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This study included 22 rye inbred lines in S5 − 6 generations and one non-glaucous strain, originated from Bulgarian rye (Secale cereale L.) accession A9E1389. Variation in plant height, heading date, self- and open-fertility was recorded to characterize the inbred lines in two growing seasons. Plant height varied between 85 and 124 cm in the first year and between 93 and 131 cm in the second season. The lines headed in May, between 10th to 22nd with an average of May 15th. Fertility was calculated by dividing seeds to spikelet number in self- and open-pollinated spikes. Seed setting in self-fertility was lower than that of open-pollinated ears, but self-fertility in S5 was higher than the same trait in S6 generation (0.94 > 0.79 seeds per spikelet). Plant wax character was assessed and grouped as: glaucous phenotype, non-glaucous plant and non-glaucous spike. The non-glaucous inbred strain was studied over 3 years to show a stable expression of this trait. It was compared to its glaucous sister line, and to another glaucous inbred line, boring oblong shaped seeds. The waxless 389-9-2 was involved in crosses with four waxy lines in an open pollination scheme that produced hybrid seeds at a frequency of 36%. Analysis of F1 hybrids showed overdominance inheritance on the six studied traits in 83.3% of the hybrid plants. The results outlined the inbred lines used in crosses as promising genotypes for rye breeding. [ABSTRACT FROM AUTHOR]

Background: Plant senescence is the process of physiological maturation of plants and is important for crop yield and quality. Senescence is controlled by several factors, such as temperature and photoperiod. However, the molecular basis by which these genes promote senescence in soybeans is not well understood. We identified senescence-related genes via transcriptome analysis of early-senescence (ES)- and late-senescence (LS)-type plants to elucidate the molecular mechanisms of senescence in soybeans. Results: We obtained early-senescence (ES)- and late-senescence (LS)-type F7 plants from a cross between a hybrid (Glycine max × Glycine soja) and the Glycine max cultivar. The ES-type plants presented the reproductive (R2) growth stage at 50 days after sowing (DAS) and the R7 growth stage at 95 DAS, whereas the LS-type plants presented the beginning of the R1 and R6 growth stages at 50 and 95 DAS, respectively. To understand the molecular mechanisms underlying this senescence, we performed transcriptome analysis of leaves from 50 to 95 DAS of ES- and LS-type plants. A total of 2,414 and 2,471 genes at 50 and 95 DAS, respectively, were differentially expressed between ES-type and LS-type plants. Twenty-three candidate genes associated with the circadian clock, chlorophyll biosynthesis, phytohormones, and senescence-associated protein kinases were identified, and their expression levels were analyzed. In addition, to understand interaction between circadian clock and senescence, we analyzed expression patterns of seven circadian clock-related genes during the time period (light and dark condition): CIRCADIAN CLOCK ASSOCIATED 1 (CCA1), LATE ELONGATED HYPOCOTYL (LHY), CONSTANS-LIKE 9 (COL9), LUX ARRHYTHMO (LUX) EARLY FLOWERING 3 (ELF3), PSEUDO-RESPONSE REGULATOR5 (PRR5) and GIGANTEA (GI). The expression patterns of circadian clock-related genes were similar in the ES- and LS-type plants. However, the transcription levels of these genes were compared between ES- and LS-type plants, and the expression of these genes was greater than that in LS-type plants during the period when expression increased. Therefore, each set of candidate genes regulated senescence in each plant by regulating their expression level. Conclusions: These findings provide novel insights into the regulation of senescence in soybean plants, which could lead to the development of new strategies to improve agriculture. [ABSTRACT FROM AUTHOR]

Relevance. The technology of producing cabbage seeds with the traditional method takes almost 2 years. Its high labor intensity caused the need to search for cheaper methods of selection and seed production. One of the ways to speed up the stages of the selection process is the use of artificial climate chambers. The aim of research is to obtain seeds of promising inbred lines of late maturing white cabbage and hybrid combinations with their participation using rosette plants (steckling) in artificial climate chambers. Materials and Methods. The material was inbred pure lines of 5-6 generations of inbreeding, obtained from promising hybrid combinations of domestic and foreign breeding. The research was conducted in 2023-2024. Sowing in Plantek 64 cassettes was carried out on July 10, then the seedlings were transplanted into vegetative vessels with an optimal volume of 5-6 liters and installed in the open ground for the growth of a leaf outlet. In the phase 10-13 of real leaves, the plugs were placed in an artificial climate chamber. During the growth and development period, biometric and phenological observations were carried out, and an analysis of seed setting was carried out during the hybridization of inbred lines.Results. As a result of research in the study of hybrid seed production under artificial climate chamber conditions, high rates of seed setting in buds under cross-pollination of rosette plants of white cabbage were revealed. Genotypes with high seed set rate under geitenogamous bud pollination were also identified. The weight of 1000 seeds of the studied plants was within the range of 2.5-5.14 g. Genotypes 383-3, 384-2 and 384-7 were selected, which had the highest percentage of seeds in the fractional composition with size more than 2 mm 80.3%, 43.5% and 59.4%, respectively. When genotypes 384-2 and 384-7 were used in hybrid combinations as a maternal component, high quality indicators of the obtained seeds were revealed.Conclusion. For the studied genotypes of white cabbage, when grown in an artificial climate chamber, no significant effect on seed quality was found; the genotype had a greater effect on seed quality indicators.

Heat stress faced by the crop plants at seedling stage hinders its growth and if faced at reproductive stage affects crop production. Globally, maize (Zea mays L.) loses a substantial amount of its production due to very high temperatures at anthesis stage during spring season. So, development of heat tolerant maize cultivars is important for maize breeders. The ability of a plant to tolerate heat stress at seedling and reproductive stage is linked with each other and screening at the seedling stage could accelerate the selection process. In the present study, 50 maize inbred lines were screened for heat tolerance at seedling stage under in vitro conditions. Our results showed that parameters such as root length (RL), shoot length (SL), shoot fresh weight (SFW), shoot dry weight (SDW), root fresh weight (RFW), root dry weight (RDW), leaf area (LA), leaf fresh weight (LFW), leaf dry weight (LDW), relative water content (RWC), membrane stability index (MSI) and total chlorophyll (TCHL) showed a significant decrease under heat stress (p < 0.05). Further, morpho-physiological traits were delineated by principal component analysis (PCA). Hierarchical cluster analysis (HCA) was done with the objective to characterize the maize inbred lines based on their response under heat stress. Among the four column clusters, column cluster I showed highest mean values for maximum traits, i.e., RL (16.45 cm), RFW (0.27 g), SL (28.42 cm), SFW (0.74 g), SDW (63.03 mg), LFW (0.16 g), LDW (20 mg) and RWC (48.63%), suggesting that these traits were superior over other traits and inbred lines falling in this cluster would be selected directly on the basis of these traits. The heat tolerance index (HTI) of all the inbred lines based on individual traits was calculated and inbred lines were ranked accordingly. The top five inbred lines: LM22, CML579, LM13, LM16 and RIL 33 performed best under heat stress as they had high heat tolerance index value. The results obtained by PCA and HCA were in accordance with those obtained on the basis of HTI. Our study identified heat tolerant inbred lines of different heterotic pools which, after field validation, can be used for development of heat tolerant maize hybrids. [ABSTRACT FROM AUTHOR]

