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Twenty-one quantitative trait loci were discovered across six environments, including three (NS), seven (LS) and eleven (VLS) conditions. The linkage groups 1A, 1B, 2A, 2B, 2D, 3B, 4A, 6A, 6B and 7D spanned quantitative trait loci (QTLs). For canopy temperature (CT), a stable QTL (Qct_rpcau_4A) in the environment E6 has shown a phenotypic variance (PVE) up to 17.85%. The QTL, Qspad_rpcau_2D, was found to be stable for SPAD value, explaining the PVE of 15.05%. Whereas, three stable QTLs viz. Qgy_rpcau_3B, Qgy_rpcau_4A and Qgy_rpcau_6A were associated with the chromosomes 3B, 4A and 6B explaining a PVE of 20.85%, 17.43% and 17.37% respectively for the trait GY. The interaction of genotype and environment has been shown to be useful in determining the best lines for heat-stressed environments. In addition, G X E analysis was performed on the population. In the ranking of genotypes for both mean yield and mean vs. stability, GGE biplot across the six environments, DH 146, 195, 60, 202, 65, 155, 124, 5, 201, 169, 15 and 170 were ranked closest to ideal and winning genotype; these were highly adapted and most stable lines. The goal of the current investigation was to find the best suitable double haploid lines which can withstand heat stress and to find those QTLs which are influential to heat stress for the studied traits. [ABSTRACT FROM AUTHOR]

Breeders are turning to rapid breeding methods in order to respond to the increasing population for the breeding of the wheat plant, which has a very important place in human nutrition. One of the biotechnological methods to shorten wheat breeding, which takes 15-20 years with classical breeding methods, is double haploid. The aim of this study is to obtain double haploid lines by taking wheat genotypes that have reached the F2 generation after hybridization into anther culture and thus shorten the breeding period. When looking at the response to anther culture of the 15 different F2 combinations used in the study, F2-7 and F2-10 genotypes stood out as the most successful genotypes. It was observed that 4 different groups were formed among 15 genotypes according to the success rate. It was concluded that the success of anther culture varies depending on the genotypes used, the nutrient media and the suitability of laboratory conditions. [ABSTRACT FROM AUTHOR]

Rapeseed is a significant global source of plant oil. Silique size, particularly silique length (SL), impacts rapeseed yield. SL is a typical quantitative trait controlled by multiple genes. In our previous study, we constructed a DH population of 178 families known as the 158A-SGDH population. In this study, through SL QTL mapping, we identified twenty-six QTL for SL across five replicates in two environments. A QTL meta-analysis revealed eight consensus QTL, including two major QTL: cqSL.A02-1 (11.32–16.44% of PVE for SL), and cqSL.C06-1 (10.90–11.95% of PVE for SL). Based on biparental resequencing data and microcollinearity analysis of target regions in Brassica napus and Arabidopsis, we identified 11 candidate genes at cqSL.A02-1 and 6 candidate genes at cqSL.C06-1, which are potentially associated with silique development. Furthermore, transcriptome analysis of silique valves from both parents on the 14th, 21st, and 28th days after pollination (DAP) combined with gene function annotation revealed three significantly differentially expressed genes at cqSL.A02-1, BnaA02G0058500ZS, BnaA02G0060100ZS, and BnaA02G0060900ZS. Only the gene BnaC06G0283800ZS showed significant differences in parental transcription at cqSL.C06-1. Two tightly linked insertion-deletion markers for the cqSL.A02-1 and cqSL.C06-1 loci were developed. Using these two QTL, we generated four combinations: A02SGDH284C06158A, A02SGDH284C06SGDH284, A02158AC06158A, and A02158AC06SGDH284. Subsequent analysis identified an ideal QTL combination, A02158AC06SGDH284, which exhibited the longest SL of this type, reaching 6.06 ± 0.10 cm, significantly surpassing the other three combinations. The results will provide the basis for the cloning of SL-related genes of rapeseed, along with the development of functional markers of target genes and the breeding of rapeseed varieties. [ABSTRACT FROM AUTHOR]

The production of double haploids ("DH") by microspore-derived embryos is one of the best breeding methods to generate new varieties with better traits and stable genetic background. In the previous study, radish 'DH' lines were generated with a different range of glucosinolate (GSL) contents, ranging from low to high levels of GSL. In this study, we performed metabolic and transcriptional profiling to elucidate the regulatory system behind the GSL biosynthesis process using the 'DH' radish lines. Four individual 'DH' lines were selected, of which two lines named 'HH' had high GSL content, while the other two lines, 'LL', had low GSL content. HPLC analysis in the vegetative (leaf and root) and reproductive tissue (seed) was detected seven GSL compounds from radish. Among seven GSLs, glucoraphasatin (GRH) occupied the largest proportion of total GSLs in both leaf and root tissues, while glucoraphenin (GRE) was taking a place as the major GSL in radish seeds. Six major genes (RsBCAT4, RsIPMDH1, RsCYP79F1, RsCYP83A1, RsUGT74B1, and RsGRS1) representing the major biosynthesis of aliphatic GSLs were selected for qRT-PCR analysis. Heat map analysis based on Pearson correlation coefficient showed that RsBCAT4, RsIPMDH1, RsCYP79F1, and RsCYP83A1 were positively correlated with the amount of GRH in leaf tissue. Meanwhile, RsGRS1 showed a strong correlation with the amount of GRH and total aliphatic GSLs in both leaf and root tissues. By using the 'DH' radish lines, this study revealed that regardless of tissues of radish, accumulation of total GSL is strongly affected by the RsGRS1 and also positively supported by the other biosynthetic genes like RsBCAT4, RsIPMDH1, RsCYP79F1, and RsCYP83A1. [ABSTRACT FROM AUTHOR]

