Literatura académica sobre el tema "Insect pests Ladybugs. Mealybugs"

Removal of pests on export fruit before packing using high pressure waterwashing is used commercially in New Zealand for apples and avocados and has the potential to be extended to other fruits and vegetables Mealybugs thrips and mites are intercepted on exported capsicums and the presence of species of quarantine importance results in methyl bromide fumigation which disrupts export reduces fruit quality and is costly The removal of mealybugs from naturally infested capsicums was measured after high pressure water washing at 50 75 100 125 150 175 or 200 psi and compared with results from an untreated control Before treatment capsicums had an average of 1237 live mealybugs per fruit At 3 days after high pressure waterwashing the numbers of live mealybugs on treated capsicums ranged from 38 to 118 per fruit resulting in 5885 reduction This compared with an average of 44 mealybugs on untreated capsicums at 3 days after treatment

Imidacloprid Applied Through Drip Irrigation as a New Promising Alternative to Control Mealybugs in Tunisian VineyardsMealybugs are serious insect pests in Tunisian vineyards where they can cause major production losses. Thus, a management program of these insects is a priority for grape growers. A summer pesticide trial was conducted in a vineyard, located in the Cap-Bon Region of Tunisia. The trial was carried out to assess the use of imidacloprid, a systemic insecticide, against mealybugs on vine. Imidacloprid was applied through the drip irrigation system for each vine and was then compared to methidathion, a contact insecticide. Imidacloprid was found to be more effective than methidathion on all mealybug developmental stages. In addition to its outstanding, up to 100% efficiency, imidacloprid provided an interesting long-term control of mealybugs. No significant difference was found between the two imidacloprid rates (1 and 2 ml/vine). Methidathion generated an overall low to intermediate efficacy on mealybugs and was more effective on both first instar nymphs and adult females than on the other mealybug developmental stages. Thus, imidacloprid applied through a drip irrigation system is a new promising option to control mealybugs in vineyards. For this reason it can be employed in an integrated management program against these pests in the Tunisian grape-growing area.

Planococcus ficus (Signoret) and Pseudococcus comstocki (Kuwana) (Hemiptera: Pseudococcidae) are economically important pests occurring in vineyards, causing severe economic losses for growers and compromising bunch production. The partial effectiveness of insecticides used in controlling mealybug infestations as well as their high impact on the environment and on human health have led to the research of alternative and sustainable control methods, including biological control. Several natural enemies are reported to be effective against mealybugs, but their activity may be hindered by tending ants. These social insects are known to exhibit a mutualistic relationship with mealybugs, resulting in extremely aggressive behavior against beneficial insects. Consequently, this study explored a method to mitigate ant attendance by means of sugar dispensers in order to improve ecosystem services, as well as decrease mealybug infestation in vineyards. Field trials were carried out in four commercial vineyards of Northern Italy infested by mealybugs, in which Anagyrus vladimiri Triapitsyn (Hymenoptera: Encyrtidae) and Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae) were released as biological control agents. Our results showed that sugar dispensers reduced ant activity and mealybug infestation, leading to a significant enhancement of ecosystem services. The technique showed a great potential in boosting biological control against mealybugs in field conditions, though the field application seemed to be labour intensive and needs to be replicated for a multi-year evaluation.

Three species of mealybug are major pests on a wide range of horticultural crops in New Zealand Pseudococcus longispinus P calceolariae and P viburni They can be found throughout New Zealand although they rarely become pests south of Marlborough Because colonies often establish in the calyx and stem of developing fruit they can cause rejection of export fruit During the 2008 Nelson apple harvest an increase in mealybug numbers was recorded for some commercial orchards A sample of 58 mealybuginfested apples was kept in a climate chamber at 20C to determine if any parasitoids were present From these 16 Tectracnemoidea sydneyensis (Hym Encyrtidae) and two Coccophagus gurneyi (Hym Aphelinidae) parasitoids were reared The following season 5400 fruit were examined from an infested block to determine mealybug species and the level of fruit infestation 188 of the fruit were infested 155 by P longispinus and 1 by P calceolariae Another 89 infested fruit were kept in individual containers at 20C From this sample 308 mealybugs were counted of which 305 were P longispinus and three were P calceolariae Fifteen percent of the P longispinus were parasitised by T sydneyensis Results from this study confirmed that P longispinus was the predominant mealybug species and that T sydneyensis was the most common parasitoid