Following the identification of the self-compatibility gene (Sli) in diploid potatoes two decades ago, the breeding of inbred based diploid hybrid potatoes made its way. Tetraploid potatoes have a long history of cultivation through domestication and selection. Tetrasomic inheritance, heterozygosity and clonal propagation complicate genetic studies, resulting in a low genetic gain in potato breeding. Diploid hybrid TPS potato breeding, similar to the developments in hybrid maize, was pursued as an alternative to the genetic improvement of potatoes. However, several challenges, like self-incompatibility and high inbreeding depression associated with diploid potatoes, must be overcome to develop inbred lines in potatoes. Moreover, the inbred lines must retain good fertility and vigour for hybrid breeding. Good progress has been made by creating di-haploids of popular varieties, mapping self-incompatibility inhibitor gene, understanding the genetic basis of inbreeding depression, and identifying genomic regions for deleterious alleles and fertility. Further, the genome sequencing of diploid inbred lines has revealed the genetics of key traits associated with potato breeding. This article discussed these insights and summarized the progress of diploid hybrid TPS potato breeding. Recent advances in genetic and genomic research and genome editing technology have shown promise for this technology's success and far-reaching implications. [ABSTRACT FROM AUTHOR]

Triacylglycerides (TAGs) are neutral lipids and are one of the major energy storage forms in an insect aiding in normal physiology including reproduction of the organism. Importance of TAG metabolism in gametogenesis has been investigated in insects like mosquitoes, silkworm and Drosophila. However, a direct association between TAG levels and egg‐to‐adult viability has not been explored. In this study, we have assessed both stored and circulating TAG levels and egg‐to‐adult viability in Drosophila melanogaster lines with varying genetic backgrounds established through inbreeding and recombinant inbreeding strategies. We found noticeable variation in egg‐to‐adult viability and in both stored and circulating TAG levels in D. melanogaster lines. Apparently the D. melanogaster lines with higher levels of circulating TAG also had a higher egg‐to‐adult viability. To validate this, analysis of these variations through supervised correlation and unsupervised K‐means clustering showed that levels of circulating TAG are positively associated with egg‐to‐adult viability irrespective of gender. The findings suggest that levels of circulating TAG promotes successful transition of egg to an adult. Taken together, the findings not only have a potential application in husbandry of ecologically and economically important insects but also holds importance in translational research in fertility of vertebrates including humans. [ABSTRACT FROM AUTHOR]

Maize (Zea mays L.), a vital cereal crop, faces challenges from rising global temperatures. As a C4 plant, maize is highly heat sensitive, which disrupts photosynthesis and reduces growth and productivity. High temperatures during the reproductive phase delay silk emergence and dry pollen, decreasing seed production and yield. Developing heat-tolerant maize varieties is essential. Tolerance can be viable by utilizing genetic diversity in breeding programs. This study evaluated 156 inbred lines for high-temperature stress tolerance, selecting 56 promising lines. Their screening continued under field and screen house conditions. High-temperature stress significantly affected maize growth and reproductive stages, increasing the anthesis-silking interval and reducing flowering synchronization. Principal component analysis identified inbred lines PBG1(X), PBG2(X), PBG3(X), PBG4(X), PBG5(X), PBG7(X), 6200(X), 6201(X), 6205(X), and 6202(X) as the best performers under stress, while 6159(X), 6179(X), 6180(X), 6193(X), and 6199(X) performed poorly. Traits, such as cob diameter, days to silking, grains per cob, 100-grain weight, and leaf area, showed positive correlations with the anthesis-silking interval. Inversely, pollen production potential had a negative correlation, while the days to tasseling positively correlated with grain yield. These findings are crucial for developing heatresilient maize varieties. [ABSTRACT FROM AUTHOR]

The sunflower is a significant oil crop that can be cultivated in various environmental conditions. Due to the changing climate, the pathogen profile has been altered, posing a threat to sunflower production. Among the various threats, charcoal rot, caused by the soil-borne fungus Macrophomina phaseolina (Tassi) Goid, is one of the most significant pathogen. This study aimed to investigate the resistance of 80 sunflower inbred lines to this pathogen using two inoculation methods and naturally infested area under field conditions in two years, 2019 and 2020. The results showed that both inoculation methods and occurrence of disease in naturally infested area (DNI) effectively differentiated between resistant and susceptible inbred lines, with the toothpick method being the most effective. Thirteen inbred lines were resistant according to all inoculation methods, and the others were moderately resistant moderately susceptible or susceptible regarding to inoculation method. The study identified five inbred lines (Ha 74, L1, LIV 10, MA SC 2 and PB 21) as the most resistant, making them important sources for breeding sunflower hybrids resistant to M. phaseolina. Their resistance was confirmed in 2020, highlighting their potential to combat the impact of climate change on sunflower production. This study represents a valuable insight into the control of M. phaseolina using sunflower resistant genotypes, especially since resistance findings have been lacking in other plant species.

Drought is a major constraint for maize production in sub-Saharan Africa. Developing high-yielding drought-tolerant maize germplasm will safeguard maize yields in the ever-increasing fluctuating rainfall conditions. This study aimed to identify high-yielding inbred lines with stable performance for utilization in hybrid production. One hundred eighty-two (182) maize inbred lines were evaluated under well-watered and drought-stressed conditions at Ukulinga, Makhathini, and Cedara research stations in KwaZulu-Natal, South Africa. The experiments were carried out in a 13 × 14 alpha lattice design with two replications. The inbred lines exhibited significant differences (p ≤ 0.001) for grain yield and yield-related traits under well-watered and drought-stressed environments. The GGE biplot identified three mega-environments, clearly separating drought-stressed from well-watered environments. Inbred lines TZISTR1190, TZISTR1231, TZISTR1261 and CML540 were superior under well-watered conditions, while TZISTR1164 and CML390 performed well under drought condition. TZISTR1190 displayed both high average yield and stability across environments. Inbred lines combining stable high yielding performance in optimum and stress conditions such as TZISTR1190 and TZISTR1231, can be incorporated into local maize breeding pipelines to develop stable high yielding resilient hybrids. [ABSTRACT FROM AUTHOR]

Quinoa is emerging as a key seed crop for global food security due to its ability to grow in marginal environments and its excellent nutritional properties. Because quinoa is partially allogamous, we have developed quinoa inbred lines necessary for molecular genetic analysis. Our comprehensive genomic analysis showed that the quinoa inbred lines fall into three genetic subpopulations: northern highland, southern highland, and lowland. Lowland and highland quinoa are the same species, but have very different genotypes and phenotypes. Lowland quinoa has relatively small grains and a darker grain color, and is widely tested and grown around the world. In contrast, the white, large-grained highland quinoa is grown in the Andean highlands, including the regionwhere quinoa originated, and is exported worldwide as high-quality quinoa. Recently, we have shown that viral vectors can be used to regulate endogenous genes in quinoa, paving the way for functional genomics to reveal the diversity of quinoa. However, although a high-quality assembly has recently been reported for a lowland quinoa line, genomic resources of the quality required for functional genomics are not available for highland quinoa lines. Here we present high-quality chromosome-level genome assemblies for two highland inbred quinoa lines, J075 representing the northern highland line and J100 representing the southern highland line, using PacBio HiFi sequencing and dpMIG-seq. In addition, we demonstrate the importance of verifying and correcting reference-based scaffold assembly with other approaches such as linkage maps. The assembled genome sizes of J075 and J100 are 1.29 and 1.32 Gb,with contigs N50 of 66.3 and 12.6Mb, andscaffoldN50of 71.2 and70.6Mb, respectively, comprising 18 pseudochromosomes. The repetitive sequences of J075 and J100 represent 72.6% and 71.5% of the genome, the majority of which are long terminal repeats, representing 44.0% and 42.7% of the genome, respectively. The de novo assembled genomes of J075 and J100 were predicted to contain 65,303 and 64,945 protein-coding genes, respectively. The high quality genomes of these highland quinoa lines will facilitate quinoa functional genomics research on quinoa and contribute to the identification of key genes involved in environmental adaptation and quinoa domestication. [ABSTRACT FROM AUTHOR]