Sweetpotato (Ipomoea batatas L.) is a strategic crop with both economic and energy value. However, improving sweetpotato varieties through traditional breeding approaches can be a time-consuming and labor-intensive process due to the complex genetic nature of sweetpotato as a hexaploid species (2n = 6x = 90). Double haploid (DH) breeding, based on in vivo haploid induction, provides a new approach for rapid breeding of crops. The success of haploid induction can be achieved by manipulating specific genes. Two of the most critical genes, DMP (DUF679 membrane proteins) and MTL (MATRILINEAL), have been shown to induce haploid production in several species. Here, we identified and characterized DMP and MTL genes in sweetpotato using gene family analysis. In this study, we identified 5 IbDMPs and 25 IbpPLAs. IbDMP5 and IbPLAIIs (IbPLAIIκ, IbPLAIIλ, and IbPLAIIμ) were identified as potential haploid induction (HI) genes in sweetpotato. These results provide valuable information for the identification and potential function of HI genes in sweetpotato and provide ideas for the breeding of DH lines. [ABSTRACT FROM AUTHOR]

To keep pace with the skyrocketing demand of vegetable oil and reduced dependency on import, there is a need to focus on indigenous oilseed crops, such as niger (Guizotia abyssinica L.F. Cass). Niger is a minor oilseed crop that consists of 32 to 40% quality oil and 18 to 24% protein in the seeds. Despite its considerable importance, self-incompatibility and high outcrossing pose difficulty in breeding through conventional methods. Double haploid (DH) technology is one of the alternatives to overcome the problem and develop inbred lines in a shorter time. In context to this, a highly efficient protocol for DH production through anther culture in Indian niger varieties JNS 9 and JNS 28 was developed. The investigation was conducted to identify the suitable microspore stage for anther culture, cold pre-treatment, hormonal combinations for callus induction (T1–T4), shooting (S1–S26), rooting (R1–R3), hardening, ploidy index, and the effect of different colchicine treatments on the efficiency of the developed protocol. Anthers in disc florets of light green to greenish yellow color have uninucleate microspores (7 d of bud initiation). For callus initiation, Murashige and Skoog (MS) medium containing 2.0 mg L−1 2,4-dichlorophenoxyacetic acid (2,4-D) and 0.3 mg L−1 kinetin (KIN) showed 100% efficiency. For shoot initiation, 37 to 40% greening was observed on MS medium with 0.5 mg L−1 6-benzylaminopurine (BAP) and 0.5 mg L−1 activated charcoal and, subsequently, 19% shoot emergence on MS medium containing 0.5 mg L−1 BAP and 0.5 mg L−1 KIN. Low efficiency of shoot regeneration was addressed by adding 0.2% colchicine for 30 h at the callusing stage which resulted in 90 to 95% increased efficiency in shooting. For rooting, MS medium containing 2.0 mg L−1 indole-3-butyric acid (IBA) was efficient with a frequency of 85 to 90% followed by hardening in 1:1:1 ratio of vermiculite:sand:soil in pots. Ploidy indexing was done using cell size analysis followed by chromosome count using a microscope which confirmed the ploidy level of regenerants as compared to diploid control. Thus, the procedure developed in the study demonstrates the successful development of DH which in turn facilitates the acceleration of the breeding program through the development of homozygous inbreds and new cultivars. [ABSTRACT FROM AUTHOR]

The maize breeding programs focuses on the development of homozygous parental lines for hybrid breeding to obtain heterosis. The Improvement of homozygous lines in a effective time is crucial for hybrid maize breeding. Objectives of this research were to obtain homozygous lines of maize in a short time by using of in-vivo maternal haploid (DH) technique and characterizing them morphologically. The experiments were carried out at the Eastern Mediterranean Agricultural Research Institute(EMARI). Inducers, RWS, RWK-76 and their hybrid RWS X RWK-76 were used as male parent. As female parent, 56 F2 segregated material obtained by selfing of 66 F1 hybrids developed in maize breeding program of Eastern Mediterranean Agricultural Research Institute (EMARI) and 2 F2 segregated material selected from the open pollinated plants of 9 commercial maize variety. As a result of the experiment, 29 doubled haploid lines (DH) were developed. In the developed DH lines, days to tasseling, plant height, height of first ear , ear length, ear diameter, number of kernel per ear and thousand kernel weight varied as 57-78 days, 151-248 cm, 43-112 cm, 11.20-24.50 cm, 24-45 mm, 224-537 kernels/ear, and 180-320 g, respectively. In conclusion, in-vivo maternal DH technique is a highly effective method for obtaining homozygous lines

