bluuebunny/crossref_metadata_2025_split huggingface dataset:
A multivariate analysis of growth and development parameters of the legume pod borer, Maruca testulalis on variably resistant cowpea cultivars
Authors: Oghiakhe S. , Odulaja A. 
Published: April 2011

AbstractPrincipal component analysis was employed to study the variation patterns in 18 cowpea cultivars developed for resistance to Maruca testulalis Geyer (Lepidoptera: Pyralidae) based on 7 developmental parameters of the pest on floral buds, flowers and sliced pods. On the whole, three developmental parameters: percentage pupation (V2), percentage emergence (V5) and growth index (V7) were the most important for the grouping of the cultivars with respect to M. testulalis damage. However, out of the three parameters, growth index (V7) had the highest factor score. Using the cluster analysis technique, the cultivars were sorted into five distinct groups for each part. The importance of these findings in the determination of protection periods for particular cultivars and cultural control studies of M. testulalis in cowpea are discussed.
Effect of plant water stress on honeydew production, weight gain and oviposition of brown planthopper Nilaparvata lugens on rice cultivars
Authors: Baqui M. A. , Kershaw W. J. S. 
Published: April 2011

AbstractGlasshouse studies were made on honeydew production, adult and nymphal body weight gain, fecundity and size of egg groups of brown planthopper Nilaparvata lugens (Stål) (Homoptera: Delphacidae) (BPH) on CVS TN1, ASD7, Babawee, Mudgo, Rathu‐Heenati and Ptb33 rice plants with watering regimes of 10 ml, 20 ml, 30 ml and excess water daily. Honeydew production, weight gain, fecundity and size of egg groups were greatest on TN1, followed by ASD7. BPH did less well on Babawee, Mudgo and Rathu‐Heenati and they did worst on Ptb33. Watering regimes greatly affected performance, with significantly less honeydew, less weight gain, lower fecundity and smaller egg groups on plants with 10 ml water daily than on plants with excess water. The 20 ml and 30 ml watering regimes also significantly reduced honeydew production on TN1 and ASD7 and fecundity and weight gain of adults and nymphs on Mudgo. On Babawee adults gained most weight on the 20 ml and 30 ml treatments, and nymphs gained most weight on the 30 ml treatment. BPH laid most eggs on TN1, ASD7, Babawee and Rathu‐Heenati when plants were given 30 ml water daily.
Management of a German cockroach population with a juvenoid bait formulation: computer simulation
Authors: Zeman P. 
Published: April 2011

AbstractA computer model was applied to simulate responses of German cockroach populations to feeding on juvenoid baits during an equilibrium, exponential, and the earliest phase of population growth. The simulations show that the renewal potential of the cockroach populations will be exhausted when about 80% or more adults become sterile. The attainment of this activity threshold will be preceded by a lag time with no apparent control effect. The time delay appears substantially shorter for both growing populations (30–60 days) than for the equilibrious one (90–120 days), but, the former ones will continue growing throughout this lag. The simulations predict that even a worse baits' performance can give sufficient control effect in the field if the baits are laid in an early phase of population growth. Thus, optimum tactics should integrate administration of juvenoid baits with an introductory reduction of cockroach population.
Effects of host plant leaf damage on cabbage looper moth attraction and oviposition
Authors: Landolt P. J. 
Published: April 2011

AbstractMated female Trichoplusia ni (Hubner) moths, when presented a choice of either undamaged cotton plants, Gossypium hirsutum L., or damaged plants (cut leaves or feeding T. ni larvae) in a flight tunnel, were most often attracted first to the damaged plants. However, these same moths oviposited primarily on the undamaged plants. In a similar test with cabbage plants, Brassica oleracea L., the presence of conspecific larvae decreased both attraction and oviposition. Cuts to cabbage leaves had no significant effect on attraction or oviposition. When presented one plant at a time, percentages of cabbage looper moths attracted were not affected by the presence of larvae on either cabbage or cotton plants, or by cuts to cabbage plant leaves. Percentages of moths attracted were, however, higher using cotton plants with cut leaves. The results suggest an important role for damage induced plant volatiles in host location as well as host acceptance by T. ni.
Influence of developmental conditions on cold‐hardiness of adult Dalbulus leafhoppers: implications for overwintering
Authors: Larsen K. J. , Lee R. E. , Nault L. R. 
Published: April 2011

