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Aim: Indole is an important component of many drug molecules, and its conjugation with thiosemicarbazone moiety would be advantageous in finding lead compounds for the development of diabetic complications. Methodology: We have designed, synthesized and evaluated a series of 17 indole-thiosemicarbazones (3a–q) as aldose reductase (ALR2) and aldehyde reductase (ALR1) inhibitors. Results: After in vitro evaluation, all indole-thiosemicarbazones showed significant inhibition against both enzyme ALR1 and ALR2 with IC50 in range of 0.42–20.7 and 1.02–19.1 μM, respectively. The docking study was also carried out to consider the putative binding of molecules with the target enzymes. Conclusion: Compound 3f was found to be most active and selective for ALR2. The indole-thiosemicarbazones series described here has selective hits for diabetes-mellitus-associated complications.

Background:Carbonic anhydrase II (CA-II) is associated with calcification, tumorigenicity, epilepsy, osteoporosis, and several other physiological or pathological processes. CA-II inhibitors can be used to reduce the intraocular pressure usually associated with glaucoma.Objective:In search for potent CA-II inhibitors, a series of thiosemicarbazone derivatives (3a-u) was synthesized.Methods:This series was evaluated against bovine and human carbonic anhydrase II (bCA-II and hCA-II) and their docking studies were carried out.Results:In the preliminary screening, most of the compounds exhibited significant inhibition of bCA-II and hCA-II. The predictive structure-activity relationship suggested that the thiosemicarbazide moiety plays a key role in the inhibition of enzyme activity and substitution at R position and has a remarkable contribution to the overall activity. The kinetic studies of the most active inhibitors of bCA-II (3d, 3e, 3l, 3f, and 3p) and hCA-II (3g) were performed against bCA-II and hCA-II, respectively to investigate their mode of inhibition and dissociation constants (Ki).Conclusion:Subsequently, (3e, 3f, 3l and 3p) were identified as competitive inhibitors of bCA-II with Ki values of 5.02-14.70 μM, while (3d) as a noncompetitive inhibitor of bCA-II (Ki = 2.5 ± 0.015 μM), however, (3g) demonstrated competitive inhibition of hCA-II with a Ki value of 5.95 ± 0.002 μM. The selectivity index reflects that compound (3g) is more selective for hCA-II. The binding modes of these compounds with bCA-II and hCA-II were investigated by structure-based molecular docking, and the docking results are in complete agreement with the experimental findings.

Drought adversely affects crop growth, development and yield. This study assessed genetic variation in a panel of wheat lines to water deficit and identified the QTLs governing this relationship via GWAS. A panel of 290 lines of the Wheat Association Mapping Initiative (WAMI) population were evaluated under well-irrigated and drought-stressed conditions. Stress tolerance indices were calculated to assess the response of wheat genotypes to water deficit. GWAS was performed using 15,737 SNP markers and six phenotypic traits. Evaluated traits were significantly affected across environments indicating variations in response to drought and ambient conditions. Heritability degrees were moderate to high and ranged from 0.39 to 0.93%. GWAS identified 205 significant marker-trait associations for the six studied phenotypic traits under well-irrigated and drought stress conditions. A positive correlation was found between drought stress index (STI) and plant grain yield (PGY) under both well-irrigated and stressed conditions. A linear relationship between STI and PGY under stressed conditions (PGYs) was observed. STI is the best index for prediction of high yielding genotypes. The WAMI population is a valuable source for improving drought tolerance in wheat. The study revealed significant marker–trait associations with a high degree of genetic diversity underlying different mechanisms for adaptation to drought-prone environments.

