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51.
Giuseppina Logozzo Rosa Donnoli Leonardo Macaluso Roberto Papa Helmut Knüpffer Pierluigi Spagnoletti Zeuli 《Genetic Resources and Crop Evolution》2007,54(8):1763-1779
Common bean (Phaseolus vulgaris L.) was introduced in Europe from both Mesoamerican and Andean centres of origin. In this study, a collection including 544
accessions from all European regions showed that the Andean phaseolin types ‘T’ (45.6%) and ‘C’ (30.7%) prevailed over the
Mesoamerican ones ‘S’ (23.7%), and accessions with cuboid seed shape (34.9%), maroon coat darker colour seed (44.3%), uniform
seed colour (69.6%) were the most frequent. European accessions with phaseolin ‘S’ showed a significantly larger average seed
size compared to those from America in the same phaseolin class while those presenting ‘T’ and ‘C’ phaseolin did not. This
suggests that, during crop expansion in Europe, sampling or selection favoured the large-seeded races within the Mesoamerican
‘S’ gene pool or, possibly, introgression from Andean germplasm did occur. A core collection was developed using sampling
approaches based on the information available in the genebank databases and on phaseolin patterns. Four sampling strategies
were used: simple random sampling, and three random-stratified samplings, by logarithm of frequency of accessions by country,
by European region, and by phaseolin pattern, respectively. Two sampling strategies resulted in core collections significantly
different for phaseolin electrophoretic patterns from the whole collection. Stratification by phaseolin patterns increased
the frequency of ‘S’ types (‘C’ type = 33%, ‘T’ type = 5.7% and ‘S’ type = 31.3%). The core collections were validated using
seven seed characters, and no significant difference was observed in all strategies. This first developed European bean core
collection will help to assess the contribution of the two American gene pools to the European germplasm and their relative
importance for breeding purposes. 相似文献
52.
Antonietta Fioretto Carmelina Di Nardo Stefania Papa Amodio Fuggi 《Soil biology & biochemistry》2005,37(6):1083-1091
Cellulose and lignin degradation dynamics was monitored during the leaf litter decomposition of three typical species of the Mediterranean area, Cistus incanus L., Myrtus communis L. and Quercus ilex L., using the litter bag method. Total N and its distribution among lignin, cellulose and acid-detergent-soluble fractions were measured and related to the overall decay process. The litter organic substance of Cistus and Myrtus decomposed more rapidly than that of Quercus. The decay constants were 0.47 year−1, 0.75 year−1 and 0.30 year−1 for Cistus, Myrtus and Quercus, respectively. Lignin and cellulose contents were different as were their relative amounts (34 and 18%, 15 and 37%, 37 and 39% of the overall litter organic matter before exposure, for Cistus, Myrtus and Quercus, respectively). Lignin began to decrease after 6 and 8 months of exposure in Cistus and Myrtus, respectively, while it did not change significantly during the entire study period in Quercus. The holocellulose, in contrast, began to decompose in Cistus after 1 year, while in Quercus and Myrtus immediately. Nitrogen was strongly immobilized in all the litters in the early period of decay. Its release began after the first year in Cistus and Myrtus and after 2 years of decomposition in Quercus. These litters still contained about 60, 20 and 90% of the initial nitrogen at the end of the experiment (3 years). Prior to litter exposure nitrogen associated with the lignin fraction was 65, 54 and 37% in Cistus, Myrtus and Quercus, while that associated with the cellulose fraction was 30, 24 and 28%. Although most of the nitrogen was not lost from litters, its distribution among the litter components changed significantly during decomposition. In Cistus and Myrtus the nitrogen associated with lignin began to decrease just 4 months after exposure. In Quercus this process was slowed and after 3 years of decomposition 8% of the nitrogen remained associated with lignin or lignin-like substances. The nitrogen associated with cellulose or cellulose-like substances, in contrast, began to decrease from the beginning of cellulose decomposition in all three species. At the end of the study period most of the nitrogen was not associated to the lignocellulose fraction but to the acid-detergent-soluble substance (87, 88 and 84% of the remaining litter nitrogen). 相似文献
53.