AbstractLittle is known about how adults of the corn leafhopper, Dalbulus maidis (DeLong & Wolcott), and its congeners survive subfreezing temperatures at high elevations during the dry winter in Mexico. In the laboratory, duration of survival at −5 °C was measured for four Mexican Dalbulus species: D. maidis, D. elimatus (Ball), D. gelbus DeLong and D. quinquenotatus DeLong & Nault; and a closely related North American species, Baldulus tripsaci Kramer & Whitcomb. Adult leafhoppers reared under environmental conditions that simulated the beginning of the dry winter season during October in Mexico (‘October‐reared’) were at least twice as tolerant of −5 °C than adults reared under environmental conditions that simulated the beginning of the wet summer season during June (‘June‐reared’). Dalbulus species found primarily at high elevations, such as D. elimatus, were seven times more tolerant of −5 °C than D. quinquenotatus, a species which overwinters at low to mid elevations on its Tripsacum hosts. October‐reared D. maidis adults survived relatively short periods at −5 °C (LT50 = 8.9 h) compared to October‐reared D. elimatus adults (LT50 = 42.3 h). This suggests that in Mexico, D. maidis either overwinters in protected habitats at higher elevations or it migrates to lower, frost‐free regions. October‐reared B. tripsaci adults, which overwinter in the egg stage, were intolerant of −5 °C (LT50 = 2.6 h). A conditioning period for 1 h at +5 °C before and after exposure to −5 °C significantly improved survival for D. maidis. Supercooling points (SCPs) were between −23 and −20 °C, indicating that mortality of these leafhoppers at −5 °C was due to cold shock injury rather than internal ice formation.
Larval performance of two leafroller species on known and potential hosts
Authors: Smirle M. J. 
Published: April 2011

AbstractTwo univoltine leafroller species, Archips argyrospila Walker and Archips rosana L., were reared from eclosion to adulthood on known or potential host plants. Both species were able to complete development on eight of the ten plants tested, the exceptions being apricot and peach. Rates of development differed among hosts, and indicated a range of host suitability. Differences in female pupal weights were apparent following the different rearing treatments, but these did not correlate with subsequent female fecundity. When development was compared between the two leafroller species, A. rosana had higher survivorship, more rapid development and higher female fecundity than did A. argyrospila, regardless of host. These findings indicate that A. rosana may successfully exploit a wider host range than does A. argyrospila. Comparisons of survivorship and developmental rates among hosts for each species of leafroller suggest that both species may have the potential for host‐range expansion.
Conserving genetic variability of a wild insect population under laboratory conditions
Authors: Delpuech J‐M. , Carton Y. , Roush R. T. 
Published: April 2011

AbstractDrosophila melanogaster (Meigen) was used to test the power of isofemale lines in preserving genetic variability. We performed experiments in two ways. One series consisted of measuring the genetic variability for three enzymatic loci in 32 isofemale lines, in the first and 23rd generations of culture. In the second series, we tested the capacity of the larvae to eliminate a parasitoid by encapsulation after eight years of laboratory breeding. In general, individual isofemale lines appeared to change during the 23 generations of the study, but the global frequency of these alleles among the 32 isofemale lines stayed relatively unchanged. The only rare allele observed was also conserved. Changes in allozyme frequencies at any one locus were independent of those at other loci. Genetic variation of a biological trait, the capacity of the larvae to encapsulate a parasitoid, also changed, but it could be restored to a level close to that of the starting population by mass hybridizing together individuals of each line.RésuméD. melanogaster (Meigen) a été utiliseé pour tester la capacité des lignées isofemelles à conserver la variabiliteé génétique d'une population naturelle. Deux types d'expériences ont été réalisées. L'une a consisteé à déterminer la variabiliteé génétique de 3 locus enzymatiques pour 32 lignées isofemelles à la première et à la 23éme génération d'élevage au laboratoire. L'autre a consisté a tester la capacité des larves à éliminer un parasitoïde par le processus d'encapsulation après 8 années d'élevage au laboratoire. D'une façon générale, certaines lignées isofemelles perdent de la variabilité durant les 23 générations de l'étude. Mais la fréquence globale des allèles reste inchangée si l'on considère l'ensemble des 32 lignées. Le seul allèle rare observé a également été conservé. Les modifications des fréquences allèliques à chacun des locus ont lieu de façon indépendante les unes des autres. La variabilité génétique d'un caractère biologique, la capacité des larves à encapsuler le parasitoïde, a également varié, mais elle a pu être restaurée à un niveau proche de la population initiale en rassemblant plusieurs individus de chacune des lignées.
Responses of a compatible lucerne variety to attack by spotted alfalfa aphid: changes in the redox balance in affected tissues
Authors: Jiang Y. , Miles P. W. 
Published: April 2011

