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101.
We studied movement behavior of the polyphagous herbivore Lygus rugulipennis Poppius (Heteroptera: Miridae) on wheat (Triticum aestivum) that had been cultivated in pots using three different levels of nitrogen fertilization. The probability of moving for fourth instar nymphs, and the time spent moving by mobile fourth and fifth instar nymphs increased with the nitrogen fertilization level of the pot. The nitrogen fertilization level of the pot did not appear to influence the probability of moving for fifth instar nymphs. The difference in movement behavior of nymphs on the pots of wheat fertilized with the lowest and the highest nitrogen levels seemed to be as great as the difference in movement behavior reported earlier on two different host plant species, viz., wheat and Tripleurospermum inodorum Schultz. The magnitude of the difference in movement behavior on the extreme nitrogen levels illustrates the importance of recognizing within species variation in plant quality when relating movement patterns of insect herbivores with host plant species. 相似文献
102.
Development and reproduction of a predatory stinkbug, Podisus nigrispinus in relation to two different prey types and environmental conditions 总被引:1,自引:0,他引:1
Abiotic factors, prey availability, prey type, and plant host actsimultaneously under field conditions. Their combined effects werepartially investigated for the predatory stinkbugPodisus nigrispinus(Dallas) (Heteroptera: Pentatomidae) preying on tomato leafminer (TLM)caterpillars Tuta absoluta (Meyrick)(Lepidoptera: Gelechiidae) (a preyfeeding on a plant host), and compared to yellow mealworm (YMW)Tenebrio molitor (Coleoptera: Tenebrionidae)pupae (a prey not feeding ona plant host). These experiments were carried out in the laboratory and inan open-sided greenhouse. In general, the environmental variationsbetween laboratory and open-sided greenhouse did not induce differencesin life history characteristics forP. nigrispinus feeding on the sameprey type. However, development and reproductionof P. nigrispinuswas greatly affected by prey type. Nymphal developmental times weresimilar between prey types under laboratory conditions; but were longer(and produced adults of lower body weight) when predators in theopen-sided greenhouse were fed on TLM compared with YMW. Mean mortalityduring the second instar was higher on both prey types in the open-sidedgreenhouse than in the laboratory. Adult emergencewas 38.5 and 50% inthe laboratory, and 32.5 and 48.6%in the open-sided greenhouse for bugsfed on TLM and YMW, respectively. Reproductive characteristics weresimilar for the different environmental conditions when the predator fed onthe same prey, but offspring production was greater for females fed on YMWcompared to females fed on TLM. These results suggest thatP. nigrispinus can adjust its performance accordingto the type of prey available, independently from environmentalvariations. It has the ability to survive on alternative prey,enabling it to maintain a presence in thetomato ecosystem until a primary pest species arrives. 相似文献
103.
Yolanda Bel Manuel Porcar Radomir Socha Vclav Nmec Juan Ferr 《Archives of insect biochemistry and physiology》1997,34(1):83-98
By using thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC), five different pteridines have been quantified in extracts from Pyrrhocoris apterus: neopterin, isoxanthopterin, isoxantholumazine (violapterin), 7-methylxanthopterin, and erythropterin. Biopterin was also detected using HPLC. Pteridines have been analyzed separately in bodies and eyes of the wild type regarding developmental stage and sex. The pteridine content in both bodies and eyes increased from nymphs to 2-day-old adults. After this period, the concentration of pteridines in the eyes of adults remained approximately constant, while in the bodies isoxantholumazine, 7-methylxanthopterin, and isoxanthopterin kept increasing until 20 days. Considering the total amount of pteridines per insect, no qualitative or quantitative differences between males and females have been observed except a lower concentration of erythropterin in female bodies. But when pteridines are analyzed per unit body weight, a lower amount of pteridines is always detected in females due to its bigger size. A new body-color mutant, the yolk body mutant, that goes through developmental colour changes, was also analyzed during development, showing a general deficient accumulation of all pteridines, especially of 7-methylxanthopterin and isoxantholumazine in adult bodies. The effect on pteridine content of three other recessive (white, yellow, mosaic) and two dominant (Pale and Apricot) body-color mutations, has also been studied. A specific pteridine pattern different from the wild type was obtained for each mutant. © 1997 Wiley-Liss, Inc. 相似文献
104.
