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1.
Most fenugreek, Trigonella foenum-graecum L. suitable for western Canada exhibit an indeterminate growth habit and take about 120 days to produce a good proportion
of high quality seed. Late maturity is a major inconvenience for seed producers in temperate climates prevalent in this region
where plants must mature within a much shorter growing season. The objective of this study was to develop early maturing fenugreek
mutants with a determinate growth habit to ensure uniform maturity within the 100 frost free days available on the Canadian
prairies. Seeds from Tristar Fenugreek, a forage cultivar developed for production in western Canada, were treated with 10–300 mM
ethyl methane sulfonate (EMS) for 2–24 h and plants were selected for determinate growth habit, early maturity and high seed
yield. This mutation breeding approach has detected new breeding material exhibiting early seed maturity coupled with high
seed yield, seed quality and determinate growth habit. Successful development of useful mutants in fenugreek was reported
before, but this is the first report on successful use of mutation breeding for improvement in quantitative traits in this
crop. 相似文献
2.
Growth trials were conducted outdoors in the UK to determine the yield, yield components and plant architectural differences
between determinate and indeterminate Phaseolus vulgaris bean plants. F3 lines derived from crosses between ‘Prelude’, a determinate cultivar and ‘V8’, an indeterminate landrace,
were grown together with the parents and ‘Carioca’, an indeterminate landrace from Brazil. Data were recorded on flowering
date, number of nodes on main stem at flowering, plant height at maturity, number of pods/plant, number of seeds/pod, number
of seeds/plant, 100-seed weight, seed mass/plant, percentages of diseased and healthy seeds/plant. Determinate F3 lines had
significantly lower (P < 0.05) seed mass/plant, fewer pods/plant, fewer seeds/pod, fewer seeds/plant, lower harvest index, shorter stems, earlier
date of flowering, fewer nodes at flowering and fewer healthy seeds/plant than indeterminate F3 lines. However, determinate
genotypes had significantly larger (P < 0.05) pods to accommodate their larger seeds compared with indeterminate lines. A similar situation was found when the
yield and yield components of ‘V8’, ‘Prelude’ and ‘Carioca’ were evaluated; the highest seed mass/plant was given by ‘V8’
and the lowest by ‘Prelude’. Furthermore, some indeterminate genotypes with Type IV growth habit yielded significantly higher
(P < 0.05) than the high-yielding parent, ‘V8’, indicating a positive influence on seed yield by crossing different genotypes. 相似文献
3.
In order to investigate the agricultural potential of the genus Vicia, and identify traits associated with productivity and responsiveness to environment, 34 undomesticated Mediterranean accessions
representing Section Narbonensis (V. johannis, V. narbonensis) and V. sativa were grown in five contrasting environments in northern Syria (growing season rainfall: 76–290 mm).Highly significant genotype
× environment interactions were observed for all traits. For most of the components of yield, accession mean performance (productivity)was
highly correlated with responsiveness across environments (r = 0.59–0.96), as defined by joint linear regressions. Thus high yielding genotypes tended to be relatively more productive
than low yielding genotypes under conditions that favoured high yields. Regression analysis revealed that mean site yields
were positively correlated to rainfall (r = 0.85) and its attendant effect on growing season length as measured by cumulative season temperature and phenology (r = 0.59–0.81).In order to examine yield related traits independently of taxonomy, genotypes were grouped into three categories
using K-means clustering based on productivity and responsiveness of seed, hay and biological yield. Highly productive/responsive
genotypes were tall with high harvest index, large seeds and low fecundity (seeds and pods per plant), whereas unproductive/unresponsive
plants tended to be short, highly fecund, with small seeds and low harvest index. Principal components analysis showed that
responsiveness, in terms of seed, hay and biological yields, was closely related to phenological plasticity. Thus highly productive/responsive
genotypes were able to start flowering earlier than unproductive/unresponsive genotypes in early environments, but significantly
later in late, higher rainfall environments. Plant growth habit was also related to yield responsiveness. In environments
with little biomass production the proportion of erect plants was high in all three categories. In more favourable, high biomass
environments, the proportion of erect plants in unproductive/unresponsive genotypes fell dramatically, but was unchanged among
productive/responsive genotypes. We suggest that for unproductive/unresponsive genotypes competition for light is increased
under optimal growth conditions. We argue that the optimal combination of fixed and responsive traits in high yielding genotypes
results in a `compound interest-type' response to more favourable environments. Highly productive and responsive genotypes
can capture resources more effectively than their low yielding counterparts, leading to a positive relationship between performance
and responsiveness for most components of yield. Differences in productivity and responsiveness for seed, hay and biological
yield reflected Vicia taxonomy, increasing in the following order from low to high: V. johannis, V. sativa, the small seeded V. narbonensis (salmonea, jordanica, affinis) V. n. var. narbonensis, and finally V. n. var.aegyptiaca. V. n. var. aegyptiaca showed the most agricultural potential, since the taxon contained all the properties of productive/responsive genotypes listed
above, yielding >1 t/ha under extremely arid conditions (104 mm),and >2.5 t/ha on 290 mm rainfall, confirming its potential
for dry environments.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
4.