AbstractThe spotted alfalfa aphid, Therioaphis trifolii maculata (Buckton), caused local browning of cells surrounding feeding sites on lucerne plants (cv. Hunter River). Aqueous extracts of infested leaves underwent a marked browning process that did not occur in extracts of healthy leaves. The process was accelerated by addition of tyrosinase and peroxidase and reversed by reducing agents such as ascorbate and glutathione. In the presence of added reducing agents, the extracts produced brown precipitates, probably conjugates of phenolics with leaf proteins similar to those involved in the sealing of damaged tissues in vivo.Partially autoxidised catechin (PAC) solutions showed an absorbance peak at 438 nm that was increased by polyphenol oxidase and decreased by ascorbate and glutathione. When extraction of tissues into PAC was used to assess redox activities, healthy tissues showed a rapid, short lived oxidising activity combined with a much more persistent reducing activity, whereas infested leaves had even greater oxidising activity and no detectable reducing activity.Soluble phenolics increased in infested leaves and stems. Total protein decreased, but the specific activity of peroxidase, catechol oxidase and superoxide dismutase relative to protein content increased. The ability of extracts to reduce cytochrome c increased, indicating an overall increase in superoxide radicals in attacked tissues.These results are consistent with a general disturbance of redox balance induced in tissues by aphid feeding, including accumulation of oxidases and phenolic substrates and loss of reducing activity and protein.
Distribution of second generation European corn borer, Ostrinia nubilalis, egg masses in field corn and relationship to subsequent tunneling damage
Authors: Sorenson C. E. , Kennedy G. G. , Van Duyn J. W. , Bradley J. R. 
Published: April 2011

AbstractThe relationship between second generation European corn borer (Ostrinia nubilalis Hübner) egg mass numbers and subsequent field corn damage, as measured by stalk cavity numbers, was studied in 79 fields in northeastern North Carolina over three years. A mean of 0.028 egg masses per plant (645 egg masses/23400 plants) was found over the course of the study. Significant differences in oviposition rate were detected between fields and years. Ca. 85% of egg masses were deposited in a five leaf zone surrounding the primary ear; of these, 89% were found on the lower four leaves in this zone. Egg masses appeared to be distributed randomly within fields but at low rates of incidence, and oviposition was relatively uniform between sampling areas within individual fields. Under moderate to high oviposition pressure (mean number of egg masses per plant over the duration of the oviposition period >ca. 0.02), eggs laid during the early phases of the oviposition period account for more subsequent stalk damage than eggs laid during the later phases of the oviposition period. Variations in second generation egg mass numbers accounted for ca. 70% of variation in stalk cavity numbers.
Ovipositional preference of Siphoninus phillyreae and its fitness on seven host plant species
Authors: Leddy Paula M. , Paine Timothy D. , Bellows Thomas S. 
Published: April 2011

