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971.
《Animal : an international journal of animal bioscience》2013,7(12):1925-1934
Two in vitro and one in vivo experiments were conducted to investigate the effects of a selection of plant compounds on rumen fermentation, microbial concentration and methane emissions in goats. Treatments were: control (no additive), carvacrol (CAR), cinnamaldehyde (CIN), eugenol (EUG), propyl propane thiosulfinate (PTS), propyl propane thiosulfonate (PTSO), diallyl disulfide (DDS), a mixture (40 : 60) of PTS and PTSO (PTS+PTSO), and bromochloromethane (BCM) as positive control with proven antimethanogenic effectiveness. Four doses (40, 80, 160 and 320 µl/l) of the different compounds were incubated in vitro for 24 h in diluted rumen fluid from goats using two diets differing in starch and protein source within the concentrate (Experiment 1).The total gas production was linearly decreased (P<0.012) by all compounds, with the exception of EUG and PTS+PTSO (P⩾0.366). Total volatile fatty-acid (VFA) concentration decreased (P⩽0.018) only with PTS, PTSO and CAR, whereas the acetate:propionate ratio decreased (P⩽0.002) with PTS, PTSO and BCM, and a tendency (P=0.064) was observed for DDS. On the basis of results from Experiment 1, two doses of PTS, CAR, CIN, BCM (160 and 320 µl/l), PTSO (40 and 160 µl/l) and DDS (80 and 320 µl/l) were further tested in vitro for 72 h (Experiment 2). The gas production kinetics were affected (P⩽0.045) by all compounds, and digested NDF (DNDF) after 72 h of incubation was only linearly decreased (P⩽0.004) by CAR and PTS. The addition of all compounds linearly decreased (P⩽0.009) methane production, although the greatest reductions were observed for PTS (up to 96%), DDS (62%) and BCM (95%). No diet–dose interaction was observed. To further test the results obtained in vitro, two groups of 16 adult non-pregnant goats were used to study in vivo the effect of adding PTS (50, 100 and 200 mg/l rumen content per day) and BCM (50, 100 and 160 mg/l rumen content per day) during the 9 days on methane emissions (Experiment 3). The addition of PTS and BCM resulted in linear reductions (33% and 64%, respectively, P⩽0.002) of methane production per unit of dry matter intake, which were lower than the maximum inhibition observed in vitro (87% and 96%, respectively). We conclude that applying the same doses in vivo as in vitro resulted in a proportional lower extent of methane decrease, and that PTS at 200 mg/l rumen content per day has the potential to reduce methane emissions in goats. Whether the reduction in methane emission observed in vivo persists over longer periods of treatments and improves feed conversion efficiency requires further research. 相似文献
972.
Jie Li Yu Han Ting‐Ru Jiang Jia Liu Hong‐Xia Hua Yan‐Fei Xiong Jun‐Sheng Li 《Insect Science》2013,20(6):703-716
The brown planthopper (BPH) Nilaparvata lugens is an economically important pest on rice plants. In this study, the higher population density and yellow‐ripe stage of rice plants were used to construct adverse survival conditions (ASC) against BPH nymphs. Simultaneously, the low population density and tillering stage of rice plants were used to establish a suitable survival condition (SSC) as a control. Solexa/Illumina sequencing was used to identify genes of BPH nymphs responding to ASC. Significantly longer duration development of BPH nymphs and significantly lower brachypterous ratio of BPH adults were observed by ASC compared with SSC. A total of 2 544 differentially expressed genes (DEGs) were obtained and analyzed by BLASTx, Gene Ontology and KEGG Orthology. Gene ontology analysis revealed that the DEGs were mainly involved in categories of cell, cell part, cellular process, binding, catalytic, organelle and metabolic processes. 1 138 DEGs having enzyme commission numbers were assigned to different metabolic pathways. The largest clusters were neurodegenerative diseases (137, 12.0%), followed by carbohydrate metabolism (113, 9.9%), amino acid metabolism (94, 8.3%), nucleotide metabolism (76, 6.7%), energy metabolism (64, 5.6%), translation (60, 5.3%), lipid metabolism (58, 5.1%), and folding, sorting and degradation (52, 4.6%). Expressing profile of 11 DEGs during eight nymphal developmental stages of BPH were analyzed by quantitative real‐time polymerase chain reaction. The 11 genes exhibited differential expression between ASC and SSC during at least one developmental stage. The DEGs identified in this study provide molecular proof of how BPH reconfigures its gene expression profile to adapt to overcrowding and low‐quality hosts. 相似文献
973.
974.
975.
976.
