 alelos. Los marcadores que presentaron mayor número de alelos fueron EMFn181 (11 alelos) y EMFv104 (12 alelos). Se generó la huella genética de cada variedad. Mediante los perfiles alélicos se encontraron diferencias entre las variedades CP0615, CPLE7 y Festival; CP0201 y CP0204 tuvieron una huella genética similar, ya que están emparentadas a través de su progenitor femenino; el índice de diversidad alélica dentro de las poblaciones varió de 3.96 a 5.93. Las variedades tuvieron un índice de uniformidad bajo debido al alto nivel de polimorfismo de los marcadores usados.

Development of an artificial cloud lighting condition system using machine vision for strawberry powdery mildew disease detection

Strawberry plants have been facing a significant proportion of diseases during cultivation, scattered throughout the field, emphasizing the need for proper diseases management. Powdery mildew is one of the major fungal strawberry disease which is typically responsible for approximately 30–70% loss of yields. The aim of this study was to develop a machine vision based artificial cloud lighting condition system for detecting strawberry powdery mildew leaf disease. The artificial cloud lighting condition system was developed consisting of custom software, two µEye colour cameras, a black cloth cover, real time kinematics-global positioning system and a ruggedized laptop computer and mounted on a mobile platform. The custom software was developed in C# programming language. The colour co-occurrence matrix based texture analysis was used to extract image features and discriminant analysis (quadratic) for classification. The study proposed mobile platform of artificial cloud lighting condition for image acquisition is beneficial. It showed higher detection accuracies of 95.26%, 95.45% and 95.37% for recall, precision and F-measure, respectively compared to 81.54%, 72% and 75.95% of recall, precision and F-measure, respectively with acquired images at natural cloud lighting condition. The feature selection results suggested the PM_GHSI feature model was best fit for this study. This study also revealed that the image acquisition speed (1.5 km h−1) and working depth (300 mm) are suitable for strawberry powdery mildew disease detection in real-time field condition.

Inheritance of Resistance to Colletotrichum gloeosporioides and C. acutatum in Strawberry.

Information on the inheritance of resistance to Colletotrichum gloeosporioides and C. acutatum hemibiotrophic infections (HBI) in strawberry leaf tissue and the genetic control of anthracnose crown rot (ACR) in crown tissue are relatively unknown. Six parental genotypes were crossed in a half-diallel mating design to generate 15 full-sib families. HBI and ACR experiments were conducted concurrently. Both seedlings and parental clones were inoculated with 1 × 106 conidia/ml of C. gloeosporioides or C. acutatum. Percent sporulating leaf area, wilt symptoms, and relative area under the disease progress curve were calculated to characterize resistance among genotypes and full-sib families. Low dominance/additive variance ratios for C. acutatum HBI (0.13) and C. gloeosporioides ACR (0.20) were observed, indicating additive genetic control of resistance to these traits. Heritability estimates were low for C. acutatum HBI (0.25) and C. gloeosporioides HBI (0.16) but moderate for C. gloeosporioides ACR (0.61). A high genetic correlation (rA = 0.98) between resistance to C. acutatum HBI and C. gloeosporioides HBI was observed, suggesting that resistance to these two Colletotrichum spp. may be controlled by common genes in strawberry leaf tissue. In contrast, negative genetic correlations between ACR and both HBI traits (rA = -0.85 and -0.61) suggest that resistance in crown tissue is inherited independently of resistance in leaf tissue in the populations tested. Overall, these findings provide valuable insight into the genetic basis of resistance, and the evaluation and deployment of resistance to HBIs and ACR in strawberry breeding programs.

