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Global rice supplies have been found contaminated with unapproved varieties of genetically modified (GM) rice in recent years, which has led to product recalls in several of countries. Faster and more effective detection of GM contamination can prevent adulterated food, feed and seed from being consumed and grown, minimize the potential environmental, health or economic damage. In this study, a simple, reliable and cost-effective multiplex polymerase chain reaction (PCR) assay for identifying genetic modifications of TT51-1, Kemingdao1 (KMD1) and Kefeng6 (KF6) rice was developed by using the event-specific fragment. The limit of detection (LOD) for each event in the multiplex PCR is approximately 0.1%. Developed multiplex PCR assays can provide a rapid and simultaneous detection of GM rice.
The forward and reverse cDNA subtractive libraries before and after the toxic effect of α-amanitin were constructed by suppression subtractive hybridization and randomly selected clones from each subtractive library were screened by PCR and dot blot hybridization. A total of 85 genes with altered expression were finally identified, with 41 genes from the forward library and 44 from the reverse library. Subsequently, the antagonistic effects of candidate traditional Chinese medicines were evaluated based on the genetic transcription levels of the genes with significant altered expression, including Catnβ, Flt3-L, IL-7r and Rpo2-4. The results indicated that Silybum marianum (L.) Gaert and Ganoderma lucidum had significant down-regulated effects on the transcription level of Catnβ that was up-regulated by α-amanitin, and the two herbs also up-regulated the transcription levels of Flt3-L and Rpo2-4. Silybum marianum (L.) had significant up-regulated effects on the IL-7r that was down-regulated by α-amanitin. These preliminary studies suggested that Silybum marianum (L.) and Ganoderma lucidum were effective antagonists against the toxicity of α-amanitin.
Uniformity in the height of main stem and tillers is a key factor affecting ideal plant type, a key component in super high-yielding rice breeding. An understanding of the genetic basis of the panicle layer uniformity may thus contribute to breeding varieties with good plant type and high yield. In the present study, a doubled haploid (DH) population, derived from a cross between indica rice variety Zhai-Ye-Qing 8 (ZYQ8) and japonica rice variety Jing-Xi 17 (JX17) was used to analyze quantitative trait loci (QTL) for panicle layer uniformity related traits. Six, four and three QTL were detected for the highest panicle height (HPH), lowest panicle height (LPH) and panicle layer dis-uniformity (PLD), respectively. qHPH-1-1 and qPLD-1 were located at the same interval on chromosome 1. The JX17 allele(s) of these QTL increased HPH and PLD by 2.57 and 1.26 cm, respectively. Similarly, qPLD-7 and qHPH-7 were located at the same interval on chromosome 7, where the ZYQ8 allele(s) increased HPH and PLD by 3.74 and 1.96 cm, respectively. These four QTL were unfavourable for panicle layer uniformity improvement because a decrease of the PLD was accompanied by decrease of the plant height. qPLD-6 and qLPH-6-1 were located at the same interval on chromosome 6, however here the JX17 allele(s) increased LPH, but decreased PLD, suggesting that this QTL was favourable for improvement of panicle layer uniformity. The markers identified in this study are potential for marker assisted breeding for the improvement of the panicle layer uniformity and ideal plant type.
Abstract
Myricetin has been reported to have a wide variety of beneficial physiological functions. The present study investigated the antihyperlipidaemic activity of myricetin against hyperlipidaemia of high-fat diet-fed obese rats. The four-week antihyperlipidaemic activity was assayed by giving different doses of myricetin to hyperlipidaemic rats. Results showed that myricetin could reduce the harm caused by oxidative stress, decrease thiobarbituric acid reactive substances value, and decrease total cholesterol and triacylglycerol levels of hyperlipidaemic rats. Quantitative analysis of gene expression showed that myricetin's lipid-lowering activity can be activated by downregulating gene expression of fatty acid synthase (FAS) and peroxisome proliferator-activated receptor-γ (PPARγ) with upregulation of hormone-sensitive lipase (HSL) mRNA level. Thus, myricetin had significant health benefits and could be explored as a potentially promising dietary supplement for treating hyperlipidaemia.