[Objectives]The paper aimed to obtain double haploids of the melon (2n=2x=24) inbred line BPC-4 by distant hybridization, and analyse botanical traits and genomic changes. [Methods]The melon inbred line BPC-4 was used as the maternal parent to cross with eight different materials of the genus Cucumis. F1 generation of the obtained cross was selfed to obtain F2 and F3,which were used for chromosome number observation, SSR molecular marker analysis and plant traits consistency in the same generation to identify their double haploid feature; F2 and F3 were genome resequenced and then purified site distribution and stability of double haploid genome SNP were analyzed. [Results]Among the eight hybrid combinations, three seeds were obtained from the combination of (BPC-4×cucumber inbred line YPJ-6) (2n=2x=14),among which one seed was planted and 50 self-crossing progenies were obtained. The chromosome number of the F2 generation were identified to be 2n=2x=24. SSR identification showed that the PCR bands by 27 SSR markers in F2 generation were the same as those of the maternal parent. The PCR bands of F2 was consistent among single plants and F3 was not separated, indicating that the F2 gene loci were homozygous. Statistical analysis of botanical traits showed that the main changes in F2 were compact and dwarf compared with BPC-4. The average values of internode spacing, stem diameter, leaf length and width, and petiole length in F2 were all lower than those of BPC-4,and F2 individual plants were consistent. The above results proved that the progenies obtained from the distant crosses were double haploid, and thus F1,F2 and F3 were named as DH0,DH1 and DH2,respectively. The data of seed number and seed setting rate of dihaploid showed that fertility of DH0 was low, while fertility of DH1 and DH2 had recovered up to that of BPC-4 and could be used for seed propagation and preserved through self-crossing. The genome resequencing revealed that the double haploid SNP loci were further purified by 0.26% compared with BPC-4,and the new purified loci were distributed on all 12 chromosomes. The difference of purified loci between DH1 and DH2 of the double haploid selfing progeny was 1 016,accounting for only 0.05%,which was smaller than the heterozygosity difference of 3.13% from Mendelian theory conventional self-crossing S4 to S5,indicating that the double haploid genome had been stabilized. [Conclusions]Genome resequencing and botanical trait variation demonstrated that it was still necessary to create a double haploid in melon after four generations of self-crossing, and that the double haploids obtained could be saved by seed for further breeding and theoretical studies.  [ABSTRACT FROM AUTHOR]

Zinc (Zn) deficiency is a common limiting factor in agricultural soils, which leads to significant reduction in both the yield and nutritional quality of agricultural produce. Exploring the quantitative trait loci (QTL) for shoot and grain Zn accumulation would help to develop new barley cultivars with greater Zn accumulation efficiency. In this study, two glasshouse experiments were conducted by growing plants under adequate and low Zn supply. From the preliminary screening of ten barley cultivars, Sahara (0.05 mg/pot) and Yerong (0.06 mg/pot) showed the lowest change in shoot Zn accumulation, while Franklin (0.16 mg/pot) had the highest change due to changes in Zn supply for plant growth. Therefore, the double haploid (DH) population derived from Yerong × Franklin was selected to identify QTL for shoot mineral accumulation and biomass production. A major QTL hotspot was detected on chromosome 2H between 31.91 and 73.12 cM encoding genes for regulating shoot mineral accumulations of Zn, Fe, Ca, K and P, and the biomass. Further investigation demonstrated 16 potential candidate genes for mineral accumulation, in addition to a single candidate gene for shoot biomass in the identified QTL region. This study provides a useful resource for enhancing nutritional quality and yield potential in future barley breeding programs. [ABSTRACT FROM AUTHOR]

Bounteous modern and innovative biotechnological tools have resulted in progressive development in the barley breeding program. Doubled haploids developed (homozygous lines) in a single generation is significant. Since the first discovery of haploid plants in 1920 and, in particular, after discovering in vitro androgenesis in 1964 by Guha and Maheshwari, the doubled haploidy techniques have been progressively developed and constantly improved. It has shortened the cultivar development time and has been extensively used in: genetic studies, gene mapping, marker/trait association, and QTL studies. In barley, the haploid occurrence developed gradually from being a sporadic and random process (spontaneous) to haploid development by in vivo method of modified pollination or by in vitro culture of immature male or female gametophytes. Although significant improvement in DH induction protocols has been made, challenges still exist for improvement in areas such as: low efficiency, albinism, genotypic specificity etc. Here, the paper focuses on: haploidization via different in vitro, in vivo techniques, the recent advances technologies like centromere‐mediated haploidization, hap induction gene, and Doubled haploid CRISPR. The au-courant work of different researchers in barley using these technologies is reviewed. Studies on different factors affecting haploid induction and work on genome doubling of barley haploids to produce DH lines via spontaneous and induced technologies has also been highlighted. [ABSTRACT FROM AUTHOR]