AbstractThe relationship between ovipositional preference of Siphoninus phillyreae (Haliday) (Homoptera: Aleyrodidae) and host plant suitability on seven host plant species (Citrus sinensis (L.) cv. ‘Washington’ [navel orange], Fraxinus uhdei (Wenz.) [shamel ash], Heteromeles arbutifolia Roemer [toyon], Malus domestica Mill. cv. ‘Granny Smith’ [apple], Pistacia vera L. cv. ‘Kerman’ [pistachio], Prunus persica (L.) cv. ‘O'Henry’ [peach], and Pyrus communis L. cv. ‘Bartlett’ [pear]) was evaluated. Ovipositional preference of S. phillyreae was determined by measuring egg density after adult female whiteflies were given a simultaneous choice of all host plants for oviposition. Immature survival, developmental time, and adult size were examined to determine host plant suitability for S. phillyreae. All studies were performed under greenhouse conditions. S. phillyreae showed distinct ovipositional preference among host plant species. Host plant species had a significant effect on immature survival, but little or no effect on developmental time or forewing length. For four of the seven host plant species tested, there was an association between ovipositional preference and survival.
Systemic antifeedant effects of azadirachtin on the peach‐potato aphid Myzus persicae
Authors: Nisbet A. J. , Woodford J. A. T. , Strang R. H. C. , Connolly J. D. 
Published: April 2011

AbstractThe electrical penetration graph (EPG) method was used to analyse the feeding behaviour of apterous, adult Myzus persicae (Sulzer) (Homoptera: Aphididae) on Nicotiana clevelandii (Gray) seedlings, treated systemically with azadirachtin. A preliminary experiment showed that the effects of tethering aphids for EPG recording were minimal. The percentage of the 9 h recording period devoted to non‐penetration activities, and to stylet pathway patterns increased as the azadirachtin concentration in the root treatment increased. The number of probes initiated, and the numbers of sieve tube penetrations also increased with increased azadirachtin concentration. The mean time elapsing between the initiation of the first probe to reach a sieve element and contact with this tissue was not significantly altered by azadirachtin treatment. However, azadirachtin treatment significantly reduced the percentage of probes that reached sieve elements and increased non‐penetration activity before and after the first period of ingestion from the sieve elements. The percentage of the recording period spent in the EPG pattern associated with sieve tube penetration was significantly reduced by an azadirachtin concentration of 300 ppm, and the duration of each individual penetration was significantly reduced by an azadirachtin concentration of 100 ppm. When the total EPG was split into 3 h periods, significant interactions were seen between time period and azadirachtin concentration for the duration of non‐penetration, pathway, and sieve tube penetration patterns.
Effects of a host plant, Brassica juncea, on calling behaviour and egg maturation in the diamondback moth, Plutella xylostella
Authors: Pittendrigh B. R. , Pivnick K. A. 
Published: April 2011

AbstractThe influence of the presence of seedlings of a host plant, Oriental mustard, Brassica juncea (L.) Coss., on the calling behaviour and egg maturation in the diamondback moth, Plutella xylostella (L.), was investigated. In the presence of plants, females began calling at a younger age, began calling earlier in the night, and spent more time calling. Females which were kept with plants until after their first night of calling and then were isolated from plants, subsequently called less, at a level not significantly different from females which had never been exposed to plants. Of all females, both with and without plants, which were dissected at the end of the first night of calling (n = 150), 93% contained mature eggs. Heavier females were significantly more likely to have mature eggs at adult emergence, to begin calling at a younger age and to spend more time calling on their first night of calling. The number of developed eggs in calling females was not significantly different in the presence or absence of host plants on the first night of calling. However, by the second night, females in the presence of plants contained significantly more eggs, indicating that the presence of plants accelerated egg maturation, both before and after the onset of calling.
Hemocyte surface changes in the migratory grasshopper, Melanoplus sanguinipes in response to wounding and infection with Beauveria bassiana
Authors: Miranpuri G. S. , Khachatourians G. G. 
Published: April 2011

AbstractSurface changes of hemocytes from the migratory grasshopper, Melanoplus sanguinipes (Fab.), following wounding and/or infection with Beauveria bassiana (Bals.) Vuillemin were assessed using fluorescein labelled wheat germ agglutinin (WGA) and concanavalin A (Con A). Binding was observed on outer wall of hemocytes when either Con A or WGA conjugates were tested. After infection there was an increase in the percentage of hemocytes which bound to WGA and which remained so for 24 h. However, after wounding this increase in binding subsided after only 1 h. Furthermore, it was found that the increase in WGA‐binding occurred within the first 15 min of wounding or infection. In addition, ConA binding in males only increased 3‐fold in fungus‐injected insects within 1 h of treatment and remained high for 24 h. These results indicated the presence of mannose (and/or glucose) residues (Con A specificity) and N‐acetyl‐D‐glucosamine residues (wheat germ agglutinin; WGA specificity) on outer wall surfaces of the hemocytes. The implications of these results in the immune response of M. sanguinipes to infection with B. bassiana are discussed.
Effects of the antifeedant polygodial on plant penetration by aphids, assessed by video and electrical recording
Authors: Powell G. , Hardie J. , Pickett J. A. 
Published: April 2011