The key insect pests of Actinidia arguta kiwifruit were determined by monitoring tagged fruit bunches for insects and insect damage in six orchard blocks from fruit set in November 2007 until harvest in February 2008 and by examining samples of picked fruit at harvest The proportion of fruit damaged by leafroller feeding increased throughout the entire growing season and live caterpillars were present on picked fruit at harvest Greenhouse thrips damage to fruit was noticeable from mid January Armoured scale insects and mealybugs were recorded on the fruit from December but most infestations occurred during the month prior to harvest Leafrollers and greenhouse thrips are the key production pests while leafrollers greedy scale and some mealybug species are potential quarantine species All three commercial A arguta cultivars grown in the Bay of Plenty are susceptible to the key pest species

Taiwan’s economy mainly relies on the export of agricultural products. If even the suspicion of a pest is found in the crop products after they are exported, not only are the agricultural products returned but the whole batch of crops is destroyed, resulting in extreme crop losses. The species of mealybugs, Coccidae, and Diaspididae, which are the primary pests of the scale insect in Taiwan, can not only lead to serious damage to the plants but also severely affect agricultural production. Hence, to recognize the scale pests is an important task in Taiwan’s agricultural field. In this study, we propose an AI-based pest detection system for solving the specific issue of detection of scale pests based on pictures. Deep-learning-based object detection models, such as faster region-based convolutional networks (Faster R-CNNs), single-shot multibox detectors (SSDs), and You Only Look Once v4 (YOLO v4), are employed to detect and localize scale pests in the picture. The experimental results show that YOLO v4 achieved the highest classification accuracy among the algorithms, with 100% in mealybugs, 89% in Coccidae, and 97% in Diaspididae. Meanwhile, the computational performance of YOLO v4 has indicated that it is suitable for real-time application. Moreover, the inference results of the YOLO v4 model further help the end user. A mobile application using the trained scale pest recognition model has been developed to facilitate pest identification in farms, which is helpful in applying appropriate pesticides to reduce crop losses.

Grapevine leafrollassociated Virus 3 debilitates grapevines reducing yields and juice quality and eventually makes vineyards uneconomic Mealybugs (Pseudococcus spp) are the key insect pests of grapes in New Zealand because they are the principal vectors of this virus Until recently all insecticides registered for their control depended on direct contact but mealybugs live in hardtotreat parts of vines This research tested the efficacy of two neonicotinoid insecticides imidacloprid and SCAL 5085 that have translaminar and systemic activity Two field trials were conducted on commercial vineyards with the insecticides applied as soil drenches In the first trial imidacloprid applied at 0525 g ai/vine reduced mealybug abundance by >99 compared with untreated vines and autumn and spring applications were equally effective Half this rate was less effective although drenching in autumn was better than in spring In the second trial treatments were applied in winter and SCAL 5085 at 0263 g ai/vine provided equivalent control to imidacloprid at 0525 g ai/vine

Mealybugs (Hemiptera Pseudococcidae) are the most important insect pests in New Zealand vineyards because they vector grapevine leafroll virus which seriously debilitates vines and reduces wine quality A field trial was conducted on a commercial vineyard using the insecticides prothiofos (Tokuthion) and buprofezin (Applaudtrade;) Factors tested were the timing and number of applications water rate (250 500 or 1000 litres/ha) and inclusion of an alkylsilicone or organosilicone spreadertype adjuvant Prothiofos was applied in late September (late dormant) while buprofezin was sprayed at late dormant mid October and late November (preflowering) The best treatments for reducing mealybug numbers and proportion of infested leaves were prothiofos at late dormant and two later applications of buprofezin Two applications of buprofezin were more effective than one more than halving the number of mealybugs A water rate of 500 litres/ha was equally as effective as 1000 litres/ha None of the three adjuvants improved the efficacy of prothiofos or buprofezin

Low oxygen and/or generally recognised as safe (GRAS)/food additive (FA) treatments in combination with cool storage have the potential to disinfest a range of commodities of various pests This paper reports on research to determine the tolerance of second/third and fifth instar codling moth larvae fifth instar lightbrown apple moth larvae mixed stages of greedy scale and obscure mealybugs and diapausing twospotted mite adults to ultra low oxygen (ULO lt;05 O2) and ULO combined with two GRAS/ FA compounds ethyl acetate and ethyl formate ULO alone did not consistently enhance mortality of these pests compared with air cool storage However addition of 30005000 ppm of ethyl acetate or ethyl formate reduced the time taken to achieve 99 mortality from weeks or months to between 8 h and 5 days depending on the pest

