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1.
Summary Self-, cross-, and open-pollination(OP)-fertility relationships were examined on the basis of seeds per panicle for two years. A fertility index was employed as a relative measure of self-fertility. The correlation between self-fertility and cross-fertility was positive and significant for both years. The association between self-fertility and OP-fertility was not significant in 1969 but significant in 1970 and over both years combined. Cross-fertility exhibited a significant and positive correlation with OP-fertility in 1969 but not in 1970. Inter-annual correlations for self-fertility, cross-fertility and OP-fertility in 1969 and 1970 were all positive and significant. The analysis of variance of self-pollination seed-set indicated highly significant differences for self-compatibility among clones for both years. Germinability of seed-set after self-pollination was lower than that of the cross- or open-pollinated seeds. General combining ability was more important than specific combining ability for cross-fertility in both years. However, specific combining ability appeared more important than other components for germinability of the diallel cross seeds.Research supported by the College of Agricultural and Life Sciences, University of Wisconsin, Madison, Wisconsin 53706, USA. 相似文献
2.
The self-fertility of chromosome-doubled haploid lines of perennial ryegrass and their first (I1) and second (I2) generation selfed offspring was studied. The overall seed set was low, 0—0.4 seeds per spike, as would be expected for chromosome-doubled haploids of a self-incompatible species. Nevertheless, significant genetic variation was observed for self-fertility within three of the six lines studied. Within one line, three I2-clones showed increased self-fertility, while in two other lines one and three I1-clones, respectively, showed significantly increased self-fertility. Selection, during selfing, of rare pollen grains with mutations in the self-incompatibility system could explain the observed changes and would lead to a general breakdown of self-incompatibility in Lolium perenne during repeated selfing of chromosome-doubled haploids. 相似文献
3.
不同基因型不同播期玉米单倍体自然加倍效果的研究 总被引：5，自引：1，他引：4
摘要：本文研究了不同基因型不同播期玉米单倍体的自然加倍效果。结果表明：不同基因型单倍体自然散粉率差异很大;单倍体的自然散粉率为6.56%～65.33%;夏播自然散粉率比春播高3.77%,自交结实率为6.23%～9.39%,单倍体自交结实率夏播比春播高2.37%;夏播有利于单倍体自然散粉及自交结实。 相似文献
4.
枣不同品种开花结实及花粉发芽特性研究 总被引：4，自引：1，他引：4
对枣22个品种开花类型,12个品种的花粉发芽率,5个品种的花粉萌发动态,9个品种的花粉贮藏和10个品种自花结实率进行了研究。结果表明,脆枣、辣椒枣、葫芦枣、福枣、扁核酸、骏枣、赞皇大枣、红颜、无等、稷山圆枣、晋枣、绵枣、尖枣、临猗梨枣、长红、酥枣是昼开型;湖南鸡蛋枣、冬枣、束鹿糖枣、月出、尖头灰、屯屯枣是夜开型。其中脆枣、辣椒枣、葫芦枣、福枣、骏枣、赞皇大枣、红颜、无等、稷山圆枣、晋枣、绵枣、尖枣、酥枣、湖南鸡蛋枣、束鹿糖枣、月出、尖头灰、屯屯枣皆为首次报道。供试枣品种间花粉发芽率有很大差异,为1.52%~74.95%,平均发芽率为34.28%,变异系数为14.74%,其中冬枣最低,辣椒枣最高;花粉在散射光下培养与黑暗条件下培养对花粉发芽率没有显著差异。花粉-12℃干燥器贮藏极显著地好于2℃干燥器贮藏和室温干燥器贮藏;-12℃干燥器贮藏条件下,贮藏6d、10d的花粉发芽率分别是新鲜花粉的88.04%、59.88%。花粉发芽动态试验表明,花粉发芽率和花粉管生长曲线呈单S型,培养5.5h花粉发芽率不再变化,7.5h花粉管停止生长。供试枣品种的自花结实坐果率几乎为零。 相似文献
5.
A mutation causing self-fertility (SF) in perennial ryegrass was studied at the tetraploid level. The aim of this work was to determine a) whether SF remains functional in a tetraploid population and b) whether the SF mutation expresses dominance in heterozygous pollen grains. A tetraploidized plant carrying SF alleles was self-pollinated to create a segregating F2 population. In the F2 individuals, pollen compatibility ranged between 38% and 84% showing that SF remained functional. The SF locus genotype was the main determinant of pollen compatibility explaining 78% of the variation. The observed segregation was significantly different from the expected under both SF being dominant or recessive models (P(χ2)≤0.001) and tended to be intermediate between them, indicating partial dominance or additive gene action. The frequency of the different genotypes suggested that pollen grains homozygous for the mutation have a competitive advantage over heterozygous pollen and that pollen compatibility is affected by the interaction with additional loci. The implications of our results for breeding polyploid grasses are discussed. 相似文献
6.
