Showing papers on "Aphididae published in 1983"
TL;DR: The failure of A. ervi to respond to either nettle aphids, Microlophium carnosum (Bukt.), or nettle leaves, despite its frequent parasitization of this aphid in the field, suggests the existence of more than one race of the parasitoid and casts doubts on the usefulness of alternative hosts as reservoirs for A. _ervi in integrated control programmes.
Abstract: . A Y-tube olfactometer was used to test the reactions of the hymenopteran cereal aphid parasitoids Aphidius uzbekistanicus Luzhetski and A. ervi Haliday to odours from aphids and their host plants. Only females responded to aphids but both sexes responded to plant odours. A. uzbekistanicus responded to the cereal aphids Sitobion avenae (F.) and Metopolophium dirhodum (Walker) whilst A. ervi, which has a broad host range, responded to M. dirhodum and the pea aphid, Acyrthosiphon pisum. Female A. uzbekistanicus responded to wheat leaves only but males responded to a range of plant material. Both male and female A. ervi responded to wheat and bean leaves. The failure of A. ervi to respond to either nettle aphids, Microlophium carnosum (Bukt.), or nettle leaves, despite its frequent parasitization of this aphid in the field, suggests the existence of more than one race of the parasitoid and casts doubts on the usefulness of alternative hosts as reservoirs for A. ervi in integrated control programmes. Males of both species responded to their respective females suggesting the presence of a sex specific attractant.
94 citations
TL;DR: One–dimensional slab polyacrylamide gel electrophoretic techniques, staining systems and isoenzyme banding patterns for 14 soluble enzymes separated from crude homogenates of individuals of six species of cereal aphids, finding the enzymes found to be most useful for inter–generic and/or -specific separations.
Abstract: One–dimensional slab polyacrylamide gel electrophoretic techniques, staining systems and isoenzyme banding patterns for 14 soluble enzymes separated from crude homogenates of individuals of six species of cereal aphids (Sitobion avenae (F.), S. fragariae (Wlk.), Metopolophium dirhodum (Wlk.), M. festucae (Theo.), Rhopalosiphum padi (L.) and R. maidis (Fitch)) are described. The value of the techniques and banding patterns to taxonomic and population genetic studies of these and other aphid species are briefly discussed. With the six species, it was possible to separate the different genera as well as individual species within genera. The enzymes found to be most useful for inter–generic and/or -specific separations were adenylate kinase (AK), esterase (EST), glucose-6-phosphate dehydrogenase (G-6-PDH), hexokinase (HK), malate dehydrogenase (MDH), peptidase (PEP), phosphatase (PHOS), phosphoglucomutase (PMG), 6-phosphogluconate dehydrogenase (6-PGD) and sorbitol dehydrogenase (SORDH), whilst glutamate oxaloacetate transaminase (GOT), α-glycerophosphate dehydrogenase (α-GPD), malic enzyme (ME) and peroxidase (POD) were of relatively little taxonomic use. There were no banding pattern differences between the various morphs of S. avenae (first to fourth-instar nymphs, apterous and alate adults using the 14 enzymes.
86 citations
TL;DR: On guava trees at Nelspruit, South Africa, there was a mutualism between the ant Anoplolepis custodiens and the mealybug Planococcus citri (Risso), which raised the population levels of both, but the ant population declined and the ant–homopteran mutualisms, although severely hit by the epizootic, nevertheless remained intact.
Abstract: On guava trees at Nelspruit, South Africa, there was a mutualism between the ant Anoplolepis custodiens (F. Sm.) and the mealybug Planococcus citri (Risso), which raised the population levels of both. When ants were excluded from half the trees, their overall population level also dropped by half. Further, they moved their nests to be as near as possible to their main food source, the honeydew of the mealybugs. When deprived of their ant mutualists, the mealybugs were heavily preyed on by coccinellids such as the ant–intolerant Exochomus flavipes (Thnb.) and the ant–tolerant Scymnus spp. Later, the mealybugs were almost totally eliminated by the primary entomogenous fungus Cladosporium sp. near C. oxysporum. The coccinellids, now without food, were forced to abandon the trees. In contrast, in trees where ants were allowed to continue their normal activity, the epizootic among the mealybugs was delayed by 14 days. This limitation by the ants of disease allowed a basal but fragmented mealybug population to survive. As the mealybugs declined, the ants switched to attending the aphid Aphis gossypii Glov. Fifteen days after the epizootic struck the ant–attended mealybug population, it began to devastate the aphid population. With both mealybugs and aphids at a low level, the ant population declined. However, the ant–homopteran mutualisms, although severely hit by the epizootic, nevertheless remained intact.
