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To explore the physiological characteristics of the pepc gene in transgenic wheat (Triticum aestivum) plants, PEPC activities in various organs of T3 plants were analyzed at Feekes 6.0, Feekes 10.3 and Feekes 11.1, and compared to control, untransformed wheat cultivar Zhoumai 19. Net photosynthetic rates (P n) in leaves were also measured at the same stages. At Feekes 11.1, both transgenic and control plants were treated with DCDP. Yield traits were surveyed after harvest. The results indicated that P n and PEPC activity in the flag leaf of transgenic wheat were significantly higher than those of the control at different stages. At Feekes 10.3, P n reached the highest value at 28.2 μmol m−2 s−1 and PEPC activity reached the highest value at 104.6 μmol h−1 mg−1. Both factors significantly increased by 21% compared to the control at Feekes 11.1. PEPC activity in the flag leaf of transgenic plants was significantly higher than that of non-leaf organs. P n of transgenic plants was greatly reduced after DCDP treatment. In the flag leaf of transgenic wheat, P n was significantly correlated to PEPC activities at 0.01 probability level with a correlation coefficient of 0.8957**. The yield traits of transgenic line 1-27-3, such as 1000-grain weight, single spike weight and harvest index were higher than those of the control. Additionally, the spike weight of 1-27-3 showed an increase of approximately 9.5% compared to the control. These results indicated that the expression of maize (Zea mays) pepc gene was different across various organs of transgenic wheat and across every growth stage. Therefore, we conclude that introducing maize pepc gene into wheat plants can increase their P n and improve production.
Stripe rust, caused by Puccinia striiformis Westend. f. sp. tritici Eriks., is a major disease that causes substantial losses to wheat production worldwide. The utilization of effective resistance genes in wheat cultivars is the preferred control of the disease. To study the inheritance of all-stage resistance in spring wheat cultivars Louise, WA008016, Express, Solano, Alturas and Zak from the Pacific Northwest (PNW) of the United States, the six cultivars were crossed with the Chinese susceptible variety Taichung 29. Single-spore isolates of CYR32 and CYR33, the predominant Chinese races of P. striiformis f. sp. tritici, were used to evaluate F1, F2 and BC1 generations for stripe rust resistance under controlled greenhouse conditions. Genetic analysis determined that Louise had one dominant resistance gene to CYR32, temporarily designated as YrLou. WA008016 had two dominant and one recessive resistance genes to CYR32, temporarily designated as YrWA1, YrWA2 and YrWA3, respectively. Express had a single recessive gene that conferred resistance to CYR32, temporarily designated as YrExp3. The two independent dominant genes in Solano conferring resistance to CYR32 were temporarily designated as YrSol1 and YrSol2. Alturas had two recessive genes for resistance to CYR32, temporarily designated as YrAlt1 and YrAlt2. Zak has one dominant gene for resistance to CYR33, temporarily designated as YrZak1. These six cultivars can be important resistance sources in Chinese wheat stripe rust resistance breeding.
Thinopyrum intermedium, which has many useful traits, is valuable for wheat breeding. A new wheat-Thinopyrum addition line, SN100109, was developed from the progeny of common wheat cultivar Yannong 15 and Th. intermedium. It was resistant to most races of Blumeria graminis f. sp tritici (Bgt), which caused powdery mildew in wheat, and its reactions were different from the reactions of gene Pm40 and Pm43. Genomic in situ hybridization (GISH) and molecular marker analysis were used to identify the genomic composition of SN100109. GISH results showed that SN100109 was a wheat-Th. intermedium disomic addition line containing one pair of J chromosomes, and the resistance gene was located on the alien additional chromosomes of SN100109. And four molecular markers BE425942, BF482714, Xgdm93 and BV679214 which were assigned to homologous group 2, were specific molecular markers of the additional chromosomes. All the results indicated that SN100109 contained one pair of 2J chromosomes. SN100109 can be used as a novel germplasm source for introducing powdery mildew resistance genes to wheat in breeding programs.
