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131.
Mutations in MIR396e and MIR396f increase grain size and modulate shoot architecture in rice 总被引:1,自引:0,他引:1
Chunbo Miao Dong Wang Reqing He Shenkui Liu Jian‐Kang Zhu 《Plant biotechnology journal》2020,18(2):491-501
Grain size and plant architecture are critical factors determining crop productivity. Here, we performed gene editing of the MIR396 gene family in rice and found that MIR396e and MIR396f are two important regulators of grain size and plant architecture. mir396ef mutations can increase grain yield by increasing grain size. In addition, mir396ef mutations resulted in an altered plant architecture, with lengthened leaves but shortened internodes, especially the uppermost internode. Our research suggests that mir396ef mutations promote leaf elongation by increasing the level of a gibberellin (GA) precursor, mevalonic acid, which subsequently promotes GA biosynthesis. However, internode elongation in mir396ef mutants appears to be suppressed via reduced CYP96B4 expression but not via the GA pathway. This research provides candidate gene‐editing targets to breed elite rice varieties. 相似文献
132.
Two types of cecidomyiid leaf galls, cup‐shaped and umbrella‐shaped, occur on Litsea acuminata (Lauraceae) in Taiwan. Based on the concept of gall shapes as “extended phenotypes” of gall inducers, these two types could be induced by different gall midge species. However, galls with intermediate shapes between the two types were recently discovered, which implies that possible genetic exchanges occur between the gall inducers of both types. To clarify the taxonomic status of gall midges responsible for the two types of galls on L. acuminata, we undertook taxonomic, molecular phylogenetic and ecological studies. Our findings show that the two gall types are induced by the same Bruggmanniella species and the species is new to science. We describe the species forming this range of galls as Bruggmanniella litseae sp. n. , and compare their geographical distribution, galling position and morphometry. Based on our results, a possible evolutionary scenario of B. litseae sp. n. is discussed. 相似文献
133.
Co‐Co3O4/carbon nanotube/carbon foam (Co‐Co3O4/CNT/CF) nanocomposites were prepared by soaking melamine foam into a solution of Co(NO3)2·6H2O, followed by calcination in N2 and air in sequence. The obtained Co‐Co3O4/CNT/CF nanocomposites were characterized with scanning electron microscopy and cyclic voltammetry. It was found that Co3O4 nanoparticles were grown on the external of CF successfully, while CNTs were grown on the surfaces of CF in a large amount, which further improved the electrical conductivity of the. The prepared Co‐Co3O4/CNT/CF nanocomposites were then used to construct nonenzymatic sensor to detect glucose in alkaline solution. The sensor showed detection range from 1.2 μM to 2.29 mM with a detection limit of 0.4 μM (S/N =3) and a high sensitivity of 637.5 μA?1 cm?2. The developed sensor also showed an instant response, favorable reproducibility, and high selectivity. The results attest that Co‐Co3O4/CNT/CF composites have great potential in the development of nonenzymatic sensors for glucose. 相似文献
134.
135.
旨在研究乙醇对山羊瘤胃液与水稻秸秆厌氧共培养的影响。利用频繁传代的体外发酵技术和高通量测序方法,分析了短链脂肪酸(SCFA)产量和细菌群落的变化。结果表明,经体外培养传代8次的稻秸发酵液的总短链脂肪酸产量显著高于瘤胃液(P<0.01);与未添加乙醇的稻秸发酵液相比,添加乙醇显著提高了乙酸、戊酸和己酸的比例,降低了丙酸和丁酸的比例(P<0.01),总SCFA产量及异丁酸和异戊酸比例无显著差异。与瘤胃液相比,稻秸发酵液的拟杆菌门(Bacteroidetes)相对丰度下降,厚壁菌门(Firmicutes)相对丰度升高(P<0.05),且添加乙醇显著提高了厚壁菌门和放线菌门(Actinobacteria)的相对丰度(P<0.05);添加乙醇使双歧杆菌属(Bifidobacterium)、未定性的毛螺菌属(unidentified Lachnospiraceae)、产琥珀酸菌属(Succiniclasticum)、脱硫弧菌属(Desulfovibrio)和未定性的梭菌属(unidentified Clostridiales)的相对丰度显著升高(P<0.05)。乙醇使稻秸发酵液的显著性差异物种(Biomarker)增加;稻秸发酵液与瘤胃液亲缘关系较近,而添加乙醇显著改变了细菌区系;短链脂肪酸比例在稻秸发酵液细菌群落多样性中具有重要作用。研究表明,体外频繁传代和添加乙醇可以提高稻秸发酵液的乙酸、戊酸和己酸产量,乙醇改变了稻秸发酵液的细菌群落结构。 相似文献
136.
