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1.
Felicitas Svejda 《Euphytica》1979,28(2):309-314
Summary Heritability in the broad sense and the distribution of levels of winterkill were analyzed in the offspring from hardy diploid and from hardy, semi-hardy and tender tetraploid roses. The heritabilities for different parental combinations ranged from 51 to 92%.The offspring from crosses of hardy parents were also hardy and showed little variation in hardiness levels. The offspring from crosses of hardy roses with the semi-hardy R. kordesii and the tender Queen Elizabeth survived the winters without coverage but showed a wider variation in hardiness levels.The desirable level of hardiness, an average winterkill of less than 10%, could be achieved through selection in the first or second generation of breeding, depending on the hardiness levels of the parents. The hypothesis is advanced that winterhardiness in roses is controlled by very few or closely linked genetic factors.Contribution No. 557 相似文献
2.
GAO Yun ZHANG Yu-Xue MA Quan SU Sheng-Nan LI Chun-Yan DING Jin-Feng ZHU Min ZHU Xin-Kai GUO Wen-Shan 《作物学报》1962,47(1):104-115
Grain yield and the number of grains per ear of wheat decreased under the low temperature after jointing stage. In order to explore the physiological reasons of the decrease of grains number per ear by low temperature in spring, the spring wheat variety Yangmai 16 and the semi-winter wheat variety Xumai 30 were used as tested varieties to analyze the effects of low temperature in spring on the fertility of pollen and the formation of grain numbers at the appearance of the penultimate leaf stage (5℃/-3℃, day/night), booting stage (8℃/-1℃, day/night), and anthesis stage (12℃/4℃, day/night). The results showed that low temperature at the appearance of the penultimate leaf stage and booting stage resulted in abnormal metabolism of starch and protein in the anther both at the binuclear and tri-nuclear pollen stages and delayed degradation of the tapetum. The low temperature at the booting stage caused abnormal meiosis of pollen mother cells, abnormalities in chromosome pairing, which affected the formation of male gametophyte. The abortion rate of pollen was more significantly increased under low temperature at the appearance of the penultimate leaf stage than that at the booting stage, and it was the minimum at anthesis stage. The abortion rate of pollen in Xumai 30 was higher than that in Yangmai 16. The low temperature at three stages had significant effects on the number of spikelets, the number of fertile spikelets and the number of grains per spikelet. The effect of low temperature at the appearance of the penultimate leaf stage on grains number per spikelet was the most significant. There was a significant positive correlation between the number of grains per spike and pollen fertility, which was affected by abnormal meiosis, delayed degradation of the tapetum, and undersupply of nutriment for anther development. Therefore, the decline of pollen fertility caused by low temperature in spring is the main reason for the decrease of grains number per spike. 相似文献
3.
春季低温对小麦花粉育性及粒数形成的影响 总被引：1，自引：0，他引：1
小麦拔节后遭遇春季低温,每穗粒数下降,产量降低。为探明春季低温引起每穗粒数减少的生理原因,以春性小麦扬麦16和半冬性小麦徐麦30为供试品种,研究小麦倒二叶出生期(昼夜5℃/–3℃)、孕穗期(昼夜8℃/–1℃)和开花期(昼夜12℃/4℃)分别进行低温处理对小麦花粉育性及每穗粒数形成的影响。结果表明:倒二叶出生期和孕穗期低温均导致2个小麦品种在二胞花粉期和三胞花粉期花药中的多糖物质淀粉和蛋白质的代谢异常,绒毡层解体延迟;孕穗期低温还造成花粉母细胞减数分裂中染色体配对异常、出现微核等情况,影响正常雄配子体形成;花粉败育率表现为倒二叶出生期低温处理>孕穗期低温处理>开花期低温处理,徐麦30败育率高于扬麦16;3个时期低温均显著降低了2个小麦品种结实小穗数、每小穗结实粒数和每穗粒数,以倒二叶出生期低温处理穗粒数降低的幅度最大。相关分析表明,春季低温引起花粉母细胞减数分裂异常、绒毡层延迟解体、花药营养物质供给不足导致的花粉育性下降,是春季低温导致小麦每穗粒数减少的主要原因。 相似文献
4.
