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1.
The genetic basis for crown rust resistance was analysed in the progeny of reciprocal crosses between Lolium multiflorum plants that were either resistant (cv. ‘Axis’) or susceptible to crown rust. The progeny harvested from the resistant parent was two‐ to seven‐fold more resistant than the progeny harvested from the susceptible parent. These data indicate the presence of a maternal factor which increases resistance to crown rust in some of the ryegrass plants used as parents.  相似文献   

2.
The investigation was earned out to obtain double haploid homozygous lines of Lolium. Lolium multiflorurm ssp. gaudini cv. ‘Liwelo’, 44 clones and five different cultivars (cv.) of L. perenne were tested with regard to their anther culture response on a solid medium. Callus production and plant regeneration of the different genotypes were investigated. Within L. m. ssp. gaudini green plants have been obtained. In L. perenne significant genotypical differences in the in vitro reaction could be demonstrated. A high-responding genotype was selected which produced a maximum of 20 % green plants. A variety × temperature interaction was found for the L. perenne varieties ‘Premier’ and ‘Barlenna’. The production of 34 green plants out ot eight clones enables a first analysis to be made of the inheritance of Barley Yellow Dwarf Virus resistance in L. perenne.  相似文献   

3.
Little is known about the extent or diversity of resistance in soft red winter wheat (Triticum aestivum L.) to stripe rust, caused by the fungal pathogen Puccinia striiformis f.sp. tritici. The soft red winter (SRW) wheat cultivar ‘USG 3555’ has effective adult‐plant resistance to stripe rust, which was characterized in a population derived from ‘USG 3555’/‘Neuse’. The mapping population consisted of 99 recombinant inbred lines, which were evaluated for stripe rust infection type (IT) and severity to race PST‐100 in field trials in North Carolina in 2010 and 2011. Genome‐wide molecular‐marker screenings with 119 simple sequence repeats and 560 Diversity Arrays Technology (DArT) markers were employed to identify quantitative trait loci (QTL) for stripe rust resistance. QTL on chromosomes 1AS, 4BL and 7D of ‘USG 3555’ explained 12.8, 73.0 and 13.6% of the variation in stripe rust IT, and 13.5, 72.3 and 10.5% of the variation in stripe rust severity, respectively. Use of these and additional diagnostic markers for these QTL will facilitate the introgression of this source of stripe rust resistance into SRW wheat lines via marker‐assisted selection.  相似文献   

4.
Differences were found in the expression of resistance of perennial ryegrass, Lolium perenne, cultivars to crown rust, Puccinia coronata Corda, when plants were incubated at either 10°C or 25°C. In an extreme example, all the genotypes of ‘Carrick’ were resistant at 10°C but susceptible at 25°C. The variation between cultivars was due both to a general increase in expression of susceptibility and the proportion of plants which became susceptible. A BC1 line containing a stay‐green gene derived from Festuca pratensis was insensitive to temperature, while a sister line was sensitive.  相似文献   

5.
D. Singh    R. F. Park  R. A. Mcintosh   《Plant Breeding》2001,120(6):503-507
Genetic studies were conducted to gain an understanding of the inheritance of adult plant resistance (APR) to leaf rust in six common wheat varieties. The Australian varieties ‘Cranbrook’ and ‘Harrier’ each carry two genes for APR to leaf rust. These genes are genetically independent of the seedling resistance genes Lr23 and Lrl7b, carried by the respective varieties. Adult plant resistance in ‘Suneca’ was conferred by at least two genes, in addition to the seedling genes Lr1 and Lrli. It is likely that the APRs in ‘Cranbrook’, ‘Harrier’ and ‘Suneca’ are conferred by uncharacterized gene(s). Tests of allelism confirmed that seedling resistances in the varieties ‘Avocet R’, ‘Hereward’, ‘Moulin’ and ‘Pastiche’ are conferred by Lrli. Adult plant resistance in the variety ‘Hereward’ was inherited monogenically, whereas varieties ‘Moulin’ and ‘Pastiche’ each carried two dominant genes. On the basis of rust specificity and pedigree analysis, it would seem likely that the APR genes in ‘Hereward’, ‘Moulin’ and ‘Pastiche’ are also currently uncharacterized.  相似文献   

