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Ecological and Genetic Differences between Cacopsylla melanoneura (Hemiptera, Psyllidae) Populations Reveal Species Host Plant Preference  [PDF]
Valeria Malagnini, Federico Pedrazzoli, Chiara Papetti, Christian Cainelli, Rosaly Zasso, Valeria Gualandri, Alberto Pozzebon, Claudio Ioriatti
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0069663
Abstract: The psyllid Cacopsylla melanoneura is considered one of the vectors of ‘Candidatus Phytoplasma mali’, the causal agent of apple proliferation disease. In Northern Italy, overwintered C. melanoneura adults reach apple and hawthorn around the end of January. Nymph development takes place between March and the end of April. The new generation adults migrate onto conifers around mid-June and come back to the host plant species after overwintering. In this study we investigated behavioural differences, genetic differentiation and gene flow between samples of C. melanoneura collected from the two different host plants. Further analyses were performed on some samples collected from conifers. To assess the ecological differences, host-switching experiments were conducted on C. melanoneura samples collected from apple and hawthorn. Furthermore, the genetic structure of the samples was studied by genotyping microsatellite markers. The examined C. melanoneura samples performed better on their native host plant species. This was verified in terms of oviposition and development of the offspring. Data resulting from microsatellite analysis indicated a low, but statistically significant difference between collected-from-apple and hawthorn samples. In conclusion, both ecological and genetic results indicate a differentiation between C. melanoneura samples associated with the two host plants.
Cacopsylla picta (costalis Flor, 1861) (F rster, 1848) (Homoptera, Psyllidae) a New Jumping Plant Louse Species on Apples in Serbia
Du?anka Jerini?-Prodanovi?
Pesticidi i Fitomedicina , 2007,
Abstract: Until recently only one jumping plant louse species Cacopsylla mali Schm. has been described on apples in domestic literature. Over the past few years investigations of Psylloidea on apples in Serbia have proved incidences of another two species, namely C. melanoneuraF rster and C. picta (costalis) F rster. The aim was to describe the basic morphological characteristics of the newly identified jumping plant louse C. picta on apples in Serbia, its distribution and development cycle.
Molecular Test to Assign Individuals within the Cacopsylla pruni Complex  [PDF]
Jean Peccoud, Gérard Labonne, Nicolas Sauvion
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0072454
Abstract: Crop protection requires the accurate identification of disease vectors, a task that can be made difficult when these vectors encompass cryptic species. Here we developed a rapid molecular diagnostic test to identify individuals of Cacopsylla pruni (Scopoli, 1763) (Hemiptera: Psyllidae), the main vector of the European stone fruit yellows phytoplasma. This psyllid encompasses two highly divergent genetic groups that are morphologically similar and that are characterized by genotyping several microsatellite markers, a costly and time-consuming protocol. With the aim of developing species-specific PCR primers, we sequenced the Internal Transcribed Spacer 2 (ITS2) on a collection of C. pruni samples from France and other European countries. ITS2 sequences showed that the two genetic groups represent two highly divergent clades. This enabled us to develop specific primers for the assignment of individuals to either genetic group in a single PCR, based on ITS2 amplicon size. All previously assigned individuals yielded bands of expected sizes, and the PCR proved efficient on a larger sample of 799 individuals. Because none appeared heterozygous at the ITS2 locus (i.e., none produced two bands), we inferred that the genetic groups of C. pruni, whose distribution is partly sympatric, constitute biological species that have not exchanged genes for an extended period of time. Other psyllid species (Cacopsylla, Psylla, Triozidae and Aphalaridae) failed to yield any amplicon. These primers are therefore unlikely to produce false positives and allow rapid assignment of C. pruni individuals to either cryptic species.