Water deficit stress reduces crop yield in field crops, including sunflowers, at any growth stage. In response, most plants activate hormonal and gene expression patterns to mitigate damage. In this study, we evaluated changes in the physiological and gene transcription levels of two sunflower (Helianthus annuus L.) inbred lines -one sensitive (B59 line) and one water stress-tolerant (B71)–in response to water stress, by using mannitol to simulate water deficit conditions, which provides moderate stress in both sunflower lines. The analyses of the accumulation of various phytohormones under this stress revealed that Jasmonic acid (JA) significantly increased in the shoots of both lines. Similarly, Salicylic acid (SA) increased in the shoots of both lines, although it also accumulated in B71 roots. In addition, Abscisic acid (ABA) and Indole-3-acetic acid (IAA) showed a considerable increase in the B59 shoots. Regarding the JA and SA pathways, the WRKY70 transcription levels were higher in the shoots of both lines and the roots of B71. The B59 line showed overtranscription of a gene related to the ABA pathway (XERICO) and genes associated with IAA (ARF9 and ARF16 genes). The B71 line, on the other hand, simultaneously triggered the JA, SA and ABA hormonal pathways in response to this stress condition. The ABA and JA hormonal pathways activated different TFs, such as RD20, RD22, RD26, ANAC19 and ANAC29, through MYC2. Both the JA and SA hormonal pathways activated the WRKY70 transcription factor. Altogether, each line triggered the hormonal and transcriptional pathways in response to water stress, although at varying intensities. The results suggest that the hormonal pathways of JA, SA, IAA and ABA, along with their primary associated genes, are activated in response to water deficit at the early growth stage in sunflower seedlings, which mitigates damage. [ABSTRACT FROM AUTHOR]

The sunflower is a significant oil crop that can be cultivated in various environmental conditions. Due to the changing climate, the pathogen profile has been altered, posing a threat to sunflower production. Among the various threats, charcoal rot, caused by the soil-borne fungus Macrophomina phaseolina (Tassi) Goid, is one of the most significant pathogen. This study aimed to investigate the resistance of 80 sunflower inbred lines to this pathogen using two inoculation methods and naturally infested area under field conditions in two years, 2019 and 2020. The results showed that both inoculation methods and occurrence of disease in naturally infested area (DNI) effectively differentiated between resistant and susceptible inbred lines, with the toothpick method being the most effective. Thirteen inbred lines were resistant according to all inoculation methods, and the others were moderately resistant moderately susceptible or susceptible regarding to inoculation method. The study identified five inbred lines (Ha 74, L1, LIV 10, MA SC 2 and PB 21) as the most resistant, making them important sources for breeding sunflower hybrids resistant to M. phaseolina. Their resistance was confirmed in 2020, highlighting their potential to combat the impact of climate change on sunflower production. This study represents a valuable insight into the control of M. phaseolina using sunflower resistant genotypes, especially since resistance findings have been lacking in other plant species. [ABSTRACT FROM AUTHOR]

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Abstract Background Flight can drastically enhance dispersal capacity and is a key trait defining the potential of exotic insect species to spread and invade new habitats. The phytophagous European spongy moths (ESM, Lymantria dispar dispar) and Asian spongy moths (ASM; a multi–species group represented here by L. d. asiatica and L. d. japonica), are globally invasive species that vary in adult female flight capability—female ASM are typically flight capable, whereas female ESM are typically flightless. Genetic markers of flight capability would supply a powerful tool for flight profiling of these species at any intercepted life stage. To assess the functional complexity of spongy moth flight and to identify potential markers of flight capability, we used multiple genetic approaches aimed at capturing complementary signals of putative flight–relevant genetic divergence between ESM and ASM: reduced representation genome–wide association studies, whole genome sequence comparisons, and developmental transcriptomics. We then judged the candidacy of flight–associated genes through functional analyses aimed at addressing the proximate demands of flight and salient features of the ecological context of spongy moth flight evolution. Results Candidate gene sets were typically non–overlapping across different genetic approaches, with only nine gene annotations shared between any pair of approaches. We detected an array of flight–relevant functional themes across gene sets that collectively suggest divergence in flight capability between European and Asian spongy moth lineages has coincided with evolutionary differentiation in multiple aspects of flight development, execution, and surrounding life history. Overall, our results indicate that spongy moth flight evolution has shaped or been influenced by a large and functionally broad network of traits. Conclusions Our study identified a suite of flight–associated genes in spongy moths suited to exploration of the genetic architecture and evolution of flight, or validation for flight profiling purposes. This work illustrates how complementary genetic approaches combined with phenotypically targeted functional analyses can help to characterize genetically complex traits.

Abstract Background Using a desirable tester is considered one method used to maximise genetic differences among test crosses derived from new inbred lines and improves the overall performance of maize. Thus, this study aimed to evaluate the potency of the tester with varying levels of resistance to Striga hermonthica in determining the testcross performance of the hybrids for Striga resistance and yield-related traits. Method The experiment was conducted with these test crosses and two standard checks (susceptible and tolerant) for different Striga resistance and agronomic traits during the 2018 cropping season in Abuja and Mokwa, Nigeria. The experiment was laid out in a 23 × 4 alpha-lattice design with two replications in each location. Field evaluation data was collected from Striga resistance and yield-related traits to estimate the performance of test crosses. Analysis of variance was conducted to determine the variance of the testcross performance. Results There were significant differences among test crosses for days to silking, days to pollen shedding, ear at harvest, ear aspect, ear per plant, grain yield, Striga damage rating at 8 and 10 weeks after planting (WAP), and Striga count at 8 and 10 WAP. Variations among test crosses were always higher than the corresponding variations due to the interaction between test crosses and the environment for all traits. Conclusion The inbred lines with low yield reduction crossed with different testers under Striga infested were recorded. These inbreds should be used to develop high-yielding hybrids and synthetics with elevated levels of Striga resistance to improve the maize breeding program.

Spontaneous tumour formation in higher plants can occur in the absence of pathogen invasion, depending on the plant genotype. Spontaneous tumour formation on the taproots is consistently observed in certain inbred lines of radish (Raphanus sativus var. radicula Pers.). In this paper, using Oxford Nanopore and Illumina technologies, we have sequenced the genomes of two closely related radish inbred lines that differ in their ability to spontaneously form tumours. We identified a large number of single nucleotide variants (amino acid substitutions, insertions or deletions, SNVs) that are likely to be associated with the spontaneous tumour formation. Among the genes involved in the trait, we have identified those that regulate the cell cycle, meristem activity, gene expression, and metabolism and signalling of phytohormones. After identifying the SNVs, we performed Sanger sequencing of amplicons corresponding to SNV-containing regions to validate our results. We then checked for the presence of SNVs in other tumour lines of the radish genetic collection and found the ERF118 gene, which had the SNVs in the majority of tumour lines. Furthermore, we performed the identification of the CLAVATA3/ESR (CLE) and WUSCHEL (WOX) genes and, as a result, identified two unique radish CLE genes which probably encode proteins with multiple CLE domains. The results obtained provide a basis for investigating the mechanisms of plant tumour formation and also for future genetic and genomic studies of radish. [ABSTRACT FROM AUTHOR]