Three-dimensional high throughput plant phenotyping techniques provide an opportunity to measure plant organ-level traits which can be highly useful to plant breeders. The number and locations of cotton bolls, which are the fruit of cotton plants and an important component of fiber yield, are arguably among the most important phenotypic traits but are complex to quantify manually. Hence, there is a need for effective and efficient cotton boll phenotyping solutions to support breeding research and monitor the crop yield leading to better production management systems. We developed a novel methodology for 3D cotton boll mapping within a plot in situ. Point clouds were reconstructed from multi-view images using the structure from motion algorithm. The method used a region-based classification algorithm that successfully accounted for noise due to sunlight. The developed density-based clustering method could estimate boll counts for this situation, in which bolls were in direct contact with other bolls. By applying the method to point clouds from 30 plots of cotton plants, boll counts, boll volume and position data were derived. The average accuracy of boll counting was up to 90% and the R2 values between fiber yield and boll number, as well as fiber yield and boll volume were 0.87 and 0.66, respectively. The 3D boll spatial distribution could also be analyzed using this method. This method, which was low-cost and provided improved site-specific data on cotton bolls, can also be applied to other plant/fruit mapping analysis after some modification.

In this theoretical research, four donor molecules with diphenylamine subphthalocyanine (SubPc) as a common core, flanked with various electron-withdrawing groups at the central position containing Methyl-2-cyanoacrylate in C1, 3-methyl-5-methylene-2-thioxothiazolidin-4-one in C2, 2-(2-methylene-1-oxo-1H-inden-3(2H)-ylidene) malononitrile in C3, and Methyl-2-(5-methylene-4-oxo-2-thioxothiazoliden-3-yl) acetate in C4, have been designed. To analyze photovoltaic applications of all the studied molecules (C1-C4), quantum chemical simulations i.e., absorption profiles, frontier molecular orbitals (FMOs), the density of states (DOS), transition density matrix, and open-circuit voltage, have been performed availing DFT and TD-DFT approach with selected B3LYP functional /6-31G (d,p) level of theory. Among all the substituted molecules, C3 revealed highest molar absorption coefficient (601 nm), efficient electron density transfer in FMOs, and lowest energy band gap (1.70 eV) owing to the elongated conjugation along with the compelling electron-withdrawing nature of its axial acceptor moiety. All investigated molecules showed profound peaks in the visible region of the absorption spectrum as well as had low electron and hole mobilities in contrast to that of the reference (R) molecule. The observed binding energies (in electron-volt) of C2 (0.67), C3 (0.10), and C4 (0.47) molecules are found to be lower than R. Hence, these findings reveal that all designed candidates (C1-C4) could be effective and favorable applicants to enhance the energy efficiency of small molecule (SM) based organic solar cells (OSCs).

Aldose reductase is an important enzyme in the polyol pathway, where glucose is converted to fructose, and sorbitol is released. Aldose reductase activity increases in diabetes as the glucose levels increase, resulting in increased sorbitol production. Sorbitol, being less cell permeable tends to accumulate in tissues such as eye lenses, peripheral nerves and glomerulus that are not insulin sensitive. This excessive build-up of sorbitol is responsible for diabetes associated complications such as retinopathy and neuropathy. In continuation of our interest to design and discover potent inhibitors of aldo-keto reductases (AKRs; aldehyde reductase ALR1 or AKR1A, and aldose reductase ALR2 or AKR1B), herein we designed and investigated a series of new benzoxazinone-thiosemicarbazones (3a-r) as ALR2 and ALR1 inhibitors. Most compounds exhibited excellent inhibitory activities with IC50 values in lower micro-molar range. Compounds 3b and 3l were found to be most active ALR2 inhibitors with IC50 values of 0.52 ± 0.04 and 0.19 ± 0.03 μM, respectively, both compounds were more effective inhibitors as compared to the standard ALR2 inhibitor (sorbinil, with IC50 value of 3.14 ± 0.02 μM).

A new series of N-substituted thiosemicarbazones (3a-u) bearing 2-naphthyl and dihydrobenzofuranyl scaffolds were synthesized in good to excellent yields (78–95%). The synthesized compounds were characterized by advanced spectroscopic techniques, such as FTIR, 1HNMR, 13CNMR and ESI-MS and evaluated as urease inhibitors. The structure of compound 3m was unambiguously confirmed by single crystal X-ray analysis. All compounds showed remarkable activities against urease enzyme with IC50 values in range of 1.4–36.1 µM. The majority of the synthesized compounds showed higher activity than the standard compound thiourea. Molecular docking was performed to study the mode of interaction of these compounds and their structure-activity relationship. These studies revealed that the compounds bind at the active site and interacts with the nickel atom present in the binding site. The molecular docking demonstrated excellent co-relations with the experimental findings.

