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1.
从常规育种、高产育种和抗性育种方面综述近年来国外橡胶树育种研究的新进展,并结合我国橡胶树育种现状,提出我国橡胶树育种的方向,以期为我国橡胶树产量性状、遗传改良和抗逆性育种等提供借鉴.  相似文献   

2.
综述了近年来国内外花卉品质改良研究进展.常规育种虽然是花卉品种改良的主要方法.但有其局限性.现在日益成熟的生物技术为花卉品种改良提供了新的方法,分子育种已在植物的花色、花型、花期、花香、花卉保鲜、抗性等方面取得了一定的成果.  相似文献   

3.
冯九焕 《西北植物学报》2022,42(10):1779-1800
中国食用向日葵育种近40年来取得了巨大成就,实现了从自留农家种、选育常规品种、引进国外杂交种以及培育国产杂交种4 次品种更新。中国向日葵种植面积基本保持在59万hm2左右,种植区主要集中在北方10个省区,其中内蒙古自治区种植面积约占全国总面积的四分之三,其次是新疆。中国以食用向日葵种植为主,约占总面积的95%以上,是世界上食用向日葵主要生产国。食用向日葵主要用于休闲嗑食,除高产外,商品外观品质(粒型、色泽、口感等)仍将是当今主要育种目标。另外,向日葵生产区因长期连作种植,病原菌、列当等生物逆境因素与向日葵发生协同进化,加之食用向日葵遗传背景狭窄,病虫草害日趋严重。该文通过对中国食用向日葵育种历程进行回顾,尤其对国内外有关向日葵抗病育种研究进展进行综述,为解析食用向日葵抗性育种机制以及前瞻性抗性品种储备提供重要的理论与技术支持,以推动食用向日葵产业的高效优质发展。  相似文献   

4.
燕麦分子育种研究进展   总被引:1,自引:0,他引:1  
燕麦是一种主要生长在温带冷凉地区的粮饲兼用作物,近年来燕麦的营养价值和降低胆固醇特性的发现使人们认识到燕麦及其制品是一种健康食品,促进了燕麦产业发展,对燕麦品种培育提出了更高要求。在此背景下,现代生物技术与常规育种技术结合是满足这一需求的重要途经。本文综述了国内外燕麦分子育种方面的研究进展:(1)我国燕麦种质资源的收集与遗传多样性研究。我国的燕麦种质资源收集工作起始于20世纪50年代,迄今收集并保存了5282份燕麦种质资源。对这些资源的遗传多样性分析研究表明,国内的燕麦种质资源中内蒙古和山西的资源多样性最高;(2)利用各种分子标记构建燕麦遗传连锁图谱研究;(3)一些重要农艺性状的QTL定位研究以及全基因组关联分析研究。包括产量、含油量、β-葡聚糖含量、蛋白质含量、抽穗期、抗病基因、抗冻性等重要农艺性状;(4)标记辅助基因组选择技术在燕麦中的应用;(5)燕麦遗传工程育种研究进展。同时,本文将国内的主要研究进展与国外相关的最新研究成果进行了比较,并对当前分子育种中存在的问题及今后的研究方向进行了探讨,希望能为今后通过生物技术手段培育燕麦新品种提供一定的参考。  相似文献   

5.
模拟黄腹角雉野外生存环境和自然种群结构,采用较大空间散放与多个体群养相结合的方法进行饲养试验,其笼养繁殖性能比对照组传统对养方式显著提高.通过两年来的试验研究,结果表明:试验组平均产卵量为8.5枚,卵受精率为82.6%,受精卵孵化率为88.7%;对照组平均产卵量5.7枚,卵受精率50.3%,受精卵孵化率72.4%,试验组明显高于对照组.同时对两组间的卵重、卵形、产卵期进行了测定,无显著差异。  相似文献   