不同果袋对大五星枇杷果实品质影响 总被引：1，自引：0，他引：1
为了提高枇杷产量,生产精品枇杷,于2013年4-5月在贵州省余庆县进行了枇杷不同果袋套襞试验.试验结果表明：枇杷大五星品种果实套袋后果实橙黄色、茸毛多、果锈少,未套袋（CK）的果实橙红色、茸毛少、果锈多,果袋外黄内白、外黄内黑、外黄内黄的平均单果重与未套袋（CK）的平均单果重43.00 g相比,分别增加11.54 g、11.19g、7.22g,耒套袋的日灼率11.50％、鸟食率9.5％、裂果率11.2％、农药残留抑制率1.60％,套袋处理的日灼率0、鸟食率0、裂果率1.9％～2.2％、农药残留抑制率0.枇杷采用套袋技术,可提高果实品质,防止日灼和鸟害,降低裂果率,减少果实农药残留和大气污染.综合各因素分析,建议在贵州省枇杷种植区推广应用外黄内白或外黄内黑的双层果袋套袋. 相似文献
7.
Anna Iannucci 《Euphytica》2004,136(2):103-113
The selfing effect in berseem clover (Trifolium alexandrinum L.) was analysed by comparing generation means for nine agronomic traits (dry matter yield, plant height, leaf-stem ratio,
harvest index, seed yield and its components). Parents, S1, S2, S3, and S4 generations of six populations of different geographical origin (3 from Egypt and 3 from southern Italy) were investigated
to estimate the relative changes with increasing homozygosity and to prove the effectiveness of selfing in a breeding program.
The experiment was carried out at Foggia (Italy) under field conditions for two years (1995 and 1996) adopting two cutting
treatments: at fifth internode elongation (A) and flowering (B). The mean values decreased with the advancement in selfing
generations in both years and cutting treatments for the most of the traits. Treatment B yielded more biomass and seed yield
than treatment A in both years. Cutting treatments did not affect the adaptability of the selfed progenies of populations
with different geographical origin, in fact, the Italian populations were more productive for dry matter under both cutting
treatments (856.6 g m-2 on average), whereas Egyptian populations proved superior for seed yield particularly under treatment B (62.5 g m-2 on average). Inbreeding depression was greater for forage dry matter and seed yield (−62and −79% on average, respectively),
whereas the plant height and 1000-seed weight were the least susceptible traits (−26 and −19% on average, respectively). Estimates
of the parameters of the stability analysis showed that not all populations responded to inbreeding level and environment
variations to the same degree. Differences were evident under treatment A, only. Development of self-fertile, relatively vigorous
inbred lines of berseem clover with different degrees of homozygosity appears possible. Genotypes tolerant to selfing from
Egyptian and Italian groups have been obtained by inbreeding and selection for self-fertility; they could be utilised as basis
for producing new breeding activities.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
8.
A. H. Eenink 《Euphytica》1984,33(1):161-167
Summary After double or triple pollinations including selfing and the use of one-day-old compatible foreign pollen a severely self-incompatible clone could be forced to develop a reasonable amount of self-seeds per flower head. This number of self-seeds increased when the foreign pollination was delayed for e.g. 240 minutes in the double pollination experiment. Even more self seeds were obtained in the triple pollination experiment with a delayed second selfing.The influence of the old foreign pollen may be caused by a mentor pollen or a pioneer pollen effect. 相似文献
9.
The Response of Anther Culture in a Genetically Wide Material of Winter Wheat (Triticum aestivum L.) 总被引：1，自引：0，他引：1
In a screening experiment with 215 different winter cultivars of Triticum aestivum L. for response in anther culture, pollen embryos or callus were obtained from 200 different cultivars and green plants from 93 different cultivars. On average, from the whole material, 1.3 green plants were obtained per 100 anthers cultured. Variance components estimated from replicates with selected parts of the plant material indicated that for the formation of pollen embryos from anthers, interactions between genotypes and replications were dominating, accounting for 45 to 50 per cent of the variation. Main effects from genotypes were less prominent, accounting for 25 to 30 per cent of the variation, and the replications showed relatively little effect, accounting, for about 4 to 12 per cent of total variation. Regeneration of plants from pollen embryos or callus was not significantly influenced by either genotype or replicates. The frequencies of plants regenerated being green, however, were influenced from both genotype and environments contributing 42.5 and 34.9 per cent of the total variation respectively, while only minor interactions between genotype and environments were indicated for this character. 相似文献
10.