6.
Seed production in perennial ryegrass, Lolium perenne L., is low. Early selection for high seed yield carried out in spaced plants would be valuable for breeders, but only if this potential is also expressed in derived progenies sown later in drilled plots. Therefore, spaced-plant traits assessed on clonal ramets of 31 genotypes in each of two perennial ryegrass varieties in four environments were related to seed production characteristics in drilled plots of open-pollinated progenies of these plants. Significant differences were found among these half-sib families for seed yield, thousand-grain weight, spring performance and earliness. The number of spikelets per ear in the maternal plants was negatively correlated with the seed yield of the progenies, explaining 17 % of the variation for seed yield in the cv. ‘Barenza’ and 14 % in the cv. ‘Wendy’. Multiple regression analyses revealed that no combinations of plant traits consistently explained a major portion of the variation for seed yield of the progenies. The results indicate that in these varieties, spaced-plant data are of limited value in predicting seed production. Direct selection for seed yield in drills of progenies in later stages of the breeding programme remains the best method for obtaining varieties with sufficient seed production.  相似文献   

7.
Summary Four varieties of Lolium perenne with similar flowering dates bred over a 30 year period were grown in an orthogonal plot trial with two contrasting harvesting frequencies and three levels of fertiliser (0.2, 0.4 and 0.6 t/ha of N annually). In the second harvest year, the nitrogen (N) content of herbage at each harvest was determined and the yields of N calculated. The newest variety (Ba 10761) gave a 20% higher mean annual yield of N than the oldest (S.321). The influence of variety in increasing the ratio of N recovered: N applied was as great or greater than the influence of harvesting frequency or level of applied N. There were small differences between varieties in N content (%N), N content being inversely related to N yield.  相似文献   

8.
Doubled haploid lines derived from anther culture of two Iranian spring wheat genotypes‘Ghods’susceptible and‘9106’resistant to yellow rust in Iranian field conditions, and their F1 hybrids were used in this study. Seedlings of 36 doubled haploid lines, selected out of 96 according to their agronomic traits and the two parental genotypes were inoculated with eight races of yellow rust. The parental genotypes (‘Ghods’and‘9106’) were segregating for some of the races but their doubled haploid lines were either resistant or susceptible to them.‘Ghods’was susceptible to three of the races studied but three doubled haploid lines derived from it were resistant to them. Five selected doubled haploids from the‘9106’genotype and six from F1 hybrid plants were resistant to all eight races tested. After further investigations in Iranian field conditions it was found that some of these lines can be used as donor genotypes for resistance to yellow rust in wheat breeding programmes. Use of these genotypes should be possible if the French yellow rust races used for selection also represent the dominant races in Iran. It can be concluded that anther culture provides an efficient method for fixing genes of resistance to yellow rust and desirable doubled haploids from F1 plants can be derived.  相似文献   

9.
江苏花生新品种鉴定和产量稳定性分析   总被引:2,自引:2,他引:0  
为了准确、客观地评价江苏花生新品种鉴定试验参试品种(系)的特征特性,促进江苏花生新品种的推广应用,采用高稳系数法分别对淮南、淮北组的12个参试品种(系)进行丰产性和稳产性分析,并进行品质、抗性及主要农艺性状调查。结果显示:各参试品种均具有中等以上的耐旱性、耐涝性、叶斑病及锈病抗性。具体来说,淮南组的‘宁泰9922’产量较高,且稳产性较好;‘苏花0537’种皮深红色,熟期早,适应性广,粗蛋白含量较高;淮北组的‘连1001’、‘赣榆10-6’、‘东花9号’及‘徐0627’分别较对照‘徐花13号’增产4.7%~7.4%,同时产量稳定性优于对照。因此认为以上品种可以进一步示范和推广应用,同时也表明用高稳系数法评价花生品种(系)的高产稳产性是可行的。  相似文献   

