Genetic control of juvenile resistance to powdery mildew in spring bread wheat cultivars from the VIR collection

Background. Bread wheat (Triticum aestivum L.) is one of the major food crops of humankind. Powdery mildew, caused by Blumeria graminis f. sp. tritici, is the most destructive foliar disease capable of causing great yield losses in epidemic years. Breeding for resistance to powdery mildew is the most economical and effective way to control this disease. By now, 68 loci were identified to contain more than 90 alleles of resistance to powdery mildew in wheat. However, there is a permanent necessity in finding new sources of resistance.The objective of the present study was to characterize the seedling powdery mildew resistance in some spring bread wheat varieties from the VIR collection and determine the inheritance of powdery mildew resistance in these accessions.Materials and methods. The powdery mildew resistant varieties ‘SW Kungsjet’ (k-66036), ‘SW Kronjet’ (k-66097), ‘Boett’ (k-66353), ‘Batalj’ (k-67116), ‘Stilett’ (k-67119) ‘Pasteur’ (k-66093) were crossed with a resistant line ‘Wembley 14.31’ (k-62557) containing the Pm12 gene, and with ‘SW Milljet’ (k-64434); the variety ‘Sibirka Yartsevskaya’ (k-38587) was used as a susceptible parent and control. The hybrid populations F2 were inoculated with the fungus population from local field and evaluated. The powdery mildew population manifested virulence to Pm1a, Pm2, Pm3a-f, Pm4a-b, Pm5a, Pm6, Pm7, Pm8, Pm9, Pm10, Pm11, Pm16, Pm19, Pm28, and avirulence to Pm12. The degree of resistance was assessed on days 8 and 10 after the inoculation using the Mains and Dietz scale (Mains, Dietz, 1930). The castrated flowers in the spikes were pollinated using the twell-method (Merezhko et al., 1973). Chi-squared for goodness of fit test was used to determine deviation of the observed data from the theoretically expected segregation.Results. According phytopathological and genetic tests, juvenile resistance in the varieties ‘SW Kungsjet’, ‘SW Kronjet’, ‘Boett’, ‘Batalj’, ‘Stilett’ and ‘Pasteur’ is controlled by dominant genes, which differ from Pm1a, Pm2, Pm3a-f, Pm4a-b, Pm5a, Pm6, Pm7, Pm8, Pm9, Pm10, Pm11, Pm12, Pm16, Pm19, and Pm28. The varieties ‘SW Milljet’, ‘SW Kronjet’ and ‘Pasteur’ had identical resistance genes. Genetic control of juvenile resistance to powdery mildew in ‘Batalj’, ‘Boett’, ‘Stilett’, ‘SW Milljet’, ‘SW Kungsjet’, ‘Pasteur’ was governed by different genes.Conclusions. The varieties ‘SW Kungsjet’, ‘SW Kronjet’, ‘Boett’ have been maintaining adult and seedling resistance since 2005, and ‘Batalj’, ‘Stilett’ and ‘Pasteur’ since 2017. Seedling resistance of these varieties to local powdery mildew population is controlled by dominant genes. A high degree of resistance was displayed by ‘SW Kungsjet’ and ‘SW Kronjet’ in the Novosibirsk Province, while ‘SW Kungsjet’ was resistant to mildew populations of Tatarstan. The variety ‘Pasteur’ manifested seedling resistance to leaf rust, and ‘SW Kungsjet’ was resistant to loose smut. By summing all the results, it may be suggested that the varieties ‘SW Kungsjet’, ‘SW Kronjet’, ‘Boett’, ‘Batalj’, ‘Stilett’ and ‘Pasteur can serve as good donors of powdery mildew resistance in wheat breeding.

Novel Fusarium Wilt Resistance Genes Uncovered in the Wild Progenitors and Heirloom Cultivars of Strawberry

Fusarium wilt, a soilborne disease caused by Fusarium oxysporum f. sp. fragariae, poses a significant threat to strawberry (Fragaria × ananassa) production in many parts of the world. This pathogen causes wilting, collapse, and death in susceptible genotypes. We previously identified a dominant gene (FW1) on chromosome 2B that confers resistance to race 1 of the pathogen and hypothesized that gene-for-gene resistance to Fusarium wilt was widespread in strawberry. To explore this, a genetically diverse collection of heirloom and modern cultivars and wild octoploid ecotypes were screened for resistance to Fusarium wilt races 1 and 2. Here we show that resistance to both races is widespread and that resistance to race 1 is mediated by dominant genes (FW1, FW2, FW3, FW4, and FW5) on three non-homoeologous chromosomes (1A, 2B, and 6B). The resistance proteins encoded by these genes are not yet known; however, plausible candidates were identified that encode pattern recognition receptor or other proteins known to mediate gene-for-gene resistance in plants. High-throughput genotyping assays for SNPs in linkage disequilibrium with FW1-FW5 were developed to facilitate marker-assisted selection and accelerate the development of race 1 resistant cultivars. This study laid the foundation for identifying the genes encoded by FW1-FW5, in addition to exploring the genetics of resistance to race 2 and other races of the pathogen, as a precaution to averting a Fusarium wilt pandemic.

