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991.
N. N. Kakareka Z. N. Kozlovskaya Yu. G. Volkov T. I. Pleshakova 《Russian Agricultural Sciences》2008,34(4):227-229
Infection of pepper caused by an isometric virus with a 30 ± 3 nm virion diameter is revealed. The thermal inactivation point of virus in jimsonweed sap is 75–80°C, longevity in vitro 3 days at 25°C, and dilution end-point of virus 10?3–10?4. The capsid of the virus contains two types of protein with molecular mass 55 and 12.6 kDa. A distant antigenic relatedness to the tobacco ringspot virus of the genus Nepovirus is shown. 相似文献
992.
Michel E Baglin A Auvergne M Catala C Samadi R Baudin F Appourchaux T Barban C Weiss WW Berthomieu G Boumier P Dupret MA Garcia RA Fridlund M Garrido R Goupil MJ Kjeldsen H Lebreton Y Mosser B Grotsch-Noels A Janot-Pacheco E Provost J Roxburgh IW Thoul A Toutain T Tiphène D Turck-Chieze S Vauclair SD Vauclair GP Aerts C Alecian G Ballot J Charpinet S Hubert AM Lignières F Mathias P Monteiro MJ Neiner C Poretti E de Medeiros JR Ribas I Rieutord ML Cortés TR Zwintz K 《Science (New York, N.Y.)》2008,322(5901):558-560
Oscillations of the Sun have been used to understand its interior structure. The extension of similar studies to more distant stars has raised many difficulties despite the strong efforts of the international community over the past decades. The CoRoT (Convection Rotation and Planetary Transits) satellite, launched in December 2006, has now measured oscillations and the stellar granulation signature in three main sequence stars that are noticeably hotter than the sun. The oscillation amplitudes are about 1.5 times as large as those in the Sun; the stellar granulation is up to three times as high. The stellar amplitudes are about 25% below the theoretic values, providing a measurement of the nonadiabaticity of the process ruling the oscillations in the outer layers of the stars. 相似文献
993.
用RT-PCR扩增含有XhoI/EcoRI酶切位点的Sirt1片段,克隆、测序后,构建真核荧光表达载体pEGFP-N1-Sirt1、脂质体介导转染293细胞,最后利用SDS-PAGE检测蛋白表达情况.结果表明,经脂质体介导重组体pEGFP-N1-Sirt1可成功转染293细胞;转染48h后.荧光显微镜下可见绿色荧光蛋白表达;SDS-PAGE证明表达的融合蛋白相对分子质量约为41kD.该结果为进一步研究Sirt1在哺乳动物细胞中的作用奠定了基础. 相似文献
994.
Wild types of Lupinus angustifolius require vernalization to promote flowering. Modern domesticated cultivars carry the early-flowering gene Ku which removes this requirement. A microsatellite-anchored fragment length polymorphism marker was identified as co-segregating with the Ku gene in a recombinant inbred line (RIL) population derived from a domesticated × wild-type cross. DNA sequencing showed that the marker contained a 7 bp insertion/deletion polymorphism, as well as a single nucleotide polymorphism. A pair of sequence-specific primers was designed and successfully converted the size polymorphism into a simple polymerase chain reaction based co-dominant marker. This marker is closely linked to the Ku gene, as it co-segregates with the Ku phenotyping in a population consisting of 106 RILs. 相似文献
995.