Inhibition of aldose reductase (ALR2) by using small heterocyclic compounds provides a viable approach for the development of new antidiabetic agents. With our ongoing interest towards aldose reductase (ALR2) inhibition, we have synthesized and screened a series of thiazoline derivatives (5a–k, 6a–f, 7a–1 & 8a–j) to find a lead as a potential new antidiabetic agent. The bioactivity results showed the thiazoline-based compound 7b having a benzyl substituent and nitrophenyl substituent-bearing compound 8e were identified as the most potent molecules with IC50 values of 1.39 ± 2.21 μM and 1.52 ± 0.78 μM respectively compared with the reference sorbinil with an IC50 value of 3.14 ± 0.02 μM. Compound 7b with only 23.4% inhibition for ALR1 showed excellent selectivity for the targeted ALR2 to act as a potential lead for the development of new therapeutic agents for diabetic complications.

The over expression of aldose reductase (ALR2) in the state of hyperglycemia causes the conversion of glucose into sorbitol and initiates polyol pathway. Accumulation of sorbitol in insulin insensitive tissue like peripheral nerves, glomerulus and eyes, induces diabetic complications like neuropathy, nephropathy and retinopathy. For the treatment of diabetic complications, the inhibition of aldose reductase (ALR2) is a promising approach. A series of coumarin-based thiosemicarbazone derivatives was synthesized as potential inhibitor of aldose reductase. Compound N-(2-fluorophenyl)-2-(1-(2-oxo-2H-chromen-3-yl)ethylidene)hydrazinecarbiothioamide (3n) was found to be the most promising inhibitor of ALR2 with an IC50 in micromolar range (2.07 µM) and high selectivity, relative to ALR1. The crystal structure of ALR2 complexed with 3n explored the types of interaction pattern which further demonstrated its high affinity. Compound 3n has excellent lead-likeness, underlined by its physicochemical parameters, and can be considered as a likely prospect for further structural optimization to get a drugable molecule.

Urease enzyme plays a key role in pathogenesis of gastritis and peptic ulcers. Its inhibition averts our bodies from many disorders including formation of urinary calculi. In agriculture, the high urease content causes severe environmental and hence economic problems. Due to deficiency of effective and safer drugs to tackle the aforementioned disorders, the quest for new scaffolds becomes mandatory in the field of medicinal chemistry. In this regard, we herein report a new series of N

The aim of the study was to estimate the magnitude of genetic variation through the characterization of germplasm using agronomical and morphological traits. In the current investigation 38 genotypes of chilli (Capsicum annuum) were evaluated at an agronomical and morphological level for (10 quantitative and 14 qualitative traits). A set of parameters covering different growth stages selected from the Capsicum descriptors developed by Biodiversity International Former. Qualitative traits were studied on a visual basis. Quantitative characters such as plant height ranged from 40 cm (36588) to 63 cm (36616). Fruit length and width range from 2.21 cm (36591) to 13.2 cm (36636) and 0.60 cm (36569) to 2.90 cm (36560 and 36441). Fruit weight varied from 0.85 g (36591) to 8.30 g (36651). Results obtained for yield/plant ranged from 175.49g (36652) to 780.3 g (36616). Results demonstrated the existence of diversity between the studied genotypes and consequently, providing the opportunity of attaining genetic advances in hybridization program for particular traits under consideration. Keywords: Agronomic traits; Chilli germplasm; Genetic diversity; Morphological traits http://dx.doi.org/10.19045/bspab.2020.90168

Extreme elongation distinguishes about one-fourth of cotton (Gossypium sp.) seed epidermal cells as “lint” fibers, useful for the textile industry, from “fuzz” fibers (