高寒冷凉地区日光温室温度变化规律研究 总被引：5，自引：4，他引：1
为了探明高寒冷凉地区日光温室内温度变化特征,预报温室内温度变化规律,调控温室内温度高低提供依据,利用2012年10月—2013年5月大通县国家现代农业示范园区节能日光温室内外温度及大通县气象观测资料,分析高寒冷凉地区不同天气类型下日光温室温度变化规律。结果表明,高寒冷凉地区试验期间温室内平均温度日变化和秋、冬、春3季温度日变化均表现为典型的“单峰”型。晴天温度最低值出现在08时,多云和阴天推迟1 h;室内温度最大值：晴天＞多云＞阴天,最小值：阴天＞多云＞晴天,导致日较差：晴天＞多云＞阴天,不同季节室内温度日变化有所不同;不同天气类型温室内外各时次、日平均以及最大值、最小值间相关性表现为：阴天＞多云＞晴天,相关系数夜间均大于白天,最低温度在不同天气类型相关性均较高,最高温度晴天、多云天两者相关性不明显,阴天相关性较高;冬季温室内外温差较大,增温效果显著。 相似文献
5.
Successful selection of interspecific hybrid progenies with superior ability to regenerate shoots from apical meristems was
performed in sunflower which now allows for the development of lines for improved biotechnological applications. Early generations
of interspecific hybrids originating from crosses between the two H. annuus CMS lines ‘HA89’ and ‘Baso’, and 9 wild species were screened for their ability to regenerate in vitro. Evaluation of 36 progenies allowed to identify seven progenies from crosses involving H. mollis, H. giganteus, H. strumosus, and H. decapetalus which showed a significantly higher regeneration potential than the commercial hybrid ‘Albena’ regarding the number of shoots
per explant. Among these progenies, 47.2 to 62.4% of explants produced shoots with an average of 2.3 to 3.5 shoots per cultured
explant. Regeneration in vitro was significantly determined by the genotype. More than half of the investigated interspecific hybrids performed better than
the inbred ‘HA89’ demonstrating that the high regeneration potential available in the wild species can be efficiently transferred
to cultivated sunflower. The seven progenies with high regeneration potential in vitro were characterised by agronomic performance in the field. Two of the interspecific hybrids derived from H. strumosus and H. decapetalus not only showed a superior regeneration potential but also proved to be competitive to commercial hybrids with regard to
important agronomic traits, e.g. fat content and TGW.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
6.
Summary F2 and BC1 progenies from crosses between tomato (Lycopersicon esculentum) varieties differing for growth capacity at low temperature were produced under controlled conditions by hand pollination under two temperature regimes (22°C D/15°C N, normal temperature (N), and 15°C D/8°C N, low temperature (L)) with pollen formed under both regimes, resulting in four pollination treatments: NN, NL, LN and LL. Vegetative growth of the offspring was compared under a rather low temperature regime (19°C D/10°C N). Populations from different treatments within the progeny of a particular F1 often differed significantly for average dry weight of 7 weeks old plants, the average of the NN population always being higher. Variances for dry weight were sometimes larger for LN populations, but this never resulted from a larger number of vigorous plants. Differences between populations within each progeny seemed to result in part from differences in the conditions for embryo development. Pollen selection at low temperature did not appear to be efficient for sporophyte breeding in this experiment. 相似文献
7.
Summary A monogenic dominant male sterility is used for hybrid production in autumn and winter cauliflower. The ratio of male sterile plants in the backcross progenies of autumn cauliflower was 1:1 over five years (1987–1991). However, a significant deficit of male sterile plants was observed in the winter type over the same period.The influence of the temperature on the male sterile phenotype was studied within backcross progenies planted inside polythene tunnels. Six classes of phenotype were defined during the flowering period (from May to November). At low temperature, some male sterile plants developed partial to complete male fertility, whereas at high temperature, male fertile plants became male sterile.Segregation among the progenies of self-pollinated unstable male sterile plants did not deviate from the expected 3:1 ratio. Plants homozygous for the male sterility allele have been revealed by test crosses with a male fertile plant.For use in seed production, stable male sterile plants are vegetatively maintained; however, crossing lines isogenic except at the MS locus would allow male sterile plants to be raised from seed. 相似文献
8.
