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In this article, we prove the infinitude of the non‐trivial zeroes of Koecher–Maass series associated to a Siegel cusp form of weight k$k$ and degree 2 on the critical line. [ABSTRACT FROM AUTHOR]

Iron deficiency chlorosis is an important abiotic stress affecting groundnut production worldwide in calcareous and alkaline soils with a pH of 7.5–8.5. To identify genomic regions controlling iron deficiency chlorosis resistance in groundnut, the recombinant inbred line population from the cross TAG 24 × ICGV 86031 was evaluated for associated traits like visual chlorosis rating and SPAD chlorophyll meter reading across three crop growth stages for two consecutive years. Thirty‐two QTLs were identified for visual chlorosis rating (3.9%–31.8% phenotypic variance explained [PVE]) and SPAD chlorophyll meter reading [3.8%–11% PVE] across three stages over 2 years. This is the first report of identification of QTLs for iron deficiency chlorosis resistance‐associated traits in groundnut. Three major QTLs (>10% PVE) were identified at severe stage, while majority of other QTLs were having small effects. Interestingly, two major QTLs for visual chlorosis rating at 60 days (2013) and 90 days (2014) were located at same position on LG AhXIII. The identified QTLs/markers after validation across diverse genetic material could be used in genomics‐assisted breeding. [ABSTRACT FROM AUTHOR]

Summary: Bacterial wilt, caused by Ralstonia solanacearum, is a devastating disease affecting over 350 plant species. A few peanut cultivars were found to possess stable and durable bacterial wilt resistance (BWR). Genomics‐assisted breeding can accelerate the process of developing resistant cultivars by using diagnostic markers. Here, we deployed sequencing‐based trait mapping approach, QTL‐seq, to discover genomic regions, candidate genes and diagnostic markers for BWR in a recombination inbred line population (195 progenies) of peanut. The QTL‐seq analysis identified one candidate genomic region on chromosome B02 significantly associated with BWR. Mapping of newly developed single nucleotide polymorphism (SNP) markers narrowed down the region to 2.07 Mb and confirmed its major effects and stable expressions across three environments. This candidate genomic region had 49 nonsynonymous SNPs affecting 19 putative candidate genes including seven putative resistance genes (R‐genes). Two diagnostic markers were successfully validated in diverse breeding lines and cultivars and could be deployed in genomics‐assisted breeding of varieties with enhanced BWR. [ABSTRACT FROM AUTHOR]

Summary: Cultivated peanut (Arachis hypogaea L.) is an important grain legume providing high‐quality cooking oil, rich proteins and other nutrients. Shelling percentage (SP) is the 2nd most important agronomic trait after pod yield and this trait significantly affects the economic value of peanut in the market. Deployment of diagnostic markers through genomics‐assisted breeding (GAB) can accelerate the process of developing improved varieties with enhanced SP. In this context, we deployed the QTL‐seq approach to identify genomic regions and candidate genes controlling SP in a recombinant inbred line population (Yuanza 9102 × Xuzhou 68‐4). Four libraries (two parents and two extreme bulks) were constructed and sequenced, generating 456.89–790.32 million reads and achieving 91.85%–93.18% genome coverage and 14.04–21.37 mean read depth. Comprehensive analysis of two sets of data (Yuanza 9102/two bulks and Xuzhou 68‐4/two bulks) using the QTL‐seq pipeline resulted in discovery of two overlapped genomic regions (2.75 Mb on A09 and 1.1 Mb on B02). Nine candidate genes affected by 10 SNPs with non‐synonymous effects or in UTRs were identified in these regions for SP. Cost‐effective KASP (Kompetitive Allele‐Specific PCR) markers were developed for one SNP from A09 and three SNPs from B02 chromosome. Genotyping of the mapping population with these newly developed KASP markers confirmed the major control and stable expressions of these genomic regions across five environments. The identified candidate genomic regions and genes for SP further provide opportunity for gene cloning and deployment of diagnostic markers in molecular breeding for achieving high SP in improved varieties. [ABSTRACT FROM AUTHOR]

Rust and late leaf spot ( LLS) are the two major foliar fungal diseases in groundnut, and their co-occurrence leads to significant yield loss in addition to the deterioration of fodder quality. To identify candidate genomic regions controlling resistance to rust and LLS, whole-genome resequencing ( WGRS)-based approach referred as ' QTL-seq' was deployed. A total of 231.67 Gb raw and 192.10 Gb of clean sequence data were generated through WGRS of resistant parent and the resistant and susceptible bulks for rust and LLS. Sequence analysis of bulks for rust and LLS with reference-guided resistant parent assembly identified 3136 single-nucleotide polymorphisms ( SNPs) for rust and 66 SNPs for LLS with the read depth of ≥7 in the identified genomic region on pseudomolecule A03. Detailed analysis identified 30 nonsynonymous SNPs affecting 25 candidate genes for rust resistance, while 14 intronic and three synonymous SNPs affecting nine candidate genes for LLS resistance. Subsequently, allele-specific diagnostic markers were identified for three SNPs for rust resistance and one SNP for LLS resistance. Genotyping of one RIL population ( TAG 24 × GPBD 4) with these four diagnostic markers revealed higher phenotypic variation for these two diseases. These results suggest usefulness of QTL-seq approach in precise and rapid identification of candidate genomic regions and development of diagnostic markers for breeding applications. [ABSTRACT FROM AUTHOR]