Breeding barriers between the cultivated strawberry, Fragaria × ananassa, and related wild germplasm 总被引：1，自引：0，他引：1
Arias E. Marta Elsa L. Camadro Juan C. Díaz-Ricci Atilio P. Castagnaro 《Euphytica》2004,136(2):139-150
Five-hundred interspecific and intergeneric crosses were performed among accessions of the wild strawberries Fragaria vesca(2x), Duchesnea indica (8x), Potentilla tucumanensis (2x) and 9 genotypes of the cultivated strawberry, Fragaria×ananassa (8x), following an incomplete diallele mating design. Crosses between D. indica and F.×ananassa produced many putative hybrids when D. indica was used as female but a few achenes and plants when used as male; therefore, pollen-pistil compatibility relations were
analyzed by fluorescence microscopy in this direction of the cross. Of the genotypic combinations, 78.6% were incompatible
at the stigma level and 17.2% at the first third of the style. Only 3.6% were pollen-pistil compatible and produced fruits
with achenes (seven did not germinate or originated short-lived plants and nine produced normal plants). F.vesca×F.×ananassa crosses produced 35 hybrid achenes but only 14% germinated, yielding short-lived plants; histological analyses revealed that
inviable seeds had less developed (or collapsed) endosperms and smaller embryos than control plump F. vesca seeds. P.tucumanensis was only used as male, with negative results. These species and genera are partially isolated by a complex system of pre-
and post-zygotic barriers. Knowledge of their nature would allow the breeder to devise strategies to put the genetic variability
available in the group into a useful form.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
5.
Summary The occurrence of seed malformation in association with reduced thousand grain weight and germination ability has been observed in crosses between cultivated female plants and wild male plants. A survey of 16 cultivated accessions (P. glaucum subsp. glaucum) and 11 wild accessions (P. glaucum subsp. monodii) ranging over the whole species diversity showed this postzygotic incompatibility was general, but its intensity varied greatly with the cultivated female accession used and very little with the wild male parent origin. About 15% of the 123 cultivated x wild crosses observed gave normal seeds. Seed malformation has never been observed in crosses between cultivated accessions and appeared independent of genetic distances between the parents. The reciprocal crosses between wild female plants and cultivated male plants gave normal-looking seeds with good germination but consistently reduced thousand grain weight. Both seed malformation and seed small size are an expression of a genetic imbalance. These slight reproductive barriers seem to have been built during the domestication process.Abbreviation ICRISAT
International Crop Research Institute for the Semi-Arid Tropics 相似文献
6.
Summary The South American wild potato species Solanum commersonii Dun. exists as two subspecies, subsp. commersonii and subsp. malmeanum (Bitter) Hawkes and Hjerting, and as both diploid and triploid cytotypes. The two subspecies were completely cross fertile but there were reciprocal differences in the number of seeds set per berry and the mean seed weight. Crosses between diploids and colchicine-induced autotetraploids yielded only a few seeds per berry, but 16 of the 18 germinated seeds were triploid or nearly so. Such a high proportion of triploids is unusual for such crosses in potatoes. Some triploids has a high percentage of stainable pollen. The origin of naturally occurring triploids is discussed in the context of 2n gametes, a triploid block, and endosperm balance numbers. 相似文献
7.