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Double haploids (DHs) production and utilization is an important aspect of wheat breeding programs in worldwide, because, it provides many advantages over the conventional breeding program. Therefore, in vitro and in vivo responses of anther derived two bread wheat cultivars and their F1 crosses were investigated. Results showed significant genetic variation among the tested bread wheat genotypes. The pre-cold treated anther derived embryonic calli and shoot induction (%) were obtained from all genotypes that ranged 44 - 76% and 32 - 58% respectively. The highest shoot induction from embryonic calli was achieved from F1 cross of Zubkov x Atay-85, whereas, lowest induction was obtained from Atay-85 cultivar. The F1 cross (Zubkov x Atay-85) showed a better response in anther culture in term of shoots per plant and root induction than their respective parental genotypes.The present results indicated positive and significant heterotic effects of F1 crosses for calli and shoot induction that also showed less albino plant regeneration after colchicine treatments. Total number of 114 anthers driven DHs lines from two genotypes and their F1 crosses were regenerated, confirmed by flow-cytometry and evaluated under field condition. Some DHs lines were found to be significantly superior for agronomical traits including seed yield than the parental genotypes as well as local bread wheat (control) cultivars.

Maize (Zea mays) hybrid breeding programs are increasingly adopting double haploid (DH) technology to enhance efficiency and meet the growing demand for food in the face of population growth and climate change. However, in developing countries such as those in subtropical regions, the utilization of DH technology is still limited. This study aims to evaluate the potential benefits of incorporating this technology into both new and established maize breeding programs. Using a pedigree selfing population from the CIMMYT Genebank, DH lines were developed and compared to the conventional pedigree selfing method through a line-by-tester evaluation. Fifteen DH lines and fourteen lines from each of the S2, S4, and S6 selfing generations were subjected to multilocation yield trials in the subtropics of Mexico. The results showed that it took three years for the S1 population to identify DH lines with 100 % homozygosity and the highest general combining ability (GCA), which was one year earlier than the S6 lines (98,4 % homozygous). DH lines exhibited more genotype-by-environment interactions (GxE) compared to S2 testcrosses but demonstrated similar heritability to the S6 generation. Significant statistical differences were observed between the DH evaluations and the S4 and S6 testcrosses, while no significant difference was found between the S2 and DH evaluations. Based on these findings, a gradual implementation of DH technology in hybrid breeding programs is recommended. However, the conventional pedigree method should not be abandoned entirely, and testing in selfing generations, particularly in S6, remains crucial. This study provides a statistical comparison of DH versus the conventional pedigree method using a line-by-tester approach, contributing valuable insights for plant breeders and researchers in the field of maize breeding. [ABSTRACT FROM AUTHOR]

Ovule number (ON) produced during flower development determines the maximum number of seeds per silique and thereby affects crop productivity; however, the genetic basis of ON remains poorly understood in oilseed rape (Brassica napus). In this study, we genetically dissected the ON variations in a double haploid (DH) population and in natural population (NP) by linkage mapping and genome-wide association analysis. Phenotypic analysis showed that ON displayed normal distribution in both populations with the broad-sense heritability of 0.861 (DH population) and 0.930 (natural population). Linkage mapping identified 5 QTLs related to ON, including qON-A03, qON-A07, qON-A07-2, qON-A10, and qON-C06. Genome-wide association studies (GWAS) revealed 214, 48, and 40 significant single-nucleotide polymorphisms (SNPs) by individually using the single-locus model GLM and the multiple-locus model MrMLM and FASTMrMLM. The phenotypic variation explained (PVE) by these QTLs and SNPs ranged from 2.00–17.40% to 5.03–7.33%, respectively. Integration of the results from both strategies identified four consensus genomic regions associated with ON from the chromosomes A03, A07, and A10. Our results preliminarily resolved the genetic basis of ON and provides useful molecular markers for plant yield improvement in B. napus. [ABSTRACT FROM AUTHOR]

The development of Fusarium head blight (FHB)-resistant winter wheat cultivars using the gene Fhb1 has been conducted in northern China. Sumai 3, a Chinese FHB-resistant spring wheat cultivar, carries three FHB resistance genes: Fhb1, Fhb2 and Fhb5. To better use these genes for increasing FHB resistance in northern China, it is necessary to elucidate the pyramiding effects of Fhb1, Fhb2 and Fhb5 in winter wheat backgrounds. Eight gene combinations involving Fhb1, Fhb2 and Fhb5 were identified in a double haploid (DH) population, and the effects on FHB resistance were evaluated in six tests. At the single gene level, Fhb1 was more efficient than the other two genes in single-floret inoculation tests, whereas Fhb5 showed better resistance than Fhb1 and Fhb2 under a natural infection test. Pyramiding Fhb1, Fhb2 and Fhb5 showed better FHB resistance than the other gene combinations. Forty-nine DH lines showing consistently better resistance than the moderately susceptible control Huaimai 20 in multiple tests were evaluated for main agronomic traits, and no difference in grain yield was found between the mean values of DH lines and the recipient parents Lunxuan 136 and Lunxuan 6, which are higher than those of recipient parent Zhoumai 16 and the donor parent Sumai 3 (p < 0.05). Based on the phenotypic and genomic composition analyses, five promising DH lines fully combined the FHB resistance of donor Sumai 3 and the elite agronomic traits from the recipient parents. This study elucidates the pyramiding effects of three FHB resistance genes and that the promising DH lines with resistance to FHB can be directly applied in wheat production or as parents in winter wheat breeding programs. [ABSTRACT FROM AUTHOR]