10.
几种多花黑麦草与紫花苜蓿品种的化感作用研究   总被引:2,自引:1,他引:1  
本文对三个多花黑麦草与两个紫花苜蓿品种的茎、叶和根的水浸提液化感作用进行了研究分析。结果表明:三种花黑麦草与两种紫花苜蓿品种对受体赛迪7有一定的化感影响,对赛迪7的种子发芽都有抑制作用;多花黑麦草 Barextra和Barmega两个品种的根、茎、叶水浸提液对赛迪7的苗高、根长及生物量的积累都存在低促高抑的化感作用;供体不同部位化感作用不同;紫花苜蓿两个品种茎的水浸提液在三种浓度下均对赛迪7的根长有促进作用,对苗高有抑制作用。  相似文献   

11.
Two medium leaf size varieties of white clover (Trifolium repens L.) were grown in mixture with a range of grass species and varieties in a field experiment conducted over 4 years. The clovers were grown singly or as a blend in swards with a tetraploid perennial ryegrass (Lolium perenne L.), a diploid Italian ryegrass (Lolium multiflorum L.) or tetraploid hybrids between these two species (Lolium x boucheanum Kunth). These grasses were also grown in monoculture. Swards were managed in a regime involving two periods of sheep grazing, two periods of cattle grazing and a silage cut in the same year for 4 years. The objectives of this experiment were 3‐fold: (1) to examine the yield and persistency of white clover in highly productive systems with modern perennial, hybrid and Italian ryegrasses; (2) to compare the performance of white clover varieties grown singly in mixture with grasses with their performance together as a blend, and (3) to examine the persistency of new Italian ryegrass varieties, exemplified by AberComo. The clover content of the sward remained high throughout the experiment, with a mean of 31 % overall. Differences in clover yield between plots were largely attributable to the effects of companion grasses. Total yields were very similar in plots containing different clover varieties and in plots where these varieties had been grown singly or as a blend. Grass yields in mixture were greater than those in monoculture but showed similar relative rankings. The diploid Italian ryegrass variety AberComo showed an unexpectedly high yield in the 4th year of the experiment. The implications of these results for strategies for productive, sustainable agriculture using modern white clover and ryegrass varieties are discussed.  相似文献   

12.
为筛选适宜在新疆巴音郭楞蒙古自治州复播种植的花生品种,在巴州地区复播种植6个花生品种,采用灰色关联度分析方法对10个农艺性状进行综合评价,并分析产量与各农艺性状的相关性。结果表明,综合评价中,各花生品种的等权关联度与加权关联度排列位次一致,排列位次为‘吉花4号’>‘四粒红’>‘DF05’>‘远杂9102’>‘DF06’>‘闽花6号’。‘吉花4号’综合性状评价优于对照‘四粒红’,适宜在新疆巴州地区复播条件下推广种植。而花生‘DF05’、‘远杂9102’、‘DF06’、‘闽花6号’的综合农艺性状劣于对照‘四粒红’,不建议推广种植。相关分析表明,产量与出仁率呈显著正相关。研究结果为巴州地区引进花生高产品种提供了材料基础和理论依据。  相似文献   

13.
Two generations of recurrent phenotypic selection for seed yield per plant under controlled pollination were carried out to combine improved seed yield with improved forage grass performance in perennial ryegrass (Lolium perenne L.). Selected and unselected varieties (AberDartand AberElan respectively) and control varieties were grown for seed in pots in a glasshouse experiment and in two field plot experiments over 5 harvest years. Seed yield components and seed yield were measured. Significant improvements in seed yield of the selected AberDart over the unselected AberElan were observed both in individual plants grown in the glasshouse and in field plots. Detailed observations of the individual components of seed yield showed that the increased seed yield of AberDart can be attributed to a higher proportion of ovules forming seeds (% seedset), greater seed number per tiller and more reproductive tillers per plant. This improvement in seed yield of AberDart was also observed when it was grown in field plots with AberElan, experimental selection lines and commercial varieties. AberDart produced more seeds per tiller than the other commercial varieties and selection lines studied. The implication of this approach for the breeding of perennial ryegrass varieties that combine good agronomic performance and acceptable seed yields is discussed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

