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1.
The rates of organogenesis in all studied strains of Lupinus angustifolius L. were subject to increase at higher and to decrease at lower air temperatures and precipitation. The difference in the duration of the organogenesis phases between the standard Nemchinovsky 846 variety and those with reduced branching was in young crops (the second phase of organogenesis) reaching, on average, 7 days for the Ladny variety and 5 days for the Dikaf 14 variety.  相似文献   

2.
The conducted research has shown that acrotony characterizes the sort Nemchinovsky 846 and bazitony is usual for the sorts with unlimited branching. Concerning the sort Nemchinovsky 846, its auxiliary buds and shoots unfolded from them twice outnumber the auxiliary buds and shoots of the sort Ladny and 1.5 outnumber the sort Dikaf 14. The realization of buds into the shoots depended both on their location in the shoot system and on the weather conditions.  相似文献   

3.
 The aim of this study was to develop a cultivar identification tool based on molecular analysis and a statistical approach. From the PIC parameter we defined the D parameter, which evaluates the efficiency of a primer for the purpose of identification of varieties; i.e. the probability that two randomly chosen individuals have different patterns. D can be used to compare different types of markers even if only the allelic frequencies are known. We used this parameter to develop an algorithm for selecting the optimal combination of primers necessary to identify a set of varieties. The optimal combination of primers determined for a small elite group of varieties applied on a larger set induces a risk of confusion involving 1 of the elite varieties. We estimated the risk of confusion using the D value of each primer of the combination. We applied this methodology on a set of 224 varieties of Vitis vinifera screened with 21 RAPD primers and two microsatellite loci. The discriminating power of the primers did not only depend on the number of patterns it generates but also on the frequencies of the different patterns. A combination of 8 primers (6 RAPD and two microsatellite) was found to be optimum for the discrimination of these 224 varieties. A subset of 38 elite varieties was also investigated. The determined optimal combination of 4 primers (3 RAPD and one microsatellite) applied on the 224 varieties gave 9 risks of confusion involving 1 of the elite varieties. Confusion can happen between varieties with the same origin as well as between varieties of very diverse geographical origins. Received: 22 April 1998 / Accepted: 9 June 1998  相似文献   

4.
Race T1 of Phytophthora infestans was first isolated in Central Europe. Tomato varieties carrying the dominant gene Ph were easily infected by T1 but showed a different degree of field resistance. In September 1967 more than 80% of all isolations from the experimental plots at Greifswald were determined as the aggressive race T1. This race was also isolated in a large screening test over several provinces of the GDR from potato and tomato fields where no plants carrying dominant resistance genes were present in the neighbourhood. The fungus was able to pass from potato leaves or tubers to detached tomato leaves or intact tomato plants (cv. Fanal) without any reduction in sporulation. The field-resistant tomato variety Ru?ový Ker and the highly field-resistant variety Atom were crossed. In F2 and subsequent generations, young plants were selected following inoculation of 14 mm leaf-discs. Weak sporulations on the leaf-discs were almost invariably correlated with a reduced level of infection of fruit in the field. Data from crosses of Atom with more or less susceptible varieties suggested the presence of incompletely dominant genes. It is concluded that at least two genes in the variety Atom control field resistance and the gene-symbols Phf and Phf-2 are proposed for them.  相似文献   

5.
Laminaria longissima and Zaohoucheng No.1 (a commercial variety selected from Laminaria japonica) differ to a certain extent in their morphological characteristics and biological habits. It was assumed that varieties bred through their hybridization should exhibit high yield potential and tolerate relatively high seawater temperatures. Female gametophyte clones isolated from L. longissima were crossed with male clones isolated from Zaohoucheng No.1. Laminaria variety 90-1 was obtained after gametophyte crossing, continuous self-crossing and selection. This variety was genetically homozygous; the indices of variation of blade length, width and thickness of the final two selection cycles were 7–8%; i.e., not different significantly. Variety 90-1 grew faster, lost less tissue and had higher yield potential than two widely used commercial varieties of L. japonica (all commercial varieties currently used in China originate from this latter species). The blade of variety 90-1 increased 3.71 cm day−1 on average during the whole period of cultivation, almost two-fold that of two controls, and growth was maintained even when seawater temperature was higher than 18°C–3°C higher than the temperature tolerated by other Laminaria varieties. Variety 90-1 increased yield by more than 70% over two controls and also synthesized desirable amounts of iodine, mannitol and algin. In blade length, variety 90-1 was more similar to L. longissima than to L. japonica, but more similar to L. japonica in blade width and thickness. Since the adoption of variety 90-1 in 1999, its culturing area has increased each year to reach its current area of 7,000 ha, i.e., almost one-third of the total cultivation acreage of Laminaria in China. Breeding of variety 90-1 has demonstrated that it is feasible to develop elite Laminaria varieties by crossing gametophytes from different Laminaria species in combination with successive self-crossing and selection.  相似文献   