Summary Crosses of wild barley (Hordeum vulgare ssp. spontaneum and Hordeum vulgare ssp. agriocrithon) with Hordeum vulgare ssp. vulgare were used to select high yielding grain types under dryland Mediterranean conditions. No special difficulties were faced in making the crosses, in eliminating the brittle rachis genes from the grain types or in selecting 6-rowed types in crosses between 2-rowed wild barley and 6-rowed ssp. vulgare varieties. Brittle rachis genotypes, present in the segregating populations were used in developing self-reseeding permanent pastures for dry areas. The best selections were tested in seven trials during 1989–92 and some of them outyielded their parents and also the best improved check variety by 13–22%. Indications for transgressive segregation were obtained for grain yield, straw yield, total biological yield, harvest index and volume weight. The crude protein content of some of the selections was significantly higher than that of the checks. For breeding programs aiming at large seeds, special ssp. spontaneum lines should be used as parents. High grain yield was positively correlated with high straw yield, total biological yield, earliness in heading date, high harvest index and negatively with volume weight. It was concluded that unexploited useful genes, even when not directly observed in wild barley, could be transfered easily into high yielding genotypes by breeding. 相似文献
8.
Summary Physiological and morphological characteristics of the two wild and three domesticated subspecies of cowpeas are compared. The wild accessions are alike in having small, hard seeds borne in dehiscent pods, but differ in other characteristics. We suggest that the wild subsp. dekindtiana, from the seasonally-arid tropics, is more likely to have been the progenitor of modern cowpeas than the other wild subspecies (subsp. mensensis), but that subsp. dekindtiana was first cultivated in the humid tropics where its pods are slow to dehisce. Domestication has been associated with changes in the structure of pod valves and seed coats which reduce pod dehiscence and seed hardness. Pods and seeds have increased in size, mainly by increases in the rate of dry weight accumulation, and their increase has been only partly paralleled by increase in the area of subtending leaves. There has been no increase in the maximum photosynthetic rate of leaves, but the duration of their photosynthetic activity has increased. Domesticates are less sensitive than are wild plants to some environmental controls, such as in the response of germination to temperature, but in their flowering responses to daylength both wild and cultivated forms retain sensitivity under conditions where this is of adaptive value. 相似文献
9.
Zahra Bitarafan Fulai Liu Christian Andreasen 《Journal of Agronomy and Crop Science》2020,206(2):169-175
In two identical pot trials, we investigated the effect of different biochars on the growth and water use efficiency (WUE) of fenugreek (Trigonella foenum-graecum L.) grown with and without water stress. Plants were grown in pots with and without biochar. Rice husk (RH), standard rice husk (SRH), standard wheat straw (SWS) or standard oilseed rape straw (SOS) biochars were added at a rate of 2% by weight. Irrigation was reduced from 80% of field capacity to 40% in half of the pots to create water stress when 50% of the plants flowered. No significant interaction was observed between irrigation and biochar treatments. Water stress resulted in smaller plants (11.5%), fewer pods (16.1%) and reduced 100-seed weight (12.6%), seed yield (20.1%) and plant dry weight (55.0%). All standard biochars increased plant dry weight in a range of 18%−25% compared with the controls. There was no significant effect of biochar on the number of pods and seed weight. Only RH, SWS and SOS biochar increased the number of seeds pod−1 by 9.0%−14.5% compared with the controls regardless of water stress. RH and SOS biochars increased seed yield by 16.7 and 21.6%, respectively. RH, SWS and SOS biochar increased the WUE by 17.3%, 10.1% and 16.2% regardless of water stress, respectively. Based on the experiment, we recommend farmers to add biochar whatever type they have available. However, RH and SOS seem to be better than the others are, as they seem to be able to increase seed yield and WUE considerably. 相似文献
10.
