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1.
In the first two clonal generations of a potato breeding programme, clones are visually selected for ‘plant appearance’. Selection for plant appearance based on unreplicated small plots is unreliable, due to significant genotype × environment interaction and high error variance. In order to improve the selection efficiency, component traits of plant appearance were identified and the effect of selection for these components was studied. Tuber yield was found to be the principal component of plant appearance while stolon length and tuber appearance contributed significantly, but to a lesser extent. Tuber yield had a higher heritability than plant appearance. Characters determining the appearance of stolons and tubers were found to have equal or lower heritabilities than plant appearance at 80 days after planting and somewhat higher heritabilities than plant appearance at 145 days after planting. Hence, since the expected and observed selection responses of the component characters have been found to be equivalent to that of plant appearance, selection for plant appearance cannot be improved upon by separately selecting for characters like tuber yield and tuber appearance. 相似文献
2.
Effectiveness of in vitro selection for agronomic characters was studied by finding correlation coefficients between in vitro
and in vivo performance of 22 potato genotypes. Evaluation was performed under eight in vitro and two in vivo conditions.
Genotypic differences were highly significant for various characters under all in vitro and in vivo conditions. Error mean
squares were much lower in in vitro experiments than in in vivo experiments. In vitro selection was found to be highly effective
for tuber colour, stem pigment and number of eyes, and moderately effective for average tuber weight, plant vigour and foliage
senescence under specific conditions. The results also indicated the possibility of in vitro selection for heat tolerance.
For tuber yield and number of tubers, effectiveness of in vitro selection was low to very low, because differences in phenotypic
expressions of genotypes were much enlarged under in vitro conditions compared to under in vivo conditions. Correlation coefficients
for certain characters were better when in vitro conditions were closer to in vivo conditions. To improve the efficiency of
in vitro selection, there is perhaps a need to simulate and identify the in vitro conditions under which genotypic differences
are reflected in phenotypes more realistically as they are expressed under in vivo conditions.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
3.
甘薯主要数量性状对单株产量的通径分析 总被引：10，自引：2，他引：8
用秦薯1号自交后代实生苗为试验材料,试验对甘薯的分枝数(x1)、最长蔓长(x2)、分枝总长(x3)、节间长(x4)、蔓粗(x5) 、叶面积(x6)、单株绿叶重(x7)、藤叶重(x8)、单株薯数(x9)、单薯重(x10)、根冠比(x11)和单株产量(y)12个数量性状进行了测定。通过相关分析、逐步回归和通径分析表明单株绿叶重对单株产量的影响最大;单株薯数和单薯重对单株产量的直接作用较大。高产育种以单株产量为选择目标时,应以单株绿叶重、单株薯数和单薯重的选择为主,结合根冠比、分枝数、叶面积和蔓粗,对这7个性状进行综合考虑和选择。 相似文献
4.
引进马铃薯种质资源在干旱半干旱区的表型性状遗传多样性分析及综合评价 总被引：3，自引：0，他引：3
马铃薯种质资源缺乏,适宜干旱半干旱条件下生长的品种更为紧缺,引进马铃薯种质是丰富种质资源的有效途径。本文采用Shannon-Wiener’s多样性指数及综合得分(F值)对119份从秘鲁国际马铃薯中心引进的马铃薯材料的表型性状(出苗率、株高、茎粗、叶面积、生育期、单株结薯数、单株产量、商品率、干物质含量和块茎长宽比)进行遗传多样性分析及综合评价。结果表明,参试材料的10个表型性状中生育期遗传多样性最为丰富;茎粗、叶面积、生育期、单株结薯数、单株产量、商品率、干物质含量、块茎长宽比对马铃薯种质资源表型性状综合值具有显著影响,这些指标可用于旱作条件下对马铃薯种质资源的综合评价;综合得分F值与所测经济性状(单株产量、商品率、干物质)具显著相关性,可作为马铃薯种质资源的主要评价指标;引进材料中CIP393228.67和CIP 385561.124在干旱区,CIP304350.95、CIP392797.22、CIP388615.22在半干旱区分别表现出较好的丰产稳产特性。这些材料综合评价较好,可有效补充中国马铃薯种质资源。 相似文献
5.
