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J. K. KIRKWOOD P. J. DUIGNAN N. F. KEMBER P. M. BENNETT and D. J. PRICE 《Journal of Zoology》1989,217(3):403-416
Twisting and bending deformities of the long limb bones of growing birds are common. In domestic poultry they are associated with rapid growth. In order to examine the variation in bone growth rates amongst the Class Aves as a step towards learning about the aetiology of growth deformities, we collected data on this and several other variables from a large sample of species. Adult tarsometatarsal length (ATL) was proportional to adult weight (W)0.36 . The exponent did not differ significantly from 1/3. Mean legginess (L), defined as ATL/W1/3 (i.e. ATL.W-1/3 ), was 80 mm.kg-1/3 but varied according to the habitat occupied; terrestrial and arboreal birds had relatively longer legs than aquatic and aerial ones. ATL growth rate (GR) averaged 20 mm.d-1 and was not correlated with W. It was highly influenced by pattern of development, being on average about three times greater in altricial compared with precocial birds of the same adult weight. Amongst birds of the same developmental pattern, GR was linearly related to L. Tarsometatarsal growth rate varied from 0.35 to 60 mm.d-1 in the Class Aves and there was no evidence of intrinsic limits to GR from our results. How rapidly such bone growth rates are achieved remains to be determined. 相似文献
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Four Chinese Brassica napus lines, generated through a breeding programme to identify Sclerotinia sclerotiorum tolerant and susceptible lines, and three European varieties were analysed for changes in glucosinolates (qualitative and quantitative), and general host reactions, after localised inoculation with a UK S. sclerotiorum isolate. Plants at the fifth leaf stage were either singly inoculated (third leaf) or were inoculated once (third leaf) and then challenged a second time (seventh leaf) 7 days after the first inoculation. The results showed very distinct reactions in the different lines and cultivars to the fungus, both locally and systemically. Of the European lines B. napus cv. Bienvenu showed good resistance (small lesions and less host damage) both 3 and 7 days post-inoculation. Capricorn was the most susceptible followed by Cobra; the third leaves of these cultivars were showing strong chlorotic and necrotic reactions by day 3 and lesions were well developed. By day 7 the third leaves of Capricorn were completely rotten whilst Cobra still had a little healthy tissue. Inoculation of the four Chinese lines showed that two had moderate resistance (014 and 020 — slightly less resistant than Bienvenu) and two were very susceptible (016 and 024 — similar reactions to Capricorn and Cobra), based on lesion size and host tissue damage. Glucosinolate induction in line 014 was good both locally and systemically, with clear local and systemic induction of indolylglucosinolates and 2-phenylethylglucosinolate both 3 and 7 days post-inoculation. Line 020 did not show no particular increases in glucosinolates after inoculation either locally or systemically. In line 016 there was a small local increase and a large systemic reduction in total glucosinolates. Inoculation of line 024 caused no major local changes in glucosinolates and again a big reduction in glucosinolates systemically. The dual inoculation system, with lines 014 and 016, produced comparable results, with line 014 showing good local and systemic induction of glucosinolates (after the first inoculation) and a further local and systemic induction after the second inoculation. This induction in pre-inoculated line 014 plants was associated with a reduction in lesion size of the second inoculum. Line 016 responded poorly both locally and systemically, and there were no real decrease in the lesion size of the second inoculum. It appears that in line 014 glucosinolate induction may be an important part of resistance, whereas in line 020 there are clearly other non-glucosinolate factors involved. The poor local and systemic induction of glucosinolates in lines 016 and 024, and subsequent susceptibility, implies that glucosinolate induction may be an important marker of resistance to S. sclerotiorum in oilseed rape. 相似文献
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Plant and insect genetic variation mediate the impact of arbuscular mycorrhizal fungi on a natural plant–herbivore interaction
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PIL U. RASMUSSEN TARIQUE AMIN ALISON E. BENNETT KRISTINA KARLSSON GREEN SARI TIMONEN SASKYA VAN NOUHUYS AYCO J. M. TACK 《Ecological Entomology》2017,42(6):793-802
1. While both arbuscular mycorrhizal (AM) fungi and plant and insect genotype are well known to influence plant and herbivore growth and performance, information is lacking on how these factors jointly influence the relationship between plants and their natural herbivores. 2. The aim of the present study was to investigate how a natural community of arbuscular mycorrhizal fungi affects the growth of the perennial herb Plantago lanceolata L. (Plantaginaceae), as well as its interaction with the Glanville fritillary butterfly [Melitaea cinxia L. (Nymphalidae)]. For this, a multifactorial experiment was conducted using plant lines originating from multiple plant populations in the Åland Islands, Finland, grown either with or without mycorrhizal fungi. For a subset of plant lines, the impact of mycorrhizal inoculation, plant line, and larval family on the performance of M. cinxia larvae were tested. 3. Arbuscular mycorrhizal inoculation did not have a consistently positive or negative impact on plant growth or herbivore performance. Instead, plant genetic variation mediated the impact of arbuscular mycorrhizal fungi on plant growth, and both plant genetic variation and herbivore genetic variation mediated the response of the herbivore. For both the plant and insect, the impact of the arbuscular mycorrhizal community ranged from mutualistic to antagonistic. Overall, the present findings illustrate that genetic variation in response to mycorrhizal fungi may play a key role in the ecology and evolution of plant–insect interactions. 相似文献
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BENNETT LC 《California medicine》1952,76(4):289-293
For their value as factors in the evaluation of pancreatoduodenectomy for carcinoma of the ampulla of Vater, the late results in three cases in which the Whipple operation was performed for this lesion are presented. At the time of the report, the time that had elapsed since operation was 12 years in one case, 11 in another and 10 in the third. After this article was written, one patient died of carcinoma of the body of the pancreas, but whether the lesion was a recurrence, a metastatic growth, or a second primary lesion could not be determined. There was no evidence of recurrence or metastasis in two of the patients. This report is based upon observation in recent surgical care of two of the patients and upon direct information of the other patient. 相似文献