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Bioclimatic Thresholds, Thermal Constants and Survival of Mealybug, Phenacoccus solenopsis (Hemiptera: Pseudococcidae) in Response to Constant Temperatures on Hibiscus  [PDF]
Gudapati Sreedevi, Yenumula Gerard Prasad, Mathyam Prabhakar, Gubbala Ramachandra Rao, Sengottaiyan Vennila, Bandi Venkateswarlu
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0075636
Abstract: Temperature-driven development and survival rates of the mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) were examined at nine constant temperatures (15, 20, 25, 27, 30, 32, 35 and 40°C) on hibiscus (Hibiscus rosa-sinensis L.). Crawlers successfully completed development to adult stage between 15 and 35°C, although their survival was affected at low temperatures. Two linear and four nonlinear models were fitted to describe developmental rates of P. solenopsis as a function of temperature, and for estimating thermal constants and bioclimatic thresholds (lower, optimum and upper temperature thresholds for development: Tmin, Topt and Tmax, respectively). Estimated thresholds between the two linear models were statistically similar. Ikemoto and Takai’s linear model permitted testing the equivalence of lower developmental thresholds for life stages of P. solenopsis reared on two hosts, hibiscus and cotton. Thermal constants required for completion of cumulative development of female and male nymphs and for the whole generation were significantly lower on hibiscus (222.2, 237.0, 308.6 degree-days, respectively) compared to cotton. Three nonlinear models performed better in describing the developmental rate for immature instars and cumulative life stages of female and male and for generation based on goodness-of-fit criteria. The simplified β type distribution function estimated Topt values closer to the observed maximum rates. Thermodynamic SSI model indicated no significant differences in the intrinsic optimum temperature estimates for different geographical populations of P. solenopsis. The estimated bioclimatic thresholds and the observed survival rates of P. solenopsis indicate the species to be high-temperature adaptive, and explained the field abundance of P. solenopsis on its host plants.
Parasitic Effects of Solitary Endoparasitoid, Aenasius bambawalei Hayat (Hymenoptera: Encyrtidae) on Cotton Mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae)  [PDF]
Muhammad Qammar Shahzad, Zain Ul Abdin, Saqi Kosar Abbas, Muhammad Tahir, Fiaz Hussain
Advances in Entomology (AE) , 2016, DOI: 10.4236/ae.2016.42010
Abstract: Parasitization has an enormous impact on host physiology, development and reproduction. The effect of parasitism by endoparasitoid, Aenasius bambawalei Hayat (Hymenoptera: Encyrtidae) on survival and reproduction of mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) on different host stages was studied. Our data reveals that host mealybugs parasitized by the wasp at the 2nd instar stage were died during the 3rd instar stage of their life. However, those parasitized at the 3rd instar stage could reach the adult stage and were able to produce their progeny. After 6 days of parasitization, all parasitized hosts of the 2nd, 3rd and adult stages were died except the 1st instar. Results showed that parasitized host mealybugs had significantly lower reproductive potential than the unparasitized ones. Maximum parasitoid emergence was recorded in the 3rd instar host stage. This basic research regarding survival and reproduction of the parasitized host mealybugs would be very helpful in devising sustainable biological control strategies for cotton mealybug.
Does Mutualism Drive the Invasion of Two Alien Species? The Case of Solenopsis invicta and Phenacoccus solenopsis  [PDF]
Aiming Zhou, Yongyue Lu, Ling Zeng, Yijuan Xu, Guangwen Liang
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0041856
Abstract: Although mutualism between ants and honeydew-producing hemipterans has been extensively recognized in ecosystem biology, however few attempts to test the hypothesis that mutualism between two alien species leads to the facilitation of the invasion process. To address this problem, we focus on the conditional mutualism between S. invicta and P. solenopsis by field investigations and indoor experiments. In the laboratory, ant colony growth increased significantly when ants had access to P. solenopsis and animal-based food. Honeydew produced by P. solenopsis also improved the survival of ant workers. In the field, colony density of P. solenopsis was significantly greater on plots with ants than on plots without ants. The number of mealybug mummies on plants without fire ants was almost three times that of plants with fire ants, indicating a strong effect of fire ants on mealybug survival. In addition, the presence of S. invicta successfully contributed to the spread of P. solenopsis. The quantity of honeydew consumption by S. invicta was significantly greater than that of a presumptive native ant, Tapinoma melanocephalum. When compared with the case without ant tending, mealybugs tended by ants matured earlier and their lifespan and reproduction increased. T. melanocephalum workers arrived at honeydew more quickly than S. invicta workers, while the number of foraging S. invicta workers on plants steadily increased, eventually exceeding that number of T. melanocephalum foragers. Overall, these results suggest that the conditional mutualism between S. invicta and P. solenopsis facilitates population growth and fitness of both species. S. invicta tends to acquire much more honeydew and drive away native ants, promoting their predominance. These results suggest that the higher foraging tempo of S. invicta may provide more effective protection of P. solenopsis than native ants. Thus mutualism between these two alien species may facilitate the invasion success of both species.