Management of strawberry leaf blight disease caused by Phomopsis obscurans using silicate salts under field conditions

BackgroundDue to the increased economic and social benefits of the strawberry crop yield in Egypt, more attention has been paid to control its pests and diseases. Leaf blight, caused by the fungus Phomopsis obscurans, is one of the important diseases of strawberry plants. Therefore, effect of silicon and potassium, sodium and calcium silicates, and a fungicide on Phomopsis leaf blight of strawberry under laboratory and field conditions was examined.ResultsFour concentrations, i.e., 0, 2, 4, and 6 g/l of silicon as well as potassium, sodium and calcium silicates could significantly reduce the linear growth of tested fungus in the laboratory test where complete inhibition of linear growth was obtained with 6 g/l. The other concentrations showed less but favorable effects. The highest reduction of disease severity was obtained with potassium silicate and calcium silicate separately applied as soil treatment combined with foliar spray which reduced the disease incidence by 83.3 and 86.7%, respectively. Other treatments showed significant (P ≤ 0.05) but less effect. The highest yield increase was obtained with potassium silicate and calcium silicate applied as soil treatment combined with foliar spray which increased fruit yield by 60 and 53.8%, respectively. All tested treatments increased (P ≤ 0.05) the activities of the peroxidase, polyphenol oxidase, and chitinase enzymes.ConclusionsAll tested concentrations of silicon salts have suppressed the fungal growth and disease spread but with different degrees. The more the concentration, the better it suppresses the fungal growth and consequent effect on damaging strawberry plants. Potassium silicate and calcium silicate separately applied as soil treatment combined with foliar spray were the best in reducing the disease incidence and increasing crop yield. Potential implications of silicate salts on enhancing activities of the tested enzymes reflected their role in protection against such a plant disease.

Chemopreventive and Anti-Inflammatory Potential of Select Herbal Teas and Cinnamon in an <i>In-Vitro</i> Cell Model

Colon cancer is the third leading cause of death in the US. Herbal teas and spices may reduce the incidence of chronic diseases, including colon cancer. The objectives of this study were to determine the chemopreventive effects of herbal teas and cinnamon in an in-vitro cell model and to evaluate the inhibitory effects of selected extracts on enzymes associated with inflammatory disease. Effects of raspberry leaf (0.5 - 2.0 mg/mL), strawberry leaf (0.4 - 1.0 mg/mL), hibiscus flower (4.0 - 10.0 mg/mL) and cinnamon (400 - 1500 μg/mL) were evaluated for cytotoxicity, induction of caspase and DNA fragmentation in colon cancer (Caco-2) cells to determine possible chemopreventive effects. Effects of extracts on inhibition of cyclooxygenase-2 (COX-2) were also measured to determine possible anti-inflammatory potential. Caco-2 cells were obtained from American Type Culture Collection (ATCC) and maintained in Dulbecco’s Modified Eagle’s Medium with 10% fetal bovine serum. As concentrations of tea increased, LDH release from Caco-2 cells increased, with cytotoxicity ranging from 1% - 80% (hibiscus flower 1.0 mg/mL and strawberry leaf (1.0 mg/mL) for teas. All extract concentrations of herbal teas and cinnamon were able to enhance caspase-3 activity with lowest activity (4.4 mmol/ min/mL) observed in the lowest concentration of cinnamon (400 μg/mL) and highest activity (6.0 mmol/min/mL) seen in the highest concentration of raspberry leaf (2 mg/mL). Tea and spice extracts were able to induce apoptosis in Caco-2 cells exhibited by increased DNA fragmentation (expressed as enrichment factor). Enrichment factor ranged from 1.0 - 1.5 (raspberry leaf 1.0 mg/mL and hibiscus 10.0 mg/mL). Teas and cinnamon exhibited anti-inflammatory potential by inhibiting COX-2 by 0.6% - 8.0% (raspberry leaf 1.0 mg/mL and strawberry leaf 0.8 mg/mL). The results suggest that herbal teas and cinnamon may have significant benefits in chemoprevention.