6.
Jatropha curcas L., a multipurpose shrub, has acquired significant economic importance for its seed oil which can be converted to biodiesel an emerging alternative to petro-diesel. In addition to the commercial value, it is also having medicinal and even high nutritional value to use as animal fodder which is limited due to the toxicity. Development of molecular marker will enable to differentiate non-toxic from toxic variety of J. curcas in a mixed population and also for quality control since the toxic components of J. curcas has deleterious effect on animals. In the present study, the efforts were made to generate the specific SCAR marker for toxic and/or non-toxic J. curcas from RAPD markers. Among the markers specific for toxic and non-toxic varieties, four were selected, purified, cloned, sequenced, and designed primers out of which one set of primers NT-JC/SCAR I/OPQ15-F and R could able to discriminate the non-toxic with toxic Jatropha by giving expected 430 bp size amplification in non-toxic variety. Furthermore, novel multiplex PCR was designed using the nrDNA ITS primers to overcome the false negatives. Present work also demonstrates utility of the conserved regions of nrDNA coding genes in ruling out the artifacts in PCR-like false negatives frequently occur in SCAR due to various reasons. The specific SCAR markers generated in the present investigation will help to distinguish non-toxic from toxic varieties of J. curcas or vice versa, and isolated marker along with designed multiplex protocol has applications in quality control for selective cultivation of non-toxic variety and will also assist in breeding and molecular mapping studies.  相似文献   

7.
The mango, a virtually neglected fruit before the advent of nitrate-induced flowering, is now the third leading export fruit in the Philippines, with the ‘Carabao’ mango being the only variety exported. Delay or control of ripening, as well as the ability to program market availability, would further increase the value of mango. Prolonging its shelf life and improving other characteristics can be achieved through biotechnology, requiring a reliable tissue culture regeneration protocol, and a successful transfer-to-soil system. Between 2004 and 2008, immature fruits were collected and cultured in vitro. Primary somatic embryo (SE) induction ranged from 16–100% depending on the strain, collection time, and tree source. A single SE was required to initiate SE proliferation. When subcultured, the SEs proliferated, germinated, and produced plantlets. Initial shoot formation was 8–64%, while succeeding true leaf formation was reduced to 0–36%. In some cultures, abscission and browning were observed, but gas chromatography assays ruled out ethylene as the cause. Regenerated plants survived transfer to soil, but at low percentages. While it took 1 y to develop the tissue culture protocol, it took 3 y to develop the technique for successful transfer of plantlets to soil, and to the field. This is the first report, of a polyembryonic mango, variety Carabao, for which successful tissue culture and field transplantation systems were developed. The technology is equally important as a way to rapidly propagate uniform rootstocks of superior ‘Carabao’ strains or other varieties, for generation of variability, genetic transformation, and for germplasm conservation and exchange.  相似文献   

8.
Thomas TR  Shackel KA  Matthews MA 《Planta》2008,228(6):1067-1076
Vitis vinifera L. berries are non-climacteric fruit that exhibit a double sigmoid growth pattern and dynamic changes in gene expression, cell metabolism, and water relations at the onset of ripening. The cell-pressure probe was utilized to examine the relationships of turgor pressure (P) in mesocarp cells to growth, sugar accumulation, and fruit softening during development. In replications utilizing three different varieties, mesocarp cell P demonstrated a consistent pattern of a relative mid-range P early in development, followed by an increase to a maximum of about 0.35 MPa, and a subsequent rapid decline before ripening to less than 0.1 MPa. Fruit “apparent elastic modulus” (E, units of MPa), was introduced as a standard measure to describe ripening-related softening. E changed dynamically and synchronously with P during development and in response to water deficits for fruit grown in greenhouse and field conditions. Thus, E and P were positively and linearly related. Sugar accumulation did not increase significantly until P had declined to less than 0.1 MPa. The results suggest that P is an important determinant of fruit softening and that P decreases in conjunction with many of the physiological and gene expression changes that are known to occur at the onset of ripening. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