Four African species of true water bugs (Nepomorpha: Hemiptera: Heteroptera) are studied by mass spectrometry and biological assays to gain information on the presence, structure and function of peptides from the adipokinetic hormone (AKH) family, which are produced in the corpora cardiaca (CC). The water scorpion Laccotrephes fabricii Stål (Nepidae) has the peptide code‐named Peram‐CAH‐I with the sequence pGlu‐Val‐Asn‐Phe‐Ser‐Pro‐Asn‐Trp amide, whereas Appasus grassei Poisson (Belostomatidae) produces Anaim‐AKH, which is a Ser7 analogue of Peram‐CAH‐I (pGlu‐Val‐Asn‐Phe‐Ser‐Pro‐Ser‐Trp amide). The giant water bug Hydrocyrius columbiae Spinola (Belostomatidae) has two adipokinetic hormone family members: Anaim‐AKH and Letin‐AKH, which again differ only at position 7 (Ser7 versus Tyr7). When the sequence data are compared with current molecular phylogenetic analyses of Nepomorpha, they are essentially in agreement with the newest ideas on phylogenetic relationships among the families. Functional investigation of these peptides reveals a mainly lipid‐based energy metabolism in these insects, as demonstrated by a hyperlipaemic response after injecting crude CC extract or the appropriate peptide into the respective species. The carbohydrate concentration in the haemolymph is not affected by such injections, and the carbohydrate level in most cases is lower than that of the circulating lipids. During physical exercise, such as swimming for 1 h, carbohydrates may contribute to some extent to the provision of energy; the substantial increase in the concentration of lipids in the haemolymph, however, is a strong indicator that the peptides are released from the CC and act primarily as true adipokinetic hormones during this period of intense muscular activity. 相似文献
105.
In the Coreoidea and some allied groups, male adults possess an abdominal gland opening through a midventral ostiole in the 7–8th abdominal intersegmental membrane. Using a GC-MS system, the following aromatic volatiles were identified in the abdominal gland secretion from males of the leaf footed bug, Leptoglossus phyllopus: guaiacol, benzyl alcohol, syringaldehyde, methyl p-hydroxybenzoate, acetosyringone, and vanillin. Males from which the glands were removed still mated and were competitive with control males for a limited number of females. The ventral abdominal gland secretion may act as a long-range attractant of females. The possibility that attraction of females by males in Heteroptera is an adaptation facilitating colonization of successional habitats is discussed. 相似文献
106.
Nicolai Vitt Meyling Annie Enkegaard & Henrik Brødsgaard 《Entomologia Experimentalis et Applicata》2003,108(1):59-70
Voracity and prey preference were evaluated for adult females of the predatory bugs Anthocoris nemorum (L.) and Anthocoris nemoralis (Fabricius) (Heteroptera: Anthocoridae) preying upon five species of aphids (Homoptera: Aphididae), of which Myzus persicae Sulzer, Aulacorthum solani (Kaltenbach), Macrosiphum euphorbiae (Thomas), and Aphis gossypii Glover are common pests in Danish glasshouse crops. Aphis fabae Scopoli was included to determine the influence of food quality on the preference of the predators, since A. fabae has proved to be of poor nutritional value to Anthocoris spp. The experiments were carried out over 24 h in climate cabinets at 20 °C, 60–70% r.h., L18:D6. The aphids were offered in equal amounts in combinations of two species in instars of comparable size. Myzus persicae served as a reference species in all combinations. Both predators accepted all five species of aphids as prey. The numbers of aphids killed per 24 h period varied between 3.7 and 18.0 for A. nemorum and between 3.6 and 12.7 for A. nemoralis. Field collected A. nemorum females, presumably in a state of reproductive diapause, killed in three of four prey combinations significantly more aphids than did ovipositing A. nemoralis females which originated from a commercial rearing. When A. nemorum females had terminated their reproductive diapause and commenced oviposition, voracity increased approximately threefold. When prey preferences were evaluated as a total number of killed prey, no difference in preference was found between the two Anthocoris species. Both predatory bugs preferred M. persicae to the other species, the most accepted alternative prey were A. gossypii, A. fabae, A. solani, and M. euphorbiae, in descending order. However, evaluating preference by number of aphids consumed, A. nemoralis showed a more pronounced preference for M. persicae, especially when combined with A. fabae. In nearly every case, A. nemoralis rejected A. fabae as a food item after killing the aphid. Thus, A. nemoralis exhibited a more specific food choice than A. nemorum. By killing and consuming different aphid species found in glasshouse crops – particularly M. persicae– both A. nemorum and A. nemoralis showed preliminary qualities as agents for the biological control of aphids. 相似文献
107.
