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Copyright of Journal of Agriculture & Nature / Kahramanmaraş Sütçü İmam Üniversitesi Tarım & Doğa Dergisi is the property of Kahramanmaras Sutcu Imam Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Four molecular marker systems--RAPD (random amplified polymorphic DNA), ISSR (intersimple sequence repeat), SRAP (sequence-related amplified polymorphism), and SSR (simple sequence repeat)--were used to evaluate seed genetic purity of a hybrid cabbage cultivar 'Zaoxia 16'. Genetic relationships of the F1 hybrids and their parents were analyzed with 157 RAPD primers, 54 ISSR primers, 84 SRAP primer combinations, and 44 SSR primers. Three RAPD primers (NAURP2006, NAURP2020, and NAURP2031), two ISSR primers (NAUISR1058 and NAUISR1062), one SRAP primer combination (NAUSR04/NAURS05), and two SSR primers (NAUSSR1011 and NAUSSR1031), which produced male and female parent-specific markers simultaneously, were selected for testing the genetic purity of the F1 seeds. A total of 210 'Zaoxia 16' hybrid individuals were investigated with these eight selected primers. Of these, 12 appeared to be false hybrids. Nine of the 12 putative false hybrids, confirmed with all eight primers, exhibited similar banding patterns to the female parent, suggesting that they could be derived from selfing of the female parent. The results were in accordance with those from field evaluations. This study showed that RAPD, ISSR, SRAP, and SSR markers are highly efficient and reproducible for genetic purity testing of cabbage commercial hybrid seeds. [ABSTRACT FROM AUTHOR]

Relevance. Biologically active compounds are widely used at the modern vegetable production, and especially at the seed production. Influence of Micephyt preparation in the mixed with Etrel is evaluated at the first time. The goal of the study is evaluation the effect of Micephyt in the mixed of Etrel on the obtaining of hybrid seeds of the squash (Cucurbita pepo var. giramontia Duch.).Materials and methods. Studies were carried out at the experimental plot Transnistrian State University named T.G. Shevchenko (Tiraspol) during 2010-2012. The object of studies was maternal line F1 (166/5x98/5) of squash (analog of commercial hybrid F1 Lenutsa). Materials of study were preparations: Etrel (c= 0 and 300 ppm) and Micephyt in the mixed with Etrel (c= 10 and 100 ppm). There were 2 treatments of squash plants with these preparations: at the stage 2-3 leaves, and at the stage of 6-7 leaves.Results. Treatments maternal line of squash F1 with mixed preparation “Etrel-300 ppm + Micephyt-10 ppm” show the positive effect on the seed productivity of plants. We observed the significant increasing main components of seed productivity during three years of study. The mass of 1000 seed was increased on 10.1%; the quantity of seed fruits was increased on 9.0%; the quantity of fruits on the plant was increased on 11.8% and the seed productivity was increased on 33.0%. Seed yields of F1 squash were increased in 1.37 times on the standard (“Etrel-300 ppm”) after plant treatment with mixed preparation “Etrel-300 ppm + Micephyt-10 ppm”. High quality of seeds was maintained. The profitability of additional costs associated with the use of the preparation Micephit for the treatment of the maternal line 166/5 squash was 343%. So, the treatment of squash plants with mixed preparation “Etrel-300 ppm + Micephyt-10 ppm” is economic effective element the technology of F1 squash hybrid seed production.

The marker-assisted backcrossing (MAB) can help to transfer an interested allele at a target locus from a donor to a recipient line. Gynoecious is a pivotal trait of cucumber since commercial F1 hybrid seeds produced with gynoecious line as one of the parents are high-yield and affordable. This study aims to transfer the F locus encoded for gynoecious trait to Vietnamese domesticated cucumbers by marker-assisted backcrossing. Two monoecious cucumber lines, A1 (Ha Giang, Vietnam) A2 (Yen Bai, Vietnam), and two gynoecious cucumber lines, B1 (Plantgene, India) and B2 (Hue, Vietnam) were utilized as the starting materials. BCAT marker (located on the F locus) and 52 SSRs (spread across seven chromosomes and tightly linked with some crucial horticultural traits) were used as the foreground and background markers, respectively. With this, phenotype selection for fruit and leaf sizes was also applied. First, using phenotypic screening and foreground marker, A1 (Ha Giang, Vietnam) and B1 (Plantgene, India) were selected as donor and recurrent parents for backcrossing. Then, after two backcrosses followed by two self-pollinations, four gynoecious C cucumber lines were created. These C lines have leaf sizes slightly bigger than the recurrent parent. Importantly, their fruit length is the same or longer than A1 (Ha Giang, Vietnam). These new gynoecious lines could be used as material lines for producing commercial F1 hybrid seeds. [ABSTRACT FROM AUTHOR]