The DH lines derived from PBW343 × IC252478 were sown for three distinct sowing dates for the years 2017–2018 and 2018–2019. The area chosen for this study was chosen because it is a hot spot for wheat production, and heat stress is a major limitation for wheat growers. In this study, three replicates of the alpha lattice design were employed. Stability measures and genotype–environment interaction were shown to be valuable methods in determining the best lines for heat-stressed environments. Out of 165 DH lines, DH 71, DH 150, DH 34, DH13 DH 64, DH 138, DH 98, DH 84, DH 62, DH 104, DH 74, DH 3, DH 104, DH 107, and DH 156 were ranked closest to ideal and winning genotype in the ranking of genotypes for mean yield, mean versus stability, GGE biplot, and stability performance across the six environments; these were highly adapted, most stable, heat-tolerant, and high-yielding lines. Moreover, the population was also subjected to quantitative trait loci (QTL) mapping for which composite interval mapping (CIM) was performed and it unravelled a total of 36 QTLs where 6 QTLS were detected in non-stressed and 30 QTLs in heat-stressed condition. The detected QTLs spanned on 1A, 1D, 2B, 2D, 3B, 4D, 5B, and 6D chromosomes. The overall goal of the current investigation was to find the best suitable double haploid lines which can withstand heat stress and to find those QTLs which are influential to heat stress for yield-related traits. [ABSTRACT FROM AUTHOR]

Zinc (Zn) deficiency is a common limiting factor in agricultural soils, which leads to significant reduction in both the yield and nutritional quality of agricultural produce. Exploring the quantitative trait loci (QTL) for shoot and grain Zn accumulation would help to develop new barley cultivars with greater Zn accumulation efficiency. In this study, two glasshouse experiments were conducted by growing plants under adequate and low Zn supply. From the preliminary screening of ten barley cultivars, Sahara (0.05 mg/pot) and Yerong (0.06 mg/pot) showed the lowest change in shoot Zn accumulation, while Franklin (0.16 mg/pot) had the highest change due to changes in Zn supply for plant growth. Therefore, the double haploid (DH) population derived from Yerong × Franklin was selected to identify QTL for shoot mineral accumulation and biomass production. A major QTL hotspot was detected on chromosome 2H between 31.91 and 73.12 cM encoding genes for regulating shoot mineral accumulations of Zn, Fe, Ca, K and P, and the biomass. Further investigation demonstrated 16 potential candidate genes for mineral accumulation, in addition to a single candidate gene for shoot biomass in the identified QTL region. This study provides a useful resource for enhancing nutritional quality and yield potential in future barley breeding programs.

Anther culture technique is one of the commonly used method in order to obtain haploid plants in eggplant. It is known that androgenic response in eggplant is variable and one of the most important factors determining success is the genotype effect. Low or insufficient embryogenic response limits the use of doubled haploid technology in breeding programs. Therefore, determining the embryogenic responses of genotypes is a step for the use of this technology in breeding studies. In this study, 61 eggplant genotypes at various breeding stages (F1, F2, and F3) in the gene pool of United Genetics Vegetable Seeds Company (Mustafakemalpaşa, Bursa, Turkey) were evaluated in terms of androgenic responses. Significant differences were determined among eggplant genotypes in terms about embryo induction and conversion rates of embryos to full plantlets. In the study, responsiveness to anther culture based on genotype ranged from 0.0%-21.58%. The conversion rate of induced embryos to plants varied between 0.0% and 100%. [ABSTRACT FROM AUTHOR]

Double haploids (DHs) production and utilization is an important aspect of wheat breeding programs in worldwide, because, it provides many advantages over the conventional breeding program. Therefore, in vitro and in vivo responses of anther derived two bread wheat cultivars and their F1 crosses were investigated. Results showed significant genetic variation among the tested bread wheat genotypes. The pre-cold treated anther derived embryonic calli and shoot induction (%) were obtained from all genotypes that ranged 44 - 76% and 32 - 58% respectively. The highest shoot induction from embryonic calli was achieved from F1 cross of Zubkov x Atay-85, whereas, lowest induction was obtained from Atay-85 cultivar. The F1 cross (Zubkov x Atay-85) showed a better response in anther culture in term of shoots per plant and root induction than their respective parental genotypes. The present results indicated positive and significant heterotic effects of F1 crosses for calli and shoot induction that also showed less albino plant regeneration after colchicine treatments. Total number of 114 anthers driven DHs lines from two genotypes and their F1 crosses were regenerated, confirmed by flow-cytometry and evaluated under field condition. Some DHs lines were found to be significantly superior for agronomical traits including seed yield than the parental genotypes as well as local bread wheat (control) cultivars. [ABSTRACT FROM AUTHOR]