Euphorbia is one of the largest genera in the Euphorbiaceae family, comprising 2000 species possessing commercial, medicinal, and ornamental importance. However, there are very little data available on their molecular phylogeny and genomics, and uncertainties still exist at a taxonomic level. Herein, we sequence the complete chloroplast (cp) genomes of two species, E. larica and E. smithii, of the genus Euphorbia through next-generation sequencing and perform a comparative analysis with nine related genomes in the family. The results revealed that the cp genomes had similar quadripartite structure, gene content, and genome organization with previously reported genomes from the same family. The size of cp genomes ranged from 162,172 to 162,358 bp with 132 and 133 genes, 8 rRNAs, 39 tRNA in E. smithii and E. larica, respectively. The numbers of protein-coding genes were 85 and 86, with each containing 19 introns. The four-junction regions were studied and results reveal that rps19 was present at JLB (large single copy region and inverted repeat b junction) in E. larica where its complete presence was located in the IRb (inverted repeat b) region in E. smithii. The sequence comparison revealed that highly divergent regions in rpoC1, rpocB, ycf3, clpP, petD, ycf1, and ndhF of the cp genomes might provide better understanding of phylogenetic inferences in the Euphorbiaceae and order Malpighiales. Phylogenetic analyses of this study illustrate sister clades of E. smithii with E. tricullii and these species form a monophyletic clade with E. larica. The current study might help us to understand the genome architecture, genetic diversity among populations, and evolutionary depiction in the genera.

Drought is the most important yield limiting abiotic stress worldwide and could have negative effects on food security. This study was conducted to map yield and yield-contributing trait QTLs under drought stress by association mapping, and to in silico identify drought responsive genes and assay their expression profile. Association analysis was conducted using 181 SSR markers and nine phenotypic traits collected from a structured sorghum population consisting of 96 accessions evaluated under optimum and drought stressed conditions at Assiut University Experimental Farm, Assiut, Egypt. Genomic regions associated with major drought tolerance QTLs were annotated with NCBI and sorghum databases to identify drought responsive genes, which were further transcriptionally analyzed. Significant differences between optimum irrigation and drought-stressed conditions were observed in all measured phenotypic traits. Association analysis revealed 93 marker-trait associations between 71 SSR markers and the nine phenotypic traits with an R2 value ranging from 6.56 to 42.64%. A high degree of linkage disequilibrium (>52%) was identified among markers on different chromosomes, suggesting epistatic interaction. BLASTP annotation of QTL genomic sequences identified 86 gene homologs, from which fifteen genes are drought responsive. All fifteen genes were differentially expressed in drought tolerant and susceptible accessions and their expression levels were highly induced in response to drought stress. The results provide a powerful approach coupling association and in silico analyses to identify gene clusters having a common expression profile with similar function, pointing to an evolutionary mechanism to initiate a quantitative drought stress tolerance mechanism.

Charcoal rot disease, a root and stem disease caused by the soil-borne fungus Macrophomina phaseolina (Tassi) Goid., is a major biotic stress that limits sorghum productivity worldwide. Charcoal rot resistance-related parameters, e.g., pre-emergence damping-off%, post-emergence damping-off%, charcoal rot disease severity, and plant survival rates, were measured in a structured sorghum population consisting of 107 landraces. Analysis of variance of charcoal rot resistance-related parameters revealed significant variations in the response to M. phaseolina infection within evaluated accessions. Continuous phenotypic variations for resistance-related parameters were observed indicating a quantitative inheritance of resistance. The population was genotyped using 181 simple sequence repeat (SSR) markers. Association analysis identified 13 markers significantly associated with quantitative trait genes (QTLs) conferring resistance to charcoal rot disease with an R2 value ranging between 9.47 to 18.87%, nine of which are environment-specific loci. Several QTL-linked markers are significantly associated with more than one resistance-related parameter, suggesting that those QTLs might contain genes involved in the plant defense response. In silico analysis of four novel major QTLs identified 11 putative gene homologs that could be considered as candidate genes for resistance against charcoal rot disease. Cluster analysis using the genotypic data of 181 SSR markers from 107 sorghum accessions identified 12 main clusters. The results provide a basis for further functional characterization of charcoal rot disease resistance or defense genes in sorghum and for further dissection of their molecular mechanisms.

