Protopulvinaria Pyriformis Research Articles

Pyriform scale, Protopulvinaria pyriformis (Cockerell, 1894) (Hemiptera: Coccidae), infesting citrus trees in Morocco

AbstractIn the coastal area of North‐Western Morocco, 43 sites in four provinces were surveyed between spring 2022 and autumn 2023 for the presence of pest scale insects (Hemiptera: Coccomorpha) on citrus trees. A known citrus pest species, pyriform scale, Protopulvinaria pyriformis (Cockerell, 1894) (Coccidae), was found at four sites. This is the first paper reporting pyriform scale on citrus in Morocco so a species description based on 62 slide‐mounted adult females is provided. Currently, P. pyriformis is not causing damage on citrus in Morocco, but potentially it might become a pest on this crop or other commercial fruit crops, such as avocado. Populations of P. pyriformis therefore should be monitored to detect any spread of the scale to other areas and crops. The infestations were found to be associated with a predator Chilocorus bipustulatus (Linnaeus) (Coleoptera: Coccinellidae) and two parasitic wasps: an ectoparasitoid, Aphytis sp. (Hymenoptera: Aphelinidae), and an unidentified endoparasitoid (Hymenoptera: Chalcidoidea).

Efficacy of Aloe vera extract on the growth of Schefflera arboricola plants and its resistance to pyriform scale Protopulvinaria pyriformis (Cockerell).

Efficacy of Aloe vera extract on the growth of Schefflera arboricola plants and its resistance to pyriform scale Protopulvinaria pyriformis (Cockerell).

First record of the pyriform scale, Protopulvinaria pyriformis Cockerell (Hemiptera: Coccidae), on Laurus nobilis L. in Tunisia

AbstractThis paper reports the first finding of the pyriform scale, Protopulvinaria pyriformis Cockerell (1894), infesting laurel, Laurus nobilis L., in Tunisia. The pest was found in May 2020 in a private garden in the region of Jawhara, Governorate of Sousse, Coastal Tunisia. Heavily infested laurel trees were observed on which the upper surfaces of leaves were extensively covered with a black sooty mould. Brief notes on diagnostic features of this scale and symptoms of infestation are presented. Possible pest risks and control measures aimed at avoiding the potential further spread of the pest in Tunisia are discussed.

New records of scale insects and mealybugs (Hemiptera: Coccomorpha) in Kenya

AbstractSeventeen scale insect and mealybug species (Hemiptera: Sternorrhyncha: Coccomorpha) are recorded from Kenya for the first time. Specimens were collected during surveys in 2017‒2020 and the new records comprised Coccidae: the species group of Ceroplastes rusci (L.) and Protopulvinaria pyriformis (Cockerell); Diaspididae: Africonidia mkuzensis Ben‐Dov, Aonidiella rex Balachowsky, Aspidiella sacchari (Cockerell), Aulacaspis yasumatsui Takagi, Cryptoparlatoreopsis ?meccae Hall, Fiorinia fioriniae (Targioni Tozzetti), Lepidosaphes tokionis (Kuwana), Oceanaspidiotus spinosus (Comstock), Parlatoria proteus (Curtis), Pinnaspis aspidistrae (Signoret) and Pseudaulacaspis pentagona (Targioni Tozzetti); and Pseudococcidae: Chaetococcus bambusae (Maskell), Phenacoccus parvus Morrison, Phenacoccus madeirensis Green and Phenacoccus solenopsis Tinsley. Information is also provided on the Diaspididae: Parlatoria pergandii Comstock and Parlatoria ziziphi (Lucas) following the first report of these 2 species published earlier this year. Some of the above species were damaging crops.

The Impact of Climate Change on Seasonal Abundance of The Pyriform Scale, Protopulvinaria Pyriformis (Cockerell) (Hemiptera: Coccidae) and Its Predatorsin Alexandria, Egypt

The pyriform scale, Protopulvinaria pyriformis Cockerell (Hemiptera: Coccidae) is considered as one of the mostimportant pest infesting fruit trees and ornamental plants. Study of the seasonal fluctuation of nymphs, adult females andtotal population was carried out on guava trees,Psidium guajava ( family Myrtaceae) and the ornamental plant,umbrellatree, Schefflera arboricola (Hayata) (Family: Araliaceae)in Alexandria Governorate, Egyptduring two successive yearsfrom January 2015 till December 2016. P. pyriformis nymphs, adult females and total population achieved two peaks onguava and schefflera in the two years of study. During the course of this study, two predators were associated with P.pryiformis these predators were Scymnus syriacus L. (Coleoptera: Coccinellidae) and Chrysoperla carnea (Steph.)(Neuroptera: Chrysopidae). S. syriacus showed four peaks in the first year of study 2015 and three peaks in the secondyear 2016, while C. carnea showed three peaks in the two years of study on guava. Multi regression analysis indicatedthat the predators play good effect on the population of P. pryiformis on guava since E.V% was 39.9 % in 2015 and 40.21% in 2016 while they were less on schefflera (28.76 % & 36.24 % in the two years of study respectively).The compoundeffect of weather factors (E.V.%) recorded 54.21% & 61.69 % of the total population on guava and 64.48% & 55.51% onschefflera in the two year of study, in respect.