Sexual dimorphism in traits of insects during the developmental stages could potentially be the direct or indirect result of sex-specific selection provided that genetic variation for sexual dimorphism is present. We investigated genetic variation in sexual dimorphism in a set of Drosophila melanogaster inbred lines for 2 traits: egg to adult development time and pupation site preference. We observed considerable genetic variation in sexual dimorphism among lines in both traits. The sexual dimorphic patterns remained relatively consistent across multiple trials, despite both traits being sensitive to environmental conditions. Additionally, we measured 2 sexually dimorphic adult morphological traits in 6 sampled lines and investigated correlations in the sexual dimorphism patterns with the 2 developmental traits. The abundance of genetic variation in sexual dimorphism for D. melanogaster developmental traits demonstrated in this study provides evidence for a high degree of evolvability of sex differences in preadult traits in natural populations. [ABSTRACT FROM AUTHOR]

Watermelon mosaic virus (WMV) is one of the most important viruses of cucurbit plants. In this research, the reaction of 10 cantaloupe and eight watermelon Ajili (Jabani) inbred lines was evaluated under greenhouse conditions against a WMV isolate. Results indicated that only the inbred line of cantaloupe selfing 2 showed a delay in symptoms development which attributed to low disease severity index and average absorbance in ELISA test. Therefore, it was considered as resistant inbred line to the virus. While the inbred lines 3, 5, 6 and 8 were moderately susceptible and 4, 7, 10 and 11 were susceptible to the virus. Among watermelon inbred lines, 2 and 5 were found to be susceptible, whereas other accessions did not show any disease symptoms and also their severity index were recorded to be zero. Furthermore, results of enzyme-linked immunosorbent assay (ELISA) and RT-PCR tests showed that the later accessions are resistant to WMV. To assess the virus's impact on plant biomass, cantaloupe and watermelon inbred lines were mechanically inoculated with the WMV. Results indicated that the susceptible cantaloupes and watermelons against WMV were found to have significantly lower fresh leaves, dry stems and biomass than control plants (non-inoculated). Collectively, the cantaloupe inbred lines 1 and 2 and watermelon inbred lines 1, 3, 6, 7, 8 and 11 used in this study are probably resistant against WMV and can be recommended in breeding programs to establish more resistant crops. [ABSTRACT FROM AUTHOR]

Foliar fertilization is a cropping practice measure that, in addition to basic fertilization, which provides plants with macroelements, can supply the cultivated crop with microelements, phytohormones, and amino acids. This research aimed to examine the influence of foliar fertilizers on the morphological characteristics (fresh above-ground mass, leaf area index, and height) and grain yield of five Maize Research Institute "Zemun Polje" maize inbred lines, during the period 2019-2021. Foliar fertilizers were applied in different stages of maize: Đ1 - fertilizer with increased nitrogen content and amino acids was applied when the maize was in the stage of 5-6 developed leaves. The second tested fertilizer with an increased phosphorus content, Đ2, was applied a bit later, at the stage of 11-12 leaves. The experiment also included a control variant on which no foliar fertilizers were applied. Based on the obtained results, fertilizer Đ1 proved to be better compared to Đ2, which indicates the possibility of applying this fertilizer in order to increase plant height, fresh above-ground mass and grain yield.

Abstract RNA silencing plays an important role in plant antiviral responses, which trigger the production of virus-derived small interfering RNAs (vsiRNAs). The competing endogenous RNA (ceRNA) hypothesis revealed a unique mechanism in which circular RNAs (circRNAs) and long non-coding RNAs (lncRNAs) can interact with small RNAs to regulate the expression of corresponding target mRNAs. Sugarcane mosaic virus (SCMV) infection causes severe economic losses in maize (Zea mays L.) production worldwide. This study compared and analyzed characteristics of vsiRNAs derived from SCMV and their target genes in resistant (Chang7-2) and susceptible (Mo17) maize inbred lines through whole-transcriptome RNA sequencing and degradome sequencing. The results showed that 706 transcripts were targeted by 204 vsiRNAs, including 784 vsiRNA-target gene pairs. Furthermore, ceRNA networks of circRNA/lncRNA-vsiRNA-mRNA in response of maize to SCMV infection were obtained, including 3 differentially expressed (DE) circRNAs, 36 DElncRNAs, 105 vsiRNAs, and 342 DEmRNAs in Mo17 plants, and 3 DEcircRNAs, 35 DElncRNAs, 23 vsiRNAs, and 87 DEmRNAs in Chang7-2 plants. Our results also showed that the transcripts of ZmDCLs, ZmAGOs, and ZmRDRs were differentially accumulated in resistant and susceptible maize inbred lines after SCMV infection. These findings provide valuable insights into the relationship between SCMV-derived vsiRNAs and potential ceRNAs fine-tuning the SCMV-maize interaction and offer novel clues to reveal the mechanism underlying the pathogenesis of SCMV.

Salinity stress is a major abiotic stress to which rice is most sensitive at germination or early vegetative stages. Addressing a salinity tolerance in rice can be achieved with an effective way by employing of early seedling stage screening to narrow down a large set of germplasm with higher tolerance and key parameters can quantify tolerance level. Morpho-physiological changes were assessed for selected seven backcross inbred lines (BILs) possessing Saltol1 quantitative trait loci (QTL) of rice and their parents and checks, at early seedling stage under optimal salt concentration (120 mM NaCl). In the present study, morpho-physiological changes were assessed for selected seven backcross inbred lines (BILs) possessing Saltol1 QTL of rice and their parents and checks, at seedling stage subjected to 120 mM NaCl salt concentration. The seedling growth assessment, mineral analysis and important physiological growth characters were measured after 14 days of salt treatment to classify seven BILs into tolerant and sensitive groups. Among the screened seven ILs, IL3 showed susceptible reaction for hydroponic screening. Analysis of variance (ANOVA) revealed significant variation between improved lines, salinity treatment and their interaction for the studied traits. Salt stress affected growth parameters and important physiological traits in the studied ILs; however, the lowest reduction was observed in the tolerant groups. The tolerant group ILs also showed maintenance of low Na+, high K+ uptake and Na+/K+ ratio. The identified tolerant lines will be utilized in development of saline-tolerant heterotic hybrids and further evaluation under multi-location trial of All India Coordinated Rice Improvement Programme (AICRIP). [ABSTRACT FROM AUTHOR]

RNA silencing plays an important role in plant antiviral responses, which trigger the production of virus-derived small interfering RNAs (vsiRNAs). The competing endogenous RNA (ceRNA) hypothesis revealed a unique mechanism in which circular RNAs (circRNAs) and long non-coding RNAs (lncRNAs) can interact with small RNAs to regulate the expression of corresponding target mRNAs. Sugarcane mosaic virus (SCMV) infection causes severe economic losses in maize (Zea mays L.) production worldwide. This study compared and analyzed characteristics of vsiRNAs derived from SCMV and their target genes in resistant (Chang7-2) and susceptible (Mo17) maize inbred lines through whole-transcriptome RNA sequencing and degradome sequencing. The results showed that 706 transcripts were targeted by 204 vsiRNAs, including 784 vsiRNA-target gene pairs. Furthermore, ceRNA networks of circRNA/lncRNA-vsiRNA-mRNA in response of maize to SCMV infection were obtained, including 3 differentially expressed (DE) circRNAs, 36 DElncRNAs, 105 vsiRNAs, and 342 DEmRNAs in Mo17 plants, and 3 DEcircRNAs, 35 DElncRNAs, 23 vsiRNAs, and 87 DEmRNAs in Chang7-2 plants. Our results also showed that the transcripts of ZmDCLs, ZmAGOs, and ZmRDRs were differentially accumulated in resistant and susceptible maize inbred lines after SCMV infection. These findings provide valuable insights into the relationship between SCMV-derived vsiRNAs and potential ceRNAs fine-tuning the SCMV-maize interaction and offer novel clues to reveal the mechanism underlying the pathogenesis of SCMV. [ABSTRACT FROM AUTHOR]