Background Autopolyploids refer to the increase in the genome from the same species, usually produced by direct doubling of diploid chromosomes. The polyploid formed by chromosome doubling of the same species is called homologous polyploid. Results In order to further check whether the Salicaceae-common tetraploid is homologous or heterologous, with grape as the outer group, by performing gene collinearity analysis, we explored whether two sets of poplar chromosomes or chromosomal regions have balanced gene expression levels and similar gene function. Paired T-test showed that duplicated genes in colinearity were balanced in expression, which is expected if the tetraploid ancestor was homologous whole-genome duplication, or autopolyploidization. Moreover, KEGG enrichment analysis and pathway annotation showed that most of the differentially expressed genes were related to metabolism. A comparison of different groups of flowering plants suggests that autopolyploidization may not provide comparable biological and evolutionary vigor to establish large plant groups, as observed in poaceae and brassicaceae families. The present analysis contributes to understanding the biology and evolution of Salicacea plants and beyond. Conclusions There was no significant difference in gene expression and gene function between two sets of genomes of poplar.

Urease enzyme plays a key role in pathogenesis of gastritis and peptic ulcers. Its inhibition averts our bodies from many disorders including formation of urinary calculi. In agriculture, the high urease content causes severe environmental and hence economic problems. Due to deficiency of effective and safer drugs to tackle the aforementioned disorders, the quest for new scaffolds becomes mandatory in the field of medicinal chemistry. In this regard, we herein report a new series of N4-substituted thiosemicarbazones 3a-v as potential candidates for urease inhibition. These new N4-substituted thiosemicarbazones 3a-v of distant chemical scaffolds were characterized by advanced spectroscopic techniques, such as FTIR, 1HNMR, 13CNMR, ESI-MS and in the case of compound 3g by single crystal X-ray analysis. The compounds were evaluated for their urease inhibitory potential. All newly synthesized compounds showed significant urease inhibitions with IC50 values in range of 2.7 ± 0.320–109.2 ± 3.217 μM. Molecular docking studies were used for interactions pattern and structure–activity relationship for all compounds, which demonstrated excellent binding interactions with the active site residues, such as hydrogen bonding, π–π interactions, π–H and nickel atom coordination.

The hyperactivity of urease enzyme is associated with clinically important complications including stomach ulcers and kidney stones. This enzyme provides a suitable environment to Helicobacter pylori at low pH in the stomach, a causative agent of peptic and ulcer gastric that may lead to cancer. Natural and synthetic small molecules were reported to inhibit urease enzyme. Within this context, a new series of 1,4-benzodioxane-based thiosemicarbazones (3a-p) were synthesized and screened in vitro against urease enzyme to elucidate their anti-urease activity. All the compounds displayed potent inhibitory potential with IC50 values ranging between 3.65 ± 2.64 to 31.9 ± 1.094 μM, under positive control of thiourea (IC50 = 20.8 ± 0.75 μM). Structural activity relationship (SAR) has revealed a variation based on substituents pattern at R group. The results of docking study suggest that these compounds thermodynamically binds via nickel atoms present in the active-site of urease. The in silico docking analysis and our experimental findings are in excellent co-relation. The pharmacokinetic behavior of all the compounds were also predicted.

A series of new hydrazonothiazolines (3a-v) was obtained in good to excellent yields (79–96%) via cyclization of the appropriate thiosemicarbazones with phenacyl bromide. The targeted compounds were characterized by advanced spectroscopic techniques, such as FTIR, 1HNMR, 13CNMR and ESI-MS. The structure of compounds 3n and 3v was unambiguously confirmed by single crystal X-ray analysis. All compounds displayed enhanced inhibitory activity against urease enzyme with IC50 values in range of 1.73 ± 1.57–27.3 ± 0.655 μM when compared to standard thiourea (IC50 = 20.8 ± 0.75 µM). The structure-activity relationship studies demonstrated that the activity of this series is due the central thiazole ring that interacts with nickel atoms in the active site of urease enzyme. Moreover, molecular docking studies were carried out to investigate the binding mode of all active compounds and an inactive (3u) with the active site of the urease enzyme. The docking results are in complete agreement with the experimental finding.

