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1.
Celso Lopes de Albuquerque Frederico Denardi Adriana Cibele de Mesquita Dantas Rubens Onofre Nodari 《Euphytica》2011,181(2):277-284
Apple plants are self-incompatible because a genetic mechanism allows the female reproductive organ to recognize and reject
self-pollen or pollen from genetic related individuals and allows non-self pollen to effect fertilization. Thus, there are
implications to both breeding strategies and orchard management for fruit production. The purpose of this study was to identify
and to characterize the S-RNase alleles of the gametophytic incompatibility among apple cultivars developed in Brazil, seeking
to give support for choosing right combinations of parent in the apple breeding programs. It also sought to identify correct
combinations of scion/pollinator cultivars of commercial apple orchards. A total of 16 specific S-RNase alleles primers were
tested against DNA extracted from 12 Brazilian cultivars and their parents. The molecular analysis confronted to the reference
cultivars, showed that the cultivars Daiane, Imperatriz and Princesa have the same incompatibility S3 and S5 alleles, while
‘Lisgala’ showed the alleles S2 and S5; ‘Suprema’, S1 and S9; ‘Catarina’, S1 and S19; ‘Joaquina’ and ‘Fred Hough’, S5 and
S19; ‘Baronesa’, S3 and S9; ‘Duquesa’, S2 and S3. For ‘Primícia’ and ‘Condessa’ it was only possible to identify one of the
S-alleles, namely S24 and S2, respectively, with the second allele remaining to be identified. Progeny test indicated the
Mendelian inheritance for RNase alleles. Results of this study will be helpful to judiciously choose parents in apple breeding
programs to improve compatibility. 相似文献
2.
Proteins were extracted from styles of 29 self-incompatible cultivars of almond and separated using non-equilibrium pH gradient
electro-focusing, and the gels were stained for ribonuclease activity. Mutually incompatible cultivars had similar banding
patterns and, for the 24 cultivars already genotyped in France or California, the bands correlated well with the reported
alleles. The band corresponding to S1 of the French labelling system was indistinguishable from that corresponding to Sb of the Californian labelling system, and a controlled cross confirmed that these alleles are identical. The band corresponding
to the Californian Sa was distinct from the bands corresponding to French alleles and, to harmonise the allele labels, it was redesignated S5. The genotypes of five uncharacterised self-incompatible cultivars were inferred from zymograms as follows: ‘Desmayo Largueta’
and ‘Glorieta’, S1S5, ‘Masbovera’, S1S9, ‘Tarragones’, S2S9, and ‘Tokyo’, S6S7. The alleles designated S6 and S9 have not previously been reported. Nine self-compatible cultivars or selections were analysed, and each showed a band corresponding
to an incompatibility allele as well as a common band; however, the correspondence of this common band to Sf, the allele for self-compatibility, is unproven.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
3.
Identification and genetic characterization of different resistance sources to ascochyta blight within the genus Lens 总被引:2,自引:0,他引:2
The self-incompatibility mechanism in 10 local radish cultivars was investigated through seed set analysis and pollen tube
growth behavior. The objective was to identify self-incompatible local radish lines for hybrid seed production. Based on a
seed set ratio as an estimate for self-incompatibility, cultivars Tangail Local, Tasaki, Kuni, Aushi and Indian Aushi were
identified as self-compatible. An intermediate seed ratio was observed in ‘Red Mollika’, ‘Pinky’ and ‘Red Bongi’. Moderately
strong self-incompatibility was observed in ‘Red Kalpin’ and ‘Kuni White’. Pollen tube growth behavior revealed that self-incompatible
lines had a relatively lower number of germinated pollen grains per stigma and pollen tubes per style than those of self-compatible
lines. The two self-incompatibility test methods gave comparable results. None of the cultivars under study was found to be
fully self-incompatible.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
The development of triploid cultivars from crosses between the tetraploid landrace ‘Morado de Huetor’ and diploid commercial
cultivars was studied in this work. Fertility of both 4x × 2x and 2x × 4x crosses, as measured by fruit set and number of
seeds per fruit, and germination rate of triploid seeds, were studied in order to assess the viability of producing commercial
seeds. Seven triploid hybrid progenies were included in a progeny test together with thirteen experimental tetraploid hybrids
and four cultivars (‘Grande’, ‘UC157-F2’, ‘Purple Passion’ and ‘Morado de Huetor’). Marketable spear production and mean diameter
of spears were evaluated in both 2007 and 2008. Crosses 4x × 2x were more successful than 2x × 4x, and a wide variation from
high to very low fertility within tetraploid females was found. Germination rate of triploid seeds was similar to diploid
ones. After 2 years of evaluation experimental hybrid triploids were more productive than tetraploids with values similar
to the highest yielding diploid cultivar (‘Grande’). Spear diameter of triploid hybrids was in general thicker than the tetraploid
hybrids and significantly thinner than the standard cultivars ‘Grande’ and ‘Purple Passion’ (tertraploid). These results suggest
that the development of new triploid cultivars (4x × 2x) employing a tetraploid landrace from a different genetic background
of current diplods could be interesting in asparagus breeding, broadening the spectrum of cultivated asparagus cultivars. 相似文献
5.