38 citations
TL;DR: A presence-absence sequential sampling plan was developed for Brussels sprouts which incorporates the between-plant clumping behavior of cabbage aphid and green peach aphid, and tentative control decision thresholds are proposed for the respective aphid species.
Abstract: J. Econ. Entomol. 76: 476479 (1983) ABSTRACT A presence-absence sequential sampling plan. which incorporates the between-plant clumping behavior of cabbage aphid and green peach aphid, was developed for Brussels sprouts. Tentative control decision thresholds are proposed for the respective aphid species. The distribution pattern of cabbage aphid is much more clumped. as indicated by much higher density of insects for ;I given proportion of infested plants. Approximately 2,200 ha of Brussels sprouts, Brcissictr oleracea gemmiferci, are grown in California, with the major areas of production centered in Santa Cruz and Monterey Counties (Anonymous 1981). Four of the more common insect pests of Brussels sprouts in these areas are the cabbage maggot, Hylemyi brassictie (Wiede- mann), the seed corn maggot, Hylemya platura (Mei- gen), the cabbage aphid, Brevicoryne brassiccre (L.), and the green peach aphid, Myzuspersicae (Sulzer). The cabbage maggot and the seed corn maggot are normally only a problem during the seedling stage when stands are established from transplants. The cabbage aphid can
37 citations
TL;DR: Esterase was found to be the best enzyme for taxonomic differentiation of all aphidiid species examined and the use of electrophoresis for assessing percentage wasp parasitism in integrated management studies of cereal aphids is discussed.
Abstract: The effect of parasitism by the aphidiid wasp Aphidius uzbekistanicus (Luzhetski) on the isoenzyme banding patterns of 14 soluble enzymes separated by one–dimensional slab polyacrylamide gel electrophoresis from crude homogenates of its main host, Sitobion avenae (F), are described Parasitism was found to be detectable using any 12 of these enzymes The differences observed between the banding patterns for three enzymes (ester–ase, malate dehydrogenase and malic enzyme) separated from the adults of five primary parasitoid species attacking this aphid ( A picipes (Nees), A uzbekistanicus, Ephedrus plagiator (Nees) Praon volucre (Hal) and Toxares deltiger (Hal)) are also described Esterase was found to be the best enzyme for taxonomic differentiation of all aphidiid species examined The use of electrophoresis for assessing percentage wasp parasitism in integrated management studies of cereal aphids is discussed
35 citations
TL;DR: The relationships between the form and possible functions of the wax are discussed in the light of the results, as is the degree of correlation between its morphology and current opinion concerning the classification of the family.
Abstract: Summary The visible wax coatings of nine species of Aphididae, distributed through six tribes in four subfamilies, are examined by means of the Scanning Electron Microscope. The micromorphology of the extrusions is described and illustrated, as are the cuticular specializations via which the coatings are constructed. The relationships between the form and possible functions of the wax are discussed in the light of the results, as is the degree of correlation between its morphology and current opinion concerning the classification of the family.
33 citations
TL;DR: The effects of three insecticides on a guild of natural enemies and their prey were determined in the laboratory, particularly the possibility that different insecticides might be used to differentially kill selected groups of predators, their prey in the field, or both.