Spring black stem and leaf spot, caused by Phoma medicaginis, is an issue in annual Medicago species. Therefore, in this study, we analyzed the response to P. medicaginis infection in a collection of 46 lines of three annual Medicago species (M. truncatula, M. ciliaris, and M. polymorpha) showing different geographic distribution in Tunisia. The reaction in the host to the disease is explained by the effects based on plant species, lines nested within species, treatment, the interaction of species × treatment, and the interaction of lines nested within species × treatment. Medicago ciliaris was the least affected for aerial growth under infection. Furthermore, the largest variation within species was found for M. truncatula under both conditions. Principal component analysis and hierarchical classification showed that M. ciliaris lines formed a separate group under control treatment and P. medicaginis infection and they are the most vigorous in growth. These results indicate that M. ciliaris is the least susceptible in response to P. medicaginis infection among the three Medicago species investigated here, which can be used as a good candidate in crop rotation to reduce disease pressure in the field and as a source of P. medicaginis resistance for the improvement of forage legumes.

The aim of this study was to assess the chemical composition and bioactive properties of the wholegrain flour obtained from eleven maize inbred lines to identify genotypes with increased potential for the development of hybrids with high nutritional and functional value, suitable for food production. The maize inbreds, including seven standard yellow, two QPM (quality protein maize) and two lines for red kernel hybrids, were grown in the experimental field of the Maize Research Institute at the location of Zemun Polje, Serbia. Wholegrain maize flour was got by grinding the maize grain in a laboratory mill. The assessment of the chemical composition and content of certain bioactive compounds, as well as the total antioxidant capacity, was conducted using standard laboratory procedures. The highest starch content (73.73%) was determined in line L8, while line L10 had the highest protein content (12.82%). Among soluble proteins, the a-zein fraction was dominant in most of the lines, ranging from 0.92% to 3.57%. The highest content of total fibres (NDF) was determined in red kernel line L9 (15.77%). Line L8 was the richest in total carotenoids (21.08 mg bCE/g d.m.), while line L7 had the highest total antioxidant capacity (34.30 mmol Trolox/kg d.m.), which can be explained by the presence of anthocyanins in the red grain. Line L1 had the highest content of total sugars (3.36%), and line L4 had the lowest (1.44%). Most of the samples of inbred lines investigated in this study showed good quality parameters regarding chemical composition and bioactive properties. The obtained results may provide some valuable guidelines needed in the following stages of maize breeding and open up various possibilities for the utilization of wholegrain maize flour in the food industry.

AbstractBreeding for nutrient-dense maize cultivars is reliant on introductions of exotic inbred lines enhanced with high levels of the targeted nutrients. Sometimes, the exotic nutrient donor germplasm may not adapt well in new growing environments, thereby reducing seed production when used in hybrid combinations. Therefore, evaluating introduced trait donors for adaptation, through genotype × environment interaction (GEI) analysis is crucial in breeding for quality traits. The objectives of this study were to (i) evaluate grain yield performance of introduced zinc-enhanced, provitamin A, normal and quality protein maize lines across stress and non-stress environments in Zimbabwe, (ii) assess the presence of GEI and (iii) identify high yielding and stable lines that could be used for developing Zn-enhanced hybrids with improved seed producibility. Additive main effects and multiplicative interaction (AMMI) and genotype plus genotype × environment interaction (GGE) biplot analyses were used for stability analysis. GEI effects were highly significant (P ≤ 0.01) for grain yield. Grain yields for the inbred lines ranged from 1.28 to 3.5 t ha−1. The Zn donor G11 (ITZN313) had the highest grain yield of 3.5 t ha−1 across environments, whereas the normal check G24 (CZL1111) had the lowest grain yield. G2 (CLWQHZN14), G4 (CLWQHZN19), G8 (OBATANPA6), G11 (ITZN313) and G18 (CML546) were stable and high yielding and can be used for developing Zn-enhanced hybrids. Five mega-environments were identified, clearly separating stress and non-stress environments. E11 (Chisumbanje WW) was the most discriminating and representative test environment and could be used to identify superior genotypes.

Bipolaris is one of the most important phytopathogenic fungal genera to cause disease in cereal crops. Southern corn leaf blight (SCLB) is a pandemic and widespread disease; it's found everywhere corn is grown, causing a noticeable reduction in crop yield. Most cultivated varieties of maize do not resist SCLB disease where it is reported. Nevertheless, previous researchers have reported some resistant varieties of maize. In this study, we tested inbred and hybrid lines collected from ICAR‐IIMR based in Ludhiana against the disease. The field experiment was setup using a Randomized Block Design with three replications in natural conditions. Here we evaluated lines by quantifying disease pressure, yield, and their attributes. Moreover, model‐based clustering allowed the identification of five groups. For the SCLB disease confirmation, infected maize leaves were collected and used for pathogen isolation, and a pure culture was maintained. Both disease assessment and data analysis focused more specifically on characters that showed significant differences between means, especially leaf area, percentage of leaf infection, disease incidence, disease severity, disease index by plot basis, number of grain rows formed per ear, weight of maize kernels per ear, each corn ear weight, shelling percentage, and grain yield. The two best clusters identified, namely Group 1 and Group 2, together comprise 11002, 11009, 11026, 11030, 11069, 11149, 11153, 11185, 11328, 11333, 11337, 11347, 11370, 11385, 11074, 11351, 11356, 11357, 11608, and Karav‐8523 lines. As per disease reaction, CM‐500 is individually one of the best lines in terms of SCLB resistance. Specific symptoms were clearly found on leaves, and pseudo‐septate conidia were observed under the microscope. Thus, several lines exhibited highly resistant reactions against SCLB, especially 11002, 11009, 11026, 11069, 11074, 11337, 11347, 11385, and CM‐500, and can still be recommended for farmers and in breeding programmes, for future usefulness as industries are complaining of maize shortages, and they present a great commercial potential. [ABSTRACT FROM AUTHOR]

The low yield potential of most biofortified maize is a barrier to its full adoption and reduces its potential to curb various macro‐ and micronutrient deficiencies highly prevalent in low‐income regions of the world, such as sub‐Saharan Africa (SSA). By crossing biofortified inbred lines with different nutritional attributes such as zinc (Zn), provitamin A and protein quality, breeders are attempting to develop agronomically superior and stable multi‐nutrient maize of different genetic backgrounds. A key question, however, is the relationship between the biofortified inbred lines per se and hybrid performance under stress and non‐stress conditions. In this study, inbred line per se and testcross performance were evaluated for grain yield and secondary traits of Zn‐enhanced normal, provitamin A and quality protein maize (QPM) hybrids and estimated heterosis under combined heat and drought (HMDS) and well‐watered (WW) conditions. Responses of all secondary traits, except for the number of days to mid‐anthesis, significantly differed for HMDS and WW conditions. The contribution of heterosis to grain yield was highly significant under both management levels, although higher mid and high‐parent heterosis was observed under WW than HMDS conditions. However, the findings suggest that inbred line performance was the best determinant of hybrid performance under HMDS. Strong correlations were observed between grain yield and secondary traits for both parents and hybrids, and between secondary traits of inbred lines and hybrids under both management levels, indicating that hybrid performance can be predicted based on intrinsic inbred line performance. Phenotypic correlation between grain yield of inbred lines and hybrids was higher under HMDS than WW conditions. This study demonstrated that under HMDS conditions, performance of Zn‐enhanced hybrids could be predicted based on the performance of their corresponding inbred lines. However, the parental inbred lines should be systematically selected for desirable secondary traits correlated with HMDS tolerance during inbred line development. [ABSTRACT FROM AUTHOR]