Immunomodulatory effect of Hawthorn extract in an experimental stroke model
Chinnasamy Elango, Sivasithambaram Devaraj
Journal of Neuroinflammation , 2010, DOI: 10.1186/1742-2094-7-97
Abstract: After 15 days of treatment with Hawthorn extract [100 mg/kg, pretreatment (oral)], male Sprague Dawley rats underwent transient MCAO for 75 mins followed by reperfusion (either 3 or 24 hrs). We measured pro-inflammatory cytokines (IL-1β, TNF-α, IL-6), ICAM-1, IL-10 and pSTAT-3 expression in the brain by appropriate methods. We also looked at the cytotoxic T cell sub-population among leukocytes (FACS) and inflammatory cell activation and recruitment in brain (using a myeloperoxidase activity assay) after ischemia and reperfusion (I/R). Apoptosis (TUNEL), and Bcl-xL- and Foxp3- (Treg marker) positive cells in the ipsilateral hemisphere of the brain were analyzed separately using immunofluorescence.Our results indicate that occlusion followed by 3 hrs of reperfusion increased pro-inflammatory cytokine and ICAM-1 gene expressions in the ipsilateral hemisphere, and that Hawthorn pre-treatment significantly (p ≤ 0.01) lowered these levels. Furthermore, such pre-treatment was able to increase IL-10 levels and Foxp3-positive cells in brain after 24 hrs of reperfusion. The increase in cytotoxic T cell population in vehicle rats after 24 hrs of reperfusion was decreased by at least 40% with Hawthorn pretreatment. In addition, there was a decrease in inflammatory cell activation and infiltration in pretreated brain. Hawthorn pretreatment elevated pSTAT-3 levels in brain after I/R. We also observed an increase in Bcl-xL-positive cells, which in turn may have influenced the reduction in TUNEL-positive cells compared to vehicle-treated brain.In summary, Hawthorn extract helped alleviate pro-inflammatory immune responses associated with I/R-induced injury, boosted IL-10 levels, and increased Foxp3-positive Tregs in the brain, which may have aided in suppression of activated inflammatory cells. Such treatment also minimizes apoptotic cell death by influencing STAT-3 phosphorylation and Bcl-xL expression in the brain. Taken together, the immunomodulatory effect of Hawthorn extract m
Polyphenolic Profile and Biological Activity of Chinese Hawthorn (Crataegus pinnatifida BUNGE) Fruits  [PDF]
Tunde Jurikova,Jiri Sochor,Otakar Rop,Jiri Mlcek,Stefan Balla,Ladislav Szekeres,Vojtech Adam,Rene Kizek
Molecules , 2012, DOI: 10.3390/molecules171214490
Abstract: Chinese hawthorn (Crataegus pinnatifida Bge.) fruits are rich in polyphenols (e.g., epicatechin, procyanidin B2, procyanidin B5, procyanidin C1, hyperoside, isoquercitrin and chlorogenic acid)—active compounds that exert beneficial effects. This review summarizes all information available on polyphenolic content and methods for their quantification in Chinese hawthorn berries and the relationships between individual polyphenolic compounds as well. The influence of species or cultivars, the locality of cultivation, the stage of maturity, and extract preparation conditions on the polyphenolic content were discussed as well. Currently, only fruits of C. pinnatifida and C. pinnatifida var. major are included in the Chinese Pharmacopoeia. Recent trials have demonstrated the efficacy of Chinese hawthorn fruit in lowering blood cholesterol and the risk of cardiovascular diseases. The fruit has also demonstrated anti-inflammatory and anti-tumour activities. This review deals mainly with the biological activity of the fruit related to its antioxidant properties.
Triterpenic Acids Present in Hawthorn Lower Plasma Cholesterol by Inhibiting Intestinal ACAT Activity in Hamsters
Yuguang Lin,Mario A. Vermeer,Elke A. Trautwein
Evidence-Based Complementary and Alternative Medicine , 2011, DOI: 10.1093/ecam/nep007
Abstract: Hawthorn (Crataegus pinnatifida) is an edible fruit used in traditional Chinese medicine to lower plasma lipids. This study explored lipid-lowering compounds and underlying mechanisms of action of hawthorn. Hawthorn powder extracts inhibited acylCoA:cholesterol acyltransferase (ACAT) activity in Caco-2 cells. The inhibitory activity was positively associated with triterpenic acid (i.e., oleanolic acid (OA) and ursolic acid (UA)) contents in the extracts. Cholesterol lowering effects of hawthorn and its potential additive effect in combination with plant sterol esters (PSE) were further studied in hamsters. Animals were fed a semi-synthetic diet containing 0.08% (w/w) cholesterol (control) or the same diet supplemented with (i) 0.37% hawthorn dichloromethane extract, (ii) 0.24% PSE, (iii) hawthorn dichloromethane extract (0.37%) plus PSE (0.24%) or (iv) OA/UA mixture (0.01%) for 4 weeks. Compared to the control diet, hawthorn, PSE, hawthorn plus PSE and OA/UA significantly lowered plasma non-HDL (VLDL
Responses of potato cultivars to the psyllid (Bactericera cockerelli) under greenhouse conditions
Díaz-Valasis, Margarita;Cadena-Hinojosa, Mateo Armando;Rojas Martínez, Reyna Isabel;Zavaleta-Mejía, Emma;Ochoa Martínez, Daniel;Bujanos Mu?iz, Rafael;
Agricultura técnica en México , 2008,
Abstract: the responses of 20 potato cultivars to the psyllid bactericera cockerelli (= paratrioza cockerelli) were studied under greenhouse conditions. two different trials were conducted, in one two months after planting, 200 adult insects, taken from a phytoplasms-free psyllid colony checked by pcr technique, were released inside a cage in which the potato plants were growing. no insects were placed in a control cage. at the end of the growth cycle following traits were recorded: number of nymphs plant-1, tuber yield (g plant-1) and number of tubers plant-1, also records were made of the degree of internal tuber browning and any abnormal tuber sprouting. in a second trial, psyllid yellows and its capacity to be transmitted in tubers and through grafts were studied in two susceptible cultivars. in the first trial all genotypes showed typical yellowing symptoms on foliage after 15-20 days of exposure to the insect. the number of nymphs among cultivars varied from 90 to 450 plant-1 in 2004 and from 490 to 1800 in 2005. cultivars alpha, gigant, nau-6 and lady rosetta were tolerant since they showed from none to mild internal tuber browning caused by the psyllid. in the rest of the cultivars, discoloration varied from moderate to strong. secondary tuber transmission and serial transmission of psyllid yellows by grafting were not observed; neither foliar symptoms nor internal browning were detected, and sprouting was normal. in both years, yield and number of tubers were significantly reduced by b. cockerelli in all cultivars. internal browning, premature sprouting, lack of sprouting, and hairy sprouts were all induced by the psyllid under greenhouse conditions in the absence of the phytoplasms associated with purple top disease.