Abstract: The effects of three insecticides on a guild of natural enemies and their prey were determined in the laboratory. The cereal aphid Meropolophium dirhodium Walker (Hemiptera: Aphididae) and six potentially important predators were exposed to dry insecticide films for 24 h. after which time they were examined and recorded as alive, moribund, or dead. The insecticides tested were pirimicarb, cypermethrin, and methyl parathion. The predators tested were the insects Coccinella septempunctata L. (Coleoptera: Coccinellidae), Syrphus spp. (Diptera: Syrphidae), Pterostichus melanarius Illiger (Coleoptera: Carabidae). Nebria brevicollis F. (Coleoptera: Carabidae). Agonum dorsale Pont. (Coleoptera: Carabidae), and spiders, Erigone spp. (Araneae: Linyphiidae). Methyl parathion was overall the most toxic compound. cypermethrin was less toxic, and pirimicarb was the least toxic. The relative susceptibility of the predators and the aphid varied considerably between insecticides, as did the slope of the dose-response curve. We discuss our data in the light of these findings, particularly the possibility that different insecticides might be used to differentially kill selected groups of predators, their prey in the field, or both.
28 citations
27 citations
TL;DR: The biology and economic status of aphids attacking rice throughout the world is reviewed, as is the literature concerning other aphids found in or near irrigated rice fields but not usually infesting rice, and 37 species of aphid belonging to seventeen genera are considered.
Abstract: The biology and economic status of aphids attacking rice throughout the world is reviewed, as is the literature concerning other aphids found in or near irrigated rice fields but not usually infesting rice. Altogether, 37 species of aphids belonging to seventeen genera are considered. The aphids are dealt with in two similar–sized groups according to their feeding sites, namely root–feeding and leaf–, stem– and ear–feeding species. Aphis craccivora Koch and Myzus persicae (Sulz.) are regarded as ‘occasional rice aphids’ as they are found on rice occasionally but do not regularly infest rice plants. A. gossypu Glov. is treated as a ‘rice aphid’ although its occurrence on rice plants is also sporadic. In addition to the literature survey, additional information is given based on field collections and observations, on the rice aphid component of more than 18 000 aphids trapped in yellow pan traps, on the natural enemies reared and collected and from laboratory experiments in Japan. Unpubished information was also extracted from the data labels of the British Museum (Natural History) aphid collection. The ecological relationships between rice aphids and aphids associated with weeds near irrigated rice fields in the Yamaguchi area of Japan is discussed. Three of the rice aphids were found on 22 species of weeds and the three ‘occasional rice aphids’ also occured on 22 species of weeds. A total of 43 species of weeds harboured aphids.
25 citations
TL;DR: Stand management in lucerne (Medicago sativa) was used to conserve natural enemies and reduce overwintering aphid numbers and the place of pirimicarb as a selective aphicide in integrated programmes was confirmed.
Abstract: Stand management in lucerne (Medicago sativa) was used to conserve natural enemies and reduce overwintering aphid (Acyrthosiphon kondoi and A pisum) numbers Comparison of stem and sweep net counts allowed sweep counts of predators to be calibrated, and showed that the parasite, Aphidius eadyi, and the predator, Micromus tasmaniae, were best synchronised with lucerne aphid populations Lucerne reservoirs created by strip-cutting or strip-grazing were associated with lower aphid populations and lower ratios of aphids:predators, except in spring Laboratory-bred parasites were released to augment early spring populations, but slow dispersal reduced their impact Winter grazing and herbicide treatment significantly reduced aphid populations in spring Insecticide trials confirmed the place of pirimicarb as a selective aphicide in integrated programmes
23 citations
TL;DR: Production of sexuales by wingless and winged individuals of the pea aphid Acyrthosiphon pisum (Harris) was monitored at two constant temperatures and a series of photoperiods using three different clones to determine the proportion of males among total offspring of wingless parents.
Abstract: Production of sexuales by wingless and winged individuals of the pea aphid Acyrthosiphon pisum (Harris) was monitored at two constant temperatures and a series of photoperiods using three different...
TL;DR: It is proposed that prior to the introduction of T. curvicaudus, the aphid's major limiting factor was the occurrence of mean daily temperatures above 22°C, which constituted the facteur essentiel limitant the populations of ce puceron.