M. O. Akoroda 《Euphytica》1990,49(1):25-32
Summary Studies during 1980–1987 relating to seed production of the fluted pumpkin (Telfairia occidentalis Hook. f.) are summarized. Essentially, the dioecious nature of the crop makes sex-ratios of plants affect the number of fruit-bearing females. Overall, about 50% of plants are female, of which some 15% are fruitless. Each fruit-bearing female has 1.5 fruits that contain 60 seeds. The mean weight of seeds is 15 g, and 74% of this total seed weight comprise the seed kernel which contains about 40% oil. Thus, a yield estimate of seed kernels reaches 1.9 t/ha; an output that is superior to that of most other oil seeds now being exploited for seed oil and cake in Nigeria. Measures to raise seed yields and the possibility of breeding work are discussed. 相似文献
11.
Summary InDactylis glomerata L. subsp.lusitanica, triploid and tetraploid plants were obtained by bilateral sexual polyploidization in crosses between diploid parents known to produce 2n gametes. The polyploid and diploid progeny were compared for allozyme diversity (allele number and heterozygosity), phenological (pollen fertility, inflorescence emergence date), cellular (stomatic cell size) and morphological characters (vegetative biomass, seed weight, total seed number per plant, panicle number and seed number per panicle length) in four contrasting growing conditions. Stomatal cell size and the total number of alleles were significantly lower in diploids than in polyploids which sometimes recovered more than two distinct alleles at a locus via 2n gametes possessing heterozygous loci. Pollen fertility was similar in diploids and tetraploids, but significantly lower in the triploids. Seed weight was significantly higher in polyploids, although the average number of seeds per panicle length and the total number of seeds was higher in the diploid sibs. No phenological differences occurred among ploidy levels whereas such differences were observed inDactylis in all the natural areas of sympatry between diploids and their related polyploids. Our results provide evidence for an instantaneous effect of polyploidization on certain traits and suggest that natural selection would act subsequently on several other traits to allow the establishment of new polyploids. 相似文献
12.
This paper describes the relative efficiency of three marker systems, RAPD, ISSR, and AFLP, in terms of fingerprinting 14
rice genotypes consisting of seven temperatejaponica rice cultivars, three indica near-isogenic lines, three indica introgression lines, and one breeding line of japonica type adapted to high-altitude areas of the tropics with cold tolerance genes. Fourteen RAPD, 21 ISSR, and 8 AFLP primers
could produce 970 loci, with the highest average number of loci (92.5) generated by AFLP. Although polymorphic bands in the
genotypes were detected by all marker assays, the AFLP assay discriminated the genotypes effectively with a robust discriminating
power (0.99), followed by ISSR (0.76) and RAPD (0.61). While significant polymorphism was detected among the genotypes of
japonica and indica through analysis of molecular variance (AMOVA), relatively low polymorphism was detected within the genotypes of japonica rice cultivars. The correlation coefficients of similarity were significant for the three marker systems used, but only the
AFLP assay effectively differentiated all tested rice lines. Fingerprinting of backcross-derived resistant progenies using
ISSR and AFLP markers easily detected progenies having a maximum rate of recovery for the recurrent parent genome and suggested
that our fingerprinting approach adopting the ‘undefined-element-amplifying’ DNA marker system is suitable for incorporating
useful alleles from the indica donor genome into the genome of temperate japonica rice cultivars with the least impact of deleterious linkage drag. 相似文献
13.
B. Maris 《Euphytica》1986,35(2):465-482
Summary Fifty-five populations from crosses of three Solanum tuberosum ssp. tuberosum cultivars and seven selected S. tuberosum ssp. andigena clones adapted to the northern temperate zone have been studied in the seedling and the first and second clonal generation. This paper only deals with the effect of seed tuber weight on various important agronomic characters which are selected for in early clonal generations, independently of the type of crosses.The results showed that a distinction has to be made between the effects of differences in seed tuber weight within and between seedlings, i.e. genotypes. The effects on the first clonal generation of differences in weight of the tubers within seedlings and those of the first heaviest tubers between seedlings were similar and comparable to seed tuber weight effects within cultivars. In contrast to the within seedlings effects the between seedlings effects proved to be heritable. This is concluded from the fact that, on average, independent of seed tuber weight seedlings with larger first heaviest tubers performed better in the second clonal generation than those with smaller ones. Notably plant height, general impression, date of maturity and particularly tuber yield and mean tuber weight in the second clonal generation were related to the weight of the first heaviest tubers of the seedlings. The potentialities of these findings for an early generation selection are discussed. 相似文献
14.
