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951.
952.
self-(in)compatibility almond genotypes: A review 总被引:1,自引:0,他引:1
To compile self-(in)compatibility almond genotypes, a review of 133 commercial cultivars of wide geographical origin was made. The information gathered from own and mainly published work will be useful for both grower's cultivar choice when planting and for breeder's cross design when planning. The almond S genotypes compiled were identified using five different methods: biological (pollination tests in the field and in the laboratory) and molecular (RNases, PCR and sequencing). In most cases, genotypes were assigned after combining more than one technique. Cultivars were classified into three categories: self-incompatible (99), self-compatible (16) and doubtful self-incompatible (18). The database is divided in 9 fields (name, origin, parentage, obtention year (crossing, selection or release), S genotype, technique used, reference, consensus genotype, and cross incompatibility group). A study of the 27 S alleles already identified and their geographical distribution within the cultivated almond is also presented. The study was divided into cultivars of known and unknown parentage and the distribution of S alleles frequencies was uneven among the 133 cultivars. S allele frequencies are related to geographical origin. Some alleles (S
1, S
5, S
7 and S
8) are more frequently observed than the others among cultivars of both known and unknown parentage. In the cultivated almond, the S
f allele is only found in the Puglia region, Italy. The S
f
frequency is three times higher in cultivars released from breeding programmes than in cultivars selected by growers. From the 351 resulting possible genotypes by combination of the 27 S alleles identified only 20 CIG (0-XIX) have been established, which represents a small fraction of the whole genetic diversity of this polymorphic gene in almond. 相似文献
953.
Crambe abyssinica is becoming a reliable source of industrial oil with good technical characteristics because of its high erucic acid content. The possibility of using the industrial defatted meal of crambe as a feed could further promote the interest in this crop, but is prevented by the high glucosinolate content (70‐150 μmol/g). Therefore the possibility of reducing this parameter by selection was evaluated and a search for a new quick analytical procedure begun. When hydrolysed by myrosinase (thioglucoside glucohydrolase EC 3.2.3.1.), at pH 6.5 or higher, epiprogoitrin, the main glucosinolate in crambe seed (>90% of total glucosinolates), gives (5R)‐5‐vinyl‐1,3‐oxazolidine‐2‐thione quantitatively. The latter can be easily estimated by high‐performance liquid chromatography. This is the background of the proposed analytical procedure that permits rapid analysis of about 100 samples per day using about 25 mg of crambe meal (five seeds) for assay. The method can also be used to select for glucosinolate content in rapeseed and, probably with some adjustment, all crops that have a 2‐hydroxy‐glucosinolate as the main glucosinolate. 相似文献
954.
Two participatory approaches to varietal selection were compared in February-sown (Chaite) rice and main-season rice in high potential production systems in Nepal. One method, called farmer managed participatory
research (FAMPAR), was researcher intensive, while the other, called informal research and development (IRD), demanded fewer
resources. The trials were conducted in 18 villages in high potential production systems in Chitwan and Nawalparasi districts
of Nepal. Six new varieties of Chaite rice and 16 of main-season rice were tested in over 300 trials of Chaite rice and nearly 1100 trials of main-season rice over two years in 1997 and 1998. Surveys were done in 1997, 1998 and 1999
to record the extent of adoption and spread of the new rice varieties in the study villages. In many cases, farmers tested
varieties for two years before deciding whether to adopt or drop them. Varieties were quite
widely accepted, adopted for niches in a few villages, or rejected. The two participatory approaches identified the same varieties,
but FAMPAR, which used formal survey methods, was more useful for diagnosing reasons for adoption or rejection. However, IRD
used much cheaper anecdotal methods of evaluation, so it was more cost-effective. Moreover,farmer-to-farmer seed dissemination
was higher in IRD villages, probably because farmers in FAMPAR villages felt that the project would re-supply seed if needed.
The benefits from both approaches are considerable, but to adopt them substantial policy changes in varietal testing, release
and extension systems will be required.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
955.
Sugarcane leaves and calli from highly susceptible and resistant varieties to eyespot disease were used to evaluate the Drechslera sacchari toxin effect at different concentrations and incubation times by measuring electrolyte leakage. This expression of disease resistance was observed not only in the leaf but also in the callus. Furthermore, the growth of resistant calli MS medium supplemented with DS toxin, was higher when compared to the susceptible ones. The possibility of obtaining resistant somaclones is confirmed. 相似文献
956.
Yue Hong Zheng Tikuan 《保鲜与加工》1989,(1):58-65
Being a kind of MWR, the orthogonal colloacation method can
be conveniently used to reduce the initial-boundary value problems of the partial differential equations to initial value problems of ordinary differential equations. In this paper, the orthogonal collocation method is introduced in detail and by using it the dynamic characteristics of a steam-water heater are investigated. 相似文献
957.
958.
Haitham Sayed Gunter Backes Hamed Kayyal Amor Yahyaoui Salvatore Ceccarelli Stefania Grando Ahmad Jahoor Michael Baum 《Euphytica》2004,135(2):225-228
A partial genetic linkage map was constructed on 71 doubled-haploid lines derived from a cross between the barley lines Tadmor
and WI2291 with 181 molecular markers. The segregating population was used to detect markers linked to the gene Mlg conferring resistance to powdery mildew (Erysiphe graminis f. sp. hordei) and to genes for quantitative resistance to scald (Rhynchosporium secalis). The gene Mlg on chromosome 4H was flanked by two AFLP markers at a distance of 2.0 and 2.4 cM, respectively. QTLs for resistance to scald
were detected on chromosomes 2H and 3H. This association of molecular markers with qualitative and quantitative disease resistance
loci represents a valuable starting-point for marker-assisted selection.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
959.
There are more than two power source in Hybrid Electrical Vehicle(HEV). By using of assist accelerating, power regeneration, Idle stop and power management, HEV gains more acceleration performance and more fuel economy and better gas emission than Conventional Vehicle(CV). With Integrated Starter and Generator(ISG) as a auxiliary power source, batteries and battery control module and power manage module as a Load leveling Device (LLD), two prototype HEV separately equipped Manual Transmission (MT) and Continuously Variable Transmission (CVT) was successfully developed. 相似文献
960.
Molecular mapping and characterization of traits controlling fiber quality in cotton 总被引:34,自引:1,他引:34
Cotton (Gossypium spp) is the world's leading natural fiber crop. Genetic manipulation continues to play a key role in the improvement of fiber
quality properties. By use of DNA-based molecular markers and a polymorphic mapping population derived from an inter specific
cross between TM-1 (G. hirsutum) and 3-79 (G. barbadense), thirteen quantitative trait loci (QTLs) controlling fiber quality properties were identified in 3-79, an extra long staple
(ELS) cotton. Four QTLs influenced bundle fiber strength, three influenced fiber length, and six influenced fiber fineness.
These QTLs were located on different chromosomes or linkage groups and collectively explained 30% to 60%of the total phenotypic
variance for each fiber quality property in the F2 population. The effects and modes of action for the individual QTLs were characterized with 3-79 alleles in TM-1 genetic
background. The results indicated more recessive than dominant, with much less additive effect in the gene mode. Transgressive
segregation was observed for fiber fineness that could be beneficial to improvement of this trait. Molecular markers linked
to fiber quality QTLs would be most effective in marker-assisted selection (MAS) of these recessive alleles in cotton breeding
programs.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献