为研究马鞍型白及组培种茎主要农艺性状与全株重、块茎重的关系,选取30份种茎为研究材料,对全株重、块茎重与其他农艺性状进行相关性分析和通径分析。结果表明:各农艺性状与全株重、块茎重的相关性存在差异。全株重与株高、块茎总分叉长和宽呈极显著正相关,与茎宽、根数呈显著正相关;块茎重与块茎总分叉长、宽呈极显著正相关,与茎宽呈显著正相关。以块茎总分叉长、叶片数对全株重的直接作用最大,通径系数分别为0.464、-0.133;以块茎总分叉长、总叶片长对块茎重的直接作用最大,通径系数分别为0.596、-0.398。研究得出,马鞍型白及组培种茎总分叉越长,全株重和块茎重越大,在生产上,白及组培驯化苗应选取块茎总分叉较大的种茎作为优质种苗。 相似文献
6.
为了研究江淮地区燕麦籽粒生产的影响因素,选取了13个皮燕麦种质和7个裸燕麦种质,对其12个主要农艺性状和籽粒产量进行了相关性分析和通径分析。结果表明,12个农艺性状与皮燕麦籽粒产量的相关性大小依次为分蘖数>茎叶比>株高>茎粗>千粒重>穗长>旗叶宽>轮层数>小花数>穗鲜重>旗叶长>小穗数;对逐步回归分析筛选出的6个农艺性状和皮燕麦籽粒产量做通径分析,其直接效应依次为茎粗>分蘖数>茎叶比>穗长>株高>千粒重,株高和千粒重为负效应。农艺性状与裸燕麦籽粒产量相关性依次为小花数>旗叶长>小穗数>茎粗>穗长>分蘖数>穗鲜重>株高>轮层数>旗叶宽>茎叶比>千粒重;进行通径分析后,直接效应大小为穗鲜重>穗长>茎粗>小穗数>小花数>旗叶长>分蘖数,旗叶长和分蘖数为负效应。综合考虑,皮燕麦籽粒丰产的关键在于增加单株分蘖数;裸燕麦的生产过程中则要选择小穗性状优良、小花数适中的品种。 相似文献
7.
B. Maris 《Euphytica》1966,15(1):18-31
About 2,600 potato clones of 29 combinations were repeatedly analyzed for some years at a stretch in order to determine the degree of modifiability of both a large number of separate characters and the general impression of underground plant parts on lifting in an early stage, in the mature condition and on assessing tuber samples.The ultimate aim of these investigations was to find out how far strictness is justified when selection is applied in breeding new potato varieties. Therefore correlations between the clonal generations were calculated from the data obtained for the various characters and the general impression. Only those characters for which these correlations are positive and high, i.e. slightly modifiable characters, can be strictly selected. Flesh colour appeared to be slightly modifiable. This also applies to tuber shape and maturity though these characters are somewhat more modifiable. Considerably to even strongly modifiable are eye depth, stolon length, under water weight and sprout length. Foliage type, stolon number, date of emergence and degree of common scab affection are extremely modifiable. The same is true for the general impression in the three stages mentioned above.As the general impression, in which the various separate characters and such characters as tuber number, size and yield are included, is initially decisive as to retention, it cannot but be concluded on the ground of the results obtained by others and the author that on a strict selection the major part of the most valuable individuals will be lost. This can be avoided if the negative selection takes the place of the positive in the first stages, i.e. instead of retaining only the apparently good ones the very poorest clones should be discarded in every selection stage. Not until the number of tubers suffice to lay out statistically justified tests can a change be made from the negative to the positive selection. 相似文献
8.
Identifying plant architectural traits associated with yield under intercropping: Implications of genotype-cropping system interactions 总被引：1，自引：0，他引：1
Increased yields of some crops have resulted from indirect selection of plant architectural traits related to yield. This study examines the potential relationship between plant architecture and yield for a legume grown under intercropping, Field experiments were conducted in 1991 to examine the response of two cowpea (Vigna unguiculata (L.) Walp.) genotypes with contrasting plant habits to sole crop and intercrop with pearl millet (Pennisetum americanum (L.) Leeke), and to identify cowpea traits associated with yield under intercropping. The cultivur with a bush-type habit was higher-yielding in sole crop, whereas the cultivar with a spreading habit was higher-yielding in intercrop. For F2 cowpea populations, pod number was most highly correlated with seed yield in intercrop. The number of branches and nodes, particularly in areas with increased access to light, and increased internode length were also important in intercrop. Selection for improved yield in sole crop may not necessarily lead to improved yield in intercrop, and different plant traits may be more appropriate for cultivars intended for use in inter-crop than for those intended for use in sole crop. 相似文献
9.
