Allelic Variation at the TaZds-A1 Locus on Wheat Chromosome 2A and Development of a Functional Marker in Common Wheat

ζ （zeta）-carotene desaturase （ZDS） is a key enzyme for carotenoid biosynthesis, demonstrating high association with the yellow pigment （YP） content in wheat grain. Cloning ZDS gene and developing functional markers are important for marker-assisted selection in wheat breeding. In the present study, the full-length DNA sequence of a ZDS gene on wheat chromosome 2A, designated TaZds-A1, was cloned, with 14 exons and 13 introns, and it has an open reading frame （ORF） of 1 707 bp, encoding 568 amino acid residues. A co-dominant functional marker, YP2A-1, was designed based on the polymorphisms of two alleles at the locus, TaZds-Ala and TaZds-Alb, yielding 183- and 179-bp fragments in TaZds-Ala and TaZds-Alb genotypes, respectively. A new QTL for YP content was detected on chromosome 2A, co-segregating with the functional marker YP2A-1 and TaZds-A1; it explained 11.3% of the phenotypic variance for YP content in a doubled haploid （DH） population from Zhongyou 9507/CA9632. Among 217 Chinese wheat cultivars and advanced lines, the average grain YP content of 126 cultivars with TaZds-Alb allele was 7.8% higher than that of 91 cultivars with TaZds- Ala allele.

Application of Functional Markers to Identify Genes for Bacterial Blight Resistance in Oryza rufipogon

Field resistances of nine accessions of common wild rice （Oryza rufipogon Griff.） and one rice variety （IR24） were evaluated by using nine strains of bacterial blight pathogen （Xanthomonas oryzae pv. oryzae） from the Philippines. IR24 was highly susceptible to all the strains, and six common wild rice accessions resisted all the nine strains, with a resistance frequency of 67%. The accessions Yulin and Wanning were only susceptible to PXO280 and PXO71, respectively. The accession Gaozhou was susceptible to the three strains PXO79, PXO99 and PXO339, whereas resistant to the other six strains. It could be concluded that there is at least one resistance gene in each common wild rice accession. The functional markers of the genes xa5, xa13, Xa21 and Xa27 were used to detect the presence of these resistance genes in the nine tested wild rice accessions, and it was found that four wild rice accessions contained heterozygous xa13. Among the nine common wild rice accessions, five were homozygous for Xa27 and three homozygous for xa27, and the accession Laibin contained neither xa27 nor Xa27. In addition, there were no xa5 and Xa21 in all of these accessions.

Analysis of the Relationship between Blast Resistance Genes and Disease Resistance of Rice Germplasm via Functional Molecular Markers

Rice blast disease is one of the most devastating diseases of rice(Oryza sativa L.)caused by the fungus Magnaporthe oryzae(M.oryzae),and neck blast is the most destructive phase of this illness.The underlying molecular mechanisms of rice blast resistance are not well known.Thus,we collected 150 rice varieties from different ecotypes in China and assessed the rice blast resistances under the natural conditions that favoured disease development in Jining,Shandong Province,China in 2017.Results showed that 92(61.3%)and 58(38.7%)rice varieties were resistant and susceptible to M.oryzae,respectively.Among the 150 rice varieties screened for the presence of 13 major blast resistance(R)genes against M.oryzae by using functional markers,147 contained one to eight R genes.The relationship between R genes and disease response was discussed by analysing the phenotype and genotype of functional markers.The results showed that the rice blast resistance gene Pita was significantly correlated with rice blast resistance.Our results provided a basis for the further understanding of the distribution of 13 major R genes of rice blast in the germplasm resources of the tested rice varieties,and were meaningful for rice disease resistance breeding.

Characterization of Myanmar Paw San Hmwe Accessions Using Functional Genetic Markers

Paw San Hmwe （PSM） rice has been cultivated in many areas of Myanmar for a long time. Strong aroma, good taste and its elongation during cooking are the key characteristics of PSM rice. Thirty-one PSM accessions were genotypically characterized, and their physical grain and cooking quality traits were studied. We used specific gene markers associated with aroma, apparent amylose content （AAC） and alkali spreading value to determine the alleles carried by different PSM accessions. The results revealed that six PSM accessions （PSM10, PSM12, PSM13, PSM21, PSM22 and PSM30） had a 3-bp insertion in Os2AP gene. Gel consistency （GC） allele was predominant among the PSM accessions for gelatinization temperature （GT）, however, the phenotype observed was between low and intermediate GT because of the combination of the GC allele with the presence of low GT allele at heterozygous state from the other loci of the SSIla gene. Intermediate to high AAC was observed among the PSM accessions corresponding to the haplotype identified for the single nucleotide polymorphism G/T and the （Cm）n repeat in the Wx gene. The characterization and grouping data of PSM accessions posted benefits to Myanmar seed banks, and our results will help in maintaining the integrity of PSM rice variety.