Laura O. Teodoro Laiza S. Camargo Verônica F. C. Scheeren Camila P. Freitas-Dell'Aqua Frederico O. Papa Cristiane S. Honsho Fabiana F. Souza 《Reproduction in domestic animals》2021,56(11):1464-1469
This study aimed to describe successful cryopreservation of sperm from maned wolves (Chrysocyon brachyurus). Three ejaculates from 2 maned wolves were collected by digital manipulation of the penis and evaluated subjectively, centrifuged and frozen in BotuCrio® (Botupharma, Botucatu, Brazil) or Tris–yolk egg extender. Spermatozoa were thawed at 37ºC/30s or 70ºC/4s and evaluated for kinetics, morphology, plasma and acrosome membrane integrity, mitochondrial potential, hydrogen peroxide, superoxide anion and lipid peroxidation. From 5 thawed samples, two had sperm total motility >55% (56.0% and 64.0%) and progressive motility ~35% (35% and 40%), both frozen with Tris–yolk egg. Plasma and acrosome membrane integrity decreased and percentage of sperm defects increased post-thawing. We concluded that is possible to freeze spermatozoa from maned wolves using semen collection and processing methods applied for domestic dogs. 相似文献
54.
Unfolded proteins in the endoplasmic reticulum cause trans-autophosphorylation of the bifunctional transmembrane kinase Ire1, which induces its endoribonuclease activity. The endoribonuclease initiates nonconventional splicing of HAC1 messenger RNA to trigger the unfolded-protein response (UPR). We explored the role of Ire1's kinase domain by sensitizing it through site-directed mutagenesis to the ATP-competitive inhibitor 1NM-PP1. Paradoxically, rather than being inhibited by 1NM-PP1, drug-sensitized Ire1 mutants required 1NM-PP1 as a cofactor for activation. In the presence of 1NM-PP1, drug-sensitized Ire1 bypassed mutations that inactivate its kinase activity and induced a full UPR. Thus, rather than through phosphorylation per se, a conformational change in the kinase domain triggered by occupancy of the active site with a ligand leads to activation of all known downstream functions. 相似文献
55.
Gabriel A. Monteiro Camila P. Freitas-Dell'AquaPriscilla N. Guasti MSc José Antonio Dell'Aqua Jr.Marco A. Alvarenga PhD Fernanda C. LandimFrederico O. Papa PhD 《Journal of Equine Veterinary Science》2013
The development of a reliable technique to freeze epididymal semen would provide a unique opportunity to preserve valuable genetic material from unexpectedly lost stallions. The aim of this study was to compare the apoptotic indices of sperm obtained from ejaculate, sperm recently recovered from the epididymides (EP), and sperm recovered from epididymides stored at 5°C for 24 hours (EP-stored). For the first category, two ejaculates from seven stallions were collected and then submitted to cryopreservation using an egg yolk-based extender. One week after the last semen collection, the stallions were submitted to bilateral orchiectomy, and sperm from one of the cauda epididymis was harvested immediately after castration (EP). The remaining testicle was stored in a passive refrigeration container at 5°C for 24 hours before the cauda epididymal sperm was harvested (EP-stored). Sperm harvesting from the epididymis for EP and EP-stored was performed by retrograde flushing of the caudal portion of the epididymis using a skim milk-based extender. The recovered sperm was then cryopreserved using the egg yolk-based extender. Sperm motility parameters were studied by computer-assisted semen analysis, and apoptosis was estimated by measuring caspase activity and membrane phospholipid translocation using epifluorescence microscopy. The samples were evaluated immediately (0 hour) and 8 hours after thawing. At 0 hour, no differences in sperm parameters were observed among the groups, but after 8 hours, significant statistical differences were observed in sperm motility parameters and plasma membrane integrity among the treatment groups. In addition, viable cells with no apoptotic signs were more prevalent in EP and EP-stored, suggesting that epididymal sperm is less sensitive to the cold shock caused by sperm cryopreservation. 相似文献
56.
Papa Saliou Sarr Shigeru Araki Didier Aime Begoude Martin Yemefack Gabriel Ambroise Manga Takeo Yamakawa 《Soil Science and Plant Nutrition》2016,62(1):13-19
Pueraria is an herbaceous, perennial legume crop originating in Asia. Pueraria phaseoloides (Roxb.) Benth. (tropical kudzu) is frequently introduced into production systems and is used as green manure, a cover crop and a forage plant, making it important economically. We used P. phaseoloides as a trap crop to study and characterize soil rhizobia in Eastern Cameroon. Bacteria were isolated from fresh nodules collected from field-grown P. phaseoloides roots. The 16S-23S rRNA internal transcribed spacer (ITS) sequences from 30 bacterial isolates were amplified by polymerase chain reaction (PCR) and the reaction products were sequenced. Phylogenetic analysis revealed that all isolates were ascribed to the genus Bradyrhizobium and were grouped into three clusters of Bradyrhizobium sp. strains, one cluster of B. yuanmingense strains, and one cluster of B. elkanii strains. Acetylene reduction assay (ARA) results indicated that the B. yuanmingense strains had significantly higher nitrogen fixation potential and that they could be used as inoculants to enhance nitrogen fixation in Pueraria grown in Eastern Cameroon. 相似文献
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