Euphytica最新文献

Enhancing nitrogen use efficiency (NUE) in crops, particularly under limited nitrogen availability, is pivotal for advancing sustainable agricultural practices. This study investigates the NUE and associated physiological responses in foxtail millets (Setaria spp.) subjected to varying nitrogen regimes. We selected two genotypes of S. viridis and four of S. italica, representing three distinct domestication stages. The study employed four nitrogen treatments: 0 mg/kg (N0), 25 mg/kg (N25), 50 mg/kg (N50), and 100 mg/kg (N100), ranging from nitrogen deficiency to sufficiency. Our findings highlight marked variances in phenotypic adaptations to nitrogen availability among these domestication stages. Notably, wild genotypes (Q4, Q23) performed well in lower nitrogen conditions, evidenced by substantial increases in shoot and root biomass. Conversely, cultivated genotypes (Yugu18, C28) flourished predominantly under higher nitrogen conditions, displaying significant growth in shoot and root biomass, alongside improvements in root length, surface area, and volume. A critical observation was that under nitrogen-limited conditions, wild genotypes exhibited superior NUE compared to their cultivated counterparts. Structural equation modeling (SEM) elucidated a positive correlation between NUE and root architecture in wild genotypes, contrasted by a negative association with plant nitrogen content. Our findings indicate that modern elite varieties do not perform as well as the wild species in adapting to poor soil conditions. Physiological responses to N fluctuation in foxtail millet is likely under selection during domestication and breeding processes.

The present study was conducted to find out high yield and good quality cucumber hybrids which can further be released for cultivation in the tropics under open filed conditions. Therefore, five lines (2 gynoecious, 1 each predominantly gynoecious, parthenocarpic gynoecious and predominantly gynoecious and parthenocarpic) and 11 testers (monoecious) were crossed in a line × tester mating design to develop 55 F₁ hybrids at Vegetable Research Farm, Punjab Agricultural University, Ludhiana. All the 71 genotypes were evaluated during spring–summer 2021 under open field conditions for 11 quantitative traits. Gene action study revealed the predominant role of non-additive genetic variance for all traits except for fruit length. On the basis of GCA (general combining ability) effect, lines PK-1, PBRK-11 and 25–46 VNR and testers Punjab Naveen, Pusa Uday and PMC-1were found to be best for fruit yield, quality and earliness which can be utilized as donor parents in future breeding. The maximum heterobeltiosis was recorded for fruit yield followed by fruit number per plant, fruit weight, fruit length and fruit diameter. The significant and positive correlation between GCA and mean of parental lines was observed for fruit yield, fruit number per plant, fruit length, and days to first fruit picking. Exploitation of the top performing hybrids ‘PK-1 × AVCU-1205, PK-1 × Swarna Ageti, PK-1 × PMC-1 and PBRK11 × Punjab Naveen’, after critical evaluation, could be recommended for commercial cucumber open field production in the tropics. Promising hybrids could also be exploited in segregating generations to identify pure lines having high yield with good fruit quality.

Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is a devastating fungal disease, leading to huge yield losses in wheat production. Identification of resistance genes and closely linked molecular markers can greatly facilitate breeding resistant wheat cultivars. Shaannong69 conferred high resistance to stripe rust both at the seedling and adult-plant stages. The Pst race CYR31 was used to infect Shaannong69, Huixianhong, F₁ and F₂ plants and F_2:3 lines at the seedling stage in the greenhouse. Genetic analysis identified a single dominant gene, designated as YrSN69, conferring resistance to Pst race CYR31 in Shaannong69. Seventy-four of 176 SNPs with the absolute value of ∆SNP-index more than 0.85 were identified in 753.33–766.18 Mb on chromosome 2BL based on bulked segregant RNA sequencing. Fifteen kompetitive allele-specific PCR markers were developed to genotype susceptible F₂ plants derived from the Shaannong69/Huixianhong cross. YrSN69 was mapped on chromosome arm 2BL in a 2.0 cM genetic interval, with genetic distances of 0.2 cM and 1.8 cM to markers 2BC17 and 2BA20, respectively, corresponding to a 3.16 Mb physical region based on the IWGSC RefSeq v1.1 with 44 high-confidence annotated genes. The YrSN69 is likely to be a new allele of Yr72 in comparison with known Yr genes on chromosome 2BL. These results provide a solid foundation for map-based cloning of YrSN69 and marker-assisted selection for pyramiding stripe rust resistance genes.