Male sterility is a unique application in the production of F1 hybrid seeds of some important species. Today, while F1 hybrid lettuce varieties of abroad origin take their place in the Türkiye seed market, unfortunately, we do not have a native F1 hybrid variety. Besides, F1 hybrid seed production has become a prestige for multinational companies regardless of the type of vegetable. Within this perspective, the effects of some chemical hybridizing agents (CHAs) such as Ethyl 2-(4-fluoroanilino)-2-oxoacetate E4FO, 2-chloroethyl phosphonic acid (Ethrel) and GA3 on male sterilizing activity in lettuce cultivars (Maylight352 F1, Presidential and Yedikule) were evaluated. Therefore, pollen presence in the early bud stage, seed formation and seed viability (germination) were examined. The applications had different effects on pollen presence, seed formation and seed germination, and thus male sterility. Ethrel was not effective at low doses, but at high doses, it caused flower bud deformation and growth retardation. E4FO is partially effective, but the application doses are low. Therefore, E4FO should be used at higher than 1500 ppm and 2000 ppm. GA3 applications produced the best results in stimulating male sterility, and full sterility (% 100) was achieved from 200, 250 and 300 ppm in all cultivars. As a result, 200 ppm GA3 was determined as the recommendable dose in the production of F1 hybrid lettuce. [ABSTRACT FROM AUTHOR]

Copyright of Manas Journal of Agriculture Veterinary & Life Sciences is the property of Kyrgyz-Turkish Manas University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Avena longiglumis Durieu (2n = 2x = 14) is a wild relative of cultivated oat (Avena sativa, 2n = 6x = 42) with good agronomic and nutritional traits. The plant mitochondrial genome has a complex organization and carries genetic traits of value in exploiting genetic resources, not least male sterility alleles used to generate F1 hybrid seeds. Therefore, we aim to complement the chromosomal-level nuclear and chloroplast genome assemblies of A. longiglumis with the complete assembly of the mitochondrial genome (mitogenome) based on Illumina and ONT long reads, comparing its structure with Poaceae species. Results: The complete mitochondrial genome of A. longiglumis can be represented by one master circular genome being 548,445 bp long with a GC content of 44.05%. It can be represented by linear or circular DNA molecules (isoforms or contigs), with multiple alternative configurations mediated by long (4,100–31,235 bp) and medium (144–792 bp) size repeats. Thirty-five unique protein-coding genes, three unique rRNA genes, and 11 unique tRNA genes are identified. The mitogenome is rich in duplications (up to 233 kb long) and multiple tandem or simple sequence repeats, together accounting for more than 42.5% of the total length. We identify homologous sequences between the mitochondrial, plastid and nuclear genomes, including the exchange of eight plastid-derived tRNA genes, and nuclear-derived retroelement fragments. At least 85% of the mitogenome is duplicated in the A. longiglumis nuclear genome. We identify 269 RNA editing sites in mitochondrial protein-coding genes including stop codons truncating ccmFC transcripts. Conclusions: Comparative analysis with Poaceae species reveals the dynamic and ongoing evolutionary changes in mitochondrial genome structure and gene content. The complete mitochondrial genome of A. longiglumis completes the last link of the oat reference genome and lays the foundation for oat breeding and exploiting the biodiversity in the genus. [ABSTRACT FROM AUTHOR]