High-yield common buckwheat ‘cv. Fengtian 1’ (FT1) and tartary buckwheat ‘cv. Jingqiao 2’ (JQ2) were selected to investigate the characteristics of the grain-filling process and starch accumulation of high-yield buckwheat. FT1 had an average yield that was 43.0% higher than that of the control ‘cv. Tongliaobendixiaoli’ (TLBDXL) in two growing seasons, while JQ2 had an average yield that was 27.3% higher than that of the control ‘cv. Chuanqiao 2’ (CQ2). The Richards equation was utilized to evaluate the grain-filling process of buckwheat. Both FT1 and JQ2 showed higher values of initial growth power and final grain weight and longer linear increase phase, compared with respective control. These values suggest that the higher initial increasing rate and the longer active growth period during grain filling play important roles to increase buckwheat yield. Similar patterns of starch, amylose and amylopectin accumulation were detected in common buckwheat, leading to similar concentration of each constituent at maturity in FT1 and TLBDXL. Tartary buckwheat showed an increasing accumulation pattern of amylose in developing seeds, which differed from that of starch and amylopectin. This pattern led to a significant difference of the concentrations of amylose and amylopectin at maturity between JQ2 and CQ2, the mechanisms of which remained unclear. Nevertheless, both FT1 and JQ2 showed increased starch, amylose, and amylopectin accumulation during the physiological maturity of grains. The results suggest that prolonging the active grain-filling period to increase carbohydrate partitioning from source to seed sink can be an effective strategy to improve buckwheat yield.
It is well demonstrated that wheat-rye 1BL/1RS translocated chromosome leads to some valuable novel traits such as disease resistance, high yield and functional stay-green after anthesis. To understand the physiological mechanism of 1BL/1RS translocation responsible for osmotic stress, two wheat cultivars, CN12 and CN17, carrying the translocated chromosome and MY11 without the translocated chromosome were employed in the study. During 5-day osmotic stress, fresh weight inhibition, chlorophyll content, soluble protein content, MDA concentration, antioxidant enzymes activity and free polyamines content were examined. CN12 and CN17, especially cultivar CN17, registered greater biomass and minor oxidative damage compared with their wheat parent. Meanwhile, the concentration of Spd and Spm in CN17 was significantly higher than the others. In addition, we found a positive correlation of fresh weight inhibition (FWI) and Put concentration, and a negative one with the parameters (Spd + Spm): Put ratio, indicating the importance of higher polyamine (Spd and Spm) accumulation on the adaptation to osmotic stress. Therefore, we proposed that the accumulation of higher polyamines (Spd and Spm) should play an important role on the adaptation of 1BL/1RS translocation lines to osmotic stress and might be important factors for the origin of novel traits introduced by 1BL/1RS.
Abstract
This work used a carrageenan-based thrombosis model to determine the preventative effects of Lactobacillus plantarum YS1 (LPYS1) on thrombus. In thrombotic mice, LPYS1 improved the activated partial thromboplastin time (APTT), while decreasing the thrombin time (TT), prothrombin time (PT), and fibrinogen (FIB) content. In thrombotic mouse serum, LPYS1 decreased the levels of malondialdehyde (MDA), tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), nuclear factor kappa-B (NF-κB), and interleukin-1 beta (IL-1β), while also increasing the activities of superoxide dismutase (SOD) and catalase (CAT). Moreover, LPYS1 upregulated the mRNA expression levels of copper/zinc-SOD (Cu/Zn-SOD), manganese-SOD (Mn-SOD), and CAT in the colon tissues of thrombotic mice, while downregulating those of NF-κB p65, IL-6, TNF-α, and interferon-gamma (IFN-γ) mRNA. In tail vein vascular tissues, LPYS1 suppressed the mRNA expression levels of NF-κB p65, intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin. The abundances of both beneficial and pathogenic bacteria were altered by LPYS1. These findings show that LPYS1 has the capacity to protect mice from thrombosis, while also revealing some of the underlying mechanisms of this effect.