First Record of Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) on Hibiscus rosa-sinensis in Nigeria
A.J. Akintola,A.T. Ande
Agricultural Journal , 2013,
Abstract: A survey of mealybugs found in the southern guinea savanna of Nigeria was conducted and P. solenopsis was found on Hibiscus rosa-sinensis plant where the adult aggregated on the stem of the plant. Specimen of this was sent to Systematic Entomology Laboratory in the U.S and was identified by Douglas Miller (the editor of scale insect forum). The adult recovered were females and the mouth part is the opisthorhynchous type with a long straight aseptate stylet. The organism was host specific and stationary. The tip of the abdomen was protruded with long setae. Various body appendages were measured and the life cycle studies conducted. Comparison between this mealybug and other related species was done and documented for the first time in Nigeria.
The Cassava Mealybug (Phenacoccus manihoti) in Asia: First Records, Potential Distribution, and an Identification Key  [PDF]
Soroush Parsa, Takumasa Kondo, Amporn Winotai
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0047675
Abstract: Phenacoccus manihoti Matile-Ferrero (Hemiptera: Pseudococcidae), one of the most serious pests of cassava worldwide, has recently reached Asia, raising significant concern over its potential spread throughout the region. To support management decisions, this article reports recent distribution records, and estimates the climatic suitability for its regional spread using a CLIMEX distribution model. The article also presents a taxonomic key that separates P. manihoti from all other mealybug species associated with the genus Manihot. Model predictions suggest P. manihoti imposes an important, yet differential, threat to cassava production in Asia. Predicted risk is most acute in the southern end of Karnataka in India, the eastern end of the Ninh Thuan province in Vietnam, and in most of West Timor in Indonesia. The model also suggests P. manihoti is likely to be limited by cold stress across Vietnam's northern regions and in the entire Guangxi province in China, and by high rainfall across the wet tropics in Indonesia and the Philippines. Predictions should be particularly important to guide management decisions for high risk areas where P. manihoti is absent (e.g., India), or where it has established but populations remain small and localized (e.g., South Vietnam). Results from this article should help decision-makers assess site-specific risk of invasion, and develop proportional prevention and surveillance programs for early detection and rapid response.
Nuevas citas y huéspedes de Phenacoccus para la Argentina (Hemiptera: Pseudococcidae) New records and host plants of Phenacoccus from Argentina (Hemiptera: Pseudococcidae)  [cached]
María C. Granara de Willink
Revista de la Sociedad Entomol?3gica Argentina , 2003,
Abstract: Se cita por primera vez para la Argentina a: Phenacoccus madeirensis Green, Phenacoccus manihoti Matile-Ferrero y Phenacoccus solenopsis Tinsley y se dan a conocer nuevos huéspedes de Phenacoccus crassus Granara de Willink, Phenacoccus parvus Morrison y Phenacoccus similis Granara de Willink. Phenacoccus madeirensis Green, Phenacoccus manihoti Matile-Ferrero and Phenacoccus solenopsis Tinsley, first records from Argentina and new hosts plants of Phenacoccus crassus Granara de Willink, Phenacoccus parvus Morrison y Phenacoccus similis Granara de Willink.
Nuevas citas y huéspedes de Phenacoccus para la Argentina (Hemiptera: Pseudococcidae)
Granara de Willink,María C.;
Revista de la Sociedad Entomol?3gica Argentina , 2003,
Abstract: phenacoccus madeirensis green, phenacoccus manihoti matile-ferrero and phenacoccus solenopsis tinsley, first records from argentina and new hosts plants of phenacoccus crassus granara de willink, phenacoccus parvus morrison y phenacoccus similis granara de willink.