Copyright of Guangdong Agricultural Sciences is the property of South China Agricultural University, Guangdong Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sunflower cultivation is particularly important for vegetable oil production worldwide. Therefore, breeding programs have intensified research and development to increase yields by producing F1 hybrid seeds from crosses of inbred lines through the introduction of cytoplasmic androsterility. For the experiment, we used sterile sunflower inbred lines and restorer inbred lines to isolate the restorer gene in a segregation ratio of 1:2:1 in self-fertilization and 1:1 in backcrossing with PET1-type cytoplasm. The results of our research offer breeders the possibility of achieving greater dynamics in the development of inbred lines, the introgression of genetic resistances to sunflower diseases and the stimulation of a greater number of genotypes to increase the combined capacity of sunflower inbred lines. This was achieved by reducing the breeding program from three inbred lines to two inbred lines using sterility genes and heterozygous fertility genes. The use of segregating restoration genes on sterile cytoplasm enables the breeder to form valuable genotypes, adapt quickly to new herbicide technologies and efficiently introduce resistance genes to new disease nomenclatures. [ABSTRACT FROM AUTHOR]

Drought stress is a serious abiotic factor limiting the quality and yield of maize (Zea mays). To produce maize plants with enhanced drought tolerance, we generated transgenic maize plants overexpressing OsPYL/RCAR7, encoding an abscisic acid receptor. We crossed the selected lines with maize variety B73 and obtained F1 hybrid seeds. Initial screening suggested that the transgenic lines were more drought tolerant than wild-type plants. Analysis using the DroughtSpotter platform indicated that expressing OsPYL/RCAR7 enhanced drought resistance in transgenic maize seedlings by reducing water loss. In addition, the stomatal conductance of the leaf surface was 30% lower in OsPYL/RCAR7-overexpressing plants than in wild-type ones. After drought treatment, OsPYL/RCAR7-overexpressing maize showed a much higher survival rate than the wild type, suggesting that expressing OsPYL/RCAR7 reduced the negative effects of drought exposure on stomatal conductance and enhanced water use efficiency. Furthermore, the expression levels of drought-tolerance–related abscisic acid–signaling genes ABP2 and RAB16A were higher in the transgenic plants than in the wild type. Taken together, our data indicate that the seedlings of transgenic maize expressing the gene OsPYL/RCAR7 showed increased tolerance to drought stress, raising the possibility that stress-related genes from monocotyledonous crops could be used as genetic resources to improve the agricultural traits of maize. [ABSTRACT FROM AUTHOR]

SUMMARY: Stigma characteristics are important factors affecting the seed yield of hybrid rice per unit area. Natural variation of stigma characteristics has been reported in rice, but the genetic basis for this variation is largely unknown. We performed a genome‐wide association study on three stigma characteristics in six environments using 1.3 million single‐nucleotide polymorphism (SNPs) characterized in 353 diverse accessions of Oryza sativa. An abundance of phenotypic variation was present in the three stigma characteristics of these collections. We identified four significant SNPs associated with stigma length, 20 SNPs with style length (SYL), and 17 SNPs with the sum of stigma and style length, which were detected repeatedly in more than four environments. Of these SNPs, 28 were novel. We identified two causal gene loci for SYL, OsSYL3 and OsSYL2; OsSYL3 was co‐localized with the grain size gene GS3. The SYL of accessions carrying allele OsSYL3AA was significantly longer than that of those carrying allele OsSYL3CC. We also demonstrated that the outcrossing rate of female parents carrying allele OsSYL2AA increased by 5.71% compared with that of the isogenic line carrying allele OsSYL2CC in an F1 hybrid seed production field. The allele frequencies of OsSYL3AA and OsSYL2AA decreased gradually with an increase in latitude in the Northern Hemisphere. Our results should facilitate the improvement in stigma characteristics of parents of hybrid rice. Significance Statement: The utilization of heterosis in rice is an effective strategy to enhance the grain yield. However, this entails the production of F1 hybrid seeds every year. The yield of F1 hybrid seeds is affected by stigma characteristics. The cloning of OsSYL2AA filled a gap in the genetic study of style length and could be used for improving stigma characteristics to increase the yield of F1 seeds. [ABSTRACT FROM AUTHOR]