Combination breeding and mutation breeding are widely used methods in plant breeding. Intensive studies are carried out on biotechnological methods that will allow obtaining homozygous lines in a short time in populations obtained with these two techniques. Numerous studies have been carried out by different researchers on mutation breeding in wheat. There are few studies on anther culture response in mutagen-treated genotypes. Two different bread wheat promising advanced lines were used as the material in the study, in which the possibilities of combining mutation breeding with anther culture through ionizing radiation in high quality wheat breeding were investigated. In the study, the responses of advanced bread wheat mutant lines to anther culture, to which eight different doses of gamma rays (0, 100, 150, 200, 250, 300, 350, 400 Gy) were applied, including the control, were investigated. There are significant differences between genotypes and irradiation doses for all traits studied. It has been shown that it is possible to decrease albinism and increase the response of anther culture with dose-dependent gamma irradiation depending on bread wheat varieties. In the multiple comparison test to classify the difference between doses; statistically, 150 gray dose 5.60 is in the first statistical class and in the first place with the number of transferred green plants. After that, it ranks second in the same class with the number of green plants transferred with a 300 gray dose of 5.21. In the total number of regenerated green plants excluding controls (888), 635 unit (71.5%) and 205 unit (23.1%) haploids and spontaneous double haploid plants were obtained, respectively. In the study integrated into the bread wheat breeding program, a total of 205 spontaneous double haploid mutant lines were produced. According to the data obtained, it was shown that the gamma ray doses of 150 and 200 Gy had a significant stimulation effect on all parameters studied and ultimately the success index of anther culture in bread wheat compared to control. [ABSTRACT FROM AUTHOR]

Summary: Reactive oxygen species (ROS) play important roles during anther and pollen development. DNA damage may cause chromosome fragmentation that is considered to underlie chromosome elimination for haploid induction by matrilineal pollen, a key step in MATRILINEAL‐based double haploid breeding technology. But when and how DNA damage occurs is unknown.We performed comparative studies of wheat pollens from the wild‐type and the CRISPR/Cas9 edited matrilineal mutant (mMTL).Chemical assays detected a second wave of ROS in mMTL pollen at the three‐nuclei‐stage and subsequently, along with reduced antioxidant enzyme activities. RNA‐seq analysis revealed disturbed expression of genes for fatty acid biosynthesis and ROS homoeostasis. Gas chromatography‐mass spectrometry measurement identified abnormal fatty acid metabolism that may contribute to defective mMTL pollen walls as observed using electron microscopy, consistent with the function of MTL as a phospholipase. Moreover, DNA damage was identified using TdT‐mediated dUTP nick‐end labelling and quantified using comet assays. Velocity patterns showed that ROS increments preceded that of DNA damage over the course of pollen maturation.Our work hypothesises that mMTL‐triggered later‐stage‐specific ROS causes DNA damage that may contribute to chromosome fragmentation and hence chromosome elimination during haploid induction. These findings may provide more ways to accelerate double haploid‐based plant breeding. [ABSTRACT FROM AUTHOR]

Abstract Background Farmed Atlantic salmon are one of the most economically significant global aquaculture products. Early sexual maturation of farmed males represents a significant challenge to this industry and has been linked with the vgll3 genotype. However, tools to aid research of this topic, such as all-male and clonal fish, are still lacking. The present 6-year study examined if all-male production is possible in Atlantic salmon, a species with heteromorphic sex chromosomes (males being XY, females XX), and if all-male fish can be applied to further explore the vgll3 contribution on the likelihood of early maturation. Results Estrogen treatment of mixed sex yolk sac larvae gave rise to one sexually mature hermaphrodite with a male genotype (XY) that was used to produce both self-fertilized offspring and androgenetic double haploid (dh) offspring following egg activation with UV treated sperm and pressure shock to block the first mitotic division. There were YY supermales among both offspring types, which were crossed with dh females. Between 1 and 8% of the putative all-male offspring from the eight crosses with self-fertilized supermales were found to have ovaries, and 95% of these phenotypic females were also genetically female. None of the offspring from the one dh supermale cross had ovaries. When assessing the general contribution of the vgll3 locus on the likelihood of early post-smolt sexual maturation (jacking) in the all-male populations we found individuals that were homozygous for the early maturing genotype (97%) were more likely to enter puberty than individuals that were homozygous for the late maturing genotype (26%). However, the likelihood of jacking within individuals with an early/late heterozygous genotype was higher when the early allele came from the dam (94%) compared to the sire (45%). Conclusions The present results show that supermale Atlantic salmon are viable and fertile and can be used as a research tool to study important aspects of sexual maturation, such as to further explore the sex dependent parental genetic contribution to age at puberty in Atlantic salmon. In addition, we report the production of viable double haploid supermale fish.

To facilate breeding process of Brassica napus, a microspore culture and molecular marker-assisted screening combined system were proposed in this research. At early flowering stage, F1 offspring of hybridized combination HY15A ​× ​HF06 was used as donor for microspore culture to analyze effects of colchicine concentration on embryogenic and diploid rates of microspore. Treatment with 50 ​mg/L colchicine resulted in embryogenic rate of 3.56 embryos/bud, which was substantially higher than control (0.78 embryos/bud). A total of 1,387 embryos and 862 single plants were obtained after induction culture. Ploidy detection was performed for the regenerated plants by flow cytometry. Diploid rates of microspores treated with 50 ​mg/L and 70 ​mg/L colchicine were 17.2% and 21.0% respectively, which was significantly higher than control (10.5%). Totally 108 single plants that doubled successfully were randomly selected and screened using molecular marker BE10. Approximately 54 of 108 plants generated a 305 bp amplification product, whereas the other 54 plants showed a 398 bp band, thereby satisfying 1:1 separation ratio (x20.05 ​= ​0.0093). These coincided with field identification results. Findings of this study indicated that homozygous breeding material could be obtained by microspore culture in a short time, thereby remarkably accelerate breeding.