Linkage and quantitative trait locus mapping of foliage late blight resistance in the wild species Solanum vernei 总被引:1,自引:0,他引:1
The global cultivation of potato (Solanum tuberosum) is threatened by epidemics caused by new variants of the late blight pathogen, Phytophthora infestans. New sources of durable late blight resistance are urgently needed and these may be found in wild Solanum species. The diploid wild species, S. vernei, has not previously been subjected to mapping of quantitative trait loci (QTLs) for late blight resistance. Two populations designated HGIHJS and HGG, originating from a cross between a clone of S. vernei and two different S. tuberosum clones were evaluated in field trials for late blight infestation. The relative area under the disease progress curve (RAUDPC) was estimated and used for QTL mapping. A linkage map of S. vernei, comprising 11 linkage groups, nine of which could be assigned to chromosomes, was constructed. Results indicated that the resistance in S. vernei was quantitatively inherited. Significant QTLs for late blight resistance were identified on chromosomes VIII (HGG), VI and IX (HGIHJS). In addition, potential QTLs were detected on chromosomes VII (HGIHJS) and IX (HGG). A putative and a significant QTL for tuber yield were found on chromosomes VI and VII in HGG, but no linkage between yield and resistance was indicated. The QTL for late blight resistance, which mapped to chromosome IX, could be useful for late blight resistance breeding as it was located close to the microsatellite marker STM1051 in both populations. 相似文献
996.
Pronob J. Paul Srinivasan Samineni Sobhan B. Sajja Abhishek Rathore Roma R. Das Sushil K. Chaturvedi G. R. Lavanya Rajeev K. Varshney Pooran M. Gaur 《Euphytica》2018,214(2):27
Chickpea is the most important pulse crop globally after dry beans. Climate change and increased cropping intensity are forcing chickpea cultivation to relatively higher temperature environments. To assess the genetic variability and identify heat responsive traits, a set of 296 F8–9 recombinant inbred lines (RILs) of the cross ICC 4567 (heat sensitive) × ICC 15614 (heat tolerant) was evaluated under field conditions at ICRISAT, Patancheru, India. The experiment was conducted in an alpha lattice design with three replications during the summer seasons of 2013 and 2014 (heat stress environments, average temperature 35 °C and above), and post-rainy season of 2013 (non-stress environment, max. temperature below 30 °C). A two-fold variation for number of filled pods (FPod), total number of seeds (TS), harvest index (HI), percent pod setting (%PodSet) and grain yield (GY) was observed in the RILs under stress environments compared to non-stress environment. A yield penalty ranging from 22.26% (summer 2013) to 33.30% (summer 2014) was recorded in stress environments. Seed mass measured as 100-seed weight (HSW) was the least affected (6 and 7% reduction) trait, while %PodSet was the most affected (45.86 and 44.31% reduction) trait by high temperatures. Mixed model analysis of variance revealed a high genotypic coefficient of variation (GCV) (23.29–30.22%), phenotypic coefficient of variation (PCV) (25.69–32.44%) along with high heritability (80.89–86.89%) for FPod, TS, %PodSet and GY across the heat stress environments. Correlation studies (r = 0.61–0.97) and principal component analysis (PCA) revealed a strong positive association among the traits GY, FPod, VS and %PodSet under stress environments. Path analysis results showed that TS was the major direct and FPod was the major indirect contributors to GY under heat stress environments. Therefore, the traits that are good indicators of high grain yield under heat stress can be used in indirect selection for developing heat tolerant chickpea cultivars. Moreover, the presence of large genetic variation for heat tolerance in the population may provide an opportunity to use the RILs in future-heat tolerance breeding programme in chickpea. 相似文献
997.
James G. Nuttall Eileen M. Perry Audrey J. Delahunty Garry J. O'Leary Kirsten M. Barlow Ashley J. Wallace 《Journal of Agronomy and Crop Science》2019,205(2):220-234
Frost can significantly reduce production of field crops grown in Mediterranean‐type environments, where significant economic losses for Australian wheat occur annually. If non‐destructive sensors could make rapid, spatial assessment of frost damage, this could limit economic losses through timely management decisions. This paper reports on a methodology for imposing frost treatments to wheat under field conditions and the utility of canopy reflectance data for detecting early crop damage. Purpose‐built chambers using stepped additions of dry ice allowed for a range of frost scenarios to be tested when applied at wheat heading and anthesis. For frost treatments applied at anthesis, grain number and yield were reduced by 8.8% and 7.2%, respectively, for every degree Celsius below zero (down to ?4°C). This effect was additive over two consecutive nights. For cold load equivalent, there was a 2.2% and 1.9% reduction in grain number and yield, respectively, per °C hr (below 0°C). For wheat, spectral indices PRI and NDVI (reflectance) and FRF_G and SFR_G (fluorescence) showed significant relationships, with cold load applied for heading treatments. Next steps include targeting frost intensities equivalent to cold loads between 20 and 80°C hr and testing the utility of these proposed indices in a commercial paddock setting. 相似文献
998.