Key message: The causal gene, CaHY5 of a chemical induced green-hypocotyl mutant was identified by molecular mapping. CaHY5 regulates anthocyanin accumulation by directly binding to the promoter of genes in anthocyanin pathway. Morphological markers at seedling stage are useful indicators for F1 hybrid seeds screening. Pepper is a worldwide vegetable with diverse uses, and F1 hybrids are popular in the pepper industry. Hypocotyl color is a useful marker to identify F1 hybrid seeds. However, most pepper accessions have purple hypocotyl caused by anthocyanin accumulation, while green hypocotyl pepper accessions are rare. In this study, we identified a green hypocotyl mutant (e1898) from a pepper ethylmethanesulfonate (EMS) mutant library. By combining bulked segregant RNA-seq (BSR), genome resequencing and recombinant analysis, it was found that CaHY5 is the causal gene of this mutant. Virus-induced gene silencing (VIGS) of CaHY5 resulted in the decrease of anthocyanin accumulation in pepper hypocotyls. RNA-seq data showed that many genes related to anthocyanin biosynthesis and transport decreased significantly in the mutant. Yeast one-hybrid (Y1H) assays showed that CaHY5 can bind to the promoter of CaF3H, CaF3′5'H, CaDFR, CaANS and CaGST, which are important genes in anthocyanin biosynthesis or transport. Our results indicate that CaHY5 directly regulates anthocyanin biosynthesis and transport, thus governing anthocyanin accumulation in pepper hypocotyl. The mutant and gene identified in this work shall be valuable in the purity control of hybrid pepper seeds. [ABSTRACT FROM AUTHOR]

Accounts of twentieth-century agricultural industrialization in the United States and beyond often center the production and distribution of commercial F1 hybrid seeds as a pivotal development. The commercialization of hybrid corn seeds in the 1930s was initially heralded as a science-driven advance in agricultural productivity. However, since the 1970s "hybrid seeds" have been linked to many perceived perils attendant on industrialized agriculture, from the undermining of farmers' independence to the diminishment of crop genetic diversity to the consolidation of corporate control over the global food system. First grouped with the semidwarf varieties of the Green Revolution to emblematize capital- and chemical-intensive agriculture, hybrids are today often lumped together with genetically modified varieties for much the same reason. This essay revisits the scholarship that helped produce this understanding of hybrid seeds. It explores how and why the singular history of hybrid corn inflected understandings of crop breeding and seed production in general, contributing to lasting confusion about the promises and pitfalls of distinct approaches to crop development and the nature of hybrid seeds. [ABSTRACT FROM AUTHOR]

Cytoplasmic male-sterility (CMS) has been exclusively used to produce F1 hybrid seeds of onion (Allium cepa L.). A single nuclear locus, Ms, is known to restore male-fertility of CMS in onions. Unstable male-sterile onions producing a small amount of pollen grains have been identified in a previous study. When such unstable male-sterile onions were crossed with stable male-sterile onions containing CMS-R cytoplasm, male-fertility was completely restored, although genotypes of the Ms locus were homozygous recessive. Inheritance patterns indicated that male-fertility restoration was controlled by a single locus designated as Ms2. A combined approach of bulked segregant analysis and RNA-seq was used to identify candidate genes for the Ms2 locus. High resolution melting markers were developed based on single nucleotide polymorphisms (SNPs) detected by RNA-Seq. Comparative mapping of the Ms2 locus showed that Ms2 was positioned at the end of chromosome 2 with a distance of approximately 70 cM away from the Ms locus. Although 38 contigs containing reliable SNPs were analyzed using recombinants selected from 1344 individuals, no contig showed perfect linkage to Ms2. Interestingly, transcription levels of orf725, a CMS-associated gene in onions, were significantly reduced in male-fertile individuals of segregating populations. However, no significant change in its transcription level was observed in individuals of a segregating population with male-fertility genotypes determined by the Ms locus, suggesting that male-fertility restoration mechanism of Ms2 might be different from that of the Ms locus. [ABSTRACT FROM AUTHOR]