Improving the quality of the grains allows both diversification and increasing the economic value of the maize crop. Knowing the determinism of grain quality is important in association with the improvement of yield, but also for the improvement of some nutritional and industrial properties. The biological material used in the study is represented by simple hybrids resulted within a system of cyclic (factorial) crossings of the m x n type, meaning 7 inbred lines were crossed with 3 tester inbred lines. 3 control hybrids were added, resulting in 24 variants -- 3 repetitions x 2 rows/plot, in three experimental years: 2016, 2017 and 2018. The biochemical content of the hybrids was determined using the Tango NIR chemical analyzer. Protein, fat, starch, fiber, NCGD, NDF and ADF were analyzed. In all three experimental years, statistically significant differences were noted for the studied quality indices, being influenced both by the factor year, genotype and by the interaction between the two. [ABSTRACT FROM AUTHOR]

Maize inbred lines derived from local populations (Cycle I lines) were tested using cycle II elite inbred lines. In the crossing system, the hybrids have a large variability for yield (6,601-10,571 kg/ha), the largest differences between hybrids are due to the non-additive genetic effects; undesirable traits transmitted by cycle I inbred lines are weak resistance to stalk breaking and fallen plants; for the percentage of unbroken plants, the genetic variability is high, the percentage of unbroken plants for simple hybrids has a range value between 65.02% and 89.70%. Correlation coefficients were calculated between the "per se" values of the inbred lines in the cross system and the values of additive genetic effects calculated in the "m x n" cross system. Positive correlations were identified between "per se" values and positive genetic effects for yield, ear weight, ear length, number of grains per ear, TKW, grain depth. These high positive correlation values indicate the possibility of using phenotypic markers in the process of creating inbred lines. [ABSTRACT FROM AUTHOR]

Knowledge of relatedness among maize elite breeding genotypes is useful in planning crosses for hybrid and inbred line improvement and assigning them into heterotic groups. This study investigated phenotypic and genetic similarities or diversities between 7 flint inbred lines (of common origin) adapted to the early maize growing regions created at ARDS Turda-Romania. They were studied for per se traits and in two crossing systems: a diallel crossing system, resulting in 21 hybrids and a cyclic system using four testers, thus resulting in 28 maize hybrids. Both parental inbred lines and hybrids were evaluated for several traits over three years. The level of relatedness/diversity was determined by various methods, grouped into: phenotypic methods and genetic methods. Similarities were identified between certain lines and a degree of differentiation between others. The analysis of the hybrid combinations from the diallel crossings between the seven sister lines highlighted the TD236 inbred line as the only one that differs genetically from the other. Following the analysis of the data obtained in the cyclic system, some inbred lines can be sources of favorable traits: TD236 and TD233 for yield, ear weight, grain/ear weight; TD233 and TD234 for the number of kernels/row, TD237 for plant breaking resistance. [ABSTRACT FROM AUTHOR]

Maize is one of the most important crops, both worldwide and in Romania, and preserving the diversity of the biological material used in the breeding of this plant is of particular importance. The Agricultural Research and Development Station (ARDS) Turda, Romania, inbred lines collection includes both its own genotypes and some obtained as a result of germplasm exchanges with other institutions in the country or abroad. In the present study, 575 lines created at Turda were analysed regarding some traits of the plant (plant height, ear height, total number of leaves, number of tassel branches) and the ear (ear length and weight, number of kernel rows and number of kernels/row). The biological material used in this study shows a great diversity: a medium or high variability coefficient was identified for several of the traits analysed (number of tassel branches, ear height, ear height). Frequency histograms were made for the studied lines, for plant and ear traits. A great variability also was observed in the colours of the anther and silk, but also for kernel type and colour and cob colour. [ABSTRACT FROM AUTHOR]

As plant breeding is a very complex and sophisticated process, it is of paramount importance to understand the nature and magnitude of interdependence between specific plant features. Using PCA and correlation analysis, this study examined the variability in features of two types of inbred sunflower lines and determined its connection with their seed yields. The experiment was conducted as a randomized complete block design with four replications in Rimski Šančevi (the experimental field of the Institute of Field and Vegetable Crops in Novi Sad) in 2018 and 2019. It examined a total of nine inbred sunflower lines created at the Institute of Field and Vegetable Crops in Novi Sad. The results obtained suggest a high degree of variability in the examined traits of inbred sunflower lines considered, whereas the significance indicated by the F test was confirmed by the Duncan test performed. A high degree of variability was also found between the different types of inbred lines considered. A positive correlation was found between all four traits observed in the inbred sunflower lines considered, with different levels of significance. A statistically significant positive increase in the head diameter was followed by an increase in the weight of 1000 seeds, which generated a higher seed yield per unit area. According to the arrangement of different types of inbred lines considered on the PCA biplot, it can be concluded that the linoleic inbred lines G7L and G8L had the highest average values of the 1000-seed weight, head diameter and seed yield throughout the course of both experimental years. The useful data obtained by PCA analysis can facilitate successful selection programs aimed at developing sunflower genotypes that possess high stability and seed yields.

Domestication and genetic improvement of maize improve yield and stress tolerance due to changes in morphological and physiological properties, which likely alter rhizosphere microbial diversity. Understanding how the evolution of maize germplasm impacts its rhizobacterial traits during the growth stage is important for optimizing plant-microbe associations and obtaining yield gain in domesticated germplasms. In this study, a total of nine accessions representing domestication and subsequent genetic improvement were selected. We then sequenced the plant DNA and rhizobacterial DNA of teosinte, landraces and inbred lines at the seedling, flowering and maturity stages in a field trial. Moreover, the soil chemical properties were determined at the respective stages to explore the associations of soil characteristics with bacterial community structures. The results showed that domestication and genetic improvement increased the rhizobacterial diversity and substantially altered the rhizobacterial community composition. The core microbiome in the rhizosphere differed among germplasm groups. The co-occurrence network analysis demonstrated that the modularity in the bacterial network of the inbred lines was greater than those of teosinte and the landraces. In conclusion, the increased diversity of the rhizobacterial community with domestication and genetic improvement may improve maize resilience to biotic stresses and soil nutrient availability to plants.

Many parasites can interfere with their host's defences to maximize their fitness. Here, we investigated if there is heritable variation in the spider mite Tetranychus evansi for traits associated with how they interact with their host plant. We also determined if this variation correlates with mite fecundity. Tetranychus evansi can interfere with jasmonate (JA) defences which are the main determinant of anti-herbivore immunity in plants. We investigated (i) variation in fecundity in the presence and absence of JA defences, making use of a wild-type tomato cultivar and a JA-deficient mutant (defenseless-1), and (ii) variation in the induction of JA defences, in four T. evansi field populations and 59 inbred lines created from an outbred population originating from controlled crosses of the four field populations. We observed a strong positive genetic correlation between fecundity in the presence (on wild-type) and the absence of JA defences (on defenseless-1). However, fecundity did not correlate with the magnitude of induced JA defences in wild-type plants. Our results suggest that the performance of the specialist T. evansi is not related to their ability to manipulate plant defences, either because all lines can adequately reduce levels of defences, or because they are resistant to them.