Release of Cardiac Biomarkers during a Cycling Race

Objectives: Over the past two decades, a large interest in cardiac marker elevations has developed in endurance sports events. The intense effort is not without risk. We aimed to see if the relatively cardiospecific biomarkers could show the damage on cardiac muscle cells. Methods: Fourteen cyclists were recruited for an international race (177 km). We studied different cardiac biomarkers, renal function markers and blood cytology. The subjects were submitted to three blood test: one before (T0), one just after (T1) and the last one 3 hours after the race (T3). Results: Blood cytology markers, namely erythrocytes, hemoglobin, hematocrit, and average hemoglobin concentration, were found to evolve in a similar way. Renal function markers, such as creatinin, cystatin C and uric acid, showed a post effort increase that might be related to renal blood flow depletion during exercise. Cardiac and muscular markers were all increased at T1. Conclusions: Physiological stress induced by an international cycling race certainly has consequences on cardiac muscle cells. Fortunately, those blood concentration variations are more representative of a transitional state, due to an imbalance created by an intense aerobic effort maintained during several hours, rather than an irreversible injury.

Development of new aromatic rice lines with high eating and cooking qualities

Rice is the staple food for about half of the world’s population.Preferred by consumers,aromatic rice is a special type of rice with great commercial value.Cooking and eating qualities and aroma are the major grain qualities favored by most consumers.Currently,most of the available aromatic varieties have low yields and some undesirable agronomic traits.Thus,there is an urgent need to develop better aromatic rice varieties.This work aims to identify rice germplasm lines that have good grain quality and to develop new varieties with desirable traits.Thirty-six out of 188 germplasm lines were found to have betaine aldehyde dehydrogenase 2 (badh2) controlling the aroma and were analyzed for their 2-acetyl-1-pyrroline (2AP) contents.Then,17 of those lines were found to have alleles for low amylose content and low gelatinization temperature,controlled by waxy and starch synthase Ⅱa (SSⅡa),respectively,suggesting that they are aromatic rice lines with high cooking and eating qualities.A total of 158 F_(7)recombinant inbred lines (RILs) generated from five crosses of the selected germplasm lines were planted for phenotypic and yield observations,resulting in 27 F_(8)RILs selected for yield evaluation and genotyping.Finally,four out of the seven F_(9)aromatic RILs showed high yield,high 2AP production,and low amylose content,in agreement with their genotypes.The other three F9RILs were aromatic rice lines with high amylose content and high yield.Because consumer preferences for grain quality vary depending on regions and ethnic groups,the high-yielding aromatic RILs generated from this study can be used to increase the yield of Thai rice and to raise market value and farm profits.

Integrated genomic and transcriptomic analysis reveals genes associated with plant height of foxtail millet

Foxtail millet(Setaria italica)is an important C4 model crop;however,due to its high-density planting and high stature,lodging at the filling stage resulted in a serious reduction in yield and quality.Therefore,it is imperative to identify and deploy the genes controlling foxtail millet plant height.In this study,we used a semi-dwarf line 263A and an elite high-stalk breeding variety,Chuang 29 to construct an F2 population to identify dwarf genes.We performed transcriptome analysis(RNA-seq)using internode tissues sampled at three jointing stages of 263A and Chuang 29,as well as bulk segregant analysis(BSA)on their F2 population.A total of 8918 differentially expressed genes(DEGs)were obtained from RNA-seq analysis,and GO analysis showed that DEGs were enriched in functions such as‘‘gibberellin metabolic process”and‘‘oxidoreductase activity”,which have previously been shown to be associated with plant height.A total 593 mutated genes were screened by BSA-seq method.One hundred and seventy-six out of the 593 mutated genes showed differential expression levels between the two parental lines,and seven genes not only showed differential expression in two or three internode tissues but also showed high genomic variation in coding regions,which indicated they play a crucial role in plant height determination.Among them,we found a gibberellin biosynthesis related GA20 oxidase gene(Seita.5G404900),which had a single-base at the third exon,leading to the frameshift mutation at 263A.Cleaved amplified polymorphic sequence assay and association analysis proved the single-base in Seita.5G404900 co-segregated with dwarf phenotype in two independent F2 populations planted in entirely different environments.Taken together,the candidate genes identified in this study will help to elucidate the genetic basis of foxtail millet plant height,and the molecular marker will be useful for marker-assisted dwarf breeding.