Ethyl formate (EF) is a generally recognised as safe (GRAS) compound that can be applied as a fumigant to disinfest fresh produce This paper reports initial research to determine the dose responses of various pests to ethyl formatecarbon dioxide treatment during 1 2 3 and 4h treatments at ambient temperatures between 18 and 23C Thrips (mixtures of Thrips tabaci and Frankliniella occidentalis) on lupin flowers obscure mealybugs (Pseudococcus viburni) on potatoes and greedy scale (Hemiberlesia rapax) on potatoes were more susceptible than either lightbrown apple moth (Epiphyas postvittana) eggs on plastic and fifth instar larvae on apples or codling moth (Cydia pomonella) second/ third instars and fifth instars on apples Further efficacy studies are warranted to investigate the commercial viability of EFCO2 treatment of fresh produce against other pests effects on fruit quality and commercial application logistics

Thesis (M.S.)--West Virginia University, 2009.
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Thesis (MScAgric (Conservation Ecology and Entomology)--University of Stellenbosch, 2009.
ENGLISH ABSTRACT: The obscure mealybug, Pseudococcus viburni (Signoret) (Pseudococcidae), is one of the common and serious pests of apples and pears in South Africa. The management of this pest in South Africa is dominated by the use of insecticides, while research into using natural enemies for biological control of mealybugs is still ongoing. Increasing concern over the environmental impact, pesticide residues in fruits, resistance, and expense associated with frequent use of insecticides make it necessary to investigate alternative biological control methods, such as the use of entomopathogenic nematodes, for the control of mealybugs. Entomopathogenic nematodes have proven comparable or even superior to chemicals in controlling certain insect pests, without residue problems or a harmful effect on the environment. An important aspect of using endemic nematodes includes the identification of species of nematodes and their symbiotic bacterial cells. A study was carried out to describe a new species of Steinernema, which was recovered during a previous survey in citrus orchards in three provinces of South Africa. Morphometrics, morphology, crossbreeding, drawings, light microscopy and Scanning Electron Microscopy (SEM) photographs were used to describe the new species. A cryopreservation method has been simplified and optimised for the long-term storage of Steinernema khoisanae (SF87) and Heterorhabditis zealandica (J34). Different cryoprotectants used included 15% glycerol, 8% ethylene glycol and 8% dimethyl sulfoxide (DMSO), in which S. khoisanae was incubated at room temperature for periods of two, three, four and five days, followed by a methanol wash. An optimum survival rate of 69% was obtained for S. khoisanae after a four-day incubation period in 15% glycerol. This technique has been used for the cryopreservation of H. zealandica, with a 78% survival rate. The thawed nematodes of both species were able to infect Galleria mellonella larvae after 42 days of cryopreservation (-196ºC) and were able to complete their life cycles.
AFRIKAANSE OPSOMMING: Die ligrooswitluis, Pseudococcus viburni (Signoret) (Pseudococcidae), is een van die algemene en ernstige peste van appels en pere in Suid-Afrika. Die bestuur van hierdie pes word tans in Suid-Afrika deur die gebruik van insekdoders gedomineer terwyl navorsing oor die gebruik van natuurlike vyande vir die beheer van P. viburni nog aan die gang is. Die verhoogde kommer oor die omgewing, residue in vrugte, weerstand, en die koste verbonde aan die gereelde gebruik van chemiese middels maak dit nodig om alternatiewe biologiese metodes van beheer, soos die gebruik van entomopatogeniese nematodes vir die beheer van witluis, te ondersoek. In ander lande is reeds aangetoon dat entomopatogeniese nematodes onder sekere omstandighede en vir sekere insekte gelykwaardige of selfs beter beheer kan gee as chemiese middels. ʼn Belangrike aspek van die gebruik van endemiese nematodes vir die beheer van insekte sluit die korrekte identifikasie van die spesies met hul geassosieerde bakteriese simbionte in. ʼn Nuwe spesie van Steinernema is uit ʼn vorige opname van entomopatogeniese nematodes in sitrusboorde in drie provinsies van Suid-Afrika geïsoleer. Morfometrie, morfologie, kruisteling, ligmikroskoop en SEM fotografie is gebruik om ʼn nuwe spesies te beskryf. ʼn Kriopreserveringsmetode is ontwikkel en ge-optimaliseer vir die langtermyn bewaring van Steinernema khoisanae (SF87) en Heterorhabditis zealandica (J34). Verskillende kriobeskermingsmiddels insluitend 15% gliserol, 8% dimetiel sulfokied (DMSO) en 8% etileen glikol, waarin S. khoisanae vir periodes van twee, drie, vier, en vyf dae geïnkubeer is, is teen kamertemperatuur, getoets, gevolg deur ʼn metanolbad. Optimum oorlewing van 69% is verkry vir S. khoisanae nadat die infektiewe larwes (IJ) vir vier dae in 15% gliserol gehou is. Hierdie tegniek is ook toegepas op H. zealandica, met 78% oorlewing van die IJ. Die ontvriesde nematodes van beide spesies was in staat om Galleria mellonella larwes suksesvol te infekteer en hulle lewensiklus te voltooi nadat hulle vir 45 dae onder kriopreservering gehou is teen -196ºC.