Inbred lines of white clover (Trifolium repens L.) have been produced utilising the rare self-fertility (Sf) allele. Twenty-two
lines of four distinct groups have been maintained through five generations of selfing by single seed descent. Fourteen lines
were used in crosses to produce F1s. Both parents and hybrids were analysed for a range of morphological characters. Positive heterosis for dry matter production
was observed in half the hybrids. No other trait showed significant heterosis. The degree of heterosis appears to be related
to the extent of variation in morphological characters between the parental lines, some combinations of lines yielding heterotic
hybrids in all cases, others in none. The majority of the F1 hybrids are superior in terms of dry matter production to eight control varieties.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
11.
采用中SNP160K芯片对丰收24×通交83-611 F2群体252个植株及其亲本进行基因分型,构建了一张由5861个SNP标记组成的全长为3661.46 cM的高密度遗传连锁图谱。利用完备区间作图法(ICIM)定位到7个株高QTL,每个QTL可解释2.56%～10.41%的株高变异。qPH-6-1具有最高的表型变异贡献率和显性效应,可解释10.41%的株高变异,加性效应和显性效应分别为–1.72和18.94; qPH-18-1贡献率次之,可解释9.64%的株高变异,但具有最高的加性效应,达-12.42。在F2群体中筛选出11个qPH-6-1和qPH-18-1基因型为Q6Q6/Q18Q18的单株,平均株高167.00 cm;筛选出16个基因型为q6q6/q18q18的植株,平均株高为91.25 cm。在qPH-18-1定位区间内外增加23个SNP标记,将定位区间由766.97kb缩小至66.03kb,包含8个基因,结合基因注释和相对表达量差异分析,推测Glyma.18G279800和Glyma.18G280200可能与大豆的株高相关。本研究为大豆株型的改良提供了分子参考依据和遗传基础。 相似文献
12.
M. Leflon A. Hüsken C. Njontie S. Kightley D. Pendergrast J. Pierre M. Renard X. Pinochet 《Plant Breeding》2010,129(1):13-18
At the field scale, the co-existence of different farming production systems requires strategies to prevent gene flow between adjacent crops. Oilseed rape produces pollen dispersed by wind and insects and the risks of pollen mediated gene flow are significant for this crop. Cleistogamy, the trait of non-opening flowers, could be used to reduce pollen flow. Cleistogamous oilseed rape genotypes were obtained by INRA in France and were bred in order to improve the stability of this trait. In this paper, we examine the reliability of the cleistogamous trait for two inbred lines. The flower opening level was measured at different dates during the flowering period in six field experiments (three sites × 2 years). The results showed that some flowers were partially opened with rates varying from 0.5% to 33% principally depending on genotypes, trials (site and year) and recording dates. Given that other studies have shown that cleistogamy could reduce pollen dispersal, we consider that, even when partially unstable, cleistogamy could be beneficially used in combination with other means in a containment strategy. 相似文献
13.
Fitness in tall fescue could be determined as the relative seed production by overcoming self-incompatibility barriers. This study was an attempt to investigate the effects of plant genotype and symbiotic fungal endophyte on seed production and associated traits in tall fescue. Fifteen clones of tall fescue free from endophyte and two clones with both endophyte-infected (E+) and non-infected (E?) counterparts were evaluated under two pollination systems of natural open-pollination and obligate self-pollination. Although seed yield was depressed by self-pollination in all E? genotypes, some genotypes exhibited reasonable selfing ratio. However, endophyte infection was much more effective to increase selfing ratio and seed yield through self-pollination particularly in the genotype 75B. Endophyte infection almost removed self-incompatibilty in the host plants and on average resulted in 3.0 times more number of seeds per self-pollinated seedheads than the non-counterpart E? tall fescue genotypes. Although it may need more elaborated studies, incorporating Epichloë fungal endophyte in plant genotypes not only may make the inbreeding in tall fescue possible but also may improve forage yield and seed production, simultaneously. 相似文献
14.