Abstract
As research advances, it is generally acknowledged that non-Saccharomyces yeast contribute to the addition of aromatic compounds during mead fermentation. In this experiment, eight different non-Saccharomyces strains and Saccharomyces cerevisiae co-fermentation, their aroma composition, and basic physicochemical parameters were investigated. More than 30 compounds with favourable impact were discovered using solid-phase microextraction (SPME) coupled to gas chromatography-mass spectrometry (GC-MS). Co-fermentation of non-Saccharomyces spp. and S. cerevisiae can affect the concentration of volatile compounds, so that the mead presents different aroma characteristics. Co-fermented meads of Wickerhamomyces anomalus strains and S. cerevisiae (Wa 27-Sc and Wa 5-Sc) had higher alcohol, acids, aldehyde, and ester concentrations than those fermented with S. cerevisiae alone. In terms of taste, Wa 27-Sc was superior to Wa 5-Sc. Overall, the Wa 27-Sc received the highest score for its strong secondary aroma and good mouthfeel. The results show that the W. anomalus Wa 27 strain has a good potential to produce high quality mead.
A method was developed for the preparative separation of two alkaloids from the crude extract of the radix of Rauvolfia verticillata (Lour.) Baill. in a single run. The two-phase solvent system composed of petroleum ether–ethyl acetate–methanol–water (5:5:2:8, v/v), where triethylamine (40 mmol/L) was added to the upper organic phase as the stationary phase and hydrochloric acid (10 mmol/L) was added to the lower aqueous phase as the mobile phase, was selected for this separation by pH-zone-refining counter-current chromatography (PZRCCC). For the preparative separation, the apparatus was rotated at a speed 850 rpm, while the mobile phase was pumped into the column at 2 mL/min. As a result, 112 mg of reserpine and 21 mg of yohimbine were obtained from 3 g of crude extract in a single run. The analysis of the isolated compounds was determined by high-performance liquid chromatography (HPLC) at 230 nm with purities of over 91.0%, and the chemical identification was carried out by the data of electrospray ionization–mass spectrometry (ESI–MS) and nuclear magnetic resonance (NMR) spectroscopy. The technique introduced in this paper is an efficient method for preparative separation of reserpine and yohimbine from devil pepper radix. It will be beneficial to utilize medicinal materials and also useful for the separation, purification, and pharmacological study of Chinese herbal ingredients.
Summary
Accelerator mass spectrometry (AMS) is an ultra-sensitive method to monitor and trace the environmental exposure levels of 14C-labeled molecules in vivo. Nicotine [3-(1-methyl-2-pyrrolidinyl)-pyridine], a major alkaloid in tobacco products, has proven to be a potential genotoxic compound. Using 14C-labeled nicotine and AMS, we have investigated the inhibitory effect of curcumin, garlic squeeze, grapeseed extract, tea polyphenols, vitamin C and vitamin E, respectively, on nicotine-hemoglobin (Hb) adduction in vivo. The results demonstrated that these dietary constituents induced remarkable decrease of nicotine-Hb adducts. The inhibitory fact may afford an important clue of the chemoprevention of the potential nicotine-induced carcinogenesis.
Studies of the pollen abortion mechanism in thermo-sensitive male sterile lines may provide a strong foundation for breeding hybrid wheat and establishing a theoretical basis for marker-assisted selection. To investigate the cause of pollen abortion in Bainong thermo – sensitive male sterile (BNS) lines, we analyzed the properties of pollen grains, changes in the tapetum and microspores in different anther developmental stages, and the distribution and deposition of nutrient substances in microspores. We found that tapetum degraded in the early uninucleate stage in sterile BNS (S-BNS), which was earlier than that of fertile BNS (F-BNS) tapetum. Large amounts of insoluble polysaccharides, lipids, and proteins were deposited until the trinucleate pollen stage in the nutritive cells in F-BNS. At the binucleate stage, the vacuoles disappeared and pollen inclusion increased gradually. At the trinucleate stage, these nutrients would help pollen grains mature and participate in fertilization normally. Therefore, early degradation of the tapetum, which inhibits normal microspore development, and the limited content of nutrient substances in pollen may be the main factors responsible for male sterility in BNS lines.