Strawberry (Fragaria x ananassa) leaf extract reduces brain damage in diabetic rats

Brain damage is one of the consequences of diabetes. The main cause of this damage is the overproduction of free radicals resulted from hyperglycemia. Hence came the idea of research in testing the effect of administration of strawberry leaf extract as an antioxidant to reduce brain damage in diabetic rats. Five groups of rats were divided into control rats group, diabetic rats group, and three diabetic rat groups treated with strawberry leaf extract (50, 100 and 200 mg/ kg body weight) for 30 days. Diabetic rat brains showed significant increases in malondialdehyde (MDA), tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6 and caspase-3 and significant decreases in catalase (CAT), superoxide dismutase (SOD), and vascular endothelial growth factor (VEGF)-A. Plasma dopamine and melatonin levels were decreased significantly in diabetic rats. After treating the diabetic rats with the three different doses of strawberry leaf extract, the brain and plasma biochemical parameters improved significantly. The study showed the utility of using the strawberry leaf extract as an antioxidant, anti-inflammatory, and anti-apoptosis to improve brain damage caused by diabetes.

Bio-Boron Fertilizer Applications Affect Amino Acid and Organic Acid Content and Physiological Properties of Strawberry Plant

The effects of boron and plant growth promoting bacteria (Bio-B) on the some of physiological parameters with amino acid and organic acid of strawberry cv. Fern were investigated under field conditions. The study treatments were soil, foliar, and soil + foliar applications as main plot and two Bio-B (control and plant growth promoting rhizobacteria; Azospirillum brasilense 1 × 109 cfu ml−1 + 10% boron as Di-SodyumOktaboratTetraHidrat) fertilizer applications as subplot in complete randomized block design with four replicates. Bio-B fertilizer was applied in three methods such as soil, foliar and soil + foliar application methods on strawberry. Two years data from the present study reported that the use of Bio-B significantly increased chlorophyll, photosynthesis, stomatal and membrane permeability, amino acid and organic acid of strawberry leaf. Soil + foliar applications of Bio-B fertilizer increased to strawberry yield compared to the control by 65.9%. Foliar applications of Bio-B fertilizer increased chlorophyll and stomatal permeability in comparison to the control by 17.62 and 56.52%, respectively. However, soil + foliar application of Bio-B fertilizer increased membrane permeability and photosynthesis compare to those under the control 24.80 and 23.32%, respectively. Amino acid content of strawberry was increased (23.45%) and organic acid amount was increased (23.45%) under soil application of Bio-B fertilizer compare to those under the control. The results of this study concluded that Bio-B fertilizer application was positively associated with strawberry yield and increased the potential to chlorophyll, photosynthesis, stomatal and membrane permeability, amino acid, organic acid content under field conditions.

Folivory has long-term effects on sexual but not on asexual reproduction in woodland strawberry.

Plant fitness is often a result of both sexual and asexual reproductive success and, in perennial plants, over several years. Folivory can affect both modes of reproduction. However, little is known about the effects of folivory on resource allocation to the two modes of reproduction simultaneously and across years. In a 2‐year common garden experiment, we examined the effects of different levels of folivory by the strawberry leaf beetle, Galerucella tenella, on current growth, as well as current and future sexual and asexual reproduction (runners) of perennial woodland strawberry, Fragaria vesca. In addition, we measured the chlorophyll content in leaves in the year of experimental damage to determine whether there was increased photosynthetic activity, and, thus, a compensatory response to herbivory. Finally, we tested whether the previous year's folivory, as a result of its effect on plant fitness, affected the level of natural herbivory the plant experienced during the subsequent year. In the year of experimental damage, plants that were exposed to moderate and high levels of folivory (25% and 50% leaf area consumed, respectively) increased their photosynthetic activity compared to control plants. However, only plants exposed to high folivory exhibited negative effects, with a lower probability of flowering compared to control plants, indicating that plants exposed to low or moderate folivory were able to compensate for the damage. Negative effects of folivory were carried over to the subsequent year. Plants that were exposed to moderate folivory (25% leaf area consumed) during first year produced fewer flowers and fruits in the subsequent year. Runner production was consistently unaffected by folivory. The effects of experimental folivory on the level of natural herbivory were mediated via its effects on plant fitness. Our results show that the negative effects of folivory only influence sexual reproduction in woodland strawberry. Furthermore, even though woodland strawberry can tolerate moderate amounts of folivory in the short term, the negative effects on fitness appear later; this highlights the importance of studying the effects of herbivory over consecutive years in perennial plants.