Chicory, a horticultural crop cultivated worldwide, presents many botanical varieties and local biotypes. Among these, cultivars of the Italian radicchio group of the pure species Cichorium intybus L. and its interspecific hybrids with Cichorium endivia L.—as the "Red of Chioggia" biotype—includes several phenotypes. This study uses a pipeline to address the marker-assisted breeding of F1 hybrids: it presents the genotyping-by-sequencing results of four elite inbred lines using a RADseq approach and an original molecular assay based on CAPS markers for screening mutants with nuclear male sterility in the radicchio of Chioggia. A total of 2953 SNP-carrying RADtags were identified and used to compute the actual estimates of homozygosity and overall genetic similarity and uniformity of the populations, as well as to determine their genetic distinctiveness and differentiation. Molecular data were further used to investigate the genomic distribution of the RADtags among the two Cichorium species, allowing their mapping in 1131 and 1071 coding sequences in chicory and endive, respectively. Paralleling this, an assay to screen the genotype at the male sterility locus Cims-1 was developed to discriminate wild-type and mutant alleles of the causative gene myb80-like. Moreover, a RADtag mapped close to this genomic region proved the potential application of this method for future marker-assisted selection tools. Finally, after combining the genotype information of the core collection, the best 10 individuals from each inbred line were selected to compute the observed genetic similarity as a measure of uniformity as well as the expected homozygosity and heterozygosity estimates scorable by the putative progenies derived from selfing (pollen parent) and full-sibling (seed parent) or pair-wise crossing (F1 hybrids). This predictive approach was conducted as a pilot study to understand the potential application of RADseq in the fine tuning of molecular marker-assisted breeding strategies aimed at the development of inbred lines and F1 hybrids in leaf chicory. [ABSTRACT FROM AUTHOR]

Virulence is expected to be linked to parasite fitness via transmission. However, it is not clear whether this relationship is genetically determined, nor if it differs when transmission occurs continuously during, or only at the end of, the infection period. Here, we used inbred lines of the macroparasitic spider mite Tetranychus urticae to disentangle genetic vs. nongenetic correlations among traits, while varying parasite density and opportunities for transmission. A positive genetic correlation between virulence and the number of transmitting stages produced was found under continuous transmission. However, if transmission occurred only at the end of the infection period, this genetic correlation disappeared. Instead, we observed a negative relationship between virulence and the number of transmitting stages, driven by density dependence. Thus, within-host density dependence caused by reduced opportunities for transmission may hamper selection for higher virulence, providing a novel explanation as to why limited host availability leads to lower virulence. [ABSTRACT FROM AUTHOR]

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]

Climate changes inevitably affect plant production, but it is difficult to predict their direct impact on a vitality (germination) of a produced seed. Germination is the most important indicator of seed vitality and a key stage in the life cycle of plants. Seed germination is significantly affected by environmental factors during the growing season, as well as the method of processing (according to seed size). The aim of this work was to determine the impact of three factors on seed germination of four sunflower inbred lines: i) genotype, ii) environment conditions in a production year, and iii) seed size obtained during processing. The germination was examined in a standard laboratory test by ISTA Ruls, six months after the processing and natural breaking of dormancy. Larger and smaller sizes seeds, obtained in two consecutive years, which were characterized by different environmental conditions (sum of precipitation, mean monthly temperatures and air humidity during flowering), were used. Collected data was analyzed using a three-way analysis of variance, and correlation analysis. The coefficient of variation was 8.19%. Significantly higher average seed germination was obtained during 2020 (92%,) compared to 2021 (85%). The effect of seed size was not statistically significant, regardless of the tested inbred line. It can be concluded that the increase in the seed germination of sunflower inbred lines is mainly influenced by genotype, but also the increase in precipitation, minimum and maximum air humidity during flowering and the decrease in mean monthly temperatures, which was confirmed by the correlation coefficients between the above agroecological conditions and the germination rate of the produced seeds.

IntroductionBiofortified maize varieties could contribute to the fight against hunger and malnutrition of the increasing human population and help meet the high demand of maize for human consumption, industrial use and feed for animal and poultry. The understanding of the genetic mechanisms conditioning the inheritance of grain yield and other agronomic and quality traits is essential in the development of superior maize genotypes. The main objective of this study was to determine the combining ability for grain yield and other agronomic traits of QPM and non-QPM inbred lines crossed with two QPM and two non-QPM testers.Materials and methodsA total of 130 hybrids were obtained by crossing 10 non-QPM and 23 QPM lines with four elite testers (two QPM and two non-QPM). The 130 single cross hybrids were evaluated at 13 sites in 2018 and 2019.Results and discussionThe results showed significant general combining ability (GCA) for lines and testers as well as significant specific combining ability (SCA) for hybrids for most of the measured traits. Non-additive gene action controlled the inheritance of grain yield while agronomic and quality traits were controlled by additive gene action. QPM lines 11, 14 and 28 and non-QPM tester CML444 showed desirable GCA effects for grain yield, indicating that these lines in combination with tester CML444 should be considered when targeting development of superior maize genotypes with QPM traits.ConclusionsBased on the SCA values, crosses 120, 108, 105, 99, 85, and 41 were identified as the best hybrids across the locations. It is recommended that maize breeding programs targeting the development of high yielding QPM hybrids should exploit QPM lines with high GCA values for heterosis to be realized. In addition, the identified superior hybrids may be further evaluated and consequently promoted for commercial release which could increase incomes of farmers and help to alleviate poverty, hunger and malnutrition in southern Africa and sub-Saharan Africa at large.

Seed vigor and seed germination are very important traits, determined by several factors including genetic and physical purity, mechanical damage, and physiological condition, characterized by maintaining a high seed vigor and stable content after storage. The search for molecular markers related to improvement in seed vigor under adverse condition is an important issue in maize breeding currently. Higher sowing quality of seeds is necessary for the development of the agriculture production and better ability to resist all kinds of adversity in the seeds' storage. Condition is a very important factor affecting the yield of plants, thanks to the construction of their vitality. Identification of molecular markers associated with seed germination and seed vigor may prove to be very important in the selection of high-yielding maize varieties. The aim of this study was to identify and select new markers for maize (SNP and SilicoDArT) linked to genes influencing the seed germination and seed vigor in inbred lines of maize (Zea mays L.). The plant material used for the research was 152 inbred maize lines. The seed germination and seed vigor were analyzed. For identification of SNP and SilicoDArT markers related to the seed germination and seed vigor, the SilicoDarT technique developed by Diversity Arrays Technology was used. The analysis of variance indicated a statistically significant differentiation between genotypes for both observed traits. Positive (r = 0.41) correlation (p < 0.001) between seed germination and seed vigor was observed. As a result of next-generation sequencing, the molecular markers SilicoDArT (53,031) and SNP (28,571) were obtained. Out of 81,602 identified SilicoDArT and SNP markers, 15,409 (1559 SilicoDArT and 13,850 SNP) were selected as a result of association mapping, which showed them to be significantly related to the analyzed traits. The 890 molecular markers were associated with seed vigor, and 1323 with seed germination. Fifty-six markers (47 SilicoDArT and nine SNP) were significant for both traits. Of these 56 markers, the 20 most significant were selected (five of these markers were significant at the level of 0.001 for seed vigor and at the level of 0.05 for seed germination, another five markers were significant at the level of 0.001 for seed germination and at the level of 0.05 for seed vigor, five markers significant at the level of 0.001 only for seed vigor and five significant at the level of 0.001 only for seed germination also selected). These markers were used for physical mapping to determine their location on the genetic map. Finally, it was found that six of these markers (five silicoDArT—2,435,784, 4,772,587, 4,776,334, 2,507,310, 25,981,291, and one SNP—2,386,217) are located inside genes, the action of which may affect both seed germination and seed vigor. These markers can be used to select genotypes with high vigor and good seed germination. [ABSTRACT FROM AUTHOR]