Shigeki Moriya Hiroshi Iwanami Kazuma Okada Toshiya Yamamoto Kazuyuki Abe 《Euphytica》2011,177(1):135-150
Differentiation of cultivars with simple sequence repeat (SSR) markers is a very useful technique for the true-to-type characterization
of cultivars and clarification of parent-offspring relationships. We developed an SSR marker set for cultivar identification
comprising 15 markers that were screened from 46 previously published SSRs. This marker set could be used for apple varieties
including Malus × domestica and/or other Malus species. These SSRs successfully characterized 95 apples, including the leading and major founding cultivars used worldwide
for modern apple breeding. Therefore, this marker set could be applied to almost all apple cultivars. We also analyzed the
parent-offspring relationships of 69 cultivars by considering allele transmissions. This analysis revealed the true parentage
of the following seven cultivars: ‘Kizashi’, ‘Chinatsu’, ‘Honey Queen’, ‘Haruka’, ‘Seirin’, ‘Ozenokurenai’, and Morioka #48.
This analysis also revealed a parentage discrepancy for ‘Hacnine’. From the parent-offspring analysis, two microsatellite
mutation events at alleles inherited from pollen parents were observed. 相似文献
6.
Coconut foliar decay (CFD) is a disease of coconut (Cocos nucifera L.) associated with infection by coconut foliar decay virus (CFDV), which is endemic in Vanuatu, South Pacific. The local
cultivar ‘Vanuatu Tall’ (VTT) is the only cultivar that is fully tolerant to CFD, whereas introduced cultivars and hybrids
are affected to different degrees. From 1967 to 2008 a conventional breeding programme was conducted with the aim of creating
hybrid planting material combining tolerance to CFD with improved copra yield and high copra weight per nut. This objective
was achieved by crossing the progeny of selfed trees of ‘Rennell Island Tall’ (RIT) cultivar, selected for their low susceptibility
to CFD in field screening tests, with VTT, improved by mass selection and intercrossing. An improved VTT × RIT hybrid was
identified with a high degree of tolerance to CFD (less than 1% of diseased trees after 11 years of exposure to high disease
pressure). The annual production of the improved VTT × RIT hybrid ranged from 21.9 to 28.6 kg of copra per tree, depending
on the RIT parent, and was, on average, 34% higher than that of ‘VTT Elite’ an advanced cultivar obtained after four selection
cycles of local VTT. However, the production of the hybrid in Vanuatu involves constraints such as frequent replanting and
isolation of the seed garden and CFD control for the RIT parents. The importance of conducting research on the genetic determinism
and the mechanism of tolerance to CFD for better control of the disease in the event that it spreads outside Vanuatu is discussed. 相似文献
7.
