scholarly journals Are synthetic pheromone captures predictive of parasitoid densities as a kairomonal attracted tool?

2011 ◽  
Vol 43 (1) ◽  
pp. 23 ◽  
Author(s):  
Mohamed Hassan Bayoumy ◽  
Mehmet Bora Kydan ◽  
Ferenc Kozár

Abundance of White Peach scale (WPS), <em>Pseudaulacaspis pentagona </em>(Targioni-Tozzetti) and San Jos&eacute; scale (SJS), <em>Diaspidiotus perniciosus </em>(Comstock) (Hemiptera: Diaspididae) adult males and their attracted parasitoids were monitored using pheromone and sticky tape traps in an orchard of Budapest, Hungary, during 2010. In this study, we tried answer on the question raised whether synthetic commercial pheromones of WSP or SJS could work as a kairomonal stimulant and positively attract higher numbers of the specialized parasitoids. Although pheromone traps attracted a wide range of parasitoid species, most of them were accidentally. However, the parasitoid <em>Thomsonisca amathus</em> (Walker) (Hymenoptera: E ncyrtidae) and the parasitoid <em>Encarsia perniciosi </em>(Tower) (Hymenoptera: Aphelinidae) significantly respond to the sex pheromones of WPS and SJS, respectively, suggesting that they may play an important role in host location.

2017 ◽  
Vol 20 (1) ◽  
pp. 17
Author(s):  
M. H. Bayoumy ◽  
K. Fetyko ◽  
I. Tobias ◽  
Z. Konczné Benedicty ◽  
É. Szita ◽  
...  

A study has been conducted to monitor geographical spread of the white peach scale Pseudaulacaspis pentagona (Targioni Tozzetti) (Hemiptera: Diaspididae) (WPS) and its parasitoid populations in 32 stops of the Hungarian highways (M0. M1, M3, M5 and M7) using pheromone traps during 2009 and 2010. In addition to the data collected in the current study, previous data were used to investigate the population trend of this pest from 2007 to 2010. The number of males recorded in traps placed on highways was much lower than in the sites close to urban areas (M0). Our data support results of previous studies which suggest the spreading of white peach scale by vehicles (“transport vector”). The significant decrease in the WPS male catches from 2007 to 2010 might indicate the lowering of the population levels of this pest in the area of the study. Eight hymenopterous parasitoid species were captured in pheromone traps. Coccophagus sp. was the predominate species in pheromone traps of WPS in M7, how-ever they may be associated with another coccid species. The identity of scale males and some parasitoids was proved by molecular markers.


2021 ◽  
Author(s):  
Xianzhe Zheng ◽  
Qiaohong Li ◽  
Qian Zhang ◽  
Guanle Wu ◽  
Ke Tao ◽  
...  

Abstract Background:Kiwifruit is a common and popular fruit around the world. However, white peach scale (Pseudaulacaspis pentagona) [Targioni-Tozzetti], a scale insect with a wide range of hosts, seriously affects the yield and quality of kiwifruit. To investigate the differences in resistance of different kiwifruit cultivars to Pseudaulacaspis pentagona, cellular structure and gene expression assays were used to explain the mechanism. Results:In this study, based on the stability of the rate of injury fruit, we selected four cultivars from fifty kiwifruits for in-depth study, including “LC-04285”, “CF-3”, “DA-7B” and “Hayward”. By analyzing the differences in the anatomical structure of the canes of these cultivars, we found that the resistant cultivar "LC-04285" had thicker cuticle, denser epidermis and cortex. The real-time quantitative PCR data indicated that the expression levels of genes related to cuticle synthesis and formation of epidermis and cortex are also higher in “LC-04285”. Jasmonic acid (JA) is an important hormone involved in plant defense against many insect pests. In this study, we found that the expression levels of JA receptor COI1 were higher in “LC-04285”. However, the expression levels of AcJAZs, which played negative role in JA signaling, were higher in susceptible cultivar “Hayward”. Besides, the expression levels of AcICS, AcPAL4, AcPAL5, and AcNPRs, which were involved in salicylic acid (SA) synthesis and SA response, were also higher in “LC-04285”. Conclusions:Our results revealed the mechanism of kiwifruit resistance to P. pentagona at the molecular and cellular levels. This study provided useful guidance for breeding insect-resistant kiwifruit in future.


2019 ◽  
Vol 12 (1) ◽  
pp. 12-21 ◽  
Author(s):  
A.H. Toorani ◽  
H. Abbasipour ◽  
L. Dehghan-Dehnavi

Summary The white peach scale, Pseudaulacaspis pentagona Targioni-Tozzetti (Hemiptera: Diaspididae), is one of the most important and destructive polyphagous pests of the Rosaceae family trees. Population fluctuations and biodiversity of the hymenopteran parasitoid species associated with the pest were studied in six kiwi orchards in Iran, during one-year period. Parasitoid species abundance, species diversity indices and evenness indices were calculated. Most of the parasitoid species were dominant or eudominant. Based on the alpha diversity indices, the Najarkola region had high diversity and the Kharatkola region had low diversity. The Paeendasteh region (based on Simpson’s Diversity on Camargo evenness indices) and the Samnakola region (based on the modified Nee, and on Smith and Wilson evenness indices) were less uniform. Among the recorded parasitoids, Encarsia berlesei Howard (Hymenoptera: Aphelinidae), followed by Aphytis proclia Walker (Hymenoptera: Aphelinidae), had the highest population in all orchards.