Abstract: Trioxys curvicaudus Mackauer, an introduced parasitoid which had already proven successful in bringing the linden aphid,Eucallipterus tiliae L., under biological control in Berkeley, Calif., was released in 1978 in San Jose, Calif., where the aphid was still a pest. Recovery of the parasitoid was made later the same season. Monitoring and dissection studies ofE. tiliae in 1979 and 1980 demonstrated thatT. curvicaudus had become established in San Jose and was exerting a controlling influence on the aphid. Native natural enemies did not appear to have any appreciable effect on aphid numbers. It is proposed that prior to the introduction ofT. curvicaudus, the aphid's major limiting factor was the occurrence of mean daily temperatures above 22°C.
TL;DR: The most severe aphid outbreak in the 5 years of this study resulted from survival of large numbers of spotted alfalfa aphids through the unusually warm, dry winter of 1980–1981 and the potential for more widespread outbreaks of this species has not yet been determined.
Abstract: Since the so-called blue alfalfa aphid, Acyrthosiphon kondoi Shinji, was first identified in Oklahoma during 1977, extensive sampling programs have been conducted to determine the geographical and seasonal incidence of this species in relation to other aphid pests of alfalfa in the state. This aphid has now been found in 62 counties. Like the pea aphid, A. pisum (Harris), A. kondoi is a cool-season species which has been found primarily from April through June. Stunting of alfalfa due to A. kondoi infestations was observed in a total of 10 counties of central Oklahoma in March and April of 1980 and 1981. Because these infestations were confined to limited areas, the potential for more widespread outbreaks of this species has not yet been determined. From midsummer through fall, the spotted alfalfa aphid, Therioaphis maculata (Buckton), was often the only aphid species collected. The most severe aphid outbreak in the 5 years of this study resulted from survival of large numbers of spotted alfalfa aphids through the unusually warm, dry winterof 1980–1981. This species was associated with yield reductions and loss of stands throughout Oklahoma in the spring of 1981.
TL;DR: Field sampling of wheat aphids and their parasitoids showed that the green bug, Schizaphis graminum (Rondani), was the most abundant aphid species present, followed by the oat-bird cherry aphid, Rhopalosiphum Padi (L.).
Abstract: Field sampling of wheat aphids and their parasitoids showed that the green bug, Schizaphis graminum (Rondani), was the most abundant aphid species present, followed by the oat-bird cherry aphid, Rhopalosiphum Padi (L.). The primary parasitoids reared from greenbug, in order of abundance, were Lysiphlebus testaceipes (Cresson), Diaeretiella rapae (M’Intosh), and Aphelinus nigritus (Howard). The hyperparasitoids obtained, in order of abundance, were Alloxysta sp. ( megourae complex), Asaphes lucens (Provancher), and Pachyneuron siphonophorae (Ashmead). Samples taken in three separate wheat fields indicated that S. graminum and R. padi were distinctly aggregated. Collectively, the green bug parasitoids were distinctly aggregated and had a significant effect on the density of S. graminum within two of the three fields. Parasitoid distribution in the third field was near random, and no significant relationship was observed between numerical fluctuations of the greenbug and its parasitoids.
TL;DR: Various sampling schemes were evaluated for estimating the population size of the apple aphid, Aphis pomi DeGeer, on an apple tree and the method of counting the number of aphids on the most infested leaf provided the most accurate assessment of aphid density, but it required the most effort.
Abstract: Various sampling schemes were evaluated for estimating the population size of the apple aphid, Aphis pomi DeGeer, on an apple tree. More aphids were found to inhabit the actively growing shoots in the top of the tree canopy than the bottom. An average of 90% of the total aphid population occurred on the first six leaves at the top of the tree, whereas the first four leaves contained 90% of the aphids at the bottom for all sampling dates. The method of counting the number of aphids on the most infested leaf provided the most accurate assessment of aphid density, but it required the most effort. Counting only the number of infested leaves per shoot resulted in a decrease in accuracy, but also a 4- to 8-fold decrease in the time required to sample. Reliable estimates of the aphid population over an entire tree can be made from sampling only those areas of the tree reachable from the ground. Sample size estimates are presented on the number of shoots and trees to sample, as well as an estimate of precision.
TL;DR: The total browning potential test (TBP), a modification of the PPO assay, was developed for use in screening for aphid resistance and is rapid, inexpensive, and highly effective in identifying aphid resistant clones.