A Furtado 《Journal of insect physiology》1979,25(7):561-570
Total or partial ablation experiments were performed on the pars interecerebralis (P.I.), thoracic glands and corpus allatum of Panstrongylus megistus at two critical times during the initial development of the ovary: the periods before the mitotic crisis and before meiosis.Ablation of the P.I. clearly shows that ovarian mitoses and meiosis in the female P. megistus are two distinct phenomena, both dependent on the brain. Induction of mitosis is regulated by the A cells of the P.I. Once the mitotic crisis is over, these cells are no longer necessary for further ovarian development or, in particular, for the initiation of meiosis. The latter is dependent on the A cells of the P.I.The thoracic gland is not required for ovarian mitosis, but is indispensable for meiosis to occur. The corpus allatum has no influence on the differentiation of the ovariole but seems to be required for correct ovarian function during the cytoplasmic growth period of the oöcytes. 相似文献
108.
To investigate the function of maternal care and determinantsof reproductive success in the subsocial bug Elasmucha putoni
(Heteroptera: Acanthosomatidae), I used two different approaches,the measurement of phenotypic selection and female-removalexperiments under conditions differing in biotic-environmentalpressure. For two field populations, unattended eggs and youngernymphs consistently suffered severe predation pressure andattendance by parent females greatly enhanced their survival.In contrast, under enemy-excluded conditions, offspring performance
was not reduced in broods without parent females, indicatingthat maternal care functions as a physical defense againstpredators. However, the determinant of female reproductivesuccess in E. putoni in the field was not the care behavioralone. Selection gradient analysis showed that early seasonoviposition and larger clutch size, as well as a longer durationof care by a female, was favored during the breeding episode.This study is the first to evaluate phenotypic selection onparental care and other reproductive traits in arthropods. 相似文献
109.
M. C. Coscaron M. C. Melo J. Coddington J. Corronca 《Biodiversity and Conservation》2009,18(6):1491-1507
The species richness and relative abundance of faunas in defined areas are the raw materials in biodiversity science. The
research methodology to acquire these data is inventory, and inventory quality depends on a number of parameters, for example
collecting methods, season, and collector experience. To assess the ability of rapid inventory techniques to estimate local
richness seven collectors sampled the fauna of true bugs in the Iberá watershed (Corrientes, Argentina) with seven methods
during early spring, summer, and late summer (December, May, September) of 1 year. Twenty-three families, 225 spp. and 4,678
adults were found. We also applied various statistical techniques to correct the observed data for undersampling bias, which
suggested the lower bound of annual heteropteran species richness at Pellegrini was about 250–300 species. Among heteropteran
families, the particular inventory methodology was especially efficient in sampling Miridae.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
110.
Two new glucosides, 3-β-d-glucopyranosyloxy-4-methyl-2(5H)-furanone and 4-β-d-glucopyranosyloxy-3-hydroxymethyl-butyronitril-2-en, were isolated from the hemolymph of adult Leptocoris isolata (Heteroptera). Besides these two compounds, the cyanogenic glucoside cardiospermin was found in whole adult bug extracts. The larvae contain the last two named compounds and a mixture of cyanolipids. Only the latter was found in the fruit of Allophylus cobbe, the host-plant of the insect. The possible relationship between the insect glucosides and the host-plant cyanolipids as well as their biological role is discussed. 相似文献