14.
High grain yield and resistance to stripe (yellow) rust are the most important traits for successful adoption of winter wheat varieties in Central and West Asia. This study was conducted to determine the stripe rust response and agronomic performance of a set of breeding lines recently developed by the International Winter Wheat Improvement Program (IWWIP). Replicated field studies were conducted in 2010 and 2011 using 38 experimental lines, one regional check (Konya) and one local check. Stripe rust scores were recorded at Karshi, Uzbekistan, and Karaj and Mashhad, Iran, in 2010. Grain yield was recorded at two sites each in Uzbekistan (Karshi and Kibray) and Iran (Karaj and Mashhad) and one site in Turkey (Eskisehir). The test lines showed variation for stripe rust severity, grain yield, 1,000-kernel weight, days to heading and plant height. Several stripe rust resistant genotypes were either higher yielding or equal to the local checks at different sites. Based on stripe rust resistance and yield performance in 2010, a set of 16 genotypes was selected and evaluated in 2011. All 16 were resistant at Almaty, Kazakhstan, and Dushanbe, Tajikistan, in 2011, whereas 9 of the 16 were resistant at Terter, Azerbaijan. The genotypes ‘TCI-02-138, ‘Solh’, ‘CMSS97M00541S’, ‘TCI -2-88(A)’ and ‘TCI-02-88(C)’ were consistently resistant to stripe across all sites in both years. Several lines showed high grain yields and superior agronomic performance across four sites in Uzbekistan and one site in Tajikistan. One genotype has been released in Uzbekistan and another in Tajikistan.  相似文献   

15.
The study aimed at: i) assessing the agronomic value of the pure stand (PS), of the complex mixture (CM) and of the binary mixture with each of six white clover genotypes (MWC) of eight grass varieties belonging to four species and contrasting for earliness of flowering; and ii) investigating the relationships of competitive abilities in CM and MWC with some morpho-physiological traits of the grass varieties. CM showed a 24 % dry matter yield (DMY) advantage over mean value of PS but did not outyield the pure stand of the best yielding component. For grass-white clover associations, the DMY advantage as Relative Yield Total over PS of the components averaged 43 %. DMY of the grass varieties averaged across MWC conditions was related positively to total DMY (r = 0.99) and negatively to associated clover DMY (r = - 0.96). Competitive abilities as Relative Yield of the grass varieties in CM and in MWC correlated (r = 0.84) and were both positively associated to DMY, canopy height and inclination of leaves in PS. The results suggested that association of white clover with a grass of moderately high vigour, intermediate earliness and relatively erect leaves may provide the best option for rotational meadows in the experiment environment.  相似文献   

16.
Summary The nucleolar organizer activity of diploid and tetraploid Lolium perenne L. and diploid Lolium multiflorum Lam. varieties was analyzed by the silver staining procedure. Both species show six or twelve Ag-NORs (silver stained nucleolar organizer regions) at the diploid and tetraploid levels, respectively. A positive correlation between the size of secondary constrictions and Ag-NORs was observed.  相似文献   

17.
C. Oertel  F. Matzk 《Plant Breeding》1999,118(6):491-496
Crown rust, Puccinia coronata Corda, causes one of the most damaging foliar diseases in Italian ryegrass, Lolium multiflorum Lam. For introgression of crown rust resistance, highly resistant hybrids of the crosses Festuca arundinacea (2n = 6x = 42) ×L. multiflorum (2n = 4x = 28) and reciprocally, L. multiflorum (2n = 2x = 14) ×Festuca pratensis (2n = 4x = 28) and subsequently resistant recombinant individuals were used as female parents and susceptible cultivars of Italian ryegrass as male parents in three successive backcrosses. The BC3 plants were selfed and crossed mutually. Uredospores of seven different crown rust isolates collected from plants of L. multiflorum, Lolium perenne, F. pratensis, F. arundinacea and L. multiflorum × F. pratensis hybrids were applied to identify the resistance or susceptibility of the parental species, backcrossed, selfed and intercrossed progenies. The various crown rust populations revealed a species-specific capability to infect plants of the Lolium-Festuca complex corresponding to the host species from which the spores originated. Selected BC9 plants, however, were found to be completely resistant to all crown rust populations tested. Successful introgression of the resistance was achieved from F. arundinacea as well as from F. pratensis. The resistance represents a dominant character, apparently based on a strong heterologous incompatibility between host and pathogen. In phenotype, bivalent formation during meiosis and in fertility, the novel germplasms are comparable with the L. multiflorum cultivars.  相似文献   