Background: Cytoplasmic male sterility (CMS) has been widely used for commercial F1 hybrid seeds production. CMS is primarily caused by chimeric genes in mitochondrial genomes. However, which specific stages of anther development in cabbage are affected by the chimeric genes remain unclear. Results: In the present study, the complete mitochondrial genomes were sequenced and assembled for the maintainer and Ogura CMS cabbage lines. The genome size of the maintainer and Ogura CMS cabbage are 219,962 bp and 236,648 bp, respectively. There are 67 and 69 unknown function ORFs identified in the maintainer and Ogura CMS cabbage mitochondrial genomes, respectively. Four orfs, orf102a, orf122b, orf138a and orf154a were specifically identified in the Ogura CMS mitochondrial genome, which were likely generated by recombination with Ogura type radish during breeding process. Among them, ORF138a and ORF154a possessed a transmembrane structure, and orf138a was co-transcribed with the atp8 and trnfM genes. orf154a is partially homologous to the ATP synthase subunit 1 (atpA) gene. Both these genes were likely responsible for the CMS phenotype. In addition, cytological sections showed that the abnormal proliferation of tapetal cells might be the immediate cause of cytoplasmic male-sterility in Ogura CMS cabbage lines. RNA-seq results showed that orf138a and orf154a in Ogura CMS might influence transcript levels of genes in energy metabolic pathways. Conclusions: The presence of orf138a and orf154a lead to increased of ATPase activity and ATP content by affecting the transcript levels of genes in energy metabolic pathways, which could provide more energy for the abnormal proliferation of tapetal cells. Our data provides new insights into cytoplasmic male-sterility from whole mitochondrial genomes, cytology of anther development and transcriptome data. [ABSTRACT FROM AUTHOR]

Cultivated strawberry is the most widely consumed fruit crop in the world, and therefore, many breeding programs are underway to improve its agronomic traits such as fruit quality. Strawberry cultivars were vegetatively propagated through runners and carried a high risk of infection with viruses and insects. To solve this problem, the development of F1 hybrid seeds has been proposed as an alternative breeding strategy in strawberry. In this study, we conducted a potential assessment of genomic selection (GS) in strawberry F1 hybrid breeding. A total of 105 inbred lines were developed as candidate parents of strawberry F1 hybrids. In addition, 275 parental combinations were randomly selected from the 105 inbred lines and crossed to develop test F1 hybrids for GS model training. These populations were phenotyped for petiole length, leaf area, Brix, fruit hardness, and pericarp color. Whole-genome shotgun sequencing of the 105 inbred lines detected 20,811 single nucleotide polymorphism sites that were provided for subsequent GS analyses. In a GS model construction, inclusion of dominant effects showed a slight advantage in GS accuracy. In the across population prediction analysis, GS models using the inbred lines showed predictability for the test F1 hybrids and vice versa, except for Brix. Finally, the GS models were used for phenotype prediction of 5,460 possible F1 hybrids from 105 inbred lines to select F1 hybrids with high fruit hardness or high pericarp color. These F1 hybrids were developed and phenotyped to evaluate the efficacy of the GS. As expected, F1 hybrids that were predicted to have high fruit hardness or high pericarp color expressed higher observed phenotypic values than the F1 hybrids that were selected for other objectives. Through the analyses in this study, we demonstrated that GS can be applied for strawberry F1 hybrid breeding. [ABSTRACT FROM AUTHOR]

High oil content is one of the most important characteristics of rapeseed ( Brassica napus L.) breeding. In order to understand the genetic basis of seed oil content, a series of reciprocal crosses between rapeseed parents with high oil content (53110, 61616 and 6F313), medium-oil content (Zhongshuang 9) and low oil content (51070 and 93275) were conducted. It was found that the oil content of F1 hybrid seeds in rapeseed was mainly controlled by the maternal genotype. The maternal effect value of oil content was estimated to be 0.86. The pollen parent had a xenia effect on oil content, estimated to be 0.14 which changed the mean value by 1.86 percent. The inheritance of oil content was studied in a set of 8 × 8 diallel crosses of different varieties. The results indicated that the inheritance of oil content could be explained by an additive-dominant-epistasis model. Although the dominant and additive effects played major roles and accounted for more than 70% of the total variance, there was also a small epistatic effect. The broad and narrow sense heritability of oil content was 83.88 and 36.94%, respectively. Based on the oil content differences between the reciprocal crosses in the same offspring generation (F1 and F2) in rapeseed, it could be concluded that there were significant cytoplasmic effects on oil content. In this study, two lines with significantly cytoplasmic effects, either positive or negative, were selected. [ABSTRACT FROM AUTHOR]