The use of bio-based liquid formulations in pest control of citrus groves

Over the last decade, many pest control techniques have seen substantial changes mainly due to the EU directive 2009/128/EC which relates to the registration process for new products and their toxicity. Thus, the list of pesticides is continuously revised and modified to include new plant protection products which have to be safer for human health, food quality and less polluting for the environment. These decisions increase the importance of and consequently the interest in non-chemical alternatives, including physical systems and bio-based products and the Directive clearly reports the need to define new non-chemical control systems in crop management and defense, as a partial or total alternative to conventional pesticides.At the same time, several crops particularly adapted to the pedoclimatic conditions of southern Italy, such as trees belonging to the genus Citrus, are suffering due to presence of several pests and pathogens that can lead to considerable reductions of yield quality and quantity, and that are often resistant to the most common pesticides. This paper reports and discusses the results of trials carried out in 2011 on the efficacy of natural formulations based on products deriving from Brassica carinata (Ethiopian mustard) on Citrus groves in southern Italy against aphids (Aphis gossypi), mites (Tetranychus urticae, Panonychus citri), scales (Protopulvinaria pyriformis, Icerya purchasi, Unaspis yanonensis) and whiteflies (Aleurothrixus floccosus,). In general, the results were positive, suggesting that the experimental liquid formulations can represent a total or partial alternative to agrochemical pesticides and also an interesting option for organic farming.

Formation of Stylet Sheaths in āere (in air) from Eight Species of Phytophagous Hemipterans from Six Families (Suborders: Auchenorrhyncha and Sternorrhyncha)

Stylet sheath formation is a common feature among phytophagous hemipterans. These sheaths are considered essential to promote a successful feeding event. Stylet sheath compositions are largely unknown and their mode of solidification remains to be elucidated. This report demonstrates the formation and solidification of in āere (in air) produced stylet sheaths by six hemipteran families: Diaphorina citri (Psyllidae, Asian citrus psyllid), Aphis nerii (Aphididae, oleander/milkweed aphid), Toxoptera citricida (Aphididae, brown citrus aphid), Aphis gossypii (Aphididae, cotton melon aphid), Bemisia tabaci biotype B (Aleyrodidae, whitefly), Homalodisca vitripennis (Cicadellidae, glassy-winged sharpshooter), Ferrisia virgata (Pseudococcidae, striped mealybug), and Protopulvinaria pyriformis (Coccidae, pyriform scale). Examination of in āere produced stylet sheaths by confocal and scanning electron microscopy shows a common morphology of an initial flange laid down on the surface of the membrane followed by continuous hollow core structures with sequentially stacked hardened bulbous droplets. Single and multi-branched sheaths were common, whereas mealybug and scale insects typically produced multi-branched sheaths. Micrographs of the in āere formed flanges indicate flange sealing upon stylet bundle extraction in D. citri and the aphids, while the B. tabaci whitefly and H. vitripennis glassy-winged sharpshooter flanges remain unsealed. Structural similarity of in āere sheaths are apparent in stylet sheaths formed in planta, in artificial diets, or in water. The use of ‘Solvy’, a dissolvable membrane, for intact stylet sheath isolation is reported. These observations illustrate for the first time this mode of stylet sheath synthesis adding to the understanding of stylet sheath formation in phytophagous hemipterans and providing tools for future use in structural and compositional analysis.

Novel defenses of Protopulvinaria pyriformis (Hemiptera: Coccidea) against its major parasitoid Metaphycus helvolus (Hymenoptera: Encyrtidae): Implications for biological control of soft scales

Protopulvinaria pyriformis (Cockerell) (Hemiptera: Coccidae), a scale native to South America, is a major pest of laurel, Laurus nobilis L., and a potential pest of other ornamental plants in urban green areas. We evaluated the potential of Metaphycus helvolus (Compere) (Hymenoptera: Encyrtidae), its major parasitoid, as a biological control agent against P. pyriformis. This parasitoid was imported from South Africa to control soft scales in Europe more than 20years ago. Three factors limited its efficacy: (i) the scale frequently thwart parasitoid attack by removing its stylet and wiggling, a unique defense in soft scales, (ii) scale honeydew extended M. helvolus lifespan little more than water, and (iii) P. pyriformis did not encapsulate Metaphycus spp. eggs but immature parasitoids died during their prepupal stage, which may have been caused by laurel plant secondary compounds from laurel. This parasitoid mortality had not been previously reported in immature parasitoids of genus Metaphycus. These three novel aspects should be considered when choosing a suitable parasitoid in future soft scale biological control programs.