春马铃薯种薯大小对其植株性状及产量的影响研究 总被引：1，自引：0，他引：1
该文选用过翻秋的小整薯作种进行春播试验，探讨了不同大小种薯对植株性状和产量的影响及其经济效益。结果表明，从植株性状和产量上看，每窝种薯数在１－４范围内，随着种薯数的增加，每窝基本茎数增加，出苗后第３０天冠层覆盖度增加，株高降低，茎粗变细，结薯数增加，埠茎产量变化不大，单个块茎重减少，大中薯数变化不多，大中薯重下降，大中薯数率和大中薯重率降低，其中每窝和薯数与基本茎数，出苗后第３０天的冠覆盖，株高， 相似文献
10.
J. E. Parlevliet 《Euphytica》2007,153(3):353-362
Improved cultivars loose their identity and healthiness unless maintained properly. Contaminating and degrading forces, such
as outcrossing, volunteer plants, mixing, natural selection, mutation and seed-borne diseases, are at the root of this. Maintenance
selection can prevent this deterioration. How it is carried out depends on the reproduction system of the crop. Crops are
therefore classified into four categories; typical cross-pollinating crops, self-pollinating crops with a substantial amount
of outcrossing, typical self-pollinating crops with little outcrossing, and the vegetatively reproduced crops.
Generally some of the “breeder seed” is used to plant a small plot with spaced plants. A fair number of healthy plants of
the cultivar type is selected and the seed is harvested per plant. The progenies of the selected plants are grown in small
plots. Non-uniform or deviating plots and plots with a seed-borne disease are removed. The seed of the progenies that are
healthy, uniform and similar (and so of the cultivar type) are harvested per progeny to be tested next season on larger plots.
The same selection is applied and only the seed of the progenies that are healthy, uniform and similar are harvested together
to produce the “breeder seed”. The details of this maintenance selection vary with the reproduction system, the multiplication
rate of the crop and the possibilities available to the breeder. Seven crops, potato, common bean, barley, wheat, faba bean,
quinoa and maize are discussed here as they represent the different reproduction systems and multiplication rates, while being
important Andean food crops. 相似文献
11.
J. Brown 《Euphytica》1987,36(3):711-718
Summary The efficiency of single plant selection in the initial selection stage of a potato breeding programme was examined. A random sample of potato clones was grown in single plant plots and also in tworeplicates of five plant plots. After harvest, each plot was visually assessed by three potato breeders; total tuber weight and number of tubers per plant were also recorded, from which mean tuber weight was calculated. The error variances of the single plant plots were found to be significantly greater than from the five plant plots for total tuber weight, mean tuber weight and number of tubers per plant, but not significantly different for breeders' preference. Coefficients of correlation between single and five plants plots were significantly greater than zero for all traits examined, but they were lower than the corresponding correlations between the two replicates of five plant plots. Although a random sample of clones was examined, each clone had been assessed for breeders' preference the previous year. When the clones were grouped according to the previous years preference scores, it was found that the correlation coefficients between single and five plant plots for breeders' preference were inversely related, in magnitude, to the mean preference score of each group. It was concluded that single plant selection was generally ineffective, particularly when only the better clones, from the previous years assessment, are examined. 相似文献
12.
Summary Tuber characteristics of potato clones (Solanum tuberosum L.) regenerated from cultured leaf, rachis or stem pieces of cv. Desiree were assessed in field trails over three years. In the first two seasons, when the crop was grown for seed potato production, tuber numbers and the tuber yields were normally distributed and the population means of the clones were about the same as those of the controls. When 78 of the clones were grown as a ware crop in a replicated field trial there were statistically significant differences between most clones and the controls in total yield (generally lower) and ware yield (generally higher), brought about by alterations of the size distributions of tubers. In all years the population of clones had fewer scab (Streptomyces scabies) lesions than the controls. Clones with consistent differences in flesh colour and eye depth were also observed. Two out of 78 clones, in 1984, had significantly higher dry matter content. No stable decrease in susceptibility to the cyst nematode Globodera pallida was observed amongst 167 clones tested. These potato plants regenerated from explants clearly show that somaclonal variation can include agronomically relevant changes. 相似文献
13.