9.
The rate of entry by neonate larvae of the frugivorous codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), into fruit material was investigated. We used no‐choice bioassays in climate‐controlled rooms to assay larval entry across four host plant species (apple, pear, quince, walnut) and three varieties within a single fruit species (apple). Larvae successfully entering apples were reared to adulthood, and we collected tissue samples from apples which were successfully colonized in order to determine sucrose concentrations. This information was used to evaluate differences in adult moth size, development time, and pulp sucrose concentration due to apple variety. Four important findings emerged: (1) neonate larvae had the highest frequency of entry (86% of larvae) into apple fruits, compared with pear (78%), quince (56%), and walnut (32%); (2) the frequency of larval entry into immature apples differed across apple varieties, and larval entry rate was highest in variety Golden Delicious (72%), compared with Granny Smith (46%) and Red Delicious (64%); (3) on average, adult moths were larger and development times were shorter on the variety with the highest entry frequency (Golden Delicious); and (4) apple pulp sucrose concentrations were higher for Golden Delicious (17.5 μg mg?1) than for either Granny Smith (15.9 μg mg?1) or Red Delicious (15.1 μg mg?1) varieties, which correlates positively with entry and development data. We conclude that host fruit species and varietals within a species affect the entry rate of neonate codling moth larvae in no‐choice assays. We hypothesize that larval development is influenced by mean sucrose concentrations or other phytochemical differences associated with host fruit varieties.  相似文献   

10.
A set of 171 recombinant inbred lines (RIL) were developed from a narrow cross in cucumber (Cucumis sativus L.; 2n = 2x = 14) using the determinate (de), gynoecious (F), standard-sized leaf line G421 and the indeterminate, monoecious, little-leaf (ll) line H-19. A 131-point genetic map was constructed using these RILs and 216 F2 individuals to include 14 SSRs, 24 SCARs, 27 AFLPs, 62 RAPDs, 1 SNP, and three economically important morphological [F (gynoecy), de (determinate habit), ll (little leaf)] markers. Seven linkage groups spanned 706 cM with a mean marker interval of 5.6 cM. The location of F and de was defined by genetic linkage and quantitative trait locus (QTL) analysis to be associated with SSR loci CSWCT28 and CSWCTT14 at 5.0 cM and 0.8 cM, respectively. RIL-based QTL analysis of the number of lateral branches in three environments revealed four location-independent factors that cumulatively explained 42% of the observed phenotypic variation. QTLs conditioning lateral branching (mlb1.1), fruit length/diameter ratio (ldr1.2) and sex expression (sex1.2) were associated with de. Sex expression was influenced by three genomic regions corresponding to F and de both on linkage Group 1, and a third locus (sex6.1) on linkage Group 6. QTLs conditioning the number of fruit per plant (fpl1.2), the number of lateral branches (mlb1.4) and fruit length/diameter ratio (ldr1.3) were associated with ll. The potential value of these marker-trait associations (i.e., yield components) for plant improvement is portended by the relatively high LOD scores (2.6 to 13.0) and associated R2 values (1.5% to 32.4%) that are affiliated with comparatively few genetic factors (perhaps 3 to 10).Communicated by H.C. BeckerMention of trade name, proprietary product, or specific equipment does not constitute a guarantee or warranty by the USDA and does not imply its approval to the exclusion of other products that may be suitable  相似文献   

11.
Natural fruit set is constrained by pollen limitation and fruiting failure, and pollen limitation is expected to be especially severe in deceptive orchids. We performed hand cross‐pollinations in ten populations of a food‐deceptive orchid, Calypso bulbosa, under sparse and dense canopies in three non‐consecutive years. We explored the relationships between natural fruit set, pollen limitation and fruiting failure. Mean natural fruit set over the years was 60%, which is exceptionally high for a deceptive orchid. On average, hand cross‐pollination increased fruit set by 23%. Among open‐pollinated plants that did not set a fruit, 55.5% were estimated to be pollen limited and 44.5% to be limited by fruiting failure, i.e. inability to set a fruit after pollination. In species with high natural fruit set, hand cross‐pollination experiments may not always detect statistically significant pollen limitation. In our case, pollen limitation tended to become significant when the natural fruit set dropped below 60%. Canopy cover had a significant effect on fruiting failure, which was more severe under a dense canopy. Although our results demonstrate pollen limitation in many cases, they also highlight the fact that food deception can be a very effective pollination strategy. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013 , 171 , 744–750.  相似文献   