The use of entomopathogenic fungi to control agriculturally important pests, both in greenhouses and in the field, has been demonstrated by various authors for a number of years. This has been brought about by the development of resistance in certain pest species to chemical applications and a growing public awareness of the safety implications of residual insecticides. Several entomopathogenic fungi were tested against four insect pests found in the Republic of South Africa (RSA), the greenhouse whitefly, Trialeurodes vaporariorum, the rice weevil, Sitophilus oryzae, the grapevine mealybug, Planococcusficus and the sugarcane stem borer, Eldana saccharina. Further concentration, temperature and humidity studies were conducted with selected isolates on the rice weevil, S. oryzae. Sitophilus oryzae is considered one ofthe most important pests of stored grain. Several fungal isolates were tested against the rice weevil, four of which, B1, PPRI 6690, PPRI 6864 and PPRI 7067, were selected for further testing based on the mortality results over a 21 d period. Varying conidial concentrations were applied and at high doses of 1x10 -6 conidia ml -1 with mortality rates of to 84% achieved. LT 50 values ranged from 6 - 68d. Increased spore concentration resulted in an increase in overall mortality. Temperature and humidity was found to affect the infection potential of the four isolates tested. Four temperatures ranging from 15 - 30°C were tested. The highest mortality rates were obtained at 25°C where mortality ranged from 46 - 65% in 14d. Mortality rates decreased with decreasing temperature, and no mortality was recorded at 30°C. Temperature was found to significantly alter the LT 50 values, increasing the LT 50 with decreasing temperatures. Decreasing the humidity resulted in an increased LT 50 and a reduction in the overall mortality rates. The mortality of S. oryzae ranged according to the RH and isolate. Isolates Bland PPRI 6690 resulted in the highest mortalities of 80 and 83% at 92.5% RH, with LT 50's of 6.3d and 6.4d, respectively. Several entomopathogenic fungi were tested against T vaporariorum, P. ficus and E. saccharina, three key pests of South African crops. Nine fungal isolates were tested against the greenhouse whitefly, T vaporariorum, with mortalities ranging from 26.7 - 74.7% over 14d. Beauveria bassiana Isolates Bl and PPRl 6690 produced the highest mortality rates and were recommended for further pathogenicity testing against T. vaporariorum. Planococcus ficus is a common pest ofvineyards in the Western Cape Province, South Africa. Nine entomopathogenic fungi were screened against P.ficus, only two of which produced mortality. Eldana saccharina is a stalk borer, which infests sugarcane in large areas of Southern Africa. Five isolates were tested against second and third instar larvae, three of which, B1, PPRl 6864 and PPRl 6690 resulted in mortalities. Mean percentage mortality was low for all three isolates. From the study it was evident that two of the isolates tested, Bland PPRI 6690 (B. bassiana), showed potential against three of the four pests, and two isolates of Lecanicillium lecanii caused mortality in P. ficus. Further research and understanding of the effect of environmental conditions, spore concentration and epizootic potential would result in the further development of these isolates as future biological control agents.
Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.