Ernest D. P. Whelan 《Euphytica》1980,29(1):33-46
Summary Interspecific substitutions of the nucleus of Helianthus annuus (2n=34) cv. Saturn into the cytoplasm of H. petiolaris (2n=34) by successive backcrossing, resulted in progenies with indehiscent anthers containing white, rather than normal yellow, pollen. Further backcrossing by cv. Saturn failed to restore pollen shed, suggesting that the male sterility was cytoplasmic. In vivo germination tests of pollen from 23 such plants from eight BC5 lines, indicated complete pollen sterility for 14 plants, but normal seed set, suggesting that female fertility was not affected. Meiosis in all plants examined was normal.Crosses between seven sources of pollen-fertility restorer, one collection of wild H. annuus, and an existing source of cytoplasmic male sterility, resulted in a high frequency of plants with normal pollen shed in all F1 progenies. However, no normal pollen shed was evident in F1 progenies for similar crosses between BC5 male-steriles and three of the seven restorer sources, nor for the single wild H. annuus evaluated. The foregoing suggests that the backcross substitution lines are a new source of cytoplasmic male sterility. The inheritance of restoration of pollen shed was complex and not fully elucidated. Some data suggested that two independent, complementary, dominant genes were required, but others indicated two to three independent, dominant genes. 相似文献
9.
Summary F1 hybrid true potato seed progenies with multiple sources of specific resistance to Pseudomonas solanacearum and adaptation were evaluated under tropical greenhouse conditions for resistance to a race 1 isolate of P. solanacearum. Results indicated that genes for adaptation are involved in conferring resistance to bacterial wilt. The effect of a particular resistant parent clone on the resistance level of its progeny depended on the resistance, adaptation or the combination of both characteristics of its mate. A heat tolerant parent gave a higher frequency of resistant offspring in combination with an ascertained source of resistance. Combining ability was an apparent feature of resistance to bacterial wilt and resistance was highest in the majority of the crosses that had a wide genetic background for both resistance and adaptation. The possible genetic nature of the resistance to bacterial wilt is discussed. 相似文献
10.
Storage of broccoli pollen in liquid nitrogen 总被引：2，自引：0，他引：2
Summary Broccoli pollen which had been stored in liquid nitrogen retained its viability, but seed produced using this pollen rapidly lost its germinability. Plants raised from this seed, and their progenies, gave no indication of genetic damage resulting from the low temperature treatment of pollen. 相似文献
11.
Summary
Cicer echinospermum, a wild relative of chickpea (Cicer arietinum L.), has traits that can be used to improve the cultivated species. It is possible to obtain successful crosses between the two species, even though their cross progenies have reduced fertility. The reasons for this low fertility could be due to the two species differing in small chromosome segments or at genic level. Another limitation to the use ofC. echinospermum at ICRISAT Asia Center is that the species is not adapted to the short photoperiod which prevails during the chickpea cropping season at Patancheru, Andhra Pradesh, India. Future work will include screening the segregating progenies for monitoring traits from both the species through isozyme analysis and to incorporate these into good agronomic backgrounds following backcrosses.Submitted as JA 1669 by ICRISAT 相似文献
12.
为探求内蒙古高寒地区日光温室小气候变化特征及预测预报方法,利用内蒙古赤峰市宁城县2012-2013 年度春、秋、冬季日光温室内外气温资料,分析不同季节（春季、秋季、冬季）、不同天气条件（晴天、阴天）、一日内不同时段（白天、夜间）温室内气温变化特征和增温保温效应及温室内气温的变化与一日时间变化、室外气温的相关性,在此基础上,建立了温室气温日变化及最低气温的预测模型,并对模型的准确率进行了验证。结果表明：模型拟合的准确率较高,可为厚墙体日光温室气象服务提供技术支撑。 相似文献
13.