Summary Our objective was to determine the average numbers of pollen grains from fertile plants (Ms
1) and the average numbers of coenocytic microspores from genetic male sterile plants (ms
1
ms
1) in soybeans, Glycine max L. Merr. Comparisons were made between the average numbers of pollen grains and the average numbers of coenocytic microspores with respect to environment where plants were grown and to stamen position in the flower. Five male sterile lines were used. They included the North Carolina ms
1 mutant, the cultivar Hark with the ms
1 gene, and mutants identified as the Urbana, Tonica, and Ames male steriles. Three environments used were the Agronomy Farm, University of Georgia, Athens, Georgia; the Agronomy and Agricultural Engineering Research Center, Iowa State University, Ames, Iowa; and the Agronomy Greenhouse, Iowa State University, Ames, Iowa.Pollen production from fertile plants varied from 374 to 760 pollen grains per anther among genetic lines and environments. This variation may be an important consideration in selecting a male parent to use as a pollinator for hybrid seed production.Among fertile plants, the average numbers of pollen grains per anther of the separate stamen and and of the lower whorl of stamens were significantly different only in greenhouse-grown plants. Among male sterile plants, the average numbers of coenocytic microspores per anther of the separate stamen and of the lower whorl of stamens were significantly different in three genotype x environment combinations. These three exceptions did not conform to any genetic or environmental pattern. Deviations from the expected ratio of 4 pollen grains from fertile plants: 1 coenocytic microspore from sterile plants were attributed to initial differences in the average number of microspore mother cells between the two genotypes.Joint contribution: Agricultural Research Service, USDA, North Central Region, and Journal Paper No. J-8910 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa 50011; Project 2107. 相似文献
15.
Summary Maintaining maize (Zea mays L.) inbred lines without genetic change is an important concern of maize breeders and seed producers. Long-time inbred lines, however, have been shown to be genetically unstable, and with selection pressure acting on the resulting genetic variation, these lines have evolved into different strains. The objective of this study was to compare maintenance of line integrity under reproduction by sib-mating and self-pollination in ear-to-row progenies. Ten lines, varying from 5 to 35 generations of previous ear-to-row selfing, were maintained for 11 successive generations under each method of reproduction. Alternate generations were compared by using a randomized complete-block design with each family of lines as a separate experiment. Data were collected for 10 plant and yield traits: pollen shed and silk emergence dates, plant and ear heights, tassel branch number, kernel row number, ear length and diameter, grain yield, and 300-kernel weight. Summarizing for F-tests over all traits and experiments, 30% were significant among sib-mated generations and 56% among selfed generations. Also, overall generation means of the two methods were different for 51% of the comparisons, and the selfed lines were less vigorous for 79% of the significant comparisons. It was concluded that sib-mating lessens the effect of genetic instability and that a reproduction system of sib-mating with intermittent generations of selfing may be more beneficial than continuous ear-to-row selfing for certain lines.Joint contribution: USDA-ARS, and Journal Paper No. J-11880 of the Iowa Agric. and Home Econ. Exp. Stn., Ames, IA 50011. Project No. 2194. 相似文献
16.
Marine J. Paupière Pauline van Haperen Ivo Rieu Richard G. F. Visser Yury M. Tikunov Arnaud G. Bovy 《Euphytica》2017,213(6):130
Among the abiotic stresses affecting plant reproduction, high temperature is one of the most prominent ones because it directly affects fruit set. So far, little attention has been paid to the investigation of the variation in high temperature tolerance among wild tomato (Solanum lycopersicum) germplasm. The objective of this study was to determine the tolerance of 17 different cultivated and wild tomato accessions to high temperature, using a pollen viability screening approach. Each of the 17 genotypes of tomato was analysed for their pollen quality under a 32 °C (day)/26 °C (night) regime. The total number of pollen per flower and the fraction of viable pollen were recorded. The number of pollen per flower varied between 35,547 and 109,490 whereas the fraction of viable pollen varied between 0.03 and 0.71. No correlation was found between these two traits. However, the combination of these traits could provide the best reproductive capability under high temperature. In this study, thermo-tolerant (LA2854, LA1478 and LA0417) as well as thermo-sensitive (LA1719, LA1580, and SWEET4) genotypes have been identified. Those genotypes can be used as novel genetic resources to get more insight into pollen thermo-tolerance mechanisms and be included in breeding programs. 相似文献
17.
A pollen selection study for drought tolerance using Poly Ethylene Glycol (PEG) as a selective agent was conducted in sorghum.