Sergio Hernández-Verdugo Ramón G. Guevara-González Rafael F. Rivera-Bustamante Ken Oyama 《Euphytica》2001,122(1):31-36
Plants collected in thirteen wild populations of Capsicum annuum from Northwest Mexico were tested for resistance to the pepper huasteco begomovirus (formerly subgroup III) (PHV) that is
transmitted by the white fly Bemisia tabaci Genadius. Plants were inoculated using both grafting and biolistic methods. Presence of viral DNA was detected by dot blot
hybridization and densitometry. Populations varied in their resistance to PHV. Plants of only two of the populations either
did not develop disease symptoms or showed very light symptoms after inoculation. In some cases, symptoms appeared several
days after inoculation. In plants of these populations viral DNA was detected by dot-blot hybridization assays but they appear
to be a good source of resistance (symptomless) for use in breeding programmes.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
999.
RAPD variation within and among populations of globe artichoke cultivar 'Spinoso sardo' 总被引:4,自引:0,他引:4
Globe artichoke is a vegetable native to the Mediterranean basin. Its commercial production is mainly based on perennial cultivation of vegetatively propagated clones, which are highly heterozygous and segregate widely when progeny‐tested. The aim of this study was to measure genetic variation using random amplified polymorphic DNA (RAPD) in five populations of ‘Spinoso sardo’, the most widely grown and economically important cultivar in Sardinia (Italy). Analysis of molecular variance (amova ) gave highly significant differences between populations (28.1% of the total genetic diversity); substantial within‐population variation was detected (71.8% of total genetic diversity). The RAPD results show the need to apply clonal selection to narrow the broad genetic variability within the cultivar and to address important questions on the most suitable strategies for germplasm preservation. 相似文献
1000.
B.I.G. Haussmann D.E. Hess B.V.S. Reddy S.Z. Mukuru M. Kayentao H.G. Welz H.H. Geiger 《Euphytica》2001,122(2):297-308
The parasitic weed Striga hermonthica (Del.) Benth. seriously limits sorghum [Sorghum bicolor (L.) Moench] production in Sub-Saharan Africa. As an outbreeder, S. hermonthica is highly variable with an extraordinary capacity to adapt to different hosts and environments, thereby complicating resistance
breeding. To study genotype x environment (G x E) interaction for striga resistance and grain yield, nine sorghum lines, 36
F2 populations and five local checks were grown under striga infestation at two locations in both Mali and Kenya. Mean squares
due to genotypes and G x E interaction were highly significant for both sorghum grain yield and area under striga severity
progress curve(ASVPC, a measure of striga emergence and vigor throughout the season). For grain yield, the entry x location-within-country
interaction explained most of the total G x E while for ASVPC, entry x country and entry x location-within-country interactions
were equally important. Pattern analysis (classification and ordination techniques) was applied to the environment-standardized
matrix of entry x environment means. The classification clearly distinguished Malian from Kenyan locations for ASVPC, but
not for grain yield. Performance plots for different entry groups showed differing patterns of adaptation. The ordination
biplot underlined the importance of entry x country interaction for ASVPC. The F2 derived from the cross of the striga-resistant line Framida with the striga-tolerant cultivar Seredo was the superior entry
for both grain yield and ASVPC, underlining the importance of combining resistance with tolerance in striga resistance breeding.
The observed entry x country interaction for ASVPC may be due to the entries' different reactions to climatic conditions and
putative differences in striga virulence in Mali and Kenya.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献