Rht18, derived from Triticum durum (tetraploid) wheat, is classified as a gibberellic acid (GA)-responsive dwarfing gene. Prior to this study, the responses of Rht18 to exogenous GA on agronomic traits in hexaploid wheat were still unknown. The response of Rht18 to exogenous GA3 on coleoptile length, plant height, yield components and other agronomic traits were investigated using F4:5 and F5:6 hexaploid dwarf lines with Rht18 derived from two crosses between the tetraploid donor Icaro and tall Chinese winter wheat cultivars, Xifeng 20 and Jinmai 47. Applications of exogenous GA3 significantly increased coleoptile length in both lines and their tall parents. Plant height was significantly increased by 21.3 and 10.7% in the GA3-treated dwarf lines of Xifeng 20 and Jinmai 47, respectively. Compared to the untreated dwarf lines, the partitioning of dry matter to ears at anthesis was significantly decreased while the partitioning of dry matter to stems was significantly increased in the GA3-treated dwarf lines. There were no obvious changes in plant height and dry matter partitioning in the GA3-treated tall parents. Exogenous GA3 significantly decreased grain number spike–1 while it increased 1000-kernel weight in both the dwarf lines and tall parents. Thus, applications of exogenous GA3 restored plant height and other agronomic traits of Rht18 dwarf lines to the levels of the tall parents. This study indicated that Rht18 dwarf mutants are GA-deficient lines with impaired GA biosynthesis.
Aegilops sharonensis (Sharon goatgrass) is a valuable source of novel high molecular weight glutenin subunits, resistance to wheat rust, powdery mildew, and insect pests. In this study, we successfully hybridized Ae. sharonensis as the pollen parent to common wheat and obtained backcross derivatives. F1 intergeneric hybrids were verified using morphological observation and cytological and molecular analyses. The phenotypes of the hybrid plants were intermediate between Ae. sharonensis and common wheat. Observations of mitosis in root tip cells and meiosis in pollen mother cells revealed that the F1 hybrids possessed 28 chromosomes. Chromosome pairing at metaphase I of the pollen mother cells in the F1 hybrid plants was low, and the meiotic configuration was 25.94 I + 1.03 II (rod). Two pairs of primers were screened out from 150 simple sequence repeat markers, and primer WMC634 was used to identified the presence of the genome of Ae. sharonensis. Sequencing results showed that the F1 hybrids contained the Ssh genome of Ae. sharonensis. The sodium dodecyl sulfate polyacrylamide gel electrophoresis profile showed that the alien high molecular weight glutenin subunits of Ae. sharonensis were transferred into the F1 and backcross derivatives. The new wheat-Ae. sharonensis derivatives that we have produced will be valuable for increasing resistance to various diseases of wheat and for improving the quality of bread wheat.
Abstract
There have been contradicting observations regarding the prebiotic efficacy of feruloylated oligosaccharides (FOs) extracted from different varieties of cereals with varying oligosaccharides and ferulic acid (FA) levels. The present study was performed to determine whether the mass ratio of xylooligosaccharide (XOS) to FA influences their combined effects on faecal FA content, short chain fatty acid (SCFA) output, and gut stress of d-galactose-treated aging rats. The results show that there was no significant difference in the faecal FA levels of rats fed with 5:1 and 10:1 XOS:FA diet, although the FA level in the 5:1-supplemented diet was twice as much as in the 10:1 diet. More utilisation of FA decreased butyric acid and SCFA output in the faeces for diet 5:1 compared with diets 10:1 XOS:FA or XOS alone. Furthermore, compared with 10:1 XOS:FA or XOS alone treatments, the 5:1 XOS:FA diet resulted in increased 1-diphenyl-2-picrylhydrazyl activity and higher ratios of Bifidobacterium or Lactobacillus to Escherichia coli (P < 0.05), while not increasing the number of probiotic Bifidobacterium and Lactobacillus. These findings suggest that under the specific stress level set for this study, the sufficient amount of FA added to XOS (5:1) can stimulate FA utilisation to modify gut redox balance, while reducing faecal SCFA output.
The waxy wheat shows special starch quality due to high amylopectin content. However, little information is available concerning the development and degradation of amyloplast from waxy wheat endosperm. To address this problem, waxy wheat variety, Yangnuo 1, and a non-waxy wheat variety, Yangmai 13, were chosen to investigate the development and degradation of endosperm amyloplast during wheat caryopsis development and germination stage respectively using histochemical staining and light microscopy. Changes of morphology, the soluble sugar and total starch content were indistinguishable in the process of caryopsis development of two wheat varieties. The developing endosperm of non-waxy was stained blue-black by I2-KI while the endosperm of waxy wheat was stained reddish-brown, but the pericarp of waxy and non-waxy wheat was stained blue-black. In contrast to nonwaxy wheat, endosperm amyloplast of waxy wheat had better development status and higher proportion of small amyloplast. During seed germination many small dissolution pores appeared on the surface of endosperm amyloplast and the pores became bigger and deeper until amyloplast disintegrated. The rate of degradation of waxy wheat endosperm amyloplast was faster than non-waxy wheat. Our results may also be helpful to the use of waxy starch in food and nonfood industry.