Heterosis and inbreeding depression for fruit yield has been reported for pickling cucumber (Cucumis sativus L.). However, cucumber inbreds often perform as well as hybrids, and there is little inbreeding depression. The objectives
of this study were to reexamine the amount of heterosis and inbreeding depression for fruit yield and yield components in
pickling cucumber, and to determine the relationship between yield components and yield for heterosis. Two pickling cucumber
inbreds (M 12, M 20) and inbreds from four open-pollinated monoecious cultivars (‘Addis’, ‘Clinton’, ‘Wisconsin SMR 18’, ‘Tiny
Dill’) were hybridized to form four F1 hybrids (‘Addis’ × M 20, ‘Addis’ × ‘Wis. SMR 18’, ‘Clinton’ × M 12, M 20 × ‘Tiny Dill’). F1 hybrids were then self-pollinated or backcrossed to generate F2, BC1A, and BC1B progeny. Thirty plants of each generation within each hybrid family were grown in plots 3.1 m long with four replications
in each of two seasons. Data were collected from once-over harvest for vegetative, reproductive, yield, and fruit quality
traits. Heterosis and inbreeding depression for fruit yield and yield components were not observed in three of the hybrids.
Only ‘Addis’ × ‘Wis. SMR 18’ exhibited high-parent heterosis and inbreeding depression for total, marketable, and early fruit
weight. For ‘Addis’ × ‘Wis. SMR 18’, heterosis for fruit yield was associated with a decreased correlation between percentage
of fruit set and fruit weight, an increased negative correlation between percentage of fruit set and both the number of branches
per plant and the percentage of pistillate nodes, and an increased negative correlation between the number of nodes per branch
and total fruit weight. Inbreeding depression was associated with a weakening of the strong negative correlations between
percentage of fruit set and the number of branches per plant, and between the number of nodes per branch and total fruit weight.
Those correlations were associated with high-parent heterosis and inbreeding depression only for one cross, and do not necessarily
apply to future crosses in which heterosis may be observed for yield. We did not observe the heterosis or inbreeding depression
for yield in cucumber in most of the crosses as was reported by Ghaderi & Lower (1979a; 1979c).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
8.
Sarika Mathure Asif Shaikh N. Renuka Kantilal Wakte Narendra Jawali Ratnakar Thengane Altafhusain Nadaf 《Euphytica》2011,179(2):237-246
Eighty-eight aromatic cultivars collected from Maharashtra state were assessed for determinants of kernel quality (kernel
size-shape, test weight and aroma) and grain morphology such as awning, lemma and palea characters, pubescence, colour of
sterile lemma and apiculus colour. We, report seven cultivars—‘Girga’, ‘Kothmirsal’, ‘Kala bhat’, ‘Chimansal’, ‘Jiri’, ‘Kalsal’
‘Velchi’ and ‘Kali kumud’ as indigenous to southern India. Of the 69 cultivars characterized for agronomic traits 36 cultivars
were exquisite genotypes and possessed one or more superior traits such as early flowering, dwarf stature, higher number of
productive tiller per plant; long panicles; higher number of filled grains per panicle and strong aroma. Variability in aromatic
cultivars was assessed on the basis of nine traits placed aromatic rice cultivars in five clusters. Number of cultivars in
each cluster ranged from 1 to 33. 27 significant correlations were obtained in the physical, agronomic and grain morphology
traits. Aroma was found to be negatively associated with days to 50% flowering as well as with filled grains per panicle.
However, correlation between panicle length and effective tillers with aroma was not observed. Therefore, to increase the
yield, improvement in length of panicle and increasing number of productive tillers in medium or mild scented cultivars would
be the best strategy. 相似文献
9.
Identification of citrus hybrids through the combination of leaf apex morphology and SSR markers 总被引:5,自引:0,他引:5
Antonio Carlos de Oliveira Aristides Novac Garcia Mariângela Cristofani Marcos Antônio Machado 《Euphytica》2002,128(3):397-403
Citrus breeding programs normally face several biological obstacles such as apomixis and polyembryony that result in a cumbersome
identification of hybrid seedlings. The main purpose of this work is to describe the combined use of visual selection based
on the leaf apex morphology and SSR analysis to differentiate hybrid from nucellar seedlings derived from the cross between
the ‘Murcott’ tangor [Citrus reticulata Blanco × Citrus sinensis (L.) Osb.] and ‘Pêra’ sweet orange [Citrus sinensis(L.) Osb.]. A new morphological variable named leaf apex morphometric index is also described as the quantitative basis of
the visual selection. The efficiency of visual selection of hybrids was tested under two growth conditions, seedlings germinated
in seedbeds and in plastic tubes. Putative hybrid seedlings were also confirmed through the analysis of simple sequence repeats
(SSR). The visual selection of hybrid seedlings resulted in an increase of 87.2% (p < 0.01) and 202.2% (p <0.001) in the number of correctly identified hybrids when compared to the method of random picking of seedlings in seedbeds
and plastic tubes,respectively. The results indicate that the combination of visual selection and SSR analysis for the identification
of hybrids derived from the cross of polyembryonic citrus cultivars will improve the accuracy of the selection,save time,
and reduce the costs involved in the use of molecular markers alone in citrus breeding programs.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
10.