高温对一季晚稻结实率与产量的影响及其防御技术 总被引：2，自引：1，他引：1
为了寻找湖南省主推一季晚稻品种最佳播种期,避开水稻幼穗分化的减数分裂期与抽穗期的高温热害,通过分期播种,研究不同时期的气温对一季晚稻品种幼穗分化的减数分裂、抽穗灌浆结实及产量的影响,同时调查了湖南省大面积生产的高温热害。研究与调查结果表明：在湘中地区,生育期相对较长的一季晚稻品种最佳播种期是5月20日左右,生育期相对较短的一季晚稻品种最佳播种期是5月30日左右,最安全的幼穗分化的减数分裂期是8月13日后,最安全的抽穗灌浆期则是8月下旬。 相似文献
14.
A male sterile line with dominant gene (Ms) in cabbage (Brassica oleracea var. capitata) and its utilization for hybrid seed production 总被引：4，自引：0，他引：4
Zhiyuan Fang Peitian Sun Yumei Liu Limei Yang Xiaowu Wang Anfu Hou Chunsong Bian 《Euphytica》1997,97(3):265-268
A male sterile plant, 79-399-3, was identified from a spring cabbage line 79-399 in 1979. Light-microscopic studies with paraffin
section indicated that meiotic division stopped at the tetrad stage. The ratio of male sterile plants to fertile plants in
the progenies of test crosses was 1:1 in five experiments conducted in 1982 and 1991–1994. However, some male sterile plants
were sensitive and developed a very low number of viable pollen grains. When sensitive male sterile plants were selfed, the
progenies segregated into male sterile and fertile plants at a ratio of 3:1. The male sterile plants from selfing of sensitive
male sterile plants were propagated by tissue culture and crossed with different inbred lines. From the progenies of the crosses,
populations with 100% male sterile plants were observed. The results indicated that homozygous dominant male sterile (MsMs)
plants segregated from the selfed progenies. Populations with 100% male sterile plants and stable male sterility were developed
as male sterile lines. Several favorable combinations were also selected by crossing the male sterile lines with inbred lines
with high combining ability for desirable horticultural characters.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
15.
Summary The pre-and post-fertilization barriers in the interspecific crosses between Vigna umbellata and V. minima were investigated. In the reciprocal crosses (V. minima as the parent) the entry of pollen tubes into the ovary was delayed by about 4 h, and no seed set was observed. However, no pre-fertilization barriers were encountered in crosses involving V. minima as the parent and V. umbellata as the parent (normal cross). The delay/absence of divisions in the endosperm and the failure of embryo to divide were the post-fertilization barriers responsible for somatoplastic sterility in normal crosses which yielded a few hybrid seeds. The hybrid seeds showed poor germinability. The F1 hybrids were intermediate between the parents in most morphological characters, and are completely sterile for pollen. Backcrossing of F1 hybrid with both the parents did not restore fertility in the progenies. V. minima is considered as the tertiary gene pool of the rice bean. 相似文献
16.
Summary A new cms source, ANN-5, was found in wild Helianthus annuus. This source showed high stability under different conditions in 1991 and 1992. All progenies from crosses of this source with several stable B-lines and restorer lines, which are homozygous for the gene which restores Leclercq's source of male sterility, were completely male sterile. Flower contained pistils and atrophied stamens. The cytological analysis showed that pollen mother cell degeneration took place in a premeiotic stage. 相似文献
17.