Parasitoid community of Protopulvinaria pyriformis (Hemiptera: Coccidae) on laurel: Influence of host size, seasonal trend and aggregation on its main parasitoid

The phenology of Protopulvinaria pyriformis (Cockerell) (Hemiptera: Coccidae) and its parasitoid complex were studied on laurel Laurus nobilis L. in urban green spaces of Eastern Spain from March 2008 to January 2010. P. pyriformis is bivoltine, gravid females peaked on spring and fall and the 2nd and 3rd instars were present throughout the year. The natural parasitoid community of P. pyriformis consisted of three primary parasitoids and four facultative hyperparasitoid species. Metaphycus helvolus (Compere) (Hymenoptera: Encyrtidae) accounted for 98% of the parasitoids recovered. Although M. helvolus parasitized all the scale instars, it attacked P. pyriformis mostly at the end of the spring, when scales were larger. M. helvolus behaved as a solitary parasitoid and its secondary sex ratio was male biased when it parasitized the 2nd instar. Its secondary sex ratio became female biased when it parasitized scales larger than 1.1 mm. M. helvolus behaved as a facultative gregarious parasitoid and its secondary sex ratio was always female biased (0.3 males per scale) when it parasitized the 3rd instar and the adults. The number of eggs allocated per host, as well as the number of parasitoids that emerged, increased with scale size. Mostly, broods of two to four parasitoids emerged from these scales. M. helvolus showed inverse host density dependence, parasitism decreased as the number of scales per leaf increased. The implications of these results on the biological control of this and other soft scales are discussed.

Phenological and ecological aspects of Protopulvinaria pyriformis (Cockerell) (Hemiptera: Coccidae) in Greece

The ecology of the coccid Protopulvinaria pyriformis infesting the laurel Laurus nobilis was studied from October 2003 to September 2005 in SW Greece. The coccid is parthenogenetic and oviparous, producing increased amounts of honeydew throughout the year. It settles mainly on the lower leaf surface. The scale over- winters as egg, 1st and 2nd instar nymph and adult and completes several overlapping generations every year. The life cycle was estimated to last in nature *52 days during winter and 29-33 days during summer. Infestation density ranged between 0.3 and 2.8 live scales per cm 2 of leaf surface. Metaphycus helvolus was the only wasp found to parasitize P. pyriformis. Parasitism rate reached 31.2% during the second year of the study. The scale was able to resist parasitization by encapsulating the parasitoid's eggs. Maximum encapsulation rate was estimated up to 23% of the adult scales. Encapsulated eggs ranged from 1 to 5 eggs per adult scale. Predation rate reached 7% and it was attributed to the coccinellid Chilocorus bipustulatus. The above information could be important for planning a sus- tainable control strategy for this new pest in Greece.

831 Post-operative radiotherapy for soft tissue sarcoma of the anterior compartment of the thigh: should the sartorius muscle be included?

Since 1980 the pyriform scale, Protopulvinaria pyriformis (Cockerell) (Homoptera: Coccidae), has been an important pest of avocado in Israel.Field evaluation showed differences in the susceptibility of avocado cultivars to P. pyriforms; Nabal were the most infested, followed by Hass and Fuerte, whereas Ettinger was sometimes attacked when located close to infested Nabal or Hass trees.In a laboratory experiment P. pyriformis was able to develop and to reproduce on Nabal, Ein Vered and, to a lesser extent, on Hass. Survival of P. pyriformis populations was very low on Fuerte, Horshim and Wurz cultivars, whereas P. pyriformis settled more successfully on Ettinger, Pinkerton and Reed. Results from the laboratory experiment confirmed the actual infestation rates in avocado orchards.