This study investigates the genetic contribution and decision-making coefficients of agronomic traits of upland cotton parents, and their F₁ crosses to provide a scientific basis for breeders to select and improve certain traits. Therefore, Genetic contribution and decision-making coefficients analysis were conducted on 4 agronomic traits and 4 yield traits of 130 upland cotton varieties (lines) and their 206 F₁ crosses using the additive-dominance genetic model and its interaction effect with the environment. The results showed that these traits had rich genetic diversity, and the coefficient of variation (CV) for these eight traits in the parents ranged from 4.68 to 50.83%, while that of the F₁ crosses was between 3.96 and 55.87%. The contribution rate of the additive effects of agronomic traits to yield, except for the first fruiting branch position and the lint percentage, was highly significant, ranging from 4 to 100%. Moreover, the additive contribution rate of the five petal boll rate and plant height to boll number and boll weight and the contribution rate of the dominance × environment interaction reached a positive and extremely significant level of more than 0.01. The additive variance, dominance × environment interaction, and residual variance among different models of genetic variation, as well as generalized heritability, significantly contributed to the total phenotypic variation in traits. The contribution of the dominance effect to the total phenotypic variation was highly significant, except for the boll number, and the contribution of the additive × environment interaction effect to the total phenotypic variation was highly significant, except for the lint yield. The main decision-making traits and limiting traits responsible for improving the yield of upland cotton hybrids were identified. The dominance decision-making coefficients of the lint yield, the decision-making coefficients of the dominance × environment interaction, the phenotypic decision-making coefficients, and the genotypic decision-making coefficients played a major role in determining the boll number. The decisive factors influencing boll weight, controlled by the additive effect, were the first fruiting branch position, plant height, and the five petal boll rate. The boll number was the most limiting trait affecting boll weight by influencing dominance decision-making coefficients, decision-making coefficients of the additive × environment interaction, decision-making coefficients of the dominance × environment interaction, phenotypic decision-making coefficients, and genotypic decision-making coefficients. Plant height and five petal boll number were the decision-making traits of lint percentage controlled by additive effects, while lint yield and boll weight were the major limiting traits.

The increase in the global human population and the accompanying challenges in meeting nutritional needs amidst climate change are a worldwide concern. Widespread protein and micronutrient deficiencies contribute to a significant number of individuals experiencing malnutrition, leading to severe health repercussions. This issue can be addressed through genomics-assisted breeding, particularly in enhancing the nutritional profile of vital staple crops like chickpea (Cicer arietinum L.). Chickpea, beyond being a rich source of protein, provides a diverse nutritional spectrum encompassing carbohydrates, fats, and minerals. To explore and improve the genetic basis of nutritional traits in chickpea, a study was conducted using 93 kabuli-type single plant derived lines and five cultivars in 2018, 2022, and 2023. Genotyping by sequencing revealed a total of 165K single nucleotide polymorphisms (SNPs) within this kabuli chickpea mini-core collection. After filtering for a minor allele frequency greater than 5%, 113,512 SNPs were utilized, distributed across eight chromosomes of the chickpea genome. Marker-trait associations were analyzed using genome wide association study, leading to the identification of 27 significantly associated SNPs from across all eight chromosomes linked to three seed nutritional concentrations and 100-seed weight. To unravel the molecular mechanisms governing seed protein, fiber, fat concentrations, and 100-seed weight, 31 candidate genes were determined within a 30 kb window size. This comprehensive approach holds promise for advancing crop breeding strategies to combat malnutrition and improve global food security.

Bacterial blight (BB) caused by Xanthomonas citri pv. malvacearum (Xcm), poses a significant threat to Upland cotton (Gossypium hirsutum L.) production worldwide, and Xcm race 18 is the most virulent and widespread and can cause serious yield loss. Understanding the genetic basis of resistance in diploid Asiatic cotton (G. arboreum) and successfully transferring the resistance to tetraploid Upland cotton are crucial for developing resistant cotton cultivars. This study aimed to identify chromosomal regions for BB resistance through a genome-wide association study (GWAS) using 245 G. arboreum accessions evaluated in two replicated greenhouse tests and to evaluate an introgression BC2F7 population derived from a tri-species hybrid (G. arboreum/G. aridum/G. hirsutum). In response to Xcm race 18 infections after artificial inoculation, 80% of the accessions exhibited a high level of resistance, including 151 accessions showing immunity with no visible foliar water-soaked lesions. A GWAS based on 7009 polymorphic SNP markers detected 9 major BB resistance QTLs on chromosomes A01, A02, A05, A06, A10, A12 and A13 in the Asiatic cotton. The tri-species introgression population showed segregation in BB resistance with significantly lower disease incidence of BB than the susceptible check Acala 1517-18 GLS (30.2 vs. 100%), suggesting that the resistance in the diploid species has been successfully transferred into Upland cotton. The identification of Xcm race 18 resistant diploid Asiatic cotton germplasm and specific chromosomal regions and candidate genes delineated by SNPs for resistance for the first time provides strong evidence that the Asiatic cotton is a new genetic source of resistance to Xcm race 18. The results will facilitate further genetic and genomic studies toward the eventual identification of resistance genes in Asiatic cotton and their transfer into tetraploid cotton through marker-assisted selection.