Genotypes for the glume colour character have been studied in 27 cultivars of common wheat (Triticum aestivum L.) originated
from old landraces, and 1 specimen of T. petropavlovskyi Udacz. et Migusch. by means of analysis of the F2 populations. The following tester lines have been used: white-glumed ‘Novosibirskaya 67’ ‘Diamant I’, and ‘Federation’, carrying
the Rg1 gene alone; lines RL5405 and near-isogenic ‘Saratovskaya 29’ *5 (T. timopheevii Zhuk./T. tauschii (Coss.) Schmal.),
carrying Rg2; line (1A ‘CS’ × ‘Strela’) with Rg3. The red glume colour in 21 cultivars of Triticum aestivum and in the accession
of T. petropavlovskyi has been shown to be determined by the single gene Rg1, located on chromosome 1B. Five cultivars carrying
the gene Rg3 for red glumes on chromosome 1A have been revealed. The cultivars ‘Zhnitsa’ and ‘Iskra’ carry the gene Rg3 alone.
The red glume colour in the cultivars ‘Milturum 321’, ‘Milturum 2078’, ‘Sredneural'skaya’ is controlled by two genes, Rg1
and Rg3. In two common wheat cultivars, ‘Sarrubra’ and ‘Krasnoyarskaya 1103’ the red glume colour is determined by Rg1, inherited
from local populations (‘Turka’ and ‘Kubanka’ respectively) of tetraploid wheat T. durum Desf. var. hordeiforme Host. Wide
occurrence of the Rg1 gene in common wheat has been confirmed. On the contrary, none of the investigated varieties carries
the gene Rg2.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
11.
Salvador Becerra-Rodríguez Víctor Manuel Medina-Urrutia Marciano Manuel Robles-González Timothy Williams 《Euphytica》2008,164(1):27-36
Grapefruit growers in the tropics require information about existing and new citrus cultivars with high productivity potential.
The objective of this study was to determine the growth, yield, and fruit quality performance of seven pigmented and four
white grapefruit cultivars under the dry tropic conditions of Colima, Mexico. The trees were budded on sour orange (Citrus aurantium L.) rootstock and planted at a distance of 8 × 4 m. ‘Oroblanco’ and ‘Marsh Gardner’ white-fleshed grapefruit cultivars and
‘Chandler’, a pink-fleshed pummelo, were the largest trees with the greatest height (5.0–5.6 m), canopy diameter (6.2–6.3 m),
trunk diameter (21.9–23.3 cm), and canopy volume (109–123 m3). Lower height (4.3–4.8 m) and canopy volume (73–96 m3), but with similar canopy diameter to the previously mentioned cultivars, were recorded for the remaining pigmented cultivars.
‘Chandler’ pummelo and four pigmented grapefruit cultivars (‘Shambar’, ‘Río Red’, ‘Ray Ruby’, and ‘Redblush #3’) had yearly
productions of 34.8, 34.9, 34.1, 32.7, and 30.6 ton ha−1, respectively. The most productive white grapefruit cultivar was ‘Marsh Gardner’ (30.5 ton ha−1). Grapefruit cultivars having the largest fruit size showed a higher inverse relationship between fruit weight and yield
than those with small fruit. Most genotypes had higher values of fruit weight, juice content, and maturity index than those
required by the local market. The most promising grapefruit cultivars based on their acceptable growth, yield superior to
30 ton ha−1, and acceptable fruit color were ‘Río Red’, ‘Shambar’, ‘Ray Ruby’, and ‘Redblush #3’. 相似文献
12.
