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51.
Summary Common blight disease in beans (Phaseolus vulgaris), caused by the bacterium Xanthomonas campestris pv. phaseoli, reduces crop yield and seed quality. Information is needed on the variation of leaves and pods disease reaction to strains of the bacterium after different inoculation methods. Phaseolus vulgaris cultivars Red Kidney Charlevoix, GN Harris, GN 1140, and GN Emerson were inoculated with three different strains of Xanthomonas campestris pv. phaseoli at two inoculum concentrations (108 and 106 bacterial cells/ml) using water soaking, multiple needle, and razor blade inoculation on leaves, and razor blade scratch, dissecting needle, and razor blade cut inoculation on pods. Differential cultivar disease reactions of leaves, pods, or both to the bacterial strains were observed in some cases. Significant interactions among cultivars, inoculation methods, strains, and inoculum concentrations (leaves) were found. A rapid leaf chlorosis developed 6 to 7 days after inoculation. Strains of bacteria did not show specificity in inducing this reaction, but rapid leaf chlorosis was associated with high inoculum concentration and with the water soaking and multiple needle methods. Another experiment was conducted to count the number of living bacterial cells deposited in the leaf tissue after inoculation by different methods. The number of bacteria deposited by water soaking or multiple needle was higher than that deposited by razor blade.Published as Paper No. 8584, Journal Series, Nebraska Agricultural Experiment Station. Research was conducted under Project No. 20–36. 相似文献
52.
53.
Summary Nineteen early maturing, indeterminate common bean parents were crossed with a tester line of normal maturity. All parents, F1 hybrids, F2's, and backcross generations were evaluated at CIAT-Palmira, Colombia. All 19F1 populations flowered and matured almost as early as the respective early parent (mean of 61 vs 59 days). The F2 populations were slightly less early (63 days), but were still earlier than the mean of the two parents (65 days). Additive effects for days to maturity were usually larger than dominance or interaction effects. Narrow sense heritability for days to flower and maturity were high (greater than 0.67), while heritabilities of absolute and relative duration of pod filling were low (0.17 to 0.50). Also, our data indicated that for each day of increase in earliness, yield potential will decrease 74 kg/ha. 相似文献
54.
Summary Protoplasts were isolated from leaves of a single plant of Vigna aconitifolia, a drought resistant grain legume. The protoplasts regenerated and formed colony and calli from which 50 entire plants were regenerated and transferred to field conditions. Only 7 plants survived upto maturity and they flowered and produced pods with seed. The protoplast derived plants showed variation in important characters. Two groups of characters (one with 7 sets and another with 6 sets) were studied in the protoclones. In first group protoclones showed variations in seed germination, maturity age, pod length, pod and seed colour, number of abortive seed per pod and response to field rots, however, not much difference was recorded in pollen stainability and meiotic behaviour in these protoclones. In second group analysis of variants showed significance difference for plant height, rachis-length, length and breadth of mature odd leaflets, seed per pod and weight of seed. The results indicate that protoplast can be source of variation in this crop. However, detailed biochemical and genetical analysis of protoclones are required. 相似文献
55.
Summary Dwarlism in F1 hybrids has been observed in over 100 crosses of dry beans (Phaseolus vulgaris L.) at the Centro Internacional de Agricultura Tropical (CIAT), Cali, Colombia. In each cross, one parent always had small seeds and the other parent either medium or la ge ones. This apparent incompatibility between the two groups of germplasm was controlled by two complementary, dominant genes: DL1 and DL2. Smallseeded bean lines carried gene DL1 and originated in Brazil, Colombia, Guatemala, and Mexico; medium for large-seeded bean lines carried gene DL2 and were from Bolivia, Brazil, Chile, Colombia, Turkey, The United States, and West Germany. Thes two genes have probably played an important role in the evolution of dry bean forms of different seed sizes by serving as a genetic barrier or isolating mechanism, thus limiting free genetic recombination between the two germplasm groups.Apparent differences in the adaptiveness and yielding ability of the two groups of bean germplasm, smallys, medium- and large-seeded, and some breeding implications for manipulation of the genes causing F1 hybrid dwarfism were also discovered. 相似文献
56.
Summary The number of effective factors controlling the inheritance of a quantitative character can be estimated by analysis of F3 lines where the parental lines are homozygous. The procedure is illustrated with data from a study of pod length inheritance in common bean (Phaseolus vulgaris L.). The mean pod length of Sprite, the parent with longer pods, was compared statistically with the means of F3 progenies derived from F2 plants obtained from the appropriate tail of the F2 frequency distribution for pod length. The data indicate that analysis of F3 progenies avoids much of the underestimation of the effective factor number which is characteristic of other procedures. The number of effective factors was estimated to be a minimum of 4 and the correlation between random F2 parents and F3 progeny means was r=0.82.Florida Agricultural Experiment Station Journal Series No. 406. 相似文献
57.
