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721.
YOUNG-OK KIM SUN YOUNG KIM WOO-JIN LEE JOONG KI CHOI 《The Journal of eukaryotic microbiology》2010,57(1):48-55
ABSTRACT. A choreotrich ciliate collected in waters off Geoje Island, on the eastern coast of the South Sea of the southern coastal water of Korea was morphologically and biometrically investigated through observations of permanent preparations after protargol impregnations. Morphological data and ciliary patterns indicated that the ciliate should be identified as Strombidinopsis acuminata based on the number of somatic kineties. The vertical distribution of the population abundance was also examined in relation to environmental conditions: higher abundances occurred in surface water with higher temperature (22–23 °C), lower salinity (32 psu), and higher concentration (ca 10 μg/L) of chlorophyll a . The 18S rRNA gene of specimens from clonal cultures isolated from natural assemblages was sequenced. While this isolate of S. acuminata is closer to Strombidinopsis jeokjo (99.6–99.8%) than other isolates of S. acuminata (<99.0%), monophyly of S. acuminata was not rejected by the AU test. We discuss the discordance between morphological and molecular data for Strombidinopsis . In order to confirm the species level of the Strombidinopsis specimens, additional information is required based on genealogical analyses of multiple loci. 相似文献
722.
为创制棉花耐旱种质资源,解决棉花耐旱资源贫乏以及提高水资源利用率,研究依据CRISPR/Cas9编辑原理,对课题组前期利用RT-PCR技术筛选耐旱相关基因GhNAC3(Gh_D02G0790)的第一外显子区域设计2个20 bp的编辑靶点,并在陆地棉基因组数据库中比对分析靶点序列,排除非特异性编辑,将2个靶点核苷酸片段分别与gRNA-AtU6载体连接,通过2次PCR扩增,得到含特异性连接接头的AtU6-GhNAC3表达盒,再将表达盒连接到CRISPR/Cas9(pRGEB32-7)载体上,获得CRISPR-GhNAC3重组表达载体,利用农杆菌介导法转化陆地棉受体YZ-1,再生培养得到T0代转基因幼苗,通过PCR检测Cas9蛋白基因获得阳性株系。对T0代植株的靶点区域序列进行PCR扩增和测序分析,鉴定GhNAC3编辑类型。结果发现,CRISPR9-GhNAC3表达载体成功转化YZ-1,并获得40株转基因再生植株,经Cas9蛋白基因鉴定得到30株阳性株系,从阳性植株选择10株进行编辑类型测序分析,发现7株在靶点区域发生编辑,编辑类型主要为碱基片段缺... 相似文献
723.
D. W. LEE YAP KIM PIN LIEW FOO YEW 《Botanical journal of the Linnean Society. Linnean Society of London》1975,70(1):77-81
Serological comparisons of the seed proteins of Flagellaria indica L., Joinvillea bomeensis Becc. and Hanguana malayanum Merr. were made in order to provide evidence for the systematic evaluation of these taxa. Lack of serological cross-reactivity suggests the placement of these genera in three separate monogeneric families, Flagellariaceae, Joinvilleaceae and Hanguanaceae. Additional serological analyses are needed to evaluate their systematic position in the monocotyledons. 相似文献
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CHARLES FOX KIM WADDELL JAMES DES LAURIES TIMOTHY MOUSSEAU 《Ecological Entomology》1997,22(4):416-424
1. Although numerous studies have examined the ecology of plant resistance to herbivores and the distribution of herbivores within plant hybrid zones, few have examined how plant hybridization influences herbivore growth, development, or life history. The experiment reported here examines variation in survivorship, development time, and final adult body size of Stator limbatus reared on seeds of parental and hybrid Cercidium floridum-×-C. microphyllum trees from a paloverde hybrid zone in eastern California. Because S. limbatus exhibits egg size plasticity in response to host species, the size of eggs that females lay on hybrid and parental plants is also examined. 2. The hypotheses (a) that seeds of hybrid trees are intermediate between those of the two parental species in their resistance to penetration by S. limbatus larvae; (b) that seeds of hybrid trees are intermediate in their suitability for the growth of larvae that successfully penetrate the seed-coat; (c) that female S. limbatus can distinguish between hybrid trees and pure-bred trees, as quantified by the size of eggs they lay on seeds of each taxon, and (d) that female S. limbatus can distinguish among individual hybrid trees, are tested. 3. On average, S. limbatus survivorship was lower, development time longer, and emergence body mass lower on seeds of C. floridum than on seeds of C. microphyllum. Seeds of hybrid trees were, on average (across trees), intermediate between seeds of the parental species in the resistance of their seed-coats to penetration by S. limbatus larvae and in their suitability for larval growth. Individual hybrid trees also varied in the resistance of their seeds to, and the suitability of their seeds for, S. limbatus larvae. 4. Female S. limbatus laid significantly larger eggs on seeds of C. floridum than on seeds of C. microphyllum, and, on average, intermediate size eggs on hybrid trees. The size of eggs laid by females also varied among hybrid trees, with females laying C. floridum-sized eggs on some trees, and C. microphyllum-sized eggs on other trees. These results suggest that females have at least some ability to distinguish among hybrid trees, but there was no evidence that females laid larger eggs on poorer quality hybrid trees. 相似文献
727.
Abstract. Face flies overwinter as adults in reproductive diapause. Administration of 20-hyroxyecdysone and/or methoprene induced reproductive development in diapausing flies which were maintained in a diapause-inducing environment. Hormone effects were additive and female flies were more sensitive than males. Release of vitellogenin from cultured fat body was stimulated by 20-hydroxyecdysone or methoprene. Transfer of flies from diapause to diapause-breaking environments induced some to break diapause, but this decreased with the time flies had been in a diapause-inducing environment. In contrast, topical application of methoprene to diapausing flies induced reproductive development irrespective of their ages even when they were kept in the diapause-inducing environment for 80 day degrees above a 12°C base temperature (14.5 days). Therefore diapause induction must depend on hormone levels less than some threshold level. The putative threshold varied according to diapause propensities of different genetic lines. Lines showing high frequencies of diapause required greater amounts of methoprene for reproductive development in diapause conditions than did lines showing low frequencies of diapause. 相似文献