Genetic characterization and identification of new accessions from Syria in an olive germplasm bank by means of RAPD markers 总被引:4,自引:0,他引:4
Angjelina Belaj Juan M. Caballero Diego Barranco Luis Rallo Isabel Trujillo 《Euphytica》2003,134(3):261-268
Thirty-two olive cultivar accessions from Syria, most of them obtained from collecting expeditions, were characterized by
means of RAPD markers before being introduced in the World Germplasm Bank of Cordoba. A total of 79 polymorphic bands(6.1
polymorphisms per primer) out of 93(7.1 bands per primer) were scored for the13 primers used, corresponding to 84.9% of the
amplification products. Thirty-one different genotypes were clearly discriminated. Differences were not found among the amplification
profiles from different individuals of the same cultivar. Only two cases of mislabeling or errors of planting were found.
Fourteen accessions corresponding to 6 homonyms were discriminated by RAPDs as different genotypes. The dendrogram obtained
by RAPD analysis included three major groups. Some evidence of relationships of the Syrian accessions studied according to
their geographic origin and/or diffusion was found. For instance, cultivars from the Central Syria (Tadmur/Palmyra)such as
Toffahi', ‘Abbadi Abo Gabra’-1033,‘Abo Kanani’, ‘Shami’-1041, ‘Abbadi Shalal’ ‘Adgam’-844 and ‘Majhol’-1013 clustered in Group
1 and 2. Six cultivars from Northern Syria clustered in Group 2. But it was not found a geographic structure for the cultivars
from South and West of Syria. These results agree with the hypothesis of autochthonous origin of most of the olive cultivars.
Some associations between cultivars from Central Syria and their fruit size were observed. This suggests that fruit size was
a criterion of local selection in olive cultivars of this area.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
13.
In this study, Tulipa fosteriana was found to contain 45S rDNA repeat units of 9.7 and 9.5 kb, in which at least 7 types of 45S rDNAs were identified by restriction
site analysis. For 5S rDNA, repeat units ranging from 364 bp to 396 bp were identified. The diploid cultivars (2n = 2x = 24)
‘Christmas Dream’ and ‘Queen of Night,’ representing the horticultural group T. gesneriana, and ‘Red Emperor’, belonging to T. fosteriana, were compared cytogenetically using cloned 5S and 45S rDNAs. Fluorescence in situ hybridization (FISH) analysis identified
many rDNA sites located on each chromosome in the diploid genomes. For example, we identified 71 sites of 5S rDNA and 10 sites
of 45S rDNA in ‘Red Emperor’. Additionally, FISH analyses enabled construction of karyotypes for these cultivars. Karyotype
comparison of T. gesneriana cultivars showed conservation of repetitive rDNA unit positioning. A clear difference in chromosome size and signal pattern
was observed between T.
gesneriana and T.
fosteriana cultivars. Here we demonstrate the unique nature of the highly repeated 5S rDNA units in these Tulipa species and the usefulness of FISH karyotyping with cloned 5S and 45S rDNAs to clearly distinguish between chromosomes from
T. gesneriana and T. fosteriana.
Hitoshi Mizuochi and Agnieszka Marasek contributed equally to this paper 相似文献
14.
Optimal carbamate treatment conditions were studied for flower induction in seedlings of an asparagus cultivar ‘Mary Washington
500 W’. Flower induction was most accelerated by soaking seeds in 50 mg l−1 carbamate solution for 12 days at 25 °C under the fluorescent light. Longer exposure to carbamate over a 12 day period induced a higher percentage of seedlings
to flower. A higher percentage of flowering seedlings were male. Flower induction frequency among seven cultivars through
carbamate treatment widely ranged from 13 to 67%. ‘Geynlim’, ‘Mary Washington 500 W’ and ‘Welcome’ exhibited a high percentage
of flowering seedlings, while ‘Larac’ and ‘Vulkan’ showed low values. Only male flowers were induced in all-male cultivars.