A number of studies have been conducted on hybridization between transgenic Brassica napus and B. rapa or backcross of F1 hybrid to their parents. However, trait changes must be analyzed to evaluate hybrid sustainability in nature. In the present study, B. rapa and transgenic (BrAGL20) B. napus were hybridized to verify the early flowering phenomenon of F1 hybrids, and F1 hybrid traits were analyzed to predict their impact on sustainability. Flowering of F1 hybrid has been induced slightly later than that of the transgenic B. napus, but flowering was available in the greenhouse without low temperature treatment to young plant, similar to the transgenic B. napus. It is because the BrAGL20 gene has been transferred from transgenic B. napus to F1 hybrid. The size of F1 hybrid seeds was intermediate between those of B. rapa and transgenic B. napus, and ~40% of F1 pollen exhibited abnormal size and morphology. The form of the F1 stomata was also intermediate between that of B. rapa and transgenic B. napus, and the number of stomata was close to the parental mean. Among various fatty acids, the content of erucic acid exhibited the greatest change, owing to the polymorphism of parental FATTY ACID ELONGASE 1 alleles. Furthermore, F2 hybrids could not be obtained. However, BC1 progeny were obtained by hand pollination of B. rapa with F1 hybrid pollen, with an outcrossing rate of 50%. [ABSTRACT FROM AUTHOR]

Using male sterile (MS) lines instead of normal inbred maternal lines in hybrid seed production can increase the yield and quality with lower production costs. Therefore, developing a new MS germplasm is essential for maize hybrid seed production in the future. Here, we reported a male sterility gene ms*-N125, cloned from a newly found MS mutant ms*-N125. This mutant has an underdeveloped tassel that showed impaired glumes and shriveled anthers without pollen grains. The MS locus of ms*-N125 was mapped precisely to a 112-kb-interval on the chromosome 5. This interval contains only three candidate genes, Zm958, Zm959, and Zm960. Sequencing results showed that only candidate Zm960 harbored a 548-bp transposable element (TE) in its 9th exon, and the two other candidate genes were found to have no genetic variations between the mutant and wild type (WT). Thus, Zm960 is the only candidate gene for male sterility of the mutant ms*-N125. In addition, we screened another recessive MS mutant, ms*-P884, which exhibited similar male sterility phenotypes to ms*-N125. Sequencing Zm960 in ms*-P884 showed a 600-bp TE located in its 2nd exon. Zm960 encodes an ATP-binding cassette in the G subfamily of ABC (ABCG) transporters, ZmABCG2a, with both mutants which harbored an Ac/Ds-like transposon in each. To verify the function of ZmABCG2a for male sterility further, we found an ethyl methanesulfonate (EMS) mutant, zmabcg2a*, which displayed male sterility and tassel phenotypes highly similar to ms*-N125 and ms*-P884, confirming that ZmABCG2a must be the gene for male sterility in maize. In addition, the results of lipid metabolome analysis of ms*-N125 young tassels showed that the total lipid content of the mutant was significantly lower than that of the WT, with 15 subclasses of lipids, including PE (phosphatidylethanolamine), PC (phosphatidylcholine), DG (digalactosyldiacylglycerols), and MGDG (monogalactosyldiacylglycerol) which were significantly down-regulated in the ms*-N125 mutant versus its wild type. In summary, we identified alternate mutations of the ZmABCG2a gene, which may be a potential germplasm for hybrid seed production in maize. [ABSTRACT FROM AUTHOR]