Occurence and biological aspects of the clitoria tree psyllid in Brazil
Gondim Junior, Manoel Guedes Corrêa;Barros, Reginaldo;Silva, Fernando Rodrigues da;Vasconcelos, Geraldo José Nascimento de;
Scientia Agricola , 2005, DOI: 10.1590/S0103-90162005000300012
Abstract: clitoria fairchildiana (howard) is a tree largely distributed in brazil, used for urban arborization. in april 2001, the psyllid euphalerus clitoriae burckhardt & guajará was reported on this plant in the metropolitan areas of recife, pe, brazil. this report records the occurrence of e. clitoriae and studies some of its biological aspects in this area. with this purpose, c. fairchildiana leaves were sampled weekly, and e. clitoriae nymphs as well as aprostocetus sp. larvae and nymphs were collected and counted. the e. clitoriae population ranged from 2 to 90 nymphs per leaflet. the aprostocetus sp. percentage of parasitism ranged from 3 to 24%. the frequency curve for pygidium width ranged from 120 to 140; 200 to 240; 300 to 380; 460 to 580, and 720 to 820 mm for the first, second, third, fourth, and fifth instars, respectively. the incubation period for e. clitoriae eggs lasted 7.6 days. the nymphal stage lasted 5.7; 4.5; 4.8; 5.0, and 6.1 days for the first, second, third, fourth, and fifth instars, respectively. development time from egg to adult was 33.7 days. female longevity 8.6 days, with a daily fecundity of 118 eggs. the total viability of the immature stage was 74%, and the sex ratio was 0.5.
Occurence and biological aspects of the clitoria tree psyllid in Brazil  [cached]
Gondim Junior Manoel Guedes Corrêa,Barros Reginaldo,Silva Fernando Rodrigues da,Vasconcelos Geraldo José Nascimento de
Scientia Agricola , 2005,
Abstract: Clitoria fairchildiana (Howard) is a tree largely distributed in Brazil, used for urban arborization. In April 2001, the psyllid Euphalerus clitoriae Burckhardt & Guajará was reported on this plant in the metropolitan areas of Recife, PE, Brazil. This report records the occurrence of E. clitoriae and studies some of its biological aspects in this area. With this purpose, C. fairchildiana leaves were sampled weekly, and E. clitoriae nymphs as well as Aprostocetus sp. larvae and nymphs were collected and counted. The E. clitoriae population ranged from 2 to 90 nymphs per leaflet. The Aprostocetus sp. percentage of parasitism ranged from 3 to 24%. The frequency curve for pygidium width ranged from 120 to 140; 200 to 240; 300 to 380; 460 to 580, and 720 to 820 mm for the first, second, third, fourth, and fifth instars, respectively. The incubation period for E. clitoriae eggs lasted 7.6 days. The nymphal stage lasted 5.7; 4.5; 4.8; 5.0, and 6.1 days for the first, second, third, fourth, and fifth instars, respectively. Development time from egg to adult was 33.7 days. Female longevity 8.6 days, with a daily fecundity of 118 eggs. The total viability of the immature stage was 74%, and the sex ratio was 0.5.
Jumping Plant – Louse Cacopsylla (Hepatopsella) bidens ( ulc, 1907) (Hemiptera, Psyllidae) New Pest on Pear in Serbia
Du?anka Jerini?-Prodanovi?
Pesticidi i Fitomedicina , 2011,
Abstract: The problem of jumping plant – lice, an important pest on pear, appeared in the middle of the twentieth century and represents a direct consequence of pear cultivation on large areas with intensive application of agrotechnical, pomotechnical and chemical protectionmeasures. Three species of jumping plant – lice are known on pear in Serbia: Cacopsylla pyri, C. pyrisuga i C. pyricola, among which C. pyri is the most important pest in intensive orchards. During jumping plant – lice fauna research in Serbia, besides these three species, another one was determined as well - Cacopsylla bidens.In the period from 2005 to 2010, the presence and harmfulness of C. bidens were determined at 56 localities, both in intensive and extensive pear orchards. Besides on cultivated pears, C. bidens was also determined on wild species of Pyrus genus. In our conditions, C. bidens overwinters in adult stage on pear. The activation of theadults that have overwintered occurs at the beginning of March. The extended period of oviposition provides permanent presence of all developmental stages on plant, so the generations overlap. It can develop 3 to 4 generations per year. Since this is the first record of the species in Serbia, this paper describes basic morphological characteristics of the species, development cycle and distribution.
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