Pollination with gamma-irradiated pollen and development of fruits,seeds and parthenogenetic plants in apple 总被引：3，自引：0，他引：3
Summary Four apple (Malus X domestica) genotypes, Erovan, Golden Delicious, R1-49 and X6677, were pollinated with a marked pollen irradiated by -rays at doses ranging from 125 to 1000 Gy. Pollination with such irradiated pollen affected fruit set, seed number and seed contents, and induced the formation of parthenocarpic fruits and the development of parthenogenetic embryos. The immature embryos extracted from seeds. 2 and 3 months after pollination, were cultured in vitro and germinated after 2 months of cold treatment (3°C). Haploid plants were obtained in all 4 genotypes, after pollination with pollen irradiated at doses from 200 to 500 Gy. The optimum conditions for induction of apple haploids, by irradiated pollen approach, have been established. 相似文献
15.
Summary Callus induction and green plant regeneration at high frequencies from an interspefic hybrid, Oryza sativa L. x O. rufipogon Griff. has been achieved by simply coordinating the growth regulators in the induction medium. The study was conducted with two different basal media (Potato-2 and N6) and seven different combinations of growth regulators 2,4-D, NAA and kinetin. Synergistic effects of the two auxins in enhanced anther response to callus induction and subsequent green plant regeneration were observed in both media. The highest frequency of callus induction was obtained on Potato-2 medium supplemented with 1 mg/12,4-D, 2 mg/l NAA and 1 mg/l kinetin. The same combination of growth regulators which yielded higher frequencies of callus induction also induced higher mean number of calli per anther. Although the calli formed on N6 medium showed high regenerability, there was a concomitant increase in the number of albinos among the regenerants. The auxins in the induction media had considerable influence on the regeneration capacity of the calli. The regeneration frequencies were higher from calli formed in the presence of both auxins in the induction media. The levels of growth regulator combinations seem to influence the green plant regeneration especially for calli induced on Potato-2 medium. Among the pollen grain derived plants the majority were either haploids or double haploids and very few were chromosomal variants. 相似文献
16.
Combining ability of seed vigor and seed yield in soybean 总被引：4，自引：0，他引：4
Studies have shown no consensus in relationships between seed yield and vigor in soybean [Glycine max (L.) Merrill]. The lack of information regarding the inheritance of seed vigor prompted this study to determine the types
of gene action and combining ability estimates for seed vigor and its related traits. Five high and six low seed vigor soybean
genotypes were crossed in a diallel, and selfed to produce 55 F2 progenies, which were examined, along with the parents, for seed vigor, yield, and seed weight. Significant genotype and
environment effects were found for seed vigor and yield. General combining ability (GCA) effects for seed vigor and seed yield
were significant (p≤ 0.01) and larger than specific combining ability (SCA) effects. Significant GCA and SCA effects were found for seed weight,
indicating that both additive and non additive genetic effects were involved in conditioning seed weight. The ratios of mean
square, 2GCA / (2GCA+SCA), were 0.96 for seed vigor and 0.93 for seed yield. These ratios indicated that additive gene effects
were more important than non additive gene effects for seed vigor and seed yield in these crosses. Mean seed vigor(83.8%),
as determined by accelerated aging germination, and mean seed yield (2,155 kg ha-1)in high vigor × high vigor crosses were higher than the high vigor × low vigor and low vigor × low vigor crosses. Mean percent
accelerated aging germination rates in F2 populations from diallel crosses were significantly related to mid-parent seed vigor(r2 = 0.52**) and midparent seed size (r2 = 0.31**). These results indicated that levels of seed vigor can be improved through breeding, while maintaining high yields because
of the predominance of GCA effects in both seed vigor and seed yield.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
17.