832 Ifosfamide, carboplatin, etoposide induces a 50% overall response rate and 1 year overall survival rate in patients with recurrent/refractory soft tissue and bone sarcoma: Embryonal rhabdomyosarcoma histology and complete response to ICE are independent factors significantly associated with improved survival

Since 1980 the pyriform scale, Protopulvinaria pyriformis (Cockerell) (Homoptera: Coccidae), has been an important pest of avocado in Israel.Field evaluation showed differences in the susceptibility of avocado cultivars to P. pyriforms; Nabal were the most infested, followed by Hass and Fuerte, whereas Ettinger was sometimes attacked when located close to infested Nabal or Hass trees.In a laboratory experiment P. pyriformis was able to develop and to reproduce on Nabal, Ein Vered and, to a lesser extent, on Hass. Survival of P. pyriformis populations was very low on Fuerte, Horshim and Wurz cultivars, whereas P. pyriformis settled more successfully on Ettinger, Pinkerton and Reed. Results from the laboratory experiment confirmed the actual infestation rates in avocado orchards.

Further studies of the encapsulation of eggs ofMetaphycus spp. (Hym.: Encyrtidae) by the pyriform scale,Protopulvinaria pyriformis (Hom.: Coccidae)

The encapsulation of eggs ofMetaphycus swirskii Annecke & Mynhardt (Hymenoptera: Encyrtidae) by the pyriform scale,Protopulvinaria pyriformis (Cockerell) (Homoptera: Coccidae), collected in the coastal plain of Israel, was determined during April 1986 to May 1987. The rates of encapsulation were low in November (13.0%) and relatively high in April, May, August and September (32.0–89.0%).

Seasonal variations in the encapsulation of eggs of the encyrtid parasitoid Metaphycus stanleyi by the pyriform scale, Protopulvinaria pyriformis

AbstractEncapsulation of eggs of the introduced parasitoid Metaphycus stanleyi Compere (Hymenoptera: Encyrtidae) by the pyriform scale, Protopulvinaria pyriformis (Cockerel!) (Homoptera: Coccidae) under both greenhouse and field conditions, at Bet Dagan, was found to occur almost all year round (1986–1988). However, encapsulation rates varied considerably during the different seasons and were correlated with the ambient temperatures. The rates of efficient encapsulation (i) in scales infesting Hedera helix and Schefflera arboricola under greenhouse conditions, were lowest during December to May (6–17%) and highest during July to September (78–100%); (ii) in scales infesting avocado in the orchard, were lowest during October to May (0–11%) and highest during June to August (54–57%). Under greenhouse conditions, encapsulation rates did not differ in scales grown on H. helix and on S. arboricola, but were significantly lower in scales grown on avocado. Encapsulation by scales infesting S. arboricola was more frequent at temperatures ranging from 20–28 °C, than from 7–23 °C.The increased resistance by encapsulation of P. pyriformis to successful parasitization by M. stanleyi during the summer, may account for the inability of the parasitoid to prevent the autumn and winter outbreaks of the pest.

Susceptibility of avocado cultivars to the pyriform scale, Protopulvinaria pyriformis (Cockerell) (Homoptera: Coccidae)

Since 1980 the pyriform scale, Protopulvinaria pyriformis (Cockerell) (Homoptera: Coccidae), has been an important pest of avocado in Israel. Field evaluation showed differences in the susceptibility of avocado cultivars to P. pyriforms; Nabal were the most infested, followed by Hass and Fuerte, whereas Ettinger was sometimes attacked when located close to infested Nabal or Hass trees. In a laboratory experiment P. pyriformis was able to develop and to reproduce on Nabal, Ein Vered and, to a lesser extent, on Hass. Survival of P. pyriformis populations was very low on Fuerte, Horshim and Wurz cultivars, whereas P. pyriformis settled more successfully on Ettinger, Pinkerton and Reed. Results from the laboratory experiment confirmed the actual infestation rates in avocado orchards.

Response of three soft scales (Homoptera: Coccidae) to parasitization byMetaphycus Smrskii

The response of three soft scales: the pyriform scale —Protopulvinaria pyriformis (Cockerell), the mango shield scale —Protopulvinaria mangiferae (Green), and the capparis soft scale —Coccus capparidis (Green), to paiasitization by the parasiteMetaphycus swirskii Annecke & Mynhardt (Hymenoptera:Encyrtidae), was studied. Although the parasite was able to complete its development in any of these three host species, different rates of mortality of parasite immatures were recorded in the various hosts. Parasite mortality inP. pyriformis was due to egg encapsulation only and was higher in the field than under laboratory conditions (53.1%vs. 27.7%, respectively). InP. mangiferae a total of 55.4% mortality was observed, while inC. capparidis it reached only 14.0%, rendering the latter the most suitable of the three soft scales tested, for successful development ofM. swirskii.

Descriptions of the Immature Stages of Protopulvinaria pyriformis (Cockerell) (Homoptera: Coccidae)

The 3 immature instars of the female pyriform scale insect, Protopulvinaria pyriformis (Cockerell), are described and illustrated. A key for the separation of all developmental stages is provided.