Globally, climate change could hinder future food security that concurrently implies the importance of investigating drought stress and genotype screening under stressed environments. Hence, the current study was performed to screen 45 diverse maize inbred lines for 18 studied traits comprising phenological, physiological, morphological, and yield characters under optimum and water stress conditions for two successive growing seasons (2018 and 2019). The results showed that growing seasons and water regimes significantly influenced (p < 0.01) most of the studied traits, while inbred lines had a significant effect (p < 0.01) on all of the studied traits. The findings also showed a significant increase in all studied characters under normal conditions compared to drought conditions, except chlorophyll content, transpiration rate, and proline content which exhibited higher levels under water stress conditions. Furthermore, the results of the principal component analysis indicated a notable distinction between the performance of the 45 maize inbred lines under normal and drought conditions. In terms of grain yield, the drought tolerance index (DTI) showed that Nub60 (1.56), followed by Nub32 (1.46), Nub66 (1.45), and GZ603 (1.44) were the highest droughttolerant inbred lines, whereas Nub46 (0.38) was the lowest drought-tolerant inbred line. These drought-tolerant inbred lines were able to maintain a relatively high grain yield under normal and stress conditions, whereas those drought-sensitive inbred lines showed a decline in grain yield when exposed to drought conditions. The hierarchical clustering analysis based on DTI classified the forty-five maize inbred lines and eighteen measured traits into three column- and row-clusters, as inbred lines in cluster-3 followed by those in cluster-2 exhibited greater drought tolerance in most of the studied traits. Utilizing the multi-trait stability index (MTSI) criterion in this study identified nine inbred lines, including GZ603, as stable genotypes in terms of the eighteen studied traits across four environments. The findings of the current investigation motivate plant breeders to explore the genetic potential of the current maize germplasm, especially in water-stressed environments. [ABSTRACT FROM AUTHOR]

Breeding for Al tolerance is the most sustainable strategy to reduce yield losses caused by Al toxicity in plants. The use of rapid, cheap and reliable testing methods and environments enables breeders to make quick selection decisions. The objectives of this study were to (i) identify high dry matter yielding and stable quality protein maize (QPM) lines grown under Al toxic and optimum conditions and (ii) compare the discriminating power of laboratory- and greenhouse-based testing environments. A total of 75 tropical QPM inbred lines were tested at seedling stage for dry matter yield and stability under optimum and Al toxic growing conditions across six laboratory- and greenhouse-based environments. The nutrient solution method was used for the laboratory trials, while the soil bioassay method was used for the greenhouse trials. A yield loss of 55% due to Al toxicity was observed, confirming the adverse effects of Al toxicity on maize productivity. The ANOVA revealed the presence of genetic variation among the set of genotypes used in this study, which can be exploited through plant breeding. Seventeen stable and high-yielding lines were identified and recommended. Greenhouse-based environments were more discriminating than laboratory environments. Therefore, we concluded that greenhouse environments are more informative than laboratory environments when testing genotypes for Al tolerance. [ABSTRACT FROM AUTHOR]

This investigation was carried out to study the combining ability effects of 13 parents of maize (10 inbred lines and 3 testers) crossed in line x tester scheme for earliness and yield characteristics. The trial included the 13 parents, 30 top crosses, along with the check hybrids SC 168. The experiment was conducted at two planting dates on 24 May and 14 June 2021 at the Agric. Res. and Experimental Station of the Fac. of Agric., Moshtohor Benha University. The experimental design was randomized complete blocks with three replications. Mean squares due to crosses (C) inbred lines (L), testers (T) and line x tester (LxT) were significant for most studied traits of both sowing dates as well as for the combined analysis. Significance of interaction variance for C, L, T and LxT with sowing dates for the most studied traits was detected. δ²SCA played the major role in determining the inheritance of all traits, revealing that the largest part of the total genetic variability associated with these traits was a result of non-additive gene action. The magnitude of the interaction of δ² SCA x sowing date (SD) was generally higher than for δ² GCA x SD. This finding indicates that non-additive type of gene action is more affected by SD than additive and additive x additive types of gene action. The cross L3xT10 was the earlier hybrid since it expressed the lowest values for days to 50% pollen shed (59.58), days to 50% silking (60.5) and days to maturity (91.33). The top crosses L4xT2, and L7xT1 in early sowing date, L1xT1, L2xT1, L3xT1, L2xT2,, L1xT3,, L2xT2,, L3xT1,, L3xT2,, L3xT3,, L5xT1,, L5xT2,, L6xT1, L6xT3, L7xT1, L8xT1, L9xT3 and L10xT2 in late sowing date and L3xT1, L4xT2, L7xT1, and L10xT2 in the combined across sowing date differed significantly from the check SC 168. [ABSTRACT FROM AUTHOR]

Avian viruses of economic interest are a significant burden on the poultry industry, affecting production traits and resulting in mortality. Furthermore, the zoonosis of avian viruses risks pandemics developing in humans. Vaccination is the most common method of controlling viruses; however current vaccines often lack cross‐protection against multiple strains of each virus. The mutagenicity of these viruses has also led to virulent strains emerging that can overcome the protection offered by vaccines. Breeding chickens with a more robust innate immune response may help in tackling current and emerging viruses. Understanding the genetic evolution of different lines will thus provide a useful tool in helping the host in the fight against pathogens. This study focuses on the interferon genes and their receptors in different chicken lines that are known to be more resistant or susceptible to particular avian viruses. Comparing genotypic differences in these core immune genes between the chicken lines may explain the phenotypic differences observed and aid the identification of causative variations. The relative resistance/susceptibility of each line to viruses of interest (Marek's disease virus, infectious bursal disease, infectious bronchitis virus and avian influenza virus) has previously been determined. Here we identify single nucleotide polymorphisms in interferons and downstream genes. Functional prediction tools were used to identify variants that may be affecting protein structure, mRNA secondary structure or transcription factor and micro‐RNA binding sites. These variants were then considered in the context of the research lines and their distribution between phenotypes. We highlight 60 variants of interest in the interferon pathway genes that may account for susceptibility/resistance to viral pathogens. [ABSTRACT FROM AUTHOR]

Relevance. Inbreeding is the most widespread method of obtaining starting breeding material and plays a central role in heterosis breeding programs of most crops. Beetroot inbred lines possessing economically valuable characteristics require constant maintenance via self-pollination. However, self-pollination leads to depression of a number of traits. Thorough theoretical studies and practical developments are needed to preserve valuable beetroot lines. We aimed to study the root and leaf rosette variability resulting from beetroot self-pollination. We also investigated the inheritance of monogermity in beetroots.Materials and methods. Experimental work was carried out at the All-Russian Research Institute of Vegetable Growing – branch of the Federal State Budgetary Scientific Institution "Federal Scientific Vegetable Center" (FSBSI FSVC), 2011-202], Moscow Region. The object of the study was inbred beetroot lines originated from beetroots of foreign selection. The research data were obtained via field observations and measurements.Results. It has been experimentally shown that the constant signs of self-pollinated beet lines of 1 year of life are the position and height of the leaf rosette. Stabilization and maintenance of separate fertility at a high level is carried out by selection. A negative correlation was noted between the signs of the degree of separateness and the height of the leaf rosette of the plant, the proportion of the neck of the root crop in its diameter, the mass of the root crop and the proportion of the root crop in the biomass of the plant in the offspring of the fourth generation of the inbreeding. The decrease in the productivity of the seed plant occurs at the beginning of the process of creating self-pollinated lines – in the first generation.