Maize is the second most important staple food crop in the world after wheat. For maize hybrid seed production, a prominent step is detasseling in the female parent, which is laborious, time consuming, and increases the hybrid seed cost by 15 to 20 percent. Hence, to overcome this problem, exploitation of male sterility in maize crops gains special significance. In this direction, the research was conducted to transfer cytoplasmic male sterility (CMS-C) from a CMS donor (VL192114) into the female parents (CAL1514 and ZL153493) of heat- and drought-resilient maize hybrids (RCRMH-2 and RCRMH-3) by a marker-assisted backcross scheme. The present research used Diversity Array Technology (DArTag) and Kompetitive Allele Specific PCR (KASP)-based single-nucleotide polymorphic markers for background selection in backcross populations. Genome recovery percentage ranged from 64.25 to 72.70, 78.94 to 87.69 and 82.28 to 90.77 percent in the BC1F1, BC2F1 and BC3F1 population, respectively, in the CAL1514 population, while it was 63.47 to 73.55, 78.16 to 88.76 and 83.96 to 91.81 percent in the BC1F1, BC2F1 and BC3F1 population, respectively, in the ZL153493 population. When the near-isogenic CMS lines of both populations are compared for agro-morphological traits with their recurrent parents, the agronomic qualities of recurrent parents, as well as the attributes of distinctness, uniformity and stability, are shown. Therefore, male sterility-transferred, female lines of RCRMH-2 and RCRMH-3 maize hybrids can be used directly to produce maize hybrid seed without the need of the detasseling process. [ABSTRACT FROM AUTHOR]

Lipid metabolism is critical for male reproduction in plants. Many lipid-metabolic genic male-sterility (GMS) genes function in the anther tapetal endoplasmic reticulum, while little is known about GMS genes involved in de novo fatty acid biosynthesis in the anther tapetal plastid. In this study, we identify a maize male-sterile mutant, enr1, with early tapetal degradation, defective anther cuticle, and pollen exine. Using genetic mapping, we clone a key GMS gene, ZmENR1, which encodes a plastid-localized enoyl-acyl carrier protein (ACP) reductase. ZmENR1 interacts with β-hydroxyacyl-ACP dehydratase (ZmHAD1) to enhance the efficiency of de novo fatty acid biosynthesis. Furthermore, the ZmENR1/ZmHAD1 complex is regulated by a Maize Male Sterility 1 (ZmMS1)-mediated feedback repression loop to ensure anther cuticle and pollen exine formation by affecting the expression of cutin/wax- and sporopollenin-related genes. Intriguingly, homologous genes of ENR1 from rice and Arabidopsis also regulate male fertility, suggesting that the ENR1-mediated pathway likely represents a conserved regulatory mechanism underlying male reproduction in flowering plants. Authors identify a genic male sterility gene, ZmENR1, in maize and report that it encodes an enoyl carrier protein reductase that forms heterodimers with ZmHAD1 to ensure maize pollen and anther development through regulating lipid and ROS metabolism. [ABSTRACT FROM AUTHOR]

Background: Cytoplasmic male sterility (CMS) and its restoration of fertility (Rf) system is an important mechanism to produce F1 hybrid seeds. Understanding the interaction that controls restoration at a molecular level will benefit plant breeders. The CMS is caused by the interaction between mitochondrial and nuclear genes, with the CMS phenotype failing to produce functional anthers, pollen, or male gametes. Thus, understanding the complex processes of anther and pollen development is a prerequisite for understanding the CMS system. Currently it is accepted that the Rf gene in the nucleus restores the fertility of CMS, however the Rf gene has not been cloned. In this study, CMS line 8A and the Rf line R1, as well as a sterile pool (SP) of accessions and a restorer pool (RP) of accessions analyzed the differentially expressed genes (DEGs) between CMS and its fertility restorer using the conjunction of RNA sequencing and bulk segregation analysis. Results: A total of 2274 genes were up-regulated in R1 as compared to 8A, and 1490 genes were up-regulated in RP as compared to SP. There were 891 genes up-regulated in both restorer accessions, R1 and RP, as compared to both sterile accessions, 8A and SP. Through annotation and expression analysis of co-up-regulated expressed genes, eight genes related to fertility restoration were selected. These genes encode putative fructokinase, phosphatidylinositol 4-phosphate 5-kinase, pectate lyase, exopolygalacturonase, pectinesterase, cellulose synthase, fasciclin-like arabinogalactan protein and phosphoinositide phospholipase C. In addition, a phosphatidylinositol signaling system and an inositol phosphate metabolism related to the fertility restorer of CMS were ranked as the most likely pathway for affecting the restoration of fertility in pepper. Conclusions: Our study revealed that eight genes were related to the restoration of fertility, which provides new insight into understanding the molecular mechanism of fertility restoration of CMS in Capsicum. [ABSTRACT FROM AUTHOR]