Abstract: Polyphenoloxidase (PPO) activity in the glandular trichomes of 32Solanum tuberosum ×S. berthaultii F3 hybrid clones differentially resistant to the green peach aphid,Myzus persicae (Sulzer) was determined. Within this population of segregating clones, aphid infestation levels varied 8-fold, while a 5-fold difference in glandular trichome PPO activity was observed. PPO activity and aphid resistance at three sample dates were correlated as follows: r = 0.38 (P = 0.05), r = 0.31 (P = 0.10), and r = 0.55 (P = 0.01), respectively. The total browning potential test (TBP), a modification of the PPO assay, was developed for use in screening for aphid resistance. The TBP procedure is rapid, inexpensive, and highly effective in identifying aphid resistant clones.
TL;DR: Development of resistance to carbaryl in field populations of the filbert aphid, Myzocallis coryli (Goetze), is reported here for the first time.
Abstract: Development of resistance to carbaryl in field populations of the filbert aphid, Myzocallis coryli (Goetze), is reported here for the first time. The log dosage mortality curves of three aphid populations with different carbaryl exposure history suggest that resistance was acquired in a relatively short time (4 to 5 years, perhaps sooner), but the degree of resistance increased as insecticide use was prolonged. Aphid populations exposed to carbaryl for 5 years (about nine sprays) required 17 to 22 times more chemicals to obtain mortality similar to that of the susceptible strain. The population exposed to carbaryl for 20 years (45 sprays) required about 78 to 145 times more chemical than did the susceptible strain. Resistant aphids attempted to avoid insecticide residues more vigorously than did the susceptible aphids, suggesting that insecticide avoidance behavior might be involved in this resistance mechanism.
TL;DR: Resistant segregates occurred in most of the entries tested, indicating that selection for germplasm improvement is possible in alfalfa lines or cultivars evaluated for resistance to the red form of Acyrthosiphon pisum.
Abstract: A red form of Acyrthosiphon pisum , (Harris) was collected from alfalfa at two locations in Maryland in 1979 to 1981. Twenty-two alfalfa lines or cultivars were evaluated for resistance to this form in laboratory tests for screening seedlings. Of the 19 lines or cultivars tested that have been classified as resistant to the green form of the pea aphid, only the lines BAA-15 and PA-1 and the cultivar ‘CUF-101’ exhibited high resistance to the red form. ‘Cascade,’ WL 219, WL 311, and WL 313 showed low resistance levels. Resistant segregates occurred in most of the entries tested, indicating that selection for germplasm improvement is possible.
TL;DR: The seasonal abundance of aphids in winter wheat and barley was monitored in eastern Virginia during 1979–1980 and 1980–1981, and the English grain aphid, Macrosiphum Avenae (F.), was the most abundant species during the spring.
Abstract: The seasonal abundance of aphids in winter wheat and barley was monitored in eastern Virginia during 1979–1980 and 1980–1981. Significantly more aphids were observed in barley than in wheat. Population densities were significantly higher in the fall of 1979 than in 1980; however, the reverse was noted in springtime population levels. The heavy fall population, approaching 240 aphids per 0.3 row m. rapidly dropped in December 1979 after 8 consecutive days of subfreezing temperatures. The 1980–1981 season had below-normal temperatures in the fall, and populations never exceeded 82 aphids per 0.3 row-m until spring. In both years, aphid populations rapidly fell in May after several days of 27°C temperature and low humidity. The corn leaf aphid. Rhopalosiphum maidis (Fitch), was usually the most abundant species in the complex in autumn. The English grain aphid, Macrosiphum Avenae (F.), was the most abundant species during the spring. Rhopalosiphum padi (L.), and the green bug, Schizaphis graminum (Rondani), were relatively abundant throughout the entire growing season. Corn leaf aphids were not present in the spring. Ovoviviparous reproduction was observed in most months of the season, even at temperatures as low as 9° C.
01 Jan 1983
TL;DR: Adelgids in general have short 2–5 segmented antennae, with 2 primary rhinaria in apterae and 3 in alatae; the wings are usually held roof-like in repose and the cubitus 1 and 2 remain separate in the fore wing.