6.
We surveyed 16 British zoos and bird gardens to assess the optimal conditions for breeding of captive Humboldt penguins (Spheniscus humboldti). We obtained information on population, enclosure, and husbandry characteristics and related these variables to three measures of per capita breeding success, namely, per capita egg productivity, chick productivity, and hatching success (measured as the proportion of eggs laid that hatched). All three fitness measures increased with an increasing number of breeding pairs and total population size but were not related to population density. Once the effect of number of breeding pairs was removed statistically, chick productivity was found to be highest when nesting boxes were lined with sand and gravel instead of alternative substrata such as twigs or vegetation. Hatching success increased with increasing pool size and was highest in enclosures with concrete floors. Adult mortality in zoos was generally low and appeared related to the use of chlorine in freshwater pools and to the presence of other penguin species in Humboldt penguin displays. Several enclosure and husbandry parameters were not variable enough to assess their impact on reproduction of captive Humboldt penguins. Recommendations for optimising conditions for captive breeding of Humboldt penguins include keeping as large a population as possible in a concrete enclosure with a large pool area, while providing sand and gravel as nesting material. Bird density may be important but we did not detect detrimental effects on breeding for densities up to 0.25 birds m–2. Adult mortality can be minimised by exhibiting Humboldt penguins in single‐species display and avoiding chlorination of pool water. An experimental approach is recommended to confirm the results of this correlational study. Zoo Biol 20:545–555, 2001. © 2002 Wiley‐Liss, Inc.  相似文献   

7.
生物多样性与林木育种   总被引:5,自引:0,他引:5  
朱大保 《生物多样性》1994,2(3):157-161
保护生物多样性在林木育种中必须予以重视。传统的林木育种主要考虑遗传增益。长期育种则以维持育种群体的变异性为主要目的。具有丰富生物多样性的天然森林群体是长期育种的基础。长期育种研究应以物种生物学、群体遗传学和居群生态学等为理论基础。主要研究森林群体的性质及群体的动态变化规律。传统林木育种的研究方向、研究内容及林木育种学的教学内容等都应予以适当的调整和补充。  相似文献   

8.
The reproductive cycle of the field crab Paratelphusa hydrodromous (Herbst) was determined by direct field observations as well as by calculating the percentage of ovigerous females in a Madras population for a period of three years. The females breed annually in a single spawning. These observations, corroborated by histological studies on the nature of the ovary, indicate that gametogenic activity starts in December and vitellogenesis is completed during January-May. Spawning commences in the last week of June or first week of July with the release of brood in the month of September (1979), October (1978) or November (1980) during northeast monsoon. The smallest female crab showing spawning had a carapace width of 3.1 cm and the largest spawning crabs measured 5.5 mm. The mean number of eggs spawned in the smallest crab was 247 and that in the largest crab was 417. Mean incubation was 41 ± 12.388 days. Vitellogenesis and spawning occurred at peak temperature conditions. Though the time taken for vitellogenesis and commencement of spawning were constant for the study period, the duration of retention of the juveniles in the brood varied with the onset of monsoon.  相似文献   

9.
《Ostrich》2013,84(2):185-191
The Purple Swamphen Porphyrio porphyrio is a common rail that previously was little investigated in North Africa. From 2011 to 2013, its breeding ecology was studied at two natural wetlands in north-east Algeria, namely Garaet Hadj Tahar and Garaet Messaoussa. Numbers of Purple Swamphens at both localities peaked in late April and early May. Egg-laying started in early March, whereas hatching started in late March. Peak egg-laying took place in late March and early April, and peak hatching from mid-April to early May. There were significant differences in the size and weight of eggs between years and localities. The mean clutch size was 2.75 ± 0.70 eggs and it was not signifi- cantly different between localities and years. Mean hatching success was 51% and it was positively correlated to nest depth only at Garaet Hadj Tahar. Most nests were built in dense tufts of Typha angustifolia and Phragmites australis. The main nesting materials were Phragmites australis and Scirpus maritimus.  相似文献   