In the present paper, we evaluated the implementation of a seed production system based on the exploitation of male sterility on coffee. We studied specifically the combination between CIR-SM01 and Marsellesa® (a Sarchimor line), which provides a hybrid population called Starmaya. We demonstrated that the establishment of seed garden under natural pollination is possible and produces a sufficient amount of hybrid seeds to be multiplied efficiently and economically. As expected for F1 hybrid, the performances of Starmaya are highly superior to conventional cultivars. However, we observed some heterogeneity on Starmaya cultivar in the field. We confirmed by genetic marker analysis that the off-types were partly related to the heterozygosity of the CIR-SM01 clone and could not be modified. Regarding the level of rust resistance of Starmaya cv., we saw that it could be improved if Marsellesa was more fully fixed genetically. If so, we should be able to decrease significantly the percentage of rust incidence of Starmaya from 15 to 5%, which would be quite acceptable at a commercial level. Starmaya represents the proof of concept for the mass propagation of Arabica F1 hybrid seeds using male sterility. Finally, we discuss the possibility to increase the number of hybrid varieties produced by seed, exploring some initiatives to identify male sterility markers to induce male sterility on any conventional cultivar. This would definitively open up the universe of known Arabica cultivars to be used in breeding new F1 hybrids. [ABSTRACT FROM AUTHOR]

The performance of first‐generation hybrids determines to a large extent the long‐term outcome of hybridization in natural populations. F1 hybrids can facilitate further gene flow between the two parental species, especially in animal‐pollinated flowering plants. We studied the performance of reciprocal F1 hybrids between Rhinanthus minor and R. major, two hemiparasitic, annual, self‐compatible plant species, from seed germination to seed production under controlled conditions and in the field. We sowed seeds with known ancestry outdoors before winter and followed the complete life cycle until plant death in July the following season. Germination under laboratory conditions was much lower for the F1 hybrid formed on R. major compared with the reciprocal hybrid formed on R. minor, and this confirmed previous results from similar experiments. However, this difference was not found under field conditions, which seems to indicate that the experimental conditions used for germination in the laboratory are not representative for the germination behaviour of the hybrids under more natural conditions. The earlier interpretation that F1 hybrid seeds formed on R. major face intrinsic genetic incompatibilities therefore appears to be incorrect. Both F1 hybrids performed at least as well as and sometimes better than R. minor, which had a higher fitness than R. major in one of the two years in the greenhouse and in the field transplant experiment. The high fitness of the F1 hybrids confirms findings from naturally mixed populations, where F1 hybrids appear in the first year after the two species meet, which leads to extensive advanced‐hybrid formation and introgression in subsequent generations. [ABSTRACT FROM AUTHOR]

Abstract: In Brassica oleracea, production of F1 hybrid seeds mainly makes use of the improved Ogura cytoplasmic male sterile (CMS) line. However, reliance on one particular line is a risk, and it would be advantageous to develop other CMS lines. In this study, we transferred Diplotaxis erucoides cytoplasm to B. oleracea cultivars using an alloplasmic B. rapaCMS line as a bridge plant to avoid incompatibility between donor and recipient plants. The new B. oleraceaCMS lines, which were derived by four generations of backcrossing, had small rudimentary anthers with no pollen grain and showed complete male sterility. There was no functional defect in other floral organs, and the ability to receive normal pollen did not appear to be impaired. Moreover, the B. oleraceaCMS lines carrying D. erucoides cytoplasm had larger leaf areas and a normal plastochron. As a consequence, the B. oleraceaCMS lines carrying D. erucoides cytoplasm have the potential to be valuable alternatives for use in commercial B. oleracea hybrid seed production. [ABSTRACT FROM AUTHOR]