Ten genotypes of sorghum suitable for post rainy season were crossed to cytoplasmic male sterile line 104A and three genotypes
to 116A producing 13 hybrids. Two sets of 13 hybrids with and without pollen selection were produced. PEG at 36 per cent was
applied to stigma and stylar tissue one hour before pollination for pollen selection (selective fertilization) and no treatment
for control (nonselective fertilization). Hybrids thus produced through selective and non-selective fertilization were tested
in moisture stress environment during post rainy season. The hybrids obtained through selective fertilization produced significantly
higher mean grain yield compared to hybrids obtained through non-selective fertilization. The results indicate that selective
fertilization through in vivo pollen selection using PEG as selective agent was effective in improving moisture stress tolerance of the progeny in sorghum
genotypes studied. Further, the pollen selection also had influence on plant height, panicle length, panicle width, panicle
weight and grain mass. Thus,the pollen selection had a significant effect on grain yield through its components and developmentally
related traits. Pollen selection for osmoticstress tolerance in sorghum influences the growth and vigour of the plants resulting
in superior progeny in moisture stress environment. The analysis of individual crosses indicated that pollen genotype selection
was able to favour performance of the progeny. However, the pollen selection had positive effect in majority of the hybrids
and the study demonstrates the transmission of the selected trait from pollen generation to progeny.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
18.
Gene How is a key concern associated with the eonlamination of seed multiplication iields and the use of transgenic crops. The release of herbicide-resistant germplasnis and the use of male-sterile varieties make foxtail millet (Sviaria ilalicii) an appropriate material to inves-tigate this concern. Pollen dispersal from pollen donor sources and gene tlow in fertile and male-slerile varieties of fortail millet were investigated in experiments in China and France. Although foxtail millel is mainly autogamous (less than 2% oiitcrossing), pollen from a 5m diameter plot could fertilize a tertile variety up to 24 ni away, and a male-sterile variety up to 40m. Negative exponential and WeibuU fnnctions were used to tit the relationships between percentage and number i.A iubrids per cm of ear with distance from the pollen source. Wind velocity and direction resulted in variations of gene How intensity, but did nol change liie slope ofthe regression equations. Pollen competition for available target ovules was observed up to 2 m away from a 1 m diameter pollen source. The percentage of pollen grains that fertilized ovules outside the pollen donor source was 1.4% of the total pollen grain produetion. For every iflO pollen grains released under lieid conditions 1.5 seeds were produced. The probability funetion of pollen dispersal for one donor plant was calculated. It allowed predictions of gene How accord-ing to lield shapes, estimations of isolation distances to preserve /ariety purity against pollen contamination, and the fornuiiation of efficient male/female ratios Ibr hybrid seed production. 相似文献
19.
研究温度对白魔芋散粉、花粉萌发、活力保持及自交结实的影响,以离体萌发法测定花粉萌发率,以培养箱法测定恒温自交结实率,以野外套袋法测定自然自交结实率。结果显示:最佳散粉温度22~26℃,18℃低温下可正常散粉,而34~38℃高温下80%以上花株花粉囊无法正常开裂;高浓度钙可加快花粉管的生长;花粉在18、22、26、30、34、38℃下的萌发率分别为8.78%、33.17%、54.90%、38.83%、29.10%、6.98%;花粉在38、34、30、26、22、18℃贮藏下分别在4、4、12、12、25、55 h内丧失活性。恒温培养中仅26℃下有4.35%的自交存活率,野外套袋中日平均温度为23.7℃时有2.94%的自交存活率。白魔芋的散粉培养及离体萌发最佳温度为26℃,温度过高或过低均影响授粉结实率。及时采集花粉、控制温度、调节湿度、适当灌溉均能提高授粉结实率。 相似文献
20.
In sugarcane breeding programs, parents used in crosses are classified as male or female based on relative amounts of viable
pollen produced. Usually the ‘female’ parent produces some pollen, albeit at a lower level than the ‘male’ parent. The possibility
of selfing and associated problems have long been recognised by breeders. A high level of selfing may seriously bias estimates
of breeding value of parents and affect the reliability of family means for identifying superior crosses. However, there is
no reliable information reported indicating the level to which selfing is occurring in sugarcane crosses. The level of selfing
was evaluated in eight Australian sugarcane crosses using RAPD markers. The crosses were selected as exhibiting variable levels
of performance, as judged by measurements of commercial cane sugar (CCS), cane yield (TCH) and sugar yield (TSH) in plots
consisting of random progeny clones. Five to eight male-specific RAPD bands were identified for each cross and used to screen
twenty-eight to thirty-eight progeny from each cross. Selfed progeny were identified in each cross on the basis of absence
of any male-specific RAPD bands after screening with at least 5 such RAPDs. Levels of selfing ranged from 0 to17.6%, with
most of the crosses exhibiting zero or low levels of selfing. Although only a limited number of sugarcane crosses have been
studied, this survey suggests that unwanted selfing is not a significant problem in the Australian sugarcane breeding program.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献