Identification of clones with promising growth and yield characteristics remains imperative for cocoa improvement in Ghana. This study assessed the relationship between selected trees from seed origin and their derived clones as a strategy to identify superior cocoa clones. Two experiments consisting of 40 progeny families, and 160 derived clones (plus 20 parents) respectively, were conducted at the Cocoa Research Institute of Ghana, New Tafo-Akim, from 2008 to 2022 to assess the genetic association between the two populations. Agronomic traits measured included stem diameter (vigour) at the juvenile and reproductive phases of growth, as well as bean yield and its components. Significant genetic variation was estimated among the ortets and their ramets for all measured traits. Relatively wide variation and superior performance were observed among the ramets compared with the ortets for all measured traits suggesting the achievement of substantial genetic improvement in the ramets to warrant selection progress. Additionally, the results revealed significant regression co-efficients and correlation patterns, along with high realized heritability values between the ortets and their ramets for bean yield and pod value indicating that high yielding clones with desirable pod values could be identified by relying on the genetic relationship between the progeny families and their derived clones. The high yielding ramets, CRG 0148/418, CRG 0121/106, CRG 0149/210, and CRG 0150/114 identified are therefore, invaluable for utilization in cocoa enhancement programmes across the globe.

There are thousands of Narcissus cultivars, however; their genome compositions are not so clear, except that their ploidy levels are extensively investigated. The present study analyzed eight popular cultivars using GISH or/and FISH. The present results clearly revealed their genome compositions: ‘Bridal Crown’ was diploid (2n = 2x = 17 = 10 + 7 = AE) rather than aneuploid, ‘Jinzhanyintai’ was autotriploid (2n = 3x = 30 = 10 + 10 + 10 = AAA) rather than allotetraploid or hexaploid, ‘Tête-à-Tête’ was allotriploid (2n = 3x = 24 + _B = 10 + 7 + 7 + _B = AEE), ‘Cultivar X’ was also allotriploid (2n = 3x = 24 = 10 + 7 + 7 = AEX), and ‘Dutch Master’, ‘Replete’ and ‘Queen’s Day’ were all autotetraploid (2n = 4x = 28 = 7 + 7 + 7 + 7 = EEEE). Together with other reports, we concluded that ‘Tête-à-Tête’ contained one genome of Narcissus tazetta, one genome of Narcissus cyclamineus, and one genome of Narcissus pseudonarcissus, and that ‘Pink Parasol’ was aneu-autotetraploid (2n = 4x + 2 = 30 = 7 + 7 + 7 + 7 + 2 = EEEE⁺²) rather allotetraploid (2n = 4x = 10 + 10 + 5 + 5 = CCDD). Based on the cultivar’s genome composition and origin, it is concluded that distant hybridization, sexual polyploidization and chromosome doubling play different roles in breeding modern Narcissus cultivars.

To address one of the main challenges restricting the development of global viticulture, it is imperative to breed high-quality and cold-resistant grape varieties. In this study, intraspecific cross-breeding was carried out between two cold resistance and four high-quality varieties for eight populations, including six reciprocal crosses and two crossing combinations. The cold-resistance of six hybrid parents and 481 hybrid F₁ progeny was determined by differential thermal analysis, and the cold-resistance grade and frequency distribution were analyzed from the 14 crossing combinations. Bioinformatics and statistical methods were used to mine and design SSR marker primers for 40 cold-resistance related genes. Agarose gel electrophoresis and cold-resistance measurement were used to screen molecular markers of the tested materials. The results showed that varying cold resistance for different populations, with a continuous distribution of cold resistance of intraspecific hybrid progenies of different crossing combinations. The screening and verification of molecular markers revealed that OMT2.1-211, SIRT276, UBC317-800, S238-854, and S241-717 can be used as standard markers to determine cold-resistance of intraspecific hybrid progenies of Ecolly or Meili and Marselan, and P5CS173, P5CS240, and SIRT276 could be used to rapidly screen intraspecific hybrid progenies of Ecolly or Meili and Cabernet Sauvignon. Intraspecific cross-breeding of V. vinifera can be applied to breed suitable intermediate materials or new cold-resistant materials. This work also provides a reference method for the development of SSR molecular markers to target specific genes of interest.

Flowering regulation is a reflection of plant self-adaptation to the environment and is the main determinant of plant yield. The quantitative trait loci (QTL) mapping of agronomic traits associated with the flowering stage of Agropyron Gaertn. was conducted using a cross-pollinated (CP) hybrid population with a total of 113 plant lines between A. mongolicum Keng Z2098 and A. cristatum (L.) Gaertn. Z1842 under four different environmental conditions and the genetic map constructed of 1,023 single-nucleotide polymorphism (SNP) markers. The results showed that 28 QTLs were detected on seven linkage groups. Each QTL explained 0.39–18.46% of the phenotypic variation, with a logarithm of odds (LOD) value ranging from 2.52 to 30.51. Specifically, QTLs were identified for various characteristics: one QTL identified for tiller number (TN), two for plant height (PH), three for days-to-flowering (DTF), five for flag leaf length (FLL), three for flag leaf width (FLW), three for spike length (SL), eight for spike width (SW), one for spikelet number per spike (SNS), and two for flower number per spike (FNS). One stable QTL controlling the SW was detected in two environments at the same loci and was located at 26 cM (Marker29867–Marker26864) on chromosome 5, showing a positive genetic effect. The two QTL enrichment regions suggested that the QTLs might contribute to trait correlation or pleiotropic genes. The identified QTLs potentially offer utility for marker-assisted breeding selection.