G. J. Faulkner 《Euphytica》1967,16(1):45-48
A total of 51 red and white commercial varieties of trench celery were grown and examined for winter hardiness at the National Vegetable Research Station. Although some plants of most varieties survived the winter, none showed a commercially useful degree of winter hardiness, in that none were marketable after moderate frost. The red varieties had a significantly better survival than the white varieties. In the first season, single plant selections were made from the varieties having both the highest percentage of winter survival and the best agronomic characters. Although some of the progenies derived from these selected plants by self-pollination showed a small increase in winter survival as compared with their parent varieties when both were grown in the second season, no plants of these progenies were sufficiently hardy to remain marketable after moderate frost. It was concluded that none of the varieties tested showed any promise as a source of winter hardiness to be used in a breeding programme, and that selection for one generation from within these varieties did not improve winter hardiness to a useful extent. 相似文献
18.
Summary Progeny lines of chromosome-doubled haploids from crosses between one winter and four spring barley varieties were analysed for winter hardiness and vernalization requirement in the field. About one quarter or less of the offspring lines required vernalization under field conditions showing that winter versus spring habit of growth is controlled by at least two pairs of genes. The vernalization requirement could be measured quantitatively by testing a few plants in a greenhouse after artificial cold treatment during germination. The individual winter lines tested required from two to seven weeks of vernalization in order to flower as early as possible. The cold treatment had no effect on the time of flowering in the spring lines.Winter hardiness varied from zero to 100% plant survival in the field. The majority of the lines requiring vernalization survived better than 90% and the survival of the rest was at least 60%. The winter survival of the spring lines varied from zero per cent (about one third of the lines) to 100%. Hence, it is possible to obtain lines of good winter hardiness without requirements for cold treatment. Conversely, a selection for vernalization requirement has a positive effect on winter hardiness. 相似文献
19.
苏北地区日光温室能量分配动态研究 总被引：1，自引：1，他引：0
为了进一步提高日光温室保温性能,减轻温室内低温寡照灾害发生,以苏北（徐州）番茄日光温室为研究对象,利用采集的2010年12月-2011年4月温室小气候数据及番茄发育数据,根据日光温室小气候形成的物理过程与机理,系统研究了冬春季节不同天气类型及不同叶面积指数对温室能量分配的影响。结果表明：日光温室内潜热、显热随着室内总辐射量的改变而发生变化,阴天以显热消耗为主,潜热消耗量全天低于显热;晴天日光温室内用于作物蒸腾的能量显著多于阴天,阴天室内外贯流传热消耗的能量远远多于晴天;随着叶面积指数增大,到达地面的太阳辐射减少,地面升温慢,室内空气与地表的显热交换量减少,同时室内空气与墙体的显热交换增加。本研究结果可为温室的结构优化及冬春季节日光温室管理提供科学依据。 相似文献
20.
R. Barba-Gonzalez K.-B. Lim M. S. Ramanna R. G. F. Visser J. M. Van Tuyl 《Euphytica》2005,143(1-2):67-73
Cytological modes of the origin of 2n gametes were investigated in six different genotypes of F1 hybrids between Oriental and Asiatic (OA) lilies (Lilium, 2n = 2x = 24). Chromosome pairing between the parental genomes was very low, the average frequency range from 0.3 to 1.2 bivalents per cell among the genotypes. Within a genotype the frequency of bivalents varied from 0 to 6 in some cases. The normally occurring haploid pollen grains were totally sterile. In contrast, in different genotypes, variable percentages of 2n pollen were found and shown to be fertile as estimated from pollen germination. A cytological analysis of Metaphase I and subsequent stages of meiosis using genomic in situ hybridization (GISH) revealed that there was intergenomic recombination between the alien genomes. Following Metaphase I stage, three different types of abnormal cytological events led to the formation of 2n pollen: (i) Post-Metaphase I division (PMI), (ii) Post-Metaphase II division (PMII) and (iii) Asymmetric Cytokinesis of the pollen mother cell followed by chromosome division. All three cytological events led to first division restitution (FDR) gametes. Based on in vitro pollen germination it was proved for two genotypes that 2n pollen was viable only during the first day of anthesis. It was possible to use 2n pollen successfully for backcrossing. Implications of 2n pollen for intergenomic recombination in BC1 progenies are discussed. 相似文献