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61.
62.
Yan-Hong He Guo-Gui Ning Ya-Lin Sun Yan Hu Xing-Yu Zhao Man-Zhu Bao 《Molecular breeding : new strategies in plant improvement》2010,26(1):19-29
A male sterile line was isolated in marigold (Tagetes erecta L.) and cytological analysis determined this to be a novel genic male sterility trait (Tems). Through the use of amplified fragment length polymorphisms (AFLPs) and bulked segregant analysis (BSA), tightly linked
markers of Tems were identified with a view towards a map-based cloning strategy. It was found that spontaneous homeotic conversion of floral
organs was the underlying cause of the male sterility in this marigold line. Thus, petals of male sterile plants resembled
sepal-like structures and the stamens were partially converted to styles, although without the full characteristics or function
of the true style organs. We have constructed a fine marker-based map for the Tems gene. This is intended to provide a tool for marker assisted selection (MAS) strategies in hybrid breeding and map-based
cloning strategies for the male sterility locus. We discuss the significance of this spontaneously derived genic male sterility
trait relating to the homeotic conversion of floral organs in marigold. 相似文献
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64.
Abstract All ants (Hymenoptera, Formicidae) are highly eusocial insects that are characterized by reproductive division of labor with sterile castes (worker and soldier) helping fertile castes (queen and male) to reproduce.
Ant societies, like other complex animal societies, have developed a sophisticated communication system, in which recognition behaviors are frequently involved Recognition abilities allow individuals to orient and modulate their behaviors effectively and appropriately in response to the characteristics andlor signals expressed by other organisms. Among recognition behaviors, nestmate recognition and kin recognition mechanisms have attracted great attention of sociobiologists, ecologists, insect physiologists and biochemists since 1970's. This is parallel with the popularization of Hamilton's kin selection theory. The present paper aims at reviewing the current understanding on nestmate/kin recognition in ants. This review consists of three parts. The first part concerns the diversity of recognition behaviors and their ecological implications with emphasis on nestmatelkin recognition; in the second part, the current understandings on the mechanism of nestmatelkin recognition are outlined; and in the third part, we discuss the ontogenetic development of nestmate recognition behavior and naturally mixed colonies. The study of the integration mechanism of social parasite may provide heuristic clues to the understanding of kin/nestmate recognition system. 相似文献
Ant societies, like other complex animal societies, have developed a sophisticated communication system, in which recognition behaviors are frequently involved Recognition abilities allow individuals to orient and modulate their behaviors effectively and appropriately in response to the characteristics andlor signals expressed by other organisms. Among recognition behaviors, nestmate recognition and kin recognition mechanisms have attracted great attention of sociobiologists, ecologists, insect physiologists and biochemists since 1970's. This is parallel with the popularization of Hamilton's kin selection theory. The present paper aims at reviewing the current understanding on nestmate/kin recognition in ants. This review consists of three parts. The first part concerns the diversity of recognition behaviors and their ecological implications with emphasis on nestmatelkin recognition; in the second part, the current understandings on the mechanism of nestmatelkin recognition are outlined; and in the third part, we discuss the ontogenetic development of nestmate recognition behavior and naturally mixed colonies. The study of the integration mechanism of social parasite may provide heuristic clues to the understanding of kin/nestmate recognition system. 相似文献
65.
Abstract In this paper, we reported the differences in susceptibility to insecticides between adults and larvae of housefly, Musca domestica (L.), and the mechanisms for the differences. The larvae of housefly were much more tolerant to insecticides than the adults, and the tolerance ratio to cyhalothrin was as high as 205.5 for susceptible strain. Mechanism studies showed that higher GST activity was associated with higher insecticide tolerance in the larvae. The co-toxicity coefficient of the mixture of cyhalothrin and methylene dithiocyanate(4:1) on pyrehid-resistant houseflies was 188. 相似文献
66.
Abstract Rheocricotopus (Psilocricotopus) taiwanensis sp. n. from Taiwan, China, is described as male imagines. The species is allied to R. (P.) chalybeatus (Edwards) but it is easily separated from the latter in lacking setae in all reins, much lower AR and more pronounced crista dorsalis in gonostylus. The genus is new to Taiwan Province, China. The specimen is deposited at the Department of Biology, Nankai University, Tianjin. 相似文献
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68.
Yan Yongshan Fen Shang Liu Lianrui 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,74(1):147-153
Summary A 8.3 /ml 6-thioguanine (6TG)-resistant strain was isolated from a rat tetraploid cell line by step-by-step selection in 6TG-medium. In the 6TG-resistant cell population 51% of the cells were tetraploid and 35% of the cells were hypertetraploid, i.e., one chromosome more than a tetraploid. The 6TG-resistant strain grew very well in RPMI 1640 medium with intervals of three days between subcultures. The 6TG-resistant cells all have a homogeneously staining region (HSRs) in one of the X chromosomes which do not stain after chromosome C-banding. They also possess a higher NORs activity and much lower frequency of sister chromatid exchanges (SCE). When the 6TG-resistant RCT cells were subcultured in 6TG-free medium for three days, their SCE frequency did not change. 5-bromodeoxyuridine (BrdU) significantly suppressed the NORs activity for both 6TG-resistant cells and 6TG-sensitive cells (P<0.001).Abbreviations 6TG
6-thioguanine
- HSRs
homogeneously staining region
- NORs
nucleolar organizer region
- SCE
sister chromatid exchange
- BrdU
5-bromodeoxyuridine
- HPRT
Hypoxanthine phosphoribosyl transferase 相似文献
69.
电刺激大鼠尾核头部对丘脑腹后外侧核痛相关神经元电活动的影响 总被引:1,自引:0,他引:1
丘脑腹后外侧核的神经元对伤害性刺激的反应形式主要为以下三种类型:痛兴奋神经元、痛抑制神经元和痛无关神经元。痛相关神经元的放电活动可被吗啡类药物所抑制。电刺激尾核头部对痛相关神经元主要产生抑制作用,尾核头部背侧的作用强于腹侧,且受不同刺激参数的影响。本文就以上结果在镇痛中的意义进行了讨论。 相似文献
70.