The golden berry Physalis peruviana native to the inter-Andean valleys of South America, is currently one of the most relevant exotic fruits for Colombia, its demand for export seeks to possess ideal traits of yield and fruit quality. The objective is to determine the genetic parameters of Combinatory Aptitude of nine inbred lines of Uchuva under conditions of the Andean natural region of the department of Nariño. 36 hybrids of cape gooseberry obtained from nine inbred lines 12U347, 12U350, 12U352, 12U357, 12U360, 12U368, 12U374, 12U377, and 12U39, in four localities of the department of Nariño: Gualmatán, Puerres, Pasto, and Ipiales, in order to determine the effects of general (GCA) and specific (SCA) combining ability on performance. The commercial yield (CY) and the agronomic yield (AY) are evaluated in a dialellic under method IV of Griffing (1956). The combined analysis of variation indicates significant differences in the genotype-environment interaction for CY and AY across all localities. The Combinatorial Aptitude analysis reported that additive and nonadditive effects are important in AY and CY. The best hybrids in Gualmatán were 7x8, 3x5 and 3x7, in Ipiales 2x9, 1x3 and 4x8, in Pasto 1x7, 1x3 and 7x8, and in Puerres 2x5, 2x8 and 2x3, which can be taken into account to be used as commercial hybrids high yield. [ABSTRACT FROM AUTHOR]

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.)

The development of Fusarium head blight (FHB)-resistant winter wheat cultivars using the gene Fhb1 has been conducted in northern China. Sumai 3, a Chinese FHB-resistant spring wheat cultivar, carries three FHB resistance genes: Fhb1, Fhb2 and Fhb5. To better use these genes for increasing FHB resistance in northern China, it is necessary to elucidate the pyramiding effects of Fhb1, Fhb2 and Fhb5 in winter wheat backgrounds. Eight gene combinations involving Fhb1, Fhb2 and Fhb5 were identified in a double haploid (DH) population, and the effects on FHB resistance were evaluated in six tests. At the single gene level, Fhb1 was more efficient than the other two genes in single-floret inoculation tests, whereas Fhb5 showed better resistance than Fhb1 and Fhb2 under a natural infection test. Pyramiding Fhb1, Fhb2 and Fhb5 showed better FHB resistance than the other gene combinations. Forty-nine DH lines showing consistently better resistance than the moderately susceptible control Huaimai 20 in multiple tests were evaluated for main agronomic traits, and no difference in grain yield was found between the mean values of DH lines and the recipient parents Lunxuan 136 and Lunxuan 6, which are higher than those of recipient parent Zhoumai 16 and the donor parent Sumai 3 (p < 0.05). Based on the phenotypic and genomic composition analyses, five promising DH lines fully combined the FHB resistance of donor Sumai 3 and the elite agronomic traits from the recipient parents. This study elucidates the pyramiding effects of three FHB resistance genes and that the promising DH lines with resistance to FHB can be directly applied in wheat production or as parents in winter wheat breeding programs.

Background: Alfalfa (Medicago Sativa), a perennial cross-pollinated plant, is one of the most important forage crops in the world with commercial value and ecological significance. However, due to the complexity of its genome, varietal improvement is difficult. Therefore, generating genetically homozygous materials have greater significance for breeding. In the current study, we aimed to identify the best tissue culture conditions to obtain haploid plants and double haploid plants. Methods: In this study, the haploid plants of alfalfa were obtained by combining tissue culture regeneration system with Flow cytometry. Different concentrations of colchicine were applied to the haploid plants using solid and liquid cultivation methods to determine the optimum conditions to obtain double haploid plants of Medicago Sativa L. cv. 'XinJiangDaYe'. Result: Among the two colchicine cultivation methods tested, the doubling rate of regenerated plants obtained by liquid cultivation method was higher and the leaves developed under this system have the best doubling effect among the three explants tested. Optimal doubling conditions for alfalfa haploid (Medicago Sativa L. cv. 'XinJiangDaYe') were identified. The double haploid plant material generated from the current study could serve as a genetic resource for developing the hybrid combinations and for analyzing genetic linkage in alfalfa improvement programs. [ABSTRACT FROM AUTHOR]

For Russia countries with a temperate climate, with direct sowing of rice increase of cold tolerant varieties in seed germination and shoot formation are important. This trait allows to begin rice sowing earlier using for plant growing the favorable period by temperature to obtain optimum shoots by density that gives the chance to realize potential efficiency of varieties. A research objective is to create and estimate the initial stock resistant to low positive temperatures for use it for breeding of new cold tolerant rice varieties.Display of molecular markers - is neutral in relation to a phenotype and they can be found out at any stage of development of plants in ontogenesis. Methods of DNA-genotipirovanija and PCR analysis by means of molecular markers allow accelerating carrying over of the necessary genes in the course of breeding and to provide creation of new varieties with a complex of the set properties Therefore the role of biotechnological methods is important at creation new cold tolerant varieties.According to results of PCR analysis by use of SSR - marker lines of rice with dominant alleles of cold resistance genes were screened. Double haploids were obtained by anther culture method in vitro and resistant forms were found. Plants with economically valuable traits were screened. All-round evaluation of obtained material gave the possibility to find initial stock for use breeding process in future for release of new cold resistant rice varieties.