12.
Low fruit set is common in many plant species and may be caused by a variety of factors, such as predation, resource limitation or deficient pollination, or it may be an evolutionary strategy. In this paper, we investigate factors that affect fruit set in Aristolochia baetica (Aristolochiaceae), a Mediterranean pipevine found in southwest Spain. Fruit production was monitored in two populations over 4 years (2002-2005), and the causes of flower or fruit loss were determined. Experimental hand-pollinations were performed, and germinated pollen grains on the stigmas of open-pollinated flowers were quantified. Fruit set was always very low (4-14%). Floral abscission initially reduced reproductive output by more than 50%; then herbivory (6-12%) and fruit abortion (8-26%) caused further reductions. Given that the number of efficiently pollinated flowers was always higher than that of ripe fruits, and that xenogamous hand-pollination did not increase fruit set in relation to open-pollination, the final fruit production of A. baetica seems not to be pollen-limited. Fruit abortion of effectively pollinated flowers supports the idea that resource availability limits fruit set. In A. baetica, fruit abortion could lead to mate selection of the best quality fruits. Moreover, the initiated fruits that finally abort could also satiate predators, contributing to increase progeny fitness.  相似文献   

13.
Breeders can force sexual hybridisation between wheat and related grass species to produce interspecific hybrids containing a dihaploid set of wheat and related chromosomes. This facilitates the introgression of desirable genes into wheat from the secondary gene pool. However, most elite European wheat varieties carry genes that suppress crossability, making the transfer of novel traits from exotic germplasm into elite wheat varieties difficult or impossible. Previous studies have identified at least five crossability loci in wheat. Here, the crossability locus with the largest effect, Kr1 on chromosome arm 5BL, was fine-mapped by developing a series of recombinant substitution lines in which the genome of the normally non-crossable wheat variety ‘Hobbit sib’ carries a recombinant 5BL chromosome arm containing segments from the crossable variety ‘Chinese Spring’. These recombinant lines were scored for their ability to cross with rye over four seasons. Analysis revealed at least two regions on 5BL affecting crossability, including the Kr1 locus. However, the ability to set seed is highly dependent on prevailing environmental conditions. Typically, even crossable wheat lines exhibit little or no seed set when crossed with rye in winter, but show up to 90% seed set from similar crosses made in summer. By recombining different combinations of the two regions affecting crossability, wheat lines that consistently exhibit up to 50% seed set, whether crossed in the UK winter or summer conditions, were generated, thus creating a very important tool for increasing the efficiency of alien wheat transfer programmes.  相似文献   

14.
The breeding of japonica varieties with erect-pose panicle (EP) has recently progressed in the northern part of China, because these varieties exhibit a far higher grain yield than the varieties with normal-pose panicle (NP). A genetic analysis using the F2 population from the cross between Liaojing5, the first japonica EP variety in China, and the Japanese japonica NP variety Toyonishiki revealed that EP is governed by a single dominant gene EP. Based on previous studies, map-based cloning of EP locus was conducted using Liaojing5, Toyonishiki, their F2 population, and a pair of near-isogenic lines for EP locus (ZF14 and WF14) derived from the cross between the two varieties; consequently, the STS marker H90 was found to completely cosegregate with panicle pose. The H90 is located in the coding sequence AK101247 in the database, and the AK101247 of Liaojing5 has a 12 bp sequence in exon 5 replaced with a 637 bp sequence of its wild type allele. It was therefore considered that the AK101247 encodes the protein of the wild type allele at EP locus, and that the sequence substitution in exon 5 of Liaojing5 is crucial for expression of the EP phenotype. The effects of EP gene on agronomic traits were investigated using two pairs of near-isogenic lines (ZF6 vs. WF6 and ZF14 vs. WF14) derived from the cross between the two varieties. Experimental results showed that EP gene markedly enhanced grain yield, chiefly by increasing number of secondary branches and number of grains on the secondary branch. EP gene also produced a remarkable increase in grain density.  相似文献   

15.
16.
17.
Infestation-damage relationship for the host-parasite system wheat-Septoria nodorum Berk. It was the aim of these investigations to elucidate the relationship between infestation by Septoria nodorum Berk. and the damage caused thereby to the winter wheat varieties grown in the GDR. In 1983 and 1984 the varieties Alcedo and Taras were tested, and for the identification of typical varietal reactions, another 4 cultivars (Arkos, Compal, Mironovskaya 808 und Ilyitshovka) were included, in 1984. Artificial inoculation was carried out when the ears were emerging, using spore suspensions of varying density to achieve various degrees of infestation. For each variety, ear and flag leaf infestations were recorded on 800 culms and these were thengrouped into the categories I, II and III according to the number of points they had received (9 = without any infestation, 7 and 5 = number of points decreasing as infestation increased). Altogether 5–6 assessments were made, with the points given at the growth stage “beginning of the milky ripeness” being used as the basis for the calculation of the infestation-damage relationship. The most important criterion for each group was the mean single ear weight, the 1000-grain weight and the number of grains per ear, were also taken into consideration. Comparing ear infestation with yield it can be stated that the variety Compal and the early ripening Soviet varieties Mironovskaya 808 and Ilyitshovka showed relatively low losses. The variety Taras ranked in the middle. Alcedo and Arkos suffered the highest yield losses. Depending on the variety, an infestation level rated with 7 points at the beginning of milky ripeness implied yield losses of 5–13 %, whereas a 5 rating point would represent losses of 13–23 %. The results obtained make it clear that the wheat cultivars tested were not damaged by S. nodorum to the same degree, indicating differing varietal susceptibility, which does not allow a generalization with respect to the infestation-damage relationship for the host-parasite pair wheat-S. nodorum.  相似文献   