2017 ◽  
Vol 8 ◽  
pp. 5 ◽  
Author(s):  
D.S. Kyparissoudas

During 1986-1988 the relationship between catches of San Jose scale (SJS), Quadraspidiotus perniciosus (Comstock), adult males in pheromone traps and crawlers on sticky-tape traps was studied as a basis of SJS crawler control in apple orchards of Northern Greece. Spring male flight began in mid-to late April and crawler emergence occurred in mid-to late May. Crawlers were active for a period of 6-7 weeks until early July. Peak crawler emergence occurred approximately 12 days after the first emergence, or 42 days after the first males were captured on pheromone traps. Because in our 3-year study the crawler emergence occurred 29-31 days or 191-202 day-degrees (base 10.5°C) after the capture of the first male, we conclude that a consistent time-relationship exists between the two events. Two insecticide treatments, one three days after the first crawler appearance and another 10 days later (near peak crawler activity), provided the best control against the first generation of scale.


1990 ◽  
Vol 25 (2) ◽  
pp. 303-310 ◽  
Author(s):  
Christine A. Nalepa ◽  
John R. Meyer

Hymenopteran parasites (adults) and mobile stages (crawlers, adult males) of white peach scale, Pseudaulacaspis pentagona (Targioni-Tozzetti), were monitored biweekly (1986) or weekly (1987) in a peach orchard from April to December. The scale exhibited three peaks of crawler emergence, and a partial fourth generation was observed in both years. Three species of hymenopteran parasites consistently collected from traps were the primary parasites Encarsia berlesi (Howard) and Aphytis proclia (Walker), and the hyperparasite Marietta carnesi (Howard). Populations of all three parasites showed seasonal peaks of activity that differed in the two years of this study. Winter samples taken in 1985, and from 1987 through 1989 indicated differences between years in the ratio of parasites to hyperparasites overwintering.


1995 ◽  
Vol 85 (4) ◽  
pp. 531-539 ◽  
Author(s):  
P.A. Pedata ◽  
M.S. Hunter ◽  
H.C.J. Godfray ◽  
G. Viggiani

AbstractWhite peach scale, Pseudaulacaspis pentagona (Targioni-Tozzetti) (Homiptera: Diaspididae), was a serious pest of mulberry until it was the subject of a successful biological control programme in Italy at the turn of the century. Since the 1950s it has returned as a sporadic pest of commercial peach and, more recently, kiwi fruit orchards. We sampled white peach scale in an unmanaged mulberry orchard in coastal Campania over a 17 month period to measure the impact, relative abundance, and interactions of the parasitoids in the absence of pesticides. Sampled scales were dissected, and the immature stages of the parasitoids identified. Mean densities of white peach scale varied with month from 3–15/9 cm2 on primary (interior) branches and 15–100/1.5–2 m secondary (exterior) branch. The generalist ectoparasitoid Aphytis proclia (Walker) was most abundant, followed by two specialist endoparasitoids, Encarsia berlesei (Howard) and Pteroptrix orientalis (Silvestri) (all Hymenoptera: Aphelinidae). Primary parasitism also varied with month from 25–85% on primary branches and 20–90% on secondary branches. Parasitism on primary branches was inversely density-dependent, but was densityindependent on secondary branches. Low levels of superparasitism were generally observed in E. berlesei and P. orientalis (0–6%), but were higher in A. proclia (0–21%). Multiple parasitism of hosts by E. berlesei and A. proclia was fairly common (up to 24% of E. berlesei immatures were found sharing a host with A. proclia), and A. proclia was the probable winner of within-host competitions. The hyperparasitoid Azotus perspeciosus (Girault) (Hymenoptera: Aphelinidae) parasitized late pre-imaginal instars of all three primary parasitoid species. There was no significant difference in hyperparasitism of the three primary parasitoid species, but the rate of hyperparasitism was inversely related to the total density of primary parasitoids.


2012 ◽  
Vol 58 (12) ◽  
pp. 1703-1710 ◽  
Author(s):  
Yeo-Min Yun ◽  
Julianne Cook Botelho ◽  
Donald W Chandler ◽  
Alex Katayev ◽  
William L Roberts ◽  
...  

BACKGROUND Testosterone measurements that are accurate, reliable, and comparable across methodologies are crucial to improving public health. Current US Food and Drug Administration–cleared testosterone assays have important limitations. We sought to develop assay performance requirements on the basis of biological variation that allow physiologic changes to be distinguished from assay analytical errors. METHODS From literature review, the technical advisory subcommittee of the Partnership for the Accurate Testing of Hormones compiled a database of articles regarding analytical and biological variability of testosterone. These data, mostly from direct immunoassay-based methodologies, were used to specify analytical performance goals derived from within- and between-person variability of testosterone. RESULTS The allowable limits of desirable imprecision and bias on the basis of currently available biological variation data were 5.3% and 6.4%, respectively. The total error goal was 16.7%. From recent College of American Pathologists proficiency survey data, most currently available testosterone assays missed these analytical performance goals by wide margins. Data from the recently established CDC Hormone Standardization program showed that although the overall mean bias of selected certified assays was within 6.4%, individual sample measurements could show large variability in terms of precision, bias, and total error. CONCLUSIONS Because accurate measurement of testosterone across a wide range of concentrations [approximately 2–2000 ng/dL (0.069–69.4 nmol/L)] is important, we recommend using available data on biological variation to calculate performance criteria across the full range of expected values. Additional studies should be conducted to obtain biological variation data on testosterone from women and children, and revisions should be made to the analytical goals for these patient populations.


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