Commiphora gileadensis and C. foliacea (family Burseraceae) are pantropical in nature and known for producing fragrant resin (myrrh). Both the tree species are economically and medicinally important however, least genomic understanding is available for this genus. Herein, we report the complete chloroplast genome sequences of C. gileadensis and C. foliacea and comparative analysis with related species (C. wightii and Boswellia sacra). A modified chloroplast DNA extraction method was adopted, followed with next generation sequencing, detailed bioinformatics and PCR analyses. The results revealed that the cp genome sizes of C. gileadensis and C. foliacea, are 160,268 and 160,249 bp, respectively, with classic quadripartite structures that comprises of inverted repeat’s pair. Overall, the organization of these cp genomes, GC contents, gene order, and codon usage were comparable to other cp genomes in angiosperm. Approximately, 198 and 175 perfect simple sequence repeats were detected in C. gileadensis and C. foliacea genomes, respectively. Similarly, 30 and 25 palindromic, 15 and 25 forward, and 20 and 25 tandem repeats were determined in both the cp genomes, respectively. Comparison of these complete cp genomes with C. wightii and B. sacra revealed significant sequence resemblance and comparatively highest deviation in intergenic spacers. The phylo-genomic comparison showed that C. gileadensis and C. foliacea form a single clade with previously reported C. wightii and B. sacra from family Burseraceae. Current study reports for the first time the cp genomics of species from Commiphora, which could be helpful in understanding genetic diversity and phylogeny of this myrrh producing species.

In mapping populations segregating for many loci, the large amount of variation among genotypes often masks small-effect quantitative trait loci (QTL). This problem can be reduced by development of populations with fewer chromosome segments segregating. Here, we report early QTL detection in reciprocal advanced backcross populations from crosses between elite Gossypium hirsutum L. 'Acala Maxxa' (GH) and G. barbadense L. 'Pima S6' (GB). A total of 297 BCF and BCF progeny rows-127 segregating for GB chromosome segments in GH background and 170 segregating for GH chromosome segments in GB background-were evaluated in three environments. Totals of 3186 and 3026 polymorphic single-nucleotide polymorphisms (SNPs) in GH and GB backgrounds, respectively, were identified and used for trait mapping. Small-effect QTL (10% variance explained) made up 87 and 100% of QTL in GH and GB backgrounds, respectively. In both species, favorable alleles were found with effects being masked or neutralized by unfavorable alleles, with greater scope for improvement of GH than GB by introgressive breeding. A total of three stable QTL-two in GH background for fiber elongation (ELO) and micronaire (MIC) and one in GB background for upper-half mean length (UHM)-were identified in two out of three environments. Curiously, only four QTL-three for UHM and one for ELO-showed the expected opposite effects in reciprocal backgrounds, perhaps reflecting the combined consequences of epistasis, small phenotypic effects, and low coverage of some genomic regions. Along with new information for marker-assisted breeding, this study adds to knowledge that can be used to unravel complex genetic networks governing fiber quality traits.

The molecular genetic basis of cotton fiber strength and fineness in crosses between Gossypium mustelinum and Gossypium hirsutum (Upland cotton) was dissected using 21 BC3F2 and 12 corresponding BC3F2:3 and BC3F2:4 families. The BC3F2 families were genotyped with simple sequence repeat markers from a G. hirsutum by G. mustelinum linkage map, and the three generations of BC3-derived families were phenotyped for fiber strength (STR) and fineness (Micronaire, MIC). A total of 42 quantitative trait loci (QTLs) were identified through one-way analysis of variance, including 15 QTLs for STR and 27 for MIC, with the percentage of variance explained by individual loci averaging 13.86 and 14.06%, respectively. Eighteen of the 42 QTLs were detected at least twice near the same markers in different generations/families or near linked markers in the same family, and 28 of the 42 QTLs were identified in both mixed model-based composite interval mapping and one-way variance analyses. Alleles from G. mustelinum increased STR for eight of 15 and reduced MIC for 15 of 27 QTLs. Significant among-family genotypic effects (P < 0.001) were detected in 13 and 10 loci for STR and MIC respectively, and five loci showed significant (P < 0.001) genotype × family interaction for MIC. These results support the hypothesis that fiber quality improvement for Upland cotton could be realized by introgressing G. mustelinum alleles although complexities due to the different effects of genetic background on introgressed chromatin might be faced. Building on prior work with G. barbadense, G. tomentosum, and G. darwinii, QTL mapping involving introgression of G. mustelinum alleles offers new allelic variation to Upland cotton germplasm.

