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1.
Bertin N.; Guichard S.; Leonardi C.; Longuenesse J. J.; Langlois D.; Navez B. 《Annals of botany》2000,85(6):741-750
Changes in yield and quality of fresh tomatoes in response toair vapour pressure deficit (VPD) and plant fruit load werestudied under Mediterranean summer conditions. Plants thinnedto three or six fruits per truss were grown in two compartments,one at a VPD below 1.5 kPa, the other without VPD control. Theseasonal trend in fruit yield and quality was assessed fromApril to September by weekly measurement of number, fresh weightand dry matter content of harvested fruits, together with theoccurrence of blossom-end-rot (BER) and cracking. On two occasions,in July and September, sugar and acid content was measured atthree ripening stages. The seasonal decrease in fresh yieldwas attenuated at low VPD, because of higher individual fruitfresh weight, especially at low fruit load. Low VPD decreasedoccurrence of BER but like low fruit load, it increased fruitcracking. Fruit dry matter content was lower at low VPD, butwas unaffected by fruit load. Sugar content and the ratio ofsugars:acids was increased at high VPD and low fruit load, withinteractive effects depending on season and ripening stage.The influence of VPD on acid content differed with fruit loadand also changed during ripening and between seasons. Resultsshowed that water was the main limiting factor for growth offruits picked in July; at this time, reducing fruit load topromote mean fruit size had negative effects on BER and cracking.Reducing VPD reduced BER but had a negative effect on crackingand diluted both the dry matter and sugar content. For fruitsharvested later in summer, these negative effects were attenuatedbecause fruit growth was also carbon limited. Copyright 2000Annals of Botany Company Lycopersicon esculentum Mill., tomato, water and carbon stress, yield, quality, dry matter, sugar, acid, BER, volatile composition 相似文献
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Helen J. Michaels B. Benner A. P. Hartgerink T. D. Lee S. Rice Mary F. Willson Robert I. Bertin 《Evolutionary ecology》1988,2(2):157-166
Summary We examined seed-mass variation in 39 species (46 populations) of plants in eastern-central Illinois, USA. The coefficient of variation of seed mass commonly exceeded 20%. Significant variation in mean seed mass occurred among conspecific plants in most species sampled (by hierarchical ANOVA), averaging 38% of total variance. For most species, within-plant variation was the larger component of total variance, averaging 62% of total variance. Variation in seed mass among fruits within crops was significant in most species tested.We conclude that variation in seed mass among and within plants is widespread and common. There was little evidence of trade-offs between number of seeds and mean or variance of seed mass, and little correlational evidence of local competition for maternal resources. No consistent ecological (dispersal mode and growth form) correlates of variance of seed mass were evident. 相似文献
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S Caillat-Zucman E Bertin J Timsit C Boitard R Assan J F Bach 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1992,315(13):535-539
Genetic control of insulin dependent diabetes mellitus (IDDM) is mainly dependent on HLA genes in the major histocompatibility complex (MHC). The participation of TAP1 and TAP2 genes, located in the MHC region and coding for antigenic peptide transporters, was investigated in 116 IDDM patients and 98 normal controls using oligotyping after DNA amplification. The TAP2-B allele had a dominant protective effect, additive to that of the DR2 haplotype but antagonist to the susceptibility associated with the DR3 and/or DR4 haplotypes. The TAP2-A allele, in the homozygous state, had a predisposing effect. TAP1 allelic distribution did not differ among IDDM patients and controls. These data argue in favour of the role of peptide transporter gene in diabetogenesis. 相似文献
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Yolande Bertin Jean-Pierre Girardeau Maurice Der Vartanian Christine Martin 《FEMS microbiology letters》1993,108(1):59-67
Abstract The putative chaperone-like protein ClpE, required for biogenesis of the Escherichia coli capsule-like antigen CS31A, was compared with ten known periplasmic chaperones from E. coli, Klebsiella pneumoniae, Bordetella pertussis, Haemophilus influenzae and Yersinia pestis . The amino acid sequence alignment was superimposed onto the three-dimensional structure of the PapD chaperone of uropathogenic E. coli , and amino acid residues involved in maintaining the structure integrity of the suggested binding site were found identical in most of the 11 chaperones. Construction of a phylogenetic tree to investigate the relationship within the chaperone family has revealed interesting degrees of relatedness between the different proteins. 相似文献
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R. Schoysman B. Lejeune E. Van Roosendaal L. Segal P. Vanderzwalmen M. Nijs B. Vandamme G. Bertin 《Andrologie》1996,6(4):432-439
The authors report their experience with the use of spermatids in TESE programs where mature spermatozoa could not be isolated from testicular biopsies. The details of the indications for spermatid insemination, the technicity of the procedure and the results are exposed. 相似文献
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The blacks of Panama: their genetic diversity as assessed by 15 inherited biochemical systems 总被引:1,自引:0,他引:1
R E Ferrell A Nunez T Bertin D R Labarthe W J Schull 《American journal of physical anthropology》1978,48(3):269-275
Panama's black citizens are culturally and historically divisible into two groups, the Spanish-speaking coloniales and the English-speaking anglos or afro-antillanos. Until recently these groups have been geographically as well as culturally isolated one from the other, although both are predominantly of West and Southwest African origin. Assessment of the genetic diversity within-villages and within language groups reveals as much, possibly somewhat more, diversity in 15 inherited biochemical markers within villages and language groups as that which obtains between villages and language groups. A number of rare variants at the 6-phosphogluconate dehydrogenase, lactate dehydrogenase, and esterase D loci were encountered and are described. 相似文献