18.
Anther Culture Response in Perennial Ryegrass (Lolium perenne L.)   总被引:1,自引:0,他引:1  
20 diploid clones from 7 varieties, and 10 tetraploid clones from 3 varieties of Lolium perenne were tested in replicated anther culture experiments. Embryos or calluses, were obtained from all clones, and plants were regenerated from all clones except one. The total yield of plants (albino and green plants) ranged from 0 to 61 plants per 100 cultured anthers among genotypes, and there was a general tendency for tetraploic genotypes to be more responsive. Viable green plants were obtained from 5 diploid and 7 tetraploid clones representing 2 and 3 varieties, respectively. Their origin from reduced pollen was confirmed by a haploid chromosome number in some regenerants and by homozygosity for isozyme loci in spontaneously chromosome doubled plants produced from heterozygous diploid donor plants. A large number of the plants were successfully established in the soil. For most donor genotypes, green plants were rare exceptions, but two diploic clones consistently produced 2.3 and 3.8 green plants per 100 cultured anthers, respectively. Estimates of variance components from replicates with greenhouse and field-grown donor plants showed that genotypes accounted for about 73 per cent of the total variation in yield of embryos/calluses, while only 14—15 per cent of the total variation was due to replicates. Hence at present, emphasis should be placed on die selection of high-response genotypes in material of high agronomic potential.  相似文献   

19.
In the Mediterranean environment, root systems are very important for water utilization. For this reason, the effects of selection for increased root dimensions upon root and shoot characteristics of a natural population of Lolium rigidum Gaud, were analysed. Two cycles of phenotypic recurrent selection were carried out on a population collected in Nurra (north-western Sardinia, Italy). Plants derived after two cycles of selection, together with unselected plants, were grown hydroponically in a greenhouse. Data on root volume, longest root length, number of stems and leaves, leaf length, shoot and root dry weight were collected from the selected material and also from unselected material for use as a control. An analysis of variance was performed and correlation coefficients were calculated. The increased size of the root system did not have a negative effect on the above-ground biomass and there was genetic variation for root traits in the ‘Nurra’ population. The improved population will be utilized for further breeding work to obtain L. rigidum varieties capable of withstanding dry periods during the vegetative phase.  相似文献   

20.
The protection provided by the leaf rust resistance gene Lr34 against Puccinia recondita f. sp. tritici was studied in the field over two seasons. In leaf-rust inoculated and fungicide-sprayed control plots, yield of RL6058, the ‘Thatcher’ backcross line with Lr34, was compared to that of the susceptible cultivar ‘Thatcher’. Leaf rust severity remained low on RL6058 in both seasons, but was high on ‘Thatcher’. The latent period of wheat leaf rust isolate 3SA132 in flag leaves of RL6058 was 256 h longer than in ‘Thatcher’. The uredinium density on ‘Thatcher’ was 14.4/cm2, compared to 3.7/cm2 flag leaf surface on RL6058. Leaf rust infection of ‘Thatcher’ reduced the total grain yield per plot by 25.4% and 1,000 kernel mass by 15.6%. Leaf rust caused little or no damage on RL6058 and rusted plots outyielded the control plots by 0.3 %. Seed weight of RL6058 was reduced by 0.7%. Compared to previous greenhouse studies, the adult-plant resistance conferred by Lr34 is more clearly expressed in the field. Evaluation of milling and baking quality characteristics revealed that compared to ‘Thatcher’, RL6058 had a higher flour protein content, but that its milling, dough development and baking properties were inferior.  相似文献   

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