Summary The efficiency of indirect selection for seed yield was compared with direct selection for yield per se in chickpea. A total of 2500 single F2 plants, derived from 50 crosses with 50 plants from each cross, were divided into five sub-populations (SP1 to SP5) of 500 plants each by including 10 plants from each of the 50 crosses. The five sub-populations were advanced upto F6 by exercising 10% selection intensity for four successive generations for number of pods per plant in SP1, number of seeds per pod in SP2, seed weight in SP3, seed yield in SP4 and random selection in SP5. The efficiency of direct and indirect selection for yield was evaluated by comparing groups of 50 F6 lines from each sub-population. SP1 and SP3 F6 lines showed higher mean grain yield than the other three methods. SP1 and SP3 were found to be almost equally efficient in developing F6 lines which were significantly superior to the check. This suggests that indirect selection for yield via pod number and seed weight is more efficient than direct selection for yield. 相似文献
18.
Summary Ninety Chinese rice landraces were examined with special reference to the indica-japonica differentiation in terms of traditional criteria, isozyme analysis and PCR analysis of the chloroplast DNA (cpDNA). Cultivars were separated into indica and japonica defined by a discriminant function (Z) based on key characters, as well as by isozyme genotypes. Most indica landraces had chloroplast DNAs with a deletion at the Pst-12 fragment, while most japonica landraces had cpDNAs without the deletion. Two traditionally recognized varietal groups in China, keng and hsien, corresponded largely to the respective japonica and indica revealed in our study. The results obtained in this study showed good agreement for classification of indica and japonica types by the three methods: discriminant analysis by Z value, isozyme analysis, and PCR analysis for cpDNA. 相似文献
19.
A.H. Marshall T.P.T. Michaelson-Yeates M.T. Abberton A. Williams H.G. Powell 《Euphytica》2002,126(2):195-201
Interspecific hybridisation with Trifolium nigrescens Viv. is a possible strategy to improve the reproductive potential of white clover (Trifolium repens L.). Following the development of a fertile F1 hybrid, three generations of backcrossing have been carried out usingT. repens as the recurrent parent. Vegetative characteristics, stolon growth and seed yield components of the backcross (BC) 2 and
3 generations, as well as the parental species were measured on spaced plants grown in the field. Leaf size and plant spread
of the BC2 and BC3 generations were less than T. repens but there was no difference in plant fresh weight. Numbers of inflorescences per plant and florets per inflorescence of the
backcrosses were greater than T. repens however this was not reflected indifferences in seed yield per plant asT. repens had more seeds per floret and per plant than the backcrosses. Differences in stolon length, the proportion of flowering nodes
and the pattern of axillary bud development were observed between T. repens and the backcrosses. Significant variation among the BC 3 generation for vegetative and reproductive traits was observed.
Individual plants among the BC 3 generation were identified that combine high forage yield, substantial inflorescence production
and good fertility, and these will form the basis of further selection.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
20.
The combining abilities for physical-quality traits in peanut were examined to understand the type of gene action governing
these traits, and to identify peanut genotypes suitable for use as parents in breeding for quality improvement. The F1 hybrids including reciprocals from a six-parent diallel cross along with the parents were evaluated in a randomised complete
block design. Data were recorded on five quality traits in peanut viz., shelling outturn, 100-pod weight, 100-seed weight, Count and proportion of sound mature seeds. Substantial genetic variability
was observed among the hybrids for the traits studied. Diallel analysis indicated that expression of majority of the quality
traits is regulated predominantly by additive gene action suggesting possibility of early-generation selection, while non-additive
gene action also plays an equally important role in the control of seed size. Significant reciprocal effect for all the traits
denoted role of maternal parent in the expression of quality traits and importance of parental selection in quality breeding.
Genotypes ICGV 86564 and TPG 41 were good combiners for seed size, while J 11 was a good combiner for improvement of shelling
outturn and proportion of mature seeds. Association between general combining ability (GCA) effects and mean performance suggested
that the performance per se of the genotype should be a good indicator of its ability to transmit the desirable quality attributes
to its progenies. Though performance of crosses was found to be independent of parental GCA status, it is evident that at
least one of the parents used in hybridisation should have large pods and seeds for obtaining better segregants. 相似文献