10.
中国肉牛分子与基因修饰育种研究进展   总被引:1,自引:0,他引:1  
佟彬  张立  李光鹏 《遗传》2017,39(11):984-1015
随着世界肉牛产业科技的快速发展,我国肉牛产业的整体水平得到明显提高并取得丰硕成果。肉牛育种技术实现了由常规杂交育种向分子标记辅助育种、全基因组选择育种和基因组修饰育种的技术跨越,揭示出大量与生长发育、肉质品质、繁殖与疾病等相关的候选基因与分子标记,并逐步应用于肉牛育种实践。与生长发育性状相关的基因或分子标记主要集中在生长激素基因、生肌调节因子家族、肌肉生长抑制因子和胰岛素样生长因子等;参与肉质形成的基因主要集中在脂肪酸运输与沉积相关信号通路、钙蛋白酶信号通路、生肌调节因子家族与肌肉生长抑制因子等;繁殖性状相关基因或分子标记主要集中在GnRH-FSHR-LH、生长分化因子9、催乳素受体和FoxO1等;抗病相关基因主要有MHC基因家族、TOLL样受体4基因等。目前,利用精准基因编辑技术已培育出促生长发育与提高肉品质的肉牛育种新材料。本文总结了近年来我国在肉牛分子与基因组修饰育种领域取得的研究进展,以期为我国肉牛遗传育种技术研究提供参考和借鉴。  相似文献   

11.
黄鳝的繁殖生态学研究   总被引:5,自引:0,他引:5  
尹绍武  周工健  刘筠 《生态学报》2005,25(3):435-439
以洞庭湖稻区黄鳝为调查研究对象 ,通过野外调查和室内实验系统研究了黄鳝的繁殖生态。对黄鳝的性腺发育周年变化、繁殖行为、自然产卵过程、产卵条件及繁殖洞穴的构造进行了观察和记录 ,产卵室是黄鳝繁殖洞穴特有的构造 ,繁殖洞穴泥土p H平均值为 6 .73± 1.0 12。亲鳝有护卵习性 ,通过对 30尾守洞亲鳝的性腺观察和切片验证 ,守洞鳝多为雄鳝 (占 6 1.3% ) ,少数为兼性偏雄性 (占 38.7% ) ,守洞鳝 1:0 0~ 2 :0 0全在外面活动 ,守洞鳝体长 L (cm)与体重 W (g)回归方程为 :W=1.2 5×10 - 2 L1 .4 2 (r=0 .76 )。人工模拟条件下 ,泡沫组受精卵的平均孵化率 (85 .2 % )极显著地高于对照组 (2 5 .4 % ) (t=8.18,t0 .0 5=2 .4 5 ) ,仔鱼平均成活率 (6 4 .0 % )显著高于对照组 (14 .0 % ) (t=3.73) ,同时对繁殖季节黄鳝为孵卵而所吐的泡沫的作用进行了分析。另外 ,证实了黄鳝产卵的最适放养密度为 2~ 3尾 / m2。为黄鳝的全人工繁殖和半人工繁殖提供了合理化的建议  相似文献   

12.
二十二碳六烯酸(DHA)对维持人体正常的生理功能至关重要,具有极高的生物医学价值。产油微生物是指具有很强的脂肪酸合成能力,DHA占总脂肪酸含量相对较高的一类微生物,是获取DHA的新途径。诱变育种作为一种有效的变异手段在产油微生物选育与改良中显示了极为重要的作用和十分诱人的前景。综述了通过物理和化学诱变选育高产DHA菌株的机理及方法,其中物理诱变包括γ射线、紫外线、离子束和常压室温等离子体等;化学诱变包括甲基磺酸乙酯、亚硝基胍和硫酸二乙酯等;主要介绍了不同诱变育种方式在产油微生物生产DHA研究方面取得的成就,探讨了诱变育种的发展方向,提出了不同诱变育种方式相结合的复合育种的思路,以期对今后产油微生物生产DHA的研究有所启发。  相似文献   