Experiments were conducted with early segregating generations of a selected narrow-leaf lupin cross to determine the effectiveness of selection for yield based on alternative criteria. F2 plants were selected on the basis of seed yield and several other yield-related characters to generate separate F3 populations. Randomly selected plants from each population were grown over the summer (off-season) in a glasshouse to generate F4 populations. Analyses of relationships between F2 plant measurements and F3 progeny mean yields revealed significant correlations only for those characters with the highest heritabilities - flowering time, 100 seed weight and harvest index. However, selection for the earliest flowering F2 plants followed by selection within this group of plants with the highest number of pod bearing branches would result in the greatest increase in F3 mean yield. The F2-derived F4 populations with the highest seed yields were those obtained by selection for total plant dry weight, number of pod bearing branches and number of pods per plant. Improvement in commercial crop yield should therefore be obtained through selection in early generations for those characters contributing to the greatest number of pods per unit area. A scheme involving selection for early flowering and high number of pod bearing branches in the F2 combined with replicated yield tests in the F4 is proposed. 相似文献
14.
干旱胁迫对彩色棉花农艺、品质性状及水分利用效率的影响 总被引：1，自引：0，他引：1
为了探索干旱胁迫对彩色棉花主要性状的影响及其水分利用机理,选用7个不同色彩的棉花品种(系),在常规灌溉、胁迫灌溉和生育期不灌溉3种环境条件下,调查其农艺性状、品质性状、水分利用效率(WUE)及产量。结果表明,干旱胁迫下不同色彩棉花品种的单株成铃数、单铃重、株高、花铃期叶片数、有效果枝数、收获指数、果节数、籽指、茎粗和果茎节间长度减少,衣分增加;灌水量减少一半,参试棉花品种的产量均降低,不灌溉处理的籽棉产量与常规灌溉间差异显著(P<0.05);籽棉产量的降低幅度品种间存在较大差异(P<0.05),棕色棉的减产幅度高于绿色棉。常规灌溉处理下,白色棉花水分利用效率高于棕色棉花和绿色棉花,而后二者差异不显著;干旱胁迫下,棕色棉花的水分利用效率高于绿色棉花。与水分利用效率相关的主要农艺性状、品质指标是：叶片数、单株成铃数、有效果枝数、果节数、株高、收获指数、单铃重、主茎节间长度、茎粗、籽指、衣分。 相似文献
15.
最佳种植密度有利于对不同叶型马铃薯品种的田间管理,而且在高产同时可以获得最佳产量组分。为研究马铃薯叶型和种植密度的相互关系,找到不同叶型品种的最佳种植密度,选取株型直立的中晚熟代表品种Atlantic（叶上冲型）和甘农薯7号（叶平展型）,固定行距70cm,设置30、25、20、15和10cm 5个株距,测定了植株性状、叶绿素荧光参数和块茎产量组分,并分析了不同种植密度下2个品种性状差异以及植株性状和产量组分之间的相关性。田间鉴定表明,随着种植密度的增加,2个品种的株高、节间距、披垂度和叶面积指数增加,茎粗、垂角和叶夹角降低,光合系统Ⅱ最大光化学效率Fv/Fm增加,但实际光化学效率ΦPSII降低。相对于叶上冲型品种Atlantic,叶平展型品种甘农薯7号披垂值显著增加。株距为15~30cm时,2个品种种植密度的提高均可以显著增加单株产量、单株结薯数和小区产量。结果表明,叶平展型品种甘农薯7号在株距25cm、叶上冲型品种Atlantic在株距20cm时,植株冠层结构分布最佳,商品薯率和小区产量较高,为最适种植密度。 相似文献
16.