Breeding using the double haploid approach has been used in accelerating the rice breeding process. However, the main obstacle in the application of this technique in rice is the low level of callus formation and their regeneration into haploid plants. Based on these issues, this research is aimed at developing the best method for obtaining double haploid plants through anther culture using three kinds of aromatic rice of Indonesian local varieties. Anthers of Pendok, Genjah Arum, and Merah Wangi varieties were cultured in callus induction media which were either supplemented with different types of carbon sources, or auxins and ethylene inhibitors. However, the application of different sugar types did not significantly affect callus formation of Pendok and Genjah Arum. However, auxin treatment showed NAA to be more efficient for the callus induction of Pendok, while 2,4-D had no effect on callus induction in all tested varieties. The addition of ethylene inhibitor successfully induced callus formation of Merah Wangi varieties, while the rates of Pendok and Genjah Arum were not significantly affected. Callus of three plant lines were then regenerated into plantlet in regeneration media. Of the three callus varieties used, only Pendok could regenerate into plantlets and grow into adult haploid plants. [ABSTRACT FROM AUTHOR]

Identifying iron- and zinc-related quantitative trait loci (QTL) with consistent effects across environments and genetic backgrounds is necessary to develop rice varieties with high grain iron content (GIC) and grain zinc content (GZC). In this work, a doubled haploid population was developed through a cross between the Korean japonica cultivars Goami 2 and Hwaseonchal and phenotyped during the 2018 wet season (POP2018) and 2019 wet season (POP2019). The milled rice grains of POP2018 and POP2019 were used to identify GIC- and GZC-related QTL that was consistent between years. Digenic interactions and genes that affected GIC and GZC were also identified. Paired sample t test revealed that the GIC of POP2018 was not significantly different from that of POP2019 (t = 0.24, p =0.81), whereas the GZC of POP2018 was significantly different from that of POP2019 (t = − 4.35, p =0.00). Three moderate-effect (phenotypic variance [PVE] < 10.00%) GIC- and GZC-related QTL that were consistent between POP2018 and POP2019 were identified through inclusive composite interval mapping: qFe9, qFe11, and qZn7. All three QTL originated from the inferior parent Hwaseonchal. Epistasis analysis revealed that the GIC and GZC of POP2018 and POP2019 were affected by 79 significant digenic interactions with moderate and minor effects. By contrast, GZC was unaffected by digenic interactions. An interaction between loci on chromosomes 1 and 5 provided the highest contribution to the PVE (13.72%) for GIC. Candidate gene analysis revealed that 12 genes related to iron and zinc homeostasis or that require iron or zinc as ligands colocated with qFe9, qFe11, and qZn7. The QTL and epistatic regions identified here may be useful for developing rice varieties with high GIC and GZC in their milled grains. [ABSTRACT FROM AUTHOR]

Copyright of Yuzuncu Yil Universitesi Journal of Agricultural Sciences (YYU J Agr Sci) is the property of Yuzuncu Yil 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.)

Drought leads to serious yield losses and followed by increasing food prices. Thereby, drought tolerance is one of most important, pivotal issues for plant breeding and is determined by the very complex genetic architecture, which involves a lot of genes engaged in many cell processes. Within genomes of currently cultivated sugar beet forms, the number of favourable allelic variants is limited. However, there is a potential to identify genes related to drought tolerance deposited in genomes of wild or fodder relatives. Therefore, the goal of our study, was to identify the source of allelic variants involved in drought tolerance using a large spectrum of sugar or fodder beets and their wild relatives for analyses. Based on the drought tolerance index, calculated for morphophysiological traits, it was demonstrated that some of selected fodder beets showed the highest level of drought tolerance. The most drought tolerant fodder beet genotype did not show differences in the level of expression of genes engaged in osmoprotection and the antioxidative system, between control and drought condition, compared to sugar and wild beets. The genetic distance between selected beet forms was broad and ranged from 18 to 87%, however the most drought tolerant sugar, fodder and wild beets showed high genetic similarity and formed the common clade. Based on obtained results we propose that an adequate broad source of genes related to drought tolerance occurs in fodder beets, the crossing with which is easier, less time-consuming and more cost-effective than with wild forms of beets. • Some of fodder beets showed the higher drought tolerance than wild and sugar beets. • Genes engaged in osmoprotection and the antioxidant system are not involved in the response of fodder beet to drought. • The total genetic distance between Beta accessions was broad and ranged from 18 to 87%. • The most drought tolerant sugar, fodder and wild beets showed high genetic similarity and formed the common clade. • Appropriate source of genes related to drought tolerance for sugar beet might be fodder beet. [ABSTRACT FROM AUTHOR]