气体植物激素乙烯在植物生长发育及应对胁迫的防御反应中起重要调控作用.通过20多年的研究,利用模式植物拟南芥,勾画出一条自内质网膜受体至细胞核内转录因子的线性乙烯信号转导通路.本文概述了研究乙烯信号转导的方法及乙烯信号转导的基本过程;阐述了最新发现的乙烯信号从内质网膜传递到细胞核的分子机制,即原本定位于内质网膜上的EIN2蛋白其C端被剪切之后进入细胞核,然后通过抑制EBF1/2而稳定转录因子EIN3/EIL1;根据最近多个小组报道EIN3/EIL1直接调控除乙烯响应基因之外的其他生物学过程相关基因,提出了EIN3/EIL1可以作为网络节点整合多条信号通路的新观点;通过分析不同信号通路调控EIN3/EIL1的方式,发现不仅EIN3/EIL1的蛋白稳定性受到调控,而且其转录活性还受到诸如JAZ,DELLA等转录调节因子的调控.本文展望了未来乙烯信号转导通路的研究方向与研究热点. 相似文献
977.
细胞与细胞之间的物质运输和信号传递对于多细胞生物的生长发育非常重要.一些内源的大分子物质如蛋白质、核酸或核酸蛋白质复合体可以选择性地通过植物特有的亚细胞结构即胞间连丝(PD)在细胞之间运输.小分子物质主要以被动的形式在细胞间通过PD进行扩散.PD对蛋白质和核酸的运输具有选择性,这种运输受到严格调控.大分子物质在细胞间的运输对植物的生长和发育有极其重要的调控作用.KN1,STM,SHR,TRY和WER等转录因子在细胞之间的转运对于维持植物的茎尖分生组织、根尖分生组织和表皮细胞功能起重要作用.另外,某些小分子RNA也能够在植物细胞间进行选择性运输,并通过在不同细胞中降解或抑制靶mRNA的翻译来调节植物组织的生长发育. 相似文献
978.
P. Gurusaravanan S. Vinoth M. Satheesh Kumar N. Thajuddin N. Jayabalan 《Journal of Genetic Engineering and Biotechnology》2013,11(1):9-16
The challenging task of bringing high efficiency transformed plants attracts lot of attention in recent times. In search for this, there have been many attempts made using, different techniques like tissue culture and plant breeding methods. Here we report a suitable alternative facile route, where cyanobacterial extracellular products are utilized as growth regulators and its performance validated on Gossypium hirsutum L. MS medium is tested with cyanobacterial extracellular products of Nostoc ellipsosporum, Dolichospermum flos-aquae and Oscillatoria acuminata .Our best results show that the addition of O. acuminata extracellular product with plant growth hormones gives the excellent induction and elongation in cotton. In addition to this, the multiple shoot was obtained on MS medium fortified with 1.0 mg L?1 BA with 8% O. acuminata and 1.5 mg L?1 TDZ with 12% O. acuminata. High frequency of shoot elongation supplemented with MS medium, iP 2.5 mg L?1 and 16% O. acuminata and root production MS medium fortified with 12% O. acuminata best responsible for regeneration in cotton plants. The rooted plants were hardened and transferred to soil with 90% survival rate. 相似文献
979.
《Journal of Plant Interactions》2013,8(4):255-262
Abstract Induction of resistance to downy mildew caused by Plasmopara halstedii in sunflower was studied after treatment with PGPR (plant growth promoting rhizobacteria) strain INR7 (Bacillus spp). Treatment of sunflower seeds with 1×108cfu/ml of PGPR strain INR7 resulted in decreased disease severity and offered 51 and 54% protection under green house and field conditions, respectively. The induction of resistance to P. halstedii by PGPR strain INR7 was accompanied by the accumulation of various host defense-related enzymes in susceptible sunflower seedlings. Enhanced activation of catalase (CAT), phenylalanine ammonia-lyase (PAL), peroxidase (POX), polyphenol oxidase (PPO) and chitinase (CHI) was evident at 6, 9, 12, 12 and 12h post inoculation, respectively, in sunflower seedlings raised from seeds treated with PGPR strain INR7. This enhanced and early activation of defense-related responses in the susceptible cultivar after treatment with PGPR strain INR7 was comparable to that in the resistant cultivar. The results indicate that PGPR strain INR7 induced resistance against P. halstedii in sunflower is mediated through enhanced expression of defense mechanism. 相似文献
980.
《Archives of animal nutrition》2013,67(1):66-74
The study was conducted to evaluate the effects of dietary supplementation with different levels of two extracts, an aqueous extract of Ligustrum lucidum (AELL), and an ethanol extract of Schisandra chinensis (EESC) on growth performance, parameters of antioxidative status and spleen lymphocyte proliferation of broilers, respectively. The results showed that neither AELL nor EESC had significant effects on growth performance of broilers. However, malondialdehyde concentration in heart and liver of the broilers were significantly decreased by feeding AELL or EESC. Superoxide dismutase activity in heart, liver, and kidney of broilers were improved by feeding different dosages of AELL or EESC. In contrast, glutathione reductase activity in serum, heart and kidney of broilers was not affected by experimental treatment. In addition, spleen lymphocyte proliferation of broilers was significantly enhanced by feeding different dosages of AELL or EESC. In conclusion, the results suggested that either AELL or EESC may improve antioxidant status and immune function of broilers. 相似文献