木薯单株产量与主要农艺性状的相关性研究 总被引：3，自引：0，他引：3
探讨木薯单株产量与主要农艺性状的相关性,以提高木薯育种效率,为木薯品种选育奠定基础。采用13 份木薯种质资源为试验材料,通过相关与通径分析等方法,探讨了11 个主要农艺性状与单株产量之间的相关性以及不同种质资源单株产量之间的差异性。结果表明：NK-2、NK-6、NK-7、NK-10、NK-11、‘新选048’与‘华南205’之间的单株产量呈显著差异;单株产量与块根数呈极显著正相关,与收获指数、生物产量、最长薯长、主茎高度呈显著正相关,与干物质含量呈显著负相关;通径分析结果表明,各农艺性状对单株产量的直接通径系数和决定系数的大小顺序一致,依次为：块根数、最长薯长、生物产量、主茎高度、叶保留高度、干物质含量、收获指数、地上部鲜重、淀粉含量、主茎粗、株高。由此表明,选育高产木薯需要关注的主要农艺性状有：块根数、最长薯长、生物产量、主茎高度、叶保留高度、干物质含量、收获指数等。 相似文献
17.
采用二因素随机区组试验设计,通过测定苗鲜重、根鲜重、苗干重、根干重、叶片数、株高、茎粗、根长、根条数、节长、节数和叶面积等生长指标,研究了品种和外植体对马铃薯脱毒试管苗生物量,地上部和地下部的影响。研究结果表明:3个不同成熟期品种、3种不同外植体部位对马铃薯单株根鲜重、苗干重、根干重、株高、茎粗、节长和根冠比影响有显著性交互作用(p<0.05),说明不同品种和外植体对马铃薯脱毒试管苗生长发育有直接影响,其余性状受品种和外植体交互作用影响不显著;3个不同成熟期品种马铃薯的苗鲜重、根鲜重、苗干重、根干重、叶片数、茎粗、节长、节数、根冠比和根条数受品种影响显著(p<0.05),其余性状受品种影响不显著;3种不同外植体处理对马铃薯的根鲜重、苗干重、根干重、株高、茎粗、节数、叶面积和根冠比有显著性影响(p<0.05),其余性状受3种外植体的影响不显著。其中,以一个节段转接最有利于马铃薯脱毒试管苗的生长。 相似文献
18.
在陇东旱塬区正常的土壤环境和气候背景下,测定了全膜双垄沟播玉米田覆盖化学除草地膜对后茬亚麻生长发育的影响。结果表明,全膜双垄沟播玉米田覆盖化学除草地膜,其后茬亚麻的出苗率、密度（幼苗期至成熟期）、株高（枞形期至成熟期）、根部干重（枞形期至始花期）、地上部干重（枞形期至始花期）、果粒数、千粒重和产量较覆盖普通白色地膜处理分别降低2.21%、3.39%~3.67%、0.04~2.05cm、0.00~6.33mg/株、8.33~84.67mg/株、0.55粒/果、0.06g和2.66%,有效分茎数、蒴果数则较覆盖白色地膜处理分别增加0.04个/株和0.69果/株。但除地上部在始花期的干重在2种地膜处理间有显著差异外,其他各主要农艺性状及产量均在2种地膜处理间无显著差异。综合看出,全膜双垄沟播玉米田覆盖化学除草地膜对后茬亚麻主要农艺性状及产量均有一定的影响,但其效应多较弱,具有一定的安全性。当茬口安排趋紧时,对于覆盖了化学除草地膜的全膜双垄沟播玉米田,其后茬可安排种植亚麻。 相似文献
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Reciprocal crosses may have significantly distinct performances regarding tuber characteristics in potato, suggesting the importance of cytoplasmic effects in this crop. The selection of parents for true potato seed breeding therefore needs to consider this potential effect when determining the direction of a cross. The aim of this research was to determine whether a broad‐based true potato seed breeding population, developed at the Centro Internacional de la Papa, could be affected by cytoplasmic effects in the short‐day length environments of the tropics. Two random sets of reciprocal biparental crosses were included in the first set of experiments, which were grown in two contrasting Peruvian locations. Only one out of 14 reciprocal crosses showed significantly distinct performance for tuber yield and tuber set. In the second set, only one of each of the 12 reciprocal crosses had distinct performance for vine earliness, days to flowering and flowering intensity, but four of the reciprocal crosses in the second set showed distinct pollen production. The results suggest that cytoplasmic effects in this breeding population are more important for reproductive characteristics such as pollen production than for tuber yield. This finding is not surprising because male sterility in potato results from the interaction between sensitive cytoplasm and dominant nuclear genes. 相似文献