AbstractAdult apterous Myzus persicae (Sulz.) discriminated within 2 min between mature Chinese cabbage (Brassica pekinensis L.) leaf halves treated with (±)‐polygodial solution and solvent alone, and walked off leaf areas treated with polygodial faster than off the solvent‐treated areas. However, when aphids were attached to a fine gold wire and stylet penetration of cabbage leaves was recorded electrically, polygodial treatment did not affect the number or duration of electrically‐recorded penetrations, time taken to initiate a first penetration, or total penetration time. As the tethering of aphids causes behavioural restrictions which may negate the response to polygodial, indications of stylet penetration by freely‐moving insects were sought. Simultaneous electrical recording and video monitoring showed that stylet penetration duration could be accurately inferred from antennal and body movements, enabling assessment of penetration times without attachment to the wire tether. When freely‐moving M. persicae were video recorded during 15 min access to cabbage seedlings, polygodial treatment again had no apparent effect on stylet penetration. However, when aphids were presented with a choice of polygodial‐ and solvent‐treated sides of floating mature cabbage leaf discs, video recordings revealed that the insects spent less time and made fewer penetrations on the polygodial‐treated side. In addition to this rapid repellent effect, prolonged exposure to polygodial also produced behavioural changes. After being held for 24 h on polygodial‐treated leaves or green paper prior to behavioural examination, aphids penetrated seedlings fewer times but for longer periods. The relevance of the results to virus transmission studies is discussed.
In vitro rearing of Bracon mellitor and Catolaccus grandis with artificial diets devoid of insect components
Authors: Guerra Antonio A. , Robacker Karen M. , Martinez Susana 
Published: April 2011

AbstractBracon mellitor Say (Hymenoptera: Braconidae), and Catolaccus grandis Burks (Hymenoptera: Pteromalidae), ectoparasitoids of the boll weevil, Anthonomus grandis Boheman, were reared in vitro for the first time on artificial diets devoid of insect components. The duration of the life cycles from egg to adult when these parasitoids were reared in vivo on boll weevil larvae, on semi‐artificial diets retained with cotton fabric pads, or on diets with low agar concentrations (0.7%) were ca. 15.5, 16.5, and 15.0 days, for B. mellitor and 16.0, 17.5, and 15.5 days, respectively, for C. grandis. Percent adult emergence obtained with the same treatments was 58, 25, and 65 percent, for B. mellitor and 50, 28, and 60 percent, respectively, for C. grandis. Adult morphological characteristics and mating appeared normal. Male to female sex ratios were ca. 45:55 for both species.
Evaluation of artificial diets and two species of natural prey as laboratory food for Chilocorus spp
Authors: Hattingh Vaughan , Samways Michael J. 
Published: April 2011

AbstractPromising diets were screened and the most successful modified with additives used in artificial diets for other entomophagous insects. Two suitable diets were obtained, one for adults and one for larvae of Chilocorus nigritus (Fabricius) (Coleoptera: Coccinellidae). They were still inferior to natural prey and not adequate as the sole food source for rearing consecutive generations. They are valuable as substitute food in the insectary during shortages of natural prey. Oleander scale Aspidiotus nerii Bouché and Asterolecanium miliaris (Boisduval) were evaluated as natural prey for C. nigritus and two other potential biocontrol agents in southern Africa, C. bipustulatus (Linnaeus) and C. infernalis Mulsant. A. nerii and A. miliaris were suitable for all life stages of C. nigritus and adults of C. bipustulatus and C. infernalis. A. miliaris was inadequate for larvae of C. bipustulatus and C. infernalis.