Two hundred ninety­six Asian barley (Hordeum vulgare L.) accessions were assessed to detect QTLs underlying salt tolerance by association analysis using a 384 single nucleotide polymorphism (SNP) marker system. The experiment was laid out at the seedling stage in a hydroponic solution under control and 250 mM NaCl solution with three replications of four plants each. Salt tolerance was assessed by leaf injury score (LIS) and salt tolerance indices (STIs) of the number of leaves (NL), shoot length (SL), root length (RL), shoot dry weight (SDW) and root dry weight (RDW). LIS was scored from 1 to 5 according to the severity of necrosis and chlorosis observed on leaves. There was a wide variation in salt tolerance among Asian barley accessions. LIS and STI (SDW) were the most suitable traits for screening salt tolerance. Association was estimated between markers and traits to detect QTLs for LIS and STI (SDW). Seven significant QTLs were located on chromosomes 1H (2 QTLs), 2H (2 QTLs), 3H (1 QTL), 4H (1 QTL) and 5H (1 QTL). Five QTLs were asso­ ciated with LIS and 2 QTLs with STI (SDW). Two QTLs associated with LIS were newly identified on chromosomes 3H and 4H.

In recent years, sorghum (Sorghum bicolor (L.) Moench) has gained attention as a food, feed, and biofuel crop, but yield improvements have lagged behind those in other crops. Here, we investigated quantitative trait loci (QTLs) associated with yield and yield-related traits in sorghum. We measured eight morphological traits related to yield potential in an F2 and F2:3 population derived from a cross between African and Japanese sorghum landraces, and we developed a genetic linkage map of 137 sorghum genome-based simple sequence repeat markers. The total map length was 1,239.2 cM, with an average distance of 9.9 cM between adjacent markers. By using both single- and multiple-QTL approaches to identify the chromosomal regions controlling these traits, we identified a total of 52 QTLs associated with the eight traits (culm length, number of tillers, panicle length, culm diameter, leaf length, leaf width, grain weight/panicle, and 100-grain weight) using F2 phenotypic values while 25 QTLs were confirmed in the F2:3 population. The percentage phenotypic variation explained by individual QTLs ranged from 3.1 to 36.3 % in the F2 and 2.1 to 30.4 % in the F2:3 population. Most of the traits were significantly correlated with one another (P

Salinity is globally a major constraint for crop production. Breeding for salinity tolerance is an effective approach to improve crop production and productivity under saline conditions provided it is based on a good understanding of the genetic control of salinity tolerance. This study deals with mapping QTLs for salinity tolerance in durum wheat (Triticum durum) by association analysis using SSR markers. A total of 119 varieties were treated in 100 mM of NaCl solution and the salinity tolerance indices (STI) for several traits were calculated as parameters to assess salinity tolerance. Among the traits assessed, the increased proportion of dead leaves (%DL) was the most suitable parameter for assessment of salinity tolerance in durum varieties at early vegetative stages because of a broader range of variation among varieties and narrower range of variation within varieties compared to other traits. The QTL associated with salinity tolerance using %DL as a parameter was detected on chromosome 4B. An additional 11 QTLs associated with seven parameters using STI of other traits were detected on chromosomes 3A, 5A, 5B, 6A and 7A.