C. Fortes Ferreira M. Gonzaga Pereira A. da Silva dos Santos R. Rodrigues R.E. Bressan-Smith A. PioViana R. Figueiredo Daher 《Euphytica》2003,134(1):43-46
Among the main causes of poor yield in common beans are fungal, viral and bacterial diseases. Common bacterial blight, caused
by Xanthomonas axonopodis pv. phaseoli (Xap), is one of the major bacterial diseases leading to significant losses in Brazil. Chemical control is ineffective, therefore,
the use of resistant varieties becomes an interesting alternative. The objective of the present work was to evaluate disease
resistance under natural infection of the pathogen in 109 recombinant inbred lines (F7) of P. vulgaris originated from the cross HAB-52 (susceptible — snapbean) × BAC-6 (resistant — common bean) in two different environments,
as well as to calculate genetic parameters to assist in the selection of promising materials to be used in the CBB resistance
breeding program. The data of the genetic parameters were
compared to those calculated for the F3 generation originated from the same cross. The heritability results for DI (disease index) and VI (variation index) in F3 were 26.85% and 0.26, respectively, whereas in F7 they were 91.77% and 1.36, respectively. These results demonstrate a potential to be explored for this advanced population,
that in the future, along with other pathogen variability studies and tests in other environments, may provide more information
regarding a more precise evaluation of promising genotypes to be used in common bean breeding programs aiming to obtain CBB
resistant varieties.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
58.
Genetic variability in antibiotic resistance to the greenbug Schizaphis graminum in Hordeum chilense
Hordeum chilense (Roem. et Schult), a native grass of South America, is a source of antixenotic and antibiotic resistance to the greenbug Schizaphis graminum Rondani. The genetic and environmental components of the variability in antibiotic resistance shown by H. chilense were determined by measuring the developmental time, the length of adult life, fecundity and intrinsic rate of population increase of green-bugs reared on this host. The aphids belonged to a clone of biotype C. Plants were cloned to reduce the incidence of environmental variability. Different plant characters appeared to prolong aphid developmental time and reduce the length of adult life and total fecundity. The broad sense heritability and the genetic variability of these plant characters were different. The plant character that affected aphid development appears to differ from that affecting fecundity. 相似文献
59.
普通菜豆品种苗期抗旱性鉴定 总被引:3,自引:1,他引:3
以不同来源的普通菜豆品种为材料,采用盆栽法,设正常供水和反复干旱2种处理,测定11项生理指标,采用灰色关联度理论进行苗期抗旱性指标筛选,通过加权抗旱指数(weighted drought-resistance index,WDI值)和抗旱度量值D(drought resistance comprehensive evaluation values,D值)对供试材料进行抗旱性综合评价并通过聚类分析划分抗旱等级。结果表明,不同指标与综合抗旱指数的关联度大小依次为叶片相对含水量(0.7726)、PSII最大量子产量(0.7607)、叶绿素含量(0.7435)、反复干旱存活率(0.7341)、生物量(0.7329)、茎叶干重(0.7314)、根干重(0.7192)、气孔导度(0.7159)、根冠比(0.7092)、株高(0.7086)、叶面积(0.6910)。基于加权抗旱指数和抗旱度量值D的评价结果存在一定差异,但不同材料的抗旱性排序大体一致。根据抗旱度量值D将供试材料分为高抗、中抗、敏感和高敏感4个级别,各占总数的10%、6%、58%和26%。综上所述,叶片相对含水量、PSII最大量子产量和叶绿素含量等10项指标可用于普通菜豆苗期抗旱性综合评价;加权抗旱指数与抗旱度量值D两种综合指标相结合能够提高鉴定结果的可靠性;50个参试普通菜豆品种中,白金德利豆、跃进豆、兔子腿、圆白菜豆和260205抗旱性强。 相似文献
60.
Summary Two common bean (Phaseolus vulgaris L.) cultivars were used for recurrent backcrossing (i.e., repeated backcrossing to one of the parents) to both parents independently and for congruity backcrossing (i.e., backcrossing alternately to both parents). One cultivar, ICA Pijao of race Mesoamerica, was late maturing, with erect type II growth habit and small seeds. The other was Pinto UI 114 of race Durango, an early maturing cultivar with prostrate type III growth habit and medium seeds. One to three recurrent backcrosses (RBC) to both parents, and two rounds of congruity backcrosses (CBC), were made. Thirty-two random lines from each method along with two parents were compared in a reps-in-set design at two locations (Popayán and Quilichao) in Colombia in 1992–1993.Differences between lines derived through different methods were found for seed yield, 100-seed weight, days to maturity, growth habit, and seed color pattern. The RBC to ICA Pijao produced lines with relatively higher seed yield, smaller seed size, and delayed maturity. Similarly, the RBC to Pinto UI 114 produced lines with reduced yield, medium seed size, and earlier maturity. All lines from one, two, and three RBC to Pinto UI 114 had type III growth habit. While most lines from the RBC to ICA Pijao had erect type II Growth habit, a few type III lines were also found in all the RBC. The lines derived from the CBC mostly possessed yield, maturity, and seed characteristics between those of the two parents and lines derived from RBC to both parents independently. They also had more variation for growth habit. To maximize recombination between and retention of desirable traits from distantly related parents used in interracial crosses, use of the CBC is suggested. 相似文献