13.
Walsh B 《Genetica》2009,136(2):213-223
The last 20 years since the previous World Congress have seen tremendous advancements in quantitative genetics, in large part due to the advancements in genomics, computation, and statistics. One central theme of this last 20 years has been the exploitation of the vast harvest of molecular markers—examples include QTL and association mapping, marker-assisted selection and introgression, scans for loci under selection, and methods to infer degree of coancestry, population membership, and past demographic history. One consequence of this harvest is that phenotyping, rather than genotyping, is now the bottleneck in molecular quantitative genetics studies. Equally important have been advances in statistics, many developed to effectively use this treasure trove of markers. Computational improvements in statistics, and in particular Markov Chain Monte Carlo (MCMC) methods, have facilitated many of these methods, as have significantly improved computational abilities for mixed models. Indeed, one could argue that mixed models have had at least as great an impact in quantitative genetics as have molecular markers. A final important theme over the past 20 years has been the fusion of population and quantitative genetics, in particular the importance of coalescence theory with its applications for association mapping, scans for loci under selection, and estimation of the demography history of a population. What are the future directions of the field? While obviously important surprises await us, the general trend seems to be moving into higher and higher dimensional traits and, in general, dimensional considerations. We have methods to deal with infinite-dimensional traits indexed by a single variable (such as a trait varying over time), but the future will require us to treat much more complex objects, such as infinite-dimensional traits indexed over several variables and with graphs and dynamical networks. A second important direction is the interfacing of quantitative genetics with physiological and developmental models as a step towards both the gene–phenotype map as well as predicting the effects of environmental changes. The high-dimensional objects we will need to consider almost certainly have most of their variation residing on a lower (likely much lower) dimensional subspace, and how to treat these constraints will be an important area of future research. Conversely, the univariate traits we currently deal with are themselves projections of more complex structures onto a lower dimensional space, and simply treating these as univariate traits can result in serious errors in understanding their selection and biology. As a field, our future is quite bright. We have new tools and techniques, and (most importantly) new talent with an exciting international group of vibrant young investigators who have received their degrees since the last Congress. One cloud for concern, however, has been the replacement at many universities of plant and animal breeders with plant and animal molecular biologists. Molecular tools are now an integral part of breeding, but breeding is not an integral part of molecular biology.  相似文献   

14.
Inbreeding and inbreeding avoidance are key factors in the evolution of animal societies, influencing dispersal and reproductive strategies which can affect relatedness structure and helping behaviours. In cooperative breeding systems, individuals typically avoid inbreeding through reproductive restraint and/or dispersing to breed outside their natal group. However, where groups contain multiple potential mates of varying relatedness, strategies of kin recognition and mate choice may be favoured. Here, we investigate male mate choice and female control of paternity in the banded mongoose (Mungos mungo), a cooperatively breeding mammal where both sexes are often philopatric and mating between relatives is known to occur. We find evidence suggestive of inbreeding depression in banded mongooses, indicating a benefit to avoiding breeding with relatives. Successfully breeding pairs were less related than expected under random mating, which appeared to be driven by both male choice and female control of paternity. Male banded mongooses actively guard females to gain access to mating opportunities, and this guarding behaviour is preferentially directed towards less closely related females. Guard–female relatedness did not affect the guard's probability of gaining reproductive success. However, where mate‐guards are unsuccessful, they lose paternity to males that are less related to the females than themselves. Together, our results suggest that both sexes of banded mongoose use kin discrimination to avoid inbreeding. Although this strategy appears to be rare among cooperative breeders, it may be more prominent in species where relatedness to potential mates is variable, and/or where opportunities for dispersal and mating outside of the group are limited.  相似文献   

15.
Breeding Daphnia magna   总被引:3,自引:3,他引:0  
This paper deals with some methods for breeding Daphnia magna. Critical variables are the filtration of the medium on charcoal, the composition of the medium, the amount of food, the addition of vitamins with yeast extract and the extent of refreshing the medium. If these variables are well controlled, breeding daphnia is easy with reproduction varying from 3 to 9 young per daphnia per day.  相似文献   