Therapeutic Potential of α-Synuclein Evolvability for Autosomal Recessive Parkinson’s Disease

The majority of Parkinson’s disease (PD) is sporadic in elderly and is characterized by α-synuclein (αS) aggregation and other alterations involving mitochondria, ubiquitin-proteasome, and autophagy. The remaining are familial PD associated with gene mutations of either autosomal dominant or recessive inheritances. However, the former ones are similar to sporadic PD, and the latter ones are accompanied by impaired mitophagy during the reproductive stage. Since no radical therapies are available for PD, the objective of this paper is to discuss a mechanistic role for amyloidogenic evolvability, a putative physiological function of αS, among PD subtypes, and the potential relevance to therapy. Presumably, αS evolvability might benefit familial PD due to autosomal dominant genes and also sporadic PD during reproduction, which may manifest as neurodegenerative diseases through antagonistic pleiotropy mechanism in aging. Indeed, there are some reports describing that αS prevents apoptosis and mitochondrial alteration under the oxidative stress conditions, notwithstanding myriads of papers on the neuropathology of αS. Importantly, β-synuclein (βS), the nonamyloidogenic homologue of αS, might buffer against evolvability of αS protofibrils associated with neurotoxicity. Finally, it is intriguing to predict that increased αS evolvability through suppression of βS expression might protect against autosomal recessive PD. Collectively, further studies are warranted to better understand αS evolvability in PD pathogenesis, leading to rational therapy development.

On the issue of winter triticale selection improvement in the Central region non-Black Earth area conditions

In the conditions of the Moscow region, in 1993-2020, more than 1.0 thousand Triticale Wittmack cultivars were studied, including new varieties and lines, by using diallel crossings (DIAC) (5 × 5) and other field and laboratory experiments. Tests of varietal samples in DIAC in 2011-2012 using the method of Hayman (1954) showed that the traits of winter triticale are characterized by an additive-dominant inheritance scheme. The dominant genes made the main contribution to the increase in productivity traits, and the prospects of a particular cross-breeding combination depended on their concentration. In the competitive test (CSI) in 2015-2020, the best productivity was found in the Gera variety - 8.15 t/ha (the standard one is 7.29 t/ha). It is shown that over the past 25 years in the Federal Research Center “Nemchinovka” created more than 25 varieties of winter triticale, 12 varieties submitted to the State Register, 6 varieties are now in production, including variety Nina, released in 2013 for the Central region and combines with Samara Research Institute of Agriculture variety Capella, made to the State Register from 2019.

Study On The Mechanism of Color Formation In The Skin of Ophiopogon Japonicas Fruit Via Integrative Analysis of Metabolome And Transcriptome

In this study, the metabolome and transcriptome profiles of ophiopogon japonicas fruit during five stages were analyzed to understand the mechanisms for the formation of color in the skin. Results showed that twenty eight types of flavonoids existed in the skin of the fruit, of which twenty five were anthocyanins and three were flavonols. Among the twenty five kinds of anthocyanins, Delphinidin 3-O-rutinoside, Delphinidin 3-O-glucoside, Petunidin 3-O-rutinoside, Cyanidin 3-O-galactoside and Delphinidin 3-O-galactoside were the major constitutes of the metabolites. Delphinidin 3-O-rutinoside and Delphinidin 3-O-glucoside were discovered to be responsible for the blue color of fruit due to their high correlation with genes in the connection network, especially for Delphinidin 3-O-rutinoside, which was the highest in the amount and accumulated rapidly to 67.6% in the last three stages. Analyzing the results of co-expression network between genes and anthocyanins by means of weighted gene co-expression network analysis (WGCNA), the biosynthesis genes of anthocyanin formed in the late stage were found to be F3’5’H, ANS and UFGT, and the regulatory gene was MYB, which determined the color change of O. japonicas fruit. The identification of key anthocyanins and dominant genes for blue skin of O. japonicas fruit has laid a theoretical basis for regulating the fruit pigmentation in ground cover plants.

Identification of the Combining Ability of Grain Yield and Its Components in Hybrid Barley (Hordeum Vulgare L.) Populations Based on Top Cross Analysis

The top cross method for assessing combining ability more economical and less laborious compared to diallel analysis, and also allows the breeder to obtain quite valuable information about the inbred material. In this research, the determination of the general (GCA) and specific (SCA) combining ability of barley (Hordeum vulgare L.) hybrids in two regions of Kazakhstan contrasting in soil and climatic conditions, the role of additive and non-additive genes in the determination of the traits under study has been revealed. It is concluded that the predominance of additive gene interactions in the control of the traits understudying the conditions of the Aral Sea region indicates the possibility of effective selection already in the F2 generation, and in the piedmont zone of the Almaty region, due to the high determination of these traits by dominant genes, it is necessary to differentiate the populations of hybrids, starting from the first generation and further selection shall be carried out in several cycles until the achievement of homozygosity of loci carrying dominant genes. Consequently, the genetic contribution of the additive and non-additive effects of genes to the determination and inheritance of the studied traits significantly depends on the conditions of growing the genotypes of spring barley. Of greatest practical interest are the varieties Rihane, WI2291/Roho/WI2269 from the International Center ICARDA and the variety-tester Odessa 100 (Odessa Selection and Genetic Institute, Ukraine) with high GCA and SCA effects, little dependent on growing conditions, which are recommended to be used as reliable donors in breeding programs.