Variation in pollen germination was found within all cultivars. ‘Geynlim’, ‘Cito’ and ‘Mary Washington 500 W’ showed high
values of average pollen germination. Application of carbamate compound to induce flower production can rapidly produce homogenic
cultivars which include both sexes. This is necessary for genetic studies and breeding purposes.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
15.
Twenty two Uromyces appendiculatus isolates were tested on 20 differential and 25 Ecuadorian Phaseolus vulgaris cultivars in the seedling stage. Based on the infection types 20 races could be discerned. The Ecuadorian cultivars differed
greatly in their reaction to the isolates, from resistant to only one isolate (`Red Small Garden') to resistant to all isolates
(’G2333‘). The isolates showed a wide range of virulence to the Ecuadorian cultivars, from virulent to only two cultivars
(isolate 13) to virulent to 21 cultivars (isolates 5 and 23).
Seven cultivars with a basically susceptible infection type appeared to differ greatly in quantitative resistance when tested
in three consecutive crop cycles. The disease severities in percentage leaf area affected averaged over the three cycles ranged
between 83.9% for ‘Red Small Garden’ and 13.1% for ‘INIAP-414’.
Race-specific resistance does not seem an advisable breeding strategy, but the quantitative resistance offers a good alternative. 相似文献
16.
T. T. Efremova O. I. Maystrenko V. S. Arbuzova L. I. Laikova G. M. Panina O. M. Popova O. V. Berezova 《Euphytica》2006,151(2):145-153
Ear emergence time and response to vernalization were investigated in 12 alien substitution lines in which a pair of chromosomes 5A of recipient spring wheat cultivars was replaced by a pair of chromosomes 5R of Siberian spring rye ‘Onokhoiskaya’. The recipients were 12 spring cultivars of common wheat, each carrying different Vrn genes. Spring rye ‘Onokhoiskaya’ had the Sp1 (now called Vrn-R1) gene for spring growth habit located on chromosome 5R, but its expression was weaker. The Vrn-R1 gene had no effect on growth habit, ear emergence time and response to vernalization in wheat-rye substitution lines. Ears emerged significantly later in the 5R(5A) alien substitution lines than in the recipient wheat cultivars with the Vrn-A1/Vrn-B1/vrn-D1 or Vrn-A1/vrn-B1/Vrn-D1 genotypes. No difference in ear emergence time was found between most of the 5R(5A) alien substitution lines and the cultivars carrying the recessive vrn-A1 gene. The presence of the Vrn2a and Vrn2b alleles at the Vrn2 (now called Vrn-B1) locus located on wheat chromosome 5B was confirmed.The replacement of chromosome 5A by chromosome 5R in wheat cultivars ‘Rang’ and ‘Mironovskaya Krupnozernaya’, which carries the single dominant gene Vrn-A1, converted them to winter growth habit. In field studies near Novosibirsk the winter hardiness of 5R(5A) wheat–rye substitution lines of ‘Rang’ and ‘Mironovskaya Krupnozernaya’ was increased by 20–47% and 27–34%, respectively, over the recurrent parents. 相似文献
17.
Shahrokh Khanizadeh 《Euphytica》1994,77(1-2):45-49
Summary Canada imports more than 21,000 tonnes of strawberries annually, of which approximately 5,000–6,000 tonnes are frozen berries
used for processing at a cost of more than $ 10 million. These could be replaced by Canadian grown fruit if improved cultivars,
and suitable for mechanical harvesting, processing and fresh market adapted to canadian climatic conditions would be available.
For many years producers in Quebec have grown the cultivar ‘Redcoat’ (Sparkle × Valentine) released in 1957 by Agriculture
Canada, Ottawa. Redcoat is now rapidly being replaced by ‘Kent’, (`K68-58 × Raritan’) released in 1981 by Agriculture Canada,
Kentville. Despite Quebec's preeminant position in Canada as a strawberry producing region, no strawberry cultivars have ever
been bred specific for Quebec conditions. In 1982 a breeding program was initiated at Agriculture Canada St-Jean. This program
was terminated in 1986 without any material having been tested sufficiently for release. In 1987 a joint project between McGill
University and Agriculture Canada initiated to continue the breeding program and develop cultivars particularly suitable for
mechanical harvesting and processing, resistant to disease and adapted to local conditions.
