..., phloem sap is a nutritionally unbalanced diet for phloem-feeding insects. Therefore, aphids and other phloem feeders typically rely on microbial symbionts for the synthesis of essential amino acids. To investigate the metabolism of the four main transport amino acids by the pea aphid (Acyrthosiphon pisum...

...A. E. Douglas; D. R. G. Price; L. B. Minto; E. Jones; K. V. Pescod; C. L. M. J. François; J. Pritchard; N. Boonham SUMMARY Plant phloem sap is an extreme diet for animals, partly because of its high and variable sugar content. The physiological and feeding traits of the pea aphid Acyrthosiphon...

... aphid Sitobion avenae Fabricus was low-temperature acclimated by rearing for three generations at 10°C, the discriminating temperatures (temperature that results in approximately 20% survival after direct transfer from the rearing temperature to a sub-zero temperature for a period of 3 h), of first...

...A. J. Karley; A. E. Douglas; W. E. Parker SUMMARY To define plant `nutritional quality' for aphids, the causal basis of the variation in aphid performance between host plants of different developmental ages was explored using the aphids Myzus persicae and Macrosiphum euphorbiae on potato plants...

...T. L. Wilkinson; D. Adams; L. B. Minto; A. E. Douglas SUMMARY The black-bean aphid Aphis fabae bears populations of coccoid symbiotic bacteria Buchnera spp. at 2.0–3.2×10 7 cellsmg −1 aphidmass and rod-shaped secondary symbionts of uncertain taxonomic affiliation at 0.1–0.6×10 7 cellsmg −1...

...A. E. Douglas; L. B. Minto; T. L. Wilkinson ABSTRACT The symbiotic bacteria Buchnera sp. provide aphids with essential amino acids, nutrients in short supply in the aphid diet of plant phloem sap. The contribution of Buchnera -derived amino acids to net protein growth of the aphid Aphis fabae...

...T. L. Wilkinson; D. A. Ashford; J. Pritchard; A. E. Douglas ABSTRACT Pea aphids, Acyrthosiphon pisum , containing their symbiotic bacteria (untreated aphids) and experimentally deprived of their bacteria by treatment with the antibiotic rifampicin (antibiotic-treated aphids) were reared...

...J. D. Rhodes; P. C. Croghan; A. F. G. Dixon ABSTRACT Ingestion, excretion and respiration in aphids were studied using artificial diets labelled with radioactive sucrose or amino acids. The rate of ingestion of a 25 % w/v sucrose diet was 12.4 nl mg –1 h –1 and the honeydew excretion rate was 5.3...

...A. F. G. Dixon; P. C. Croghan; R. P. Gowing ABSTRACT The adhesive force acting between the adhesive organs and substratum for a number of aphid species has been studied. In the case of Aphis fabae , the force per foot is about 10 μ N. This is much the same on both glass (amphiphilic) and silanized...

... amputation. Pulling forces were applied by progressively loading the aphid with weights. The pulvilli perform best on relatively smooth surfaces. Aphids are dislodged from the underside of polished glass by a mass of approx. 9-14 mg (a pulling force of 8·8-13·7xl0 -5 N). The claws cannot engage a completely...