Jialiang Li Richard I. Milne Dafu Ru Jibin Miao Wenjing Tao Lei Zhang Jingjing Xu Jianquan Liu Kangshan Mao 《Molecular ecology》2020,29(7):1250-1266
Having a comprehensive understanding of population structure, genetic differentiation and demographic history is important for the conservation and management of threatened species. High‐throughput sequencing (HTS) provides exciting opportunities to address a wide range of factors for conservation genetics. Here, we generated HTS data and identified 266,884 high‐quality single nucleotide polymorphisms from 82 individuals of Cupressus chengiana, to assess population genomics across the species' full range, comprising the Daduhe River (DDH), Minjiang River (MJR) and Bailongjiang River (BLJ) catchments in western China. admixture , principal components analysis and phylogenetic analyses indicated that each region contains a distinct lineage, with high levels of differentiation between them (DDH, MJR and BLJ lineages). MJR was newly distinguished compared to previous surveys, and evidence including coalescent simulations supported a hybrid origin of MJR during the Quaternary. Each of these three lineages should be recognized as an evolutionarily significant unit (ESU), due to isolation, differing genetic adaptations and different demographic history. Currently, each ESU faces distinct threats, and will require different conservation strategies. Our work shows that population genomic approaches using HTS can reconstruct the complex evolutionary history of threatened species in mountainous regions, and hence inform conservation efforts, and contribute to the understanding of high biodiversity in mountains. 相似文献
137.
通过向设施土壤中添加解磷菌和秸秆,达到活化土壤中作物所需金属元素的含量,促进作物对中微量元素吸收的目的。试验设置对照、秸秆、解磷菌、解磷菌+秸秆4个处理,在不同时间测试土壤及秧苗中钙、镁、铜、铁、锌等的含量,确定解磷菌及秸秆对设施土壤金属元素含量及黄瓜秧苗吸收量的影响。试验结果表明,秸秆、解磷菌、秸秆+解磷菌处理能明显增加黄瓜秧苗吸收钙、镁、铁、铜的能力,对锌的吸收没有影响,其中秸秆+解磷菌处理对黄瓜秧苗吸收钙、镁、铜影响最大,促进作用分别达到6.26%、8.25%和11.57%,3种处理对设施土壤中有效钙、镁、铁的含量没有影响,但是能明显提高土壤中有效铜、锌的含量,盛果后期有效铜含量分别比对照提高12.19%、15.41%、16.49%,盛果后期有效锌含量分别比对照区提高38.8%、33.26%、56.81%。 相似文献
138.
为了更好地分离珠江口未/难培养的浮游细菌,本研究以珠江河口三个样点的水体为研究对象,同时采用了纯培养和免培养的方法,对不同培养基的分离效果进行了探索。在纯培养实验中,本研究选择了7种不同的分离培养基,共分离获得153株菌;同时,将扩增子分析结果作为分离效果的参考,所有环境样品中共包含3 553个操作分类单元(operational taxonomic units,OTUs)。对三个样点微生物类群的多样性进行比较,纯培养结果显示珠江口下游珠海样点多样性最高,其次为中大和虎门样点;免培养则显示虎门样点多样性最高;对比7种不同的分离培养基,Z7(R2A)培养基的分离效果最好,分离菌株数和分离类群的α多样性最高,Z1(改良ISP 2)次之;主坐标分析结合韦恩图的结果表明相比其余的培养基,Z1和Z7培养基分离获得的菌群兼具普遍性和特异性,进一步证明了这两种培养基的分离效果较佳;冗余分析结果表明K2HPO4、酵母粉、可溶性淀粉、MgSO4·7H2O、麦芽膏和葡萄糖与特定类群的分离有相关关系,其中K2HPO4的影响最为显著(P<0.05)。本文通过7种不同培养基对河口微生物分离效果的探究,有助于我们在研究未知微生物的营养特性时,选择成分和组成更合理的培养基来提升河口微生物纯培养的分离效率。 相似文献
139.
Kopruszinski Caroline M. Swiokla Juliana Lee Yeon Sun Navratilova Edita VanderVeen Laurie Yang Miao Liu Yi Miyazaki Takahiro Schmidt William K. Zalevsky Jonathan Porreca Frank 《Cellular and molecular neurobiology》2021,41(5):949-960
Cellular and Molecular Neurobiology - Pharmacological evaluation of the mu-opioid receptor (MOR) agonist properties of NKTR-181 in rodent models. Graded noxious stimulus intensities were used in... 相似文献