Abstract: The superfamily Aphidoidea includes three families Aphididae, Adelgidae and Phylloxeridae (the last family is not known from the Indian subregion. The Adelgidae (and Phylloxeridae) differ from the Aphididae in that both sexuales and parthenogenetic forms are oviparous (as opposed to viviparity in the parthenogenetic forms of Aphididae). The fore wing is devoid of radial sector, which is otherwise normally present in Aphididae. Adelgids in general have short 2–5 segmented antennae, with 2 primary rhinaria in apterae and 3 in alatae; the wings are usually held roof-like in repose and the cubitus 1 and 2 remain separate in the fore wing; siphunculi (evident in most Aphididae) are absent and cauda is not discernible. All adelgids are known to feed only on Coniferae and may have as many as 5 generations, while leading a heteroecious holocyclic life cycle (e.g. Picea-Abies), viz., fundatrix, gallicola (alata-migrans) sistines, progredious alatae (seupara) and apterae and sexuales, of which sexuales and...
TL;DR: The toxicity of insecticides was established for populations of Myzus persicae (Sulzer) collected from peppers in the autumn of most years from 1971 to 1980, and field tests indicated that the best control was achieved in recent years with acephate, methamidophos, profenofos, phorate, and aldicarb.
Abstract: The toxicity of insecticides was established for populations of Myzus persicae (Sulzer) collected from peppers in the autumn of most years from 1971 to 1980. Laboratory tests proved that green peach aphids were resistant to malathion in 1971, and resistance to three other insecticides was suspected. By 1980, resistance was recorded for 13 materials, and cross-resistance was suspected for three newer insecticides. LD95 values for susceptible aphids varied over a 4-fold range through the years. Field tests with contact sprays or systemic granular treatments indicated that the best control was achieved in recent years with acephate, methamidophos, profenofos, phorate, and aldicarb.
TL;DR: A generalized life cycle and biology of the morphs are described for Brachycolus asparagi Mordvilko, showing that their reproductive phase spanned most of their adult life and crowds of nymphal asparagus aphids increased wing production.
Abstract: A generalized life cycle and biology of the morphs are described for Brachycolus asparagi Mordvilko. Oviparae laid overwintering eggs on the asparagus ferns, Asparagus officinalis L., beginning in September. The eggs hatched in late March and developed into fundatrices that established themselves on the emerging asparagus spears. A fundatrix gives birth to about 18 nymphs, as compared with 54 nymphs for an apterous virginopara. In summer, the apterous morph had a 33.5% higher intrinsic rate of increase than the alate morph. Crowding of nymphal asparagus aphids increased wing production. The fecundity curve for the apterous virginoparae peaked once, early in their reproductive phase, whereas the curve for the alate virginoparae peaked a number of times and showed that their reproductive phase spanned most of their adult life. A single sexupara could give birth to oviparae, as well as to male and virginoparous morphs. The oviparae produced an average of 10.5 eggs. Males were capable of multiple matings.
TL;DR: The aphids Dysaphis aucupariae (Buckton) and Pentalonia gavarri Eastop are recorded for the first time from Australia.
Abstract: The aphids Dysaphis aucupariae (Buckton) and Pentalonia gavarri Eastop are recorded for the first time from Australia. The Australian aphid fauna comprises about 140 known species (Eastop 1966a; Carver 1976, 1980; Anon. 1978), to which 2 more can now be added.
TL;DR: The spotted alfalfa aphid, Therioaphis trifolii (Monell) forma maculata, was recorded from New Zealand for the first time in April 1982 and survival and reproduction showed that the aphid preferred Medicago spp.
Abstract: The spotted alfalfa aphid, Therioaphis trifolii (Monell) forma maculata, was recorded from New Zealand for the first time in April 1982. The initial infestations are described with information on seasonal population variations. Its taxonomic status is examined in relation to morphology and host plant relationships. Survival and reproduction on 19 legume species and 4 lucerne cultivars were measured, and results showed that the aphid preferred Medicago spp., especially medicks. Glasshouse tests with artificially infested plants showed that Trifolium spp., with the exception of T. dubium and T. glomeratum, survived attack better than Medicago spp. Similar tests with lucerne cuItivars showed patterns of resistance which generally conformed to published information.