Virulence measurement of Beauveria bassiana strain to Phenacoccus solenopsis Tinsley

- , 2015,
Abstract: 采用点滴法测定了球孢白僵菌MZ041016菌株在2.0×105、 2.0×106、 2.0×107和2.0×108 个/mL 4个浓度的分生孢子液对扶桑绵粉蚧(Phenacoccus solenopsis Tinsley)若虫和成虫的致病力。结果表明:球孢白僵菌MZ041016菌株对扶桑绵粉蚧具有很强的致病性,在分生孢子液2.0×108个/mL浓度时对若虫和成虫的致病力最强。扶桑绵粉蚧1龄、2龄、3龄若虫和雌成虫的致死中浓度分别为(2.10±0.06)×106、 (2.43±0.06)×106、 (3.20±0.06)×106、 (3.54±0.06)×106 个/mL,致死中时间分别为(4.52±0.17)、 (5.34±0.51)、(6.12±0.35)、 (6.48±0.32) d。
The toxicity bioassay of Beauveria bassiana Vuillemin MZ041016 to Phenacoccus solenopsis Tinsley during four different concentrations on 2.0×105, 2.0×106,2.0×107,2.0×108 spores per mL was measured by topical application in laboratory, and 1st,2nd, 3rd of larvae and female adults of P.solenopsis were vaccinated respectively.The results indicated that the virulence of B.bassiana MZ041016 to P.solenopsis was high.The accumulative mortality was highest in concentration of 2.0×108 spores per mL. The median lethal concentration of 1st,2nd, 3rd of larvae and adults of the P.solenopsis was (2.10±0.06)×106,(2.43±0.06)×106,(3.20±0.06)×106,(3.54±0.06)×106 spores per mL respectively; the median lethal time was (4.52±0.17),(5.34±0.51),(6.12±0.35),(6.48±0.32) d respectively.
Etude de l'entomofaune associée à la cochenille du manioc Phenacoccus manihoti Matile-Ferrero, en C te d'Ivoire
Obame Minko, D.,Békon, AK.
Tropicultura , 2005,
Abstract: Study of Insectfauna Associated to the Cassava Mealybug Phenacoccus manihoti Matile-Ferrero in Ivory Coast. Within the biocoenosis of cassava mealybug, Phenacoccus manihoti, in Ivory Coast, the presence of many predator and parasite insects is reported. The main predators of the mealybugs are Coccinellidae and particularly Scymnus couturieri. Among parasites, the most numerous are Encyrtidae hymenoptera. Some, like Epidinocarsis lopezi, attack directly mealybugs and are thus useful assistants. Others live as parasite on predators or parasites of mealybugs and so reduce the efficiency of those assistants. In addition, some other insects are present, whose role is not known. The authors note the relative abundance of all the collected species.
Jasmonic acid elicits oxidative defense and detoxification systems in Cucumis melo L. cells
Nafie, Eetezaz;Hathout, Tahany;Al Mokadem, Al Shyma;
Brazilian Journal of Plant Physiology , 2011, DOI: 10.1590/S1677-04202011000200008
Abstract: this study investigated whether a jasmonic acid (ja) elicitation strategy developed in a conventional cell suspension culture could evoke melon resistance mechanisms, including secondary metabolite production. twenty one day cultured melon cell suspensions grown in ms1 medium were supplemented with ja at the concentrations of 0.5, 5.0 and 10 μmol. melon cultures were sampled 24, 48 and 72 h post elicitation to evaluate different defense related factors such as antioxidant enzymes, ascorbate metabolism and phenolic compounds. results suggest that melon cells respond to ja reprogramming the primary and secondary metabolism which will result in melon plantlets with enhanced resistance against diverse stress conditions through the production of specific bioactive molecules. jasmonic acid elicited melon cells exhibited enhanced oxidative enzymes activities and ascorbic acid, coumarin and p-coumaric amounts were found without growth retardation. induced intracellular ja functions as a signal transducer acting upstream to h2o2, which is a secondary messenger triggering jasmonic signaling cascades by activating certain late genes that regulate the activity of catalase, peroxidase and de novo synthesis of five isozymes, ascorbic peroxidase detoxifying enzymes concomitant with ascorbate compound. secondary metabolite production in melon cells seems to be activated upon ja exposure suggesting that this cell culture could be used as a source for rapid and increased production of coumarin, p-coumaric, ascorbic acid and likely other specific phenylpropanoids. these data provide further evidences for a role of jasmonic acid in the intracellular signal cascade that results in the accumulation of secondary compounds and ultimately induced melon resistance. this approach could assist further in understanding the metabolic mechanisms operating in melon cells under stress, and thus how to control them.
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