Tissue Specific Heterophile Aggregation of Protogenes Promoted Heterosis

A plethora of studies have described heterosis or hybrid vigor; however, a global understanding of its regulation and the transmission of transcriptional levels between parents and hybrid has yet to be attained. To improve our understanding the molecular mechanisms controlling maize heterosis, we used an incomplete diallel cross design consisting of four elite maize inbred lines and six of their hybrids to measure the degree of variation in gene expression between the parents and their hybrids. We found that differentially expressed genes (DEGs) drove diversity of tissue specific heterosis and that heterophile expression was a generally complementary mechanism of gene expression in hybrids. However, the full expression of heterosis was due to the proportion of super dominant gene expression patterns that aggregate the regulatory network of dominant genes in response to adversity, and thus promotes heterosis in hybrids. Our results provide a new understanding and perspective into the regulatory mechanisms that control heterosis and represent an important step towards a more comprehensive explanation of heterosis in maize.

Identification of the combining abilit o f grain yield and its components in hybrid barley populations based on topcross analysis

The topcross method for assessing combining abilityis more economical and less laborious compared to diallel analysis, and also allows the breeder to obtain quite valuable information about the inbred material. In this research, the determination of the general (GCA) and specific (SCA) combining ability of barley (Hordeum vulgare L.) hybridsin two regions of Kazakhstan contrasting in soil and climatic conditions,the role of additive and non-additive genes in the determination of thetraits understudyhas beenrevealed. It is concluded thatthe predominance of additive gene interactions in the control of the traits understudyin theconditions of the Aral Sea region indicates the possibility of effective selection already in the F 2 generation, and in the piedmontzone of the Almaty region, due to the high determination of these traits by dominant genes, it is necessary to differentiate the populations of hybrids, starting from the first generation and further selection shall be carried out in several cycles until the achievement of homozygosity of loci carrying dominant genes. Consequently, the genetic contribution of the additive and non-additive effects of genes to the determination and inheritance of the studied traits significantly depends on the conditions of growing the genotypes of spring barley. Of greatest practical interest are the varieties Rihane, WI2291/Roho/WI2269 from the International Center ICARDA and the variety-tester Odessa 100 (Odessa Selection and Genetic Institute, Ukraine) with high GCA and SCA effects, little dependent on growing conditions, which are recommended to be used as reliable donors in breeding programs.

Inheritance of photo-sensitivity in pigeonpea

Pigeonpea [Cajanus cajan (L.) Millsp.] is a short-day legume species and the late maturing genotypes are more photosensitive than early types. To generate information about the inheritance of photo-sensitivity, this study was conducted under natural and artificially extended (16 h) photo-periods using F1, F2 and BC1F1 generations. Under natural photo-period, F1 hybrids showed partial dominance of earliness; while in F2 , a normal distribution that was skewed towards earliness was observed. In contrast under extended photo-period, the spread of F2 data was wide with discontinuities recorded at day 70, 82 and 103. Chisquare tests, when applied to F2 and BC1F1 data, suggested that three dominant genes (PS3 , PS2 and PS1 ) controlled the expression of photo-sensitivity. These genes were found operating in a hierarchical order with PS2 and PS1 genes failing to express in the presence of PS3 gene. Similarly in the absence of PS3 gene, PS2 expressed but it masked the expression of PS1 . Further, PS1 gene expressed only when both PS3 and PS2 were in recessive homozygous state. Hence, the proposed genetic model for photosensitivity in pigeonpea is PS3 > PS2 > PS1 and photoinsensitive genotype being a triple recessive (ps3ps3ps2 ps2ps1ps1 ). .

Genetics of Orange, Red and Yellow Root Colours in Tropical Carrots (Dacus Carota L.)

The research was carried out to study the colour inheritance genetics of the root epidermis, core (phloem) and cortex (xylem), from the parental crosses of the varieties Pusa Meghali (Orange), Pusa Rudhira (Red) and Pusa Kulfi (Yellow). Resultant in crosses yielded uniform mixed colours in F1 (first filial generation), thus could enhance the security of human nutrition through the mixture of carotenoids and anthocyanins in the F1. The F1s were advance to produce F2 and backcross (BCP1 and BCP2) generations, and the Chi-square test ratio (χ2) showed that the root colour of the orange epidermis and cortex (xylem) was dominant over the red and yellow colours, and regulated by dominant genes Oe and Ocx from the parent Pusa Meghali. While, the root colour of the orange core (phloem) was found to be recessive to the red (Rc) from Pusa Rudhira and yellow (Yc) colour from Pusa Kulfi, and to be regulated by a single recessive gene (oc) from the parent Pusa Meghali. These finding of genetic inheritance of colours would be useful in the development of bio-fortified F1 hybrids and varieties which are rich in flavonoids.