The pattern of the panicle is an important characteristic of sorghum that is used to identify race divisions and species values. The knowledge of the genetic basis of sorghum inflorescence architecture and its component traits can enhance the process of improvement in sorghum breeding. This study was undertaken to better understand the genetic basis of sorghum inflorescence architecture and its association with yield-related traits. We investigated 98 simple sequence repeat maps in the sorghum diversity research set (SDRS) of 107 landraces from the worldwide sorghum germplasm. A significant difference between accessions was observed for 14 measured traits. In several components of sorghum inflorescence architecture, we found that the significance and high correlations between pairs of traits revealed that these variations are dependent not only on the panicle length (PanL) but also on the total branch number, maximum length of the primary branch (MaxLBZ/MxLBZ) , rachis length (Rac), and panicle diameter (PanD) and width (Panw). Significant mean squares were obtained for almost all characters in the individual analysis and combined analysis of variance for each season and across two seasons, suggesting that, the components of inflorescence architecture and yield related traits were highly variable in SDRS population, therefore, would respond to selection for yield improvement. Molecular markers divided the germplasm into three sub-populations with different groups of inflorescence/panicle types (PanT) (broom, open and compact). The SDRS was composed of six different PanT that were associated with 14 inflorescence traits. Using different models of association analysis, 16 loci on 8 chromosomes were found to be significantly related to the patterns of observed panicle traits. Among these loci, four QTLs were responsible for length-based traits, and three QTLs were responsible for dimentional traits. Four QTLs were responsible for panicle feature such as PanT and shape, one QTL responsible for yield related trait such as grain weight. Two QTLs were responsible for branch-based traits, such as the total node number and branch number with −Log10 (P) values ranging from 1.5 to 7.6 as the threshold value. Several genomic regions affected multiple traits, including one region that affected PanL and MxLBZ/MaxLBZ. QTLs for different traits tended to be found in the same region on chromosome 4 and on chromosome 9. Additionally, QTL was involved on Chr-2, Chr-5, Chr-6 and Chr-10 as a novel QTL that controlled Rac, total node number, PanD and PanT. These results will serve as preliminary findings of QTLs for sorghum inflorescence architecture, and a further evaluation of the germplasm for these traits is in progress. Moreover, these findings can lead to the emergence of a new era of sorghum genomics, which are aimed at bridging the knowledge gap between genotype and phenotype in sorghum inflorescence architecture.

This study was conducted to identify quantitative trait loci (QTLs) for drought tolerance in sorghum (Sorghum bicolor (L.) Moench) by association mapping using a simple sequence repeat (SSR)-marker-based diversity research set. Genotypic data for 98 SSR marker loci on ten chromosomes were used for the association analysis. The experiment was conducted under control (well-watered) and drought stress conditions, and the phenotypic values of 23 morphological traits were recorded. Drought tolerance was assessed by using a leaf drying score as a parameter of the tolerance/susceptibility: scores were assigned on a scale from 1 (most tolerant) to 9 (most susceptible). Under the control conditions, 17 QTLs associated with 12 traits were identified on chromosomes 1, 2, 4, 8, 9, and 10, with −Log10 (P) ranging from 2.5 to 7.6 and explaining 9.5–57.5 % of the total phenotypic variance for the traits. Under the drought stress conditions, nine QTLs associated with 8 traits were identified on chromosomes 1, 2, 3, and 10 that explained 9–61.2 % of the total phenotypic variance for the traits, with −Log10 (P) ranging from 2.5 to 3.5. QTLs for some traits were detected only under the drought stress condition, suggesting that these traits are important in drought tolerance. These QTLs could be used to further dissect the genetic and physiological basis of drought tolerance in sorghum.

This study was undertaken to analyse the variation in panicle-related traits of 206 sorghum accessions collected from 27 Asian and African countries. Significant differences among the accessions were observed for 18 measured traits. First, we found that the patterns of the observed panicle-related traits reflected the distribution of the accessions of different origins. Second, the distribution of several components of inflorescence architecture in sorghum accessions influenced their yield components. Principal component analysis of the data showed a wide range of variations across the 206 sorghum accessions. Despite their geographical isolation, no distinct separation between the Asian and African accessions was observed. Correlation coefficient and path coefficient analysis indicated that panicle length (PanL), the total number of branches, rachis length (Rac) and panicle width had a positive direct effect on grain yield. Finally, we showed that the variation in the inflorescence architecture of sorghum accessions was dependent not only on the PanL, but also on the total number of branches, the maximum length of primary branches, Rac, panicle diameter and panicle width. Thus, there are major panicle determinants that are strongly associated with grain yield which should be considered in breeding programmes. These results will serve as a starting point for further evaluation of sorghum germplasm via quantitative trait loci analysis and may be useful for improving yield based on careful consideration of trait selection and inflorescence morphology.