16.
ABSTRACT.   Despite being widespread and easily observed, little is known about the life history of Glaucous Gulls ( Larus hyperboreus ). From 1984 to 2007, we examined their breeding biology and demography at Coats Island, Nunavut, Canada, where they nest alongside a colony of 30,000 pairs of Thick-billed Murres ( Uria lomvia ). The gulls fed mainly on murre eggs and chicks and by scavenging adult carcasses. The median age at first breeding was 5 yr, and the mean age was 4.8 ± 0.9 yr. Adult survival was estimated as 0.84 ± 0.03 (SE). The mean clutch size was 2.56 eggs and the mean number of young reared per year was 1.6 (range = 0.9–2.2). Birds reared at the colony provided 40% of recruits. Assuming that survival of locally reared chicks that emigrated was similar to that of chicks that returned to the colony, about 22% of the young gulls survived to breeding age. The timing of breeding by Glaucous Gulls appeared related to the timing of laying by murres. Although the demographic characteristics of Glaucous Gulls in our study were similar to those of populations of other large gulls, adult survival was at the lower end of the range for populations of large Larus gulls. There is some evidence that Glaucous Gulls exhibit lower survival than large gulls breeding in temperate areas, possibly because of contaminant burdens. In general, however, the demographic characteristics of large gulls show little variation and are probably a product of their common phylogeny.  相似文献   

17.
链霉菌育种进展   总被引:2,自引:0,他引:2  
链霉菌是放线菌中最重要的一属,它产生绝大部分抗生素和其它众多活性物质。随着分子生物学的发展,链霉菌育种技术也日益多样。本文从基因突变与育种,遗传重组与育种、基因表达调控与代谢调节育种、基因工程与定向育种等四个方面综述链霉菌育种的进展。  相似文献   

18.
Summary A method is presented to estimate, from a two-factor crossing design including self-fertilization, mean and variance of lines and hybrids that can be derived from a random mating population. The derivation is only valid in the absence of epistasis. From such an estimation, it is possible to derive the expected value of the best lines and of the best hybrids that can be derived from a population.  相似文献   

19.
花卉育种技术研究进展(综述)   总被引:7,自引:0,他引:7  
本文综述近年来国内外花卉育种技术及成果。常规育种仍是花卉育种的主要方法,但日益成熟的生物技术为花卉育种提供了新的途径,尤其是基因工程在改良花卉的色、香、形及延缓衰老等方面将发挥重要作用。  相似文献   

20.
The ability of individuals to leave a current breeding area and select a future one is important, because such decisions can have multiple consequences for individual fitness, but also for metapopulation dynamics, structure, and long‐term persistence through non‐random dispersal patterns. In the wild, many colonial and territorial animal species display informed dispersal strategies, where individuals use information, such as conspecific breeding success gathered during prospecting, to decide whether and where to disperse. Understanding informed dispersal strategies is essential for relating individual behavior to subsequent movements and then determining how emigration and settlement decisions affect individual fitness and demography. Although numerous theoretical studies have explored the eco‐evolutionary dynamics of dispersal, very few have integrated prospecting and public information use in both emigration and settlement phases. Here, we develop an individual‐based model that fills this gap and use it to explore the eco‐evolutionary dynamics of informed dispersal. In a first experiment, in which only prospecting evolves, we demonstrate that selection always favors informed dispersal based on a low number of prospected patches relative to random dispersal or fully informed dispersal, except when individuals fail to discriminate better patches from worse ones. In a second experiment, which allows the concomitant evolution of both emigration probability and prospecting, we show the same prospecting strategy evolving. However, a plastic emigration strategy evolves, where individuals that breed successfully are always philopatric, while failed breeders are more likely to emigrate, especially when conspecific breeding success is low. Embedding information use and prospecting behavior in eco‐evolutionary models will provide new fundamental understanding of informed dispersal and its consequences for spatial population dynamics.  相似文献   

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