Agriculture Canada, St-Jean-sur-Richelieu, Contribution No. 335/93.12.02R 相似文献
18.
The rice (Oryza sativa L.) crop in Arkansas is seeded from late March through early June each year. Farmers need new rice
cultivars that not only produce both high rough rice yields and high head rice across this range of seeding dates but do so
consistently. Thus, a seeding date study was conducted during 1994 and 1995 at Stuttgart, Arkansas, to study seeding date
effects on rough rice yield and head rice and selection for stability. Fourteen rice cultivars were seeded at five dates ranging
from late March through mid-June. Kang's yield-stability statistic was used to select cultivars for both high rough rice yields
and high head rice as well as stability for both traits. Plant stands from March seedings of each year were significantly
lower than for the later seeding dates. Maturity (days to 50 percent heading) was extended at the early seeding dates. Some
rice cultivars, such as ‘LaGrue’, had lower and more variable head rice when seeded early. In the June seeding dates each
year, ‘Kaybonnet’ produced rough rice yields that were more consistent with yields when planted at the earlier planting dates.
‘Bengal’, ‘Cypress’, ‘Kaybonnet’, and ‘Newbonnet’ were cultivars selected by Kang's stability statistic, which was targeted
to select cultivars with stable, high rough rice yields and stable, high head rice. The validity of using Kang's yield-stability
statistic for cultivar selection is also evident empirically by the adaptation and wide use of these four cultivars by southern
U.S. rice producers. These results indicate that seeding date studies and stability analyses would be useful tools for rice
breeders to identify cultivars that will be readily adapted and grown by rice producers.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
19.
Summary
Valsa canker is the most serious wood rot disease of apple in Japan. Dormant, excised twig assay in vitro was used to determine
resistance to Valsa canker. ‘Fuji’, ‘Starking Delicious’, ‘M.26 EMLA’, and ‘MM.106’ were considered to be highly susceptible,
while Malus sieboldii showed moderate resistance. Several cultivars belonging toM. prunifolia, M. baccata, andM. × domestica showed comparative resistance. The phloridzin content in the bark ofMalus species was studied in relation toValsa canker resistance. Phloridzin content ofM. sieboldii was lower than inM. × domestica. Comparatively resistant cultivars had similar or higher phloridzin content compared to susceptible cultivars. No clear correlations
were found between resistance and phloridzin contents in the bark ofMalus species. 相似文献
20.
Self and cross-incompatibility determination by means of fruit and seed set experiments or pollen tube growth observations
in the style has been frequently reported to be unclear in pear (Pyrus communis L.). Thus,in order to develop a reliable in vivo method to test pollen-pistil incompatibility in pear, pollen tube performance has been studied along the pistil following
self and cross-pollinations. Results show that, while pollen tube growth in the style may be an unclear test, ovule observation
at the microscope for the presence of pollen tube in the nucellus is a proper method to test incompatibility in this crop.
With this analysis we could identify S-alleles of ‘Williams’ (S1S2) and ‘Coscia’(S3S4), and three of the four possible S-genotypes resulting from the ‘Williams’ × ‘Coscia’ cross, as represented by ‘Butirra Precoz
Morettini’ (S1S3), ‘Santa Maria Morettini’ (S2S3)and ‘Tosca’ (S1S4). This result demonstrates that ‘Williams’ and ‘Coscia’ cultivars do not share any allele in common. We also established
two new inter-incompatibility groups in pear. Furthermore, the presence of a common allele between ‘Williams’ and ‘Agua de
Aranjuez’,and ‘Coscia’ and ‘Agua de Aranjuez’, three apparently unrelated old cultivars, may indicate a narrower genetic base
than expected for European pear. This finding together with the fact that 40% of new released cultivars have direct or indirect
parental relationship with the cultivars ‘Coscia’ and/or ‘Williams’, anticipates the possibility of new cases of cross-incompatibility
for this crop in the future. Both the method described and the determination of the S-genotypes will facilitate the characterisation
of self and cross-incompatibility relationships in this species.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献