Novel Deletion in Exon 7 of Betaine Aldehyde Dehydrogenase 2(BADH2)

The fragrance of rice is one of the premium characteristics that breeders want to include in rice varieties due to the higher market value. Nucleotide deletions in exons 2(7 bp) and 7(8 bp) of Betaine Aldehyde Dehydrogenase 2(BADH2) are associated with fragrance in rice. In this study, a new 13 bp deletion in exon 7 of the BADH2 gene was discovered in the Nang Thom Cho Dao(NTCD) variety, and the mutation has been closely related to the genetic background of indica subspecies through the Bayesian phylogenetic approach and haplotype network analysis of the 3 000 Rice Genomes Project. In addition, a set of functional markers(EX07-13F, EX07-13RN, and EX07-13RM) identified the 13 bp deletion only within NTCD(no amplified band) compared with both non-aromatic and other aromatic rice varieties(110 bp band). The deletion of 13 bases instead of 8 bases in exon 7 of BADH2 caused a premature stop codon, which down-regulated the expression of the BADH2 transcript while associated with up-regulation of OsP5CS and the high amount of 2-acetyl-1-pyrroline. It is potential to use the deletion in exon 7 of the BADH2 gene as a novel marker for adulteration and breeding of fragrant rice varieties, particularly for NTCD.

Biological in Vitro and in Vivo Studies of the Milk Thistle Seed Oil

The milk thistle plant is one of the famous plants that have been gaining popularity for its therapeutic potential for centuries. Milk thistle seed oil (MTSO) has been subjected to extensive research. The fixed oil was extracted from the seeds of Silybum marianum (L.) using petroleum ether as a solvent by a soxhlet device. GC-MS was used to identify the chemical composition of the oil. The antioxidant activity of MTSO was tested by the ABTS method, which showed the ability to inhibit lipid peroxidation. In addition, antimicrobial and antifungal investigations were examined. It proved that MTSO has an inhibitory effect against Gram-positive bacteria (Staphylococcus aureus), Gram-negative bacteria (Escherichia coli), and antifungal effects (Candida albicans). MTSO has a slightly higher effectiveness against fungi than bacteria. Moreover, the cytotoxic activities of the oil on hepatocellular and colorectal carcinoma were examined. MTSO has shown a moderate cytotoxic effect on the HCT-116 cell line and a weak effect on HePG-2. Whereas;in vivo study has been done on five diagnosed patients who have impaired liver function, and were recruited for the study. Their weight ranged from 100 ± 30 kg, their age range was between 39 - 50 years. Each patient was given ten drops of MTSO daily and added to a little water for a four-week study period. MTSO has effects to improve the function of the injured liver. The present work aims to study Milk thistle seed oil, for estimating its pharmacological properties for the liver. This study focused on showing the importance of milk thistle seed oil in our lives as a source of antioxidants, anti-bacterial and anti-fungal, and as an anti-cancer of the liver and colon. It also sheds light on its importance as a treatment for impaired liver, function and fatty liver, due to its improvement in all liver function markers, so it can be hired as an effective human therapy.

Yield-related QTLs and Their Applications in Rice Genetic Improvement

Grain yield is one of the most important indexes in rice breeding, which is governed by quantitative trait loci （QTLs）. Different map- ping populations have been used to explore the QTLs controlling yield related traits. Primary populations such as F2 and recombi- nant inbred line populations have been widely used to discover QTLs in rice genome-wide, with hundreds of yield-related QTLs detected. Advanced populations such as near isogenic lines （NILs） are efficient to further fine-map and clone target QTLs. NILs for primarily identified QTLs have been proposed and confirmed to be the ideal population for map-based cloning. To date, 20 QTLs directly affecting rice grain yield and its components have been cloned with NIL-F2 populations, and 14 new grain yield QTLs havebeen validated in the NILs. The molecular mechanisms＇of＇a continuous/y increasing number of genes are being unveiled, which aids in the understanding of the formation of grain yield. Favorable alleles for rice breeding have been ＇mined＇ from natural cultivars and wild rice by association analysis of known functional genes with target trait performance. Reasonable combination of favorable alleles has the potential to increase grain yield via use of functional marker assisted selection.