The effects of strawberry tree (Arbutus unedo L.) water leaf extract and arbutin upon kidney function and primary DNA damage in renal cells of rats

Although strawberry tree (Arbutus unedo L.) leaves have long been used as a herbal remedy, insufficient information is available on their nephrotoxicity. We assessed the safety of strawberry tree water leaf extract and its key component arbutin, administered per os to Lewis rats of both genders at 200 mg/kg b.w./day for 14 and 28 days. The effects of the tested compounds on DNA integrity in renal cells was evaluated using alkaline comet assay, while kidney function was studied using serum creatinine and urea levels. Strawberry tree water leaf extract showed high biocompatibility with kidney tissue. It did not impair DNA integrity of renal cells and kidney function, either in male or female rats. However, exposure to single arbutin affected the levels of primary DNA damage in renal cells which could be related to metabolic conversion of arbutin into hydroquinone, whose nephrotoxicity has previously been proven.

Interrelation of plant nutrients of strawberry leaf samples under Mediterranean climate condition

The study was conducted in the Mediterranean part of Turkey, on the commercial important strawberry cultivars grown under Spanish type high tunnels during 2015-2016. Macro and micro plant nutrients of 180 leaf samples, were analysed in the intense growing period at monthly intervals and determined by standard methods. The interrelation of plant nutrition was evaluated using the Pearson correlation coefficient with 5% significant level. According to our findings, the calcium nutrition was significantly positive correlated with magnesium and potassium (p<0.01). Except for this correlation, no relation was found between nitrogen and phosphorus, while zinc and copper were positively correlated. They decreased with increasing of the N and Mg content, that being structure of chlorophyll in the strawberry leaves. Moreover, the iron and manganese concentrations were positively correlated. This study reflects the interrelation among plant nutrients used for important physiological processes. Thus, plant growing may be better controlled with management of suitable fertilization.

Concentration and periods of application of prohexadione calcium in the growth of strawberry seedlings

For strawberry cultivation in Brazil, producers are dependent on imported seedlings. An alternative strategy to reduce this dependence is the use of seedlings obtained from nursery plants grown in a protected environment. However, as these seedlings are produced in the summer and planted at the end of this season or the spring of the following year, it is necessary to control growth to reduce the energy costs of the plants. The objective of this study was to evaluate the effect of different concentrations and periods of application of proexadione calcium (ProCa) on growth control of strawberry seedlings. The experiment was carried out in a greenhouse with seedlings of the cultivars ‘Aromas’ and ‘Camarosa’, produced by rooting stolons and kept in polystyrene trays of 72 cells in a substrate of carbonized rice husk. The experimental design was completely randomized, with a 4 × 2 factorial scheme (4 concentrations of ProCa: 0, 100, 200, and 400 mg L-1 × 2 periods of application: at 20 and 30 days after the planting period of rooting stolon). Plant survival, crown diameter, petiole length, total leaf area, specific leaf area, chlorophyll concentration, and dry mass of the crown and shoot were evaluated. The application of ProCa at 20 days after the planting period of the rooting stolon at the concentrations of 200 and 400 mg L-1 favored the reduction of petiole length in plants of ‘Aromas’ strawberry and total leaf aerial in ‘Camarosa’ strawberry. The application of ProCa from the concentration of 100 mg L-1 reduced the vegetative growth of ‘Aromas’ and ‘Camarosa’ strawberry seedlings cultivated in substrate.