18.
Outbreeding confers an evolutionary advantage, and flowering plants have evolved a variety of contrivances for its maximization. However, neither fruit set nor seed set is realized to its fullest potential for a variety of reasons. The causes of low flower to fruit and seed to ovule ratios were investigated in naturally occurring bael trees (Aegle marmelos) at two sites for three seasons. The study established that the mass effect of synchronized flowering attracted a variety of insect pollinators to the generalist flowers; Apis dorsata was the most efficient pollinator. The seed to ovule ratio was low despite high natural pollination efficiency (c. 2400 pollen per stigma). Although pollination‐induced structural and histochemical changes in the style allowed many (9.5 ± 2.1) pollen tubes to grow, only cross‐pollen tubes could grow through the style. Gametophytic self‐incompatibility, manifested in the stylar zone, resulted in a significantly slower growth rate of self‐pollen tubes. The occurrence of obligate self‐incompatibility, coupled with increased self‐pollen deposition (geitonogamy), caused a significant number of flowers to abort. Fruit retention in the trees declined from 40% to 12% as a result of abortion of fruits at different stages of development. The number of mature fruits on a tree was negatively correlated (r = ?0.82) with their size. It is inferred that low natural fecundity in A. marmelos is primarily a result of obligate self‐incompatibility and strong post‐fertilization maternal regulation of allocation of resources to the developing fruits. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 172 , 572–585.  相似文献   

19.
不同产地山桐子果实含油率及其理化指标变异分析   总被引:3,自引:0,他引:3  
以13个产地居群的山桐子果实为材料,测定其全果含油率,并选取5个居群的果实分别测定果肉、种子含油率进行变异分析。结果表明:(1)13个居群间山桐子果实含油率差异显著,四川各居群山桐子果实含油率明显大于其他地区,各个居群内果实含油率差异明显,极端变异程度较大。(2)5个居群山桐子果肉含油率均大于种子含油率,而果肉含油率变异系数及相对极差均小于种子。(3)聚类分析结果显示,朝天等7个居群聚为一类,其果实含油率较高,变异系数较小,可以作为进一步良种选育的材料;海拔等地理因素对山桐子果实含油率均有一定影响,但程度不一。(4)5个居群山桐子果实油脂折光率均较高,而酸值均较低,表明山桐子油品质好,纯度较高,而且不同居群山桐子油碘值差异显著,反映其油脂不饱和程度差异明显。  相似文献   

20.
Metabolic fingerprinting of salt-stressed tomatoes   总被引:20,自引:0,他引:20  
The aim of this study was to adopt the approach of metabolic fingerprinting through the use of Fourier transform infrared (FT-IR) spectroscopy and chemometrics to study the effect of salinity on tomato fruit. Two varieties of tomato were studied, Edkawy and Simge F1. Salinity treatment significantly reduced the relative growth rate of Simge F1 but had no significant effect on that of Edkawy. In both tomato varieties salt-treatment significantly reduced mean fruit fresh weight and size class but had no significant affect on total fruit number. Marketable yield was however reduced in both varieties due to the occurrence of blossom end rot in response to salinity. Whole fruit flesh extracts from control and salt-grown tomatoes were analysed using FT-IR spectroscopy. Each sample spectrum contained 882 variables, absorbance values at different wavenumbers, making visual analysis difficult and therefore machine learning methods were applied. The unsupervised clustering method, principal component analysis (PCA) showed no discrimination between the control and salt-treated fruit for either variety. The supervised method, discriminant function analysis (DFA) was able to classify control and salt-treated fruit in both varieties. Genetic algorithms (GA) were applied to identify discriminatory regions within the FT-IR spectra important for fruit classification. The GA models were able to classify control and salt-treated fruit with a typical error, when classifying the whole data set, of 9% in Edkawy and 5% in Simge F1. Key regions were identified within the spectra corresponding to nitrile containing compounds and amino radicals. The application of GA enabled the identification of functional groups of potential importance in relation to the response of tomato to salinity.  相似文献   

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