Peanut (Arachis hypogaea L.) is an important self-pollinating tetraploid (AABB, 2n = 4x = 40) legume grown for the high-quality edible oil and easily digestible protein in its seeds. Enormous genetic variability is present in the genus Arachis containing 79 wild species and cultivated peanut. Wild species offer significant variability, particularly for biotic and abiotic stresses, and can be used to develop cultivars with enhanced levels of resistance to key stresses. However, utilization of these species requires use of ploidy manipulations, bridge crosses, and embryo or ovule rescue. For efficient use of diploid wild species from section Arachis, several synthetics (amphidiploids and autotetraploids) have been developed using A- and B-genome accessions with high levels of resistance to multiple stresses. These synthetics are used in crossing programs with cultigens to develop prebreeding populations and introgression lines (ILs) with high frequency of useful genes and alleles into good agronomic backgrounds. Evaluation of two such populations derived from ICGV 91114 x ISATGR 121250 (a synthetic derived from A. duranensis Krapov. & W.C. Greg. x A. ipaensis Krapov. & W.C. Greg.) and ICGV 87846 x ISATGR 265-5 (A. kempf-mercadoi W.C. Greg. & C.E. Simpson x A. hoehnei Krapov. & W.C. Greg.) resulted in the identification of ILs with high levels of late leaf spot (LLS) and rust resistance and significant genetic variability for morphoagronomic traits. Genotyping of these ILs with markers linked to rust and LLS resistance provided evidence that introgression of possible novel alleles and resistance sources from different wild species other than the commonly used A. cardenasii Krapov. & W.C. Greg. will be beneficial for peanut improvement. [ABSTRACT FROM AUTHOR]

Seed quality for both germination in the next generation and for human consumption is adversely affected due to preharvest sprouting in peanut. It also makes seeds more vulnerable to infection by a number of pathogens. Therefore, it is desirable to have 2-3 weeks of fresh seed dormancy ( FSD) in the peanut varieties. In this context, one F2 population was developed from a cross between non-dormant ( ICGV 00350) and dormant ( ICGV 97045) genotypes. Phenotyping of this population showed control of the trait by two recessive genes. In parallel, genotyping of the population with Diversity Arrays Technology ( DArT) and DArT-seq markers provided a genetic map with 1152 loci covering a map distance of 2423.12 cM and map density of 2.96 cM/loci. Quantitative trait locus ( QTL) analysis identified two major QTLs, namely qfsd-1 and qfsd-2 explaining 22.14% and 71.21% of phenotypic variation, respectively. These QTLs, after validation in different genetic backgrounds, may be useful for molecular breeding for FSD in peanut. [ABSTRACT FROM AUTHOR]

Introgression lines ( ILs) of groundnut with enhanced resistance to rust and late leaf spot ( LLS) recorded increased pod and haulm yield in multilocation testing. Marker-assisted backcrossing ( MABC) approach was used to introgress a genomic region containing a major QTL that explains >80% of phenotypic variance ( PV) for rust resistance and 67.98% PV for LLS resistance. ILs in the genetic background of TAG 24, ICGV 91114 and JL 24 were evaluated for two seasons to select 20 best ILs based on resistance, productivity parameters and maturity duration. Multilocation evaluation of the selected ILs was conducted in three locations including disease hot spots. Background genotype, environment and genotype × environment interactions are important for expression of resistance governed by the QTL region. Six best ILs namely ICGV 13192, ICGV 13193, ICGV 13200, ICGV 13206, ICGV 13228 and ICGV 13229 were selected with 39-79% higher mean pod yield and 25-89% higher mean haulm yield over their respective recurrent parents. Pod yield increase was contributed by increase in seed mass and number of pods per plant. [ABSTRACT FROM AUTHOR]

For 15 European countries over the 1970-2004 period we find large and persistent agricultural productivity gaps, the ratio of value added per hour in nonagriculture to that in agriculture. Comparing the gap in value added per hour to the wage gap between the two sectors suggests that value added in the data is mismeasured. We further find that, controlling for differences in gross domestic product per capita and institutions, the mismeasurement is positively related to self-employed share of hours in agriculture. Correcting for underreporting of self-employment income using our preferred correction factor reduces the measured agricultural productivity gap by 38%. These findings suggest that underreporting can account for a significant portion of the measured agricultural productivity gap. ( JEL E01, O47, O52, Q10) [ABSTRACT FROM AUTHOR]

Summary: Professor Rajeev K. Varshney's transformative impact on crop genomics, genetics, and agriculture is the result of his passion, dedication, and unyielding commitment to harnessing the potential of genomics to address the most pressing challenges faced by the global agricultural community. Starting from a small town in India and reaching the global stage, Professor Varshney's academic and professional trajectory has inspired many scientists active in research today. His ground‐breaking work, especially his effort to list orphan tropical crops to genomic resource‐rich entities, has been transformative. Beyond his scientific achievements, Professor Varshney is recognized by his colleagues as an exemplary mentor, fostering the growth of future researchers, building institutional capacity, and strengthening scientific capability. His focus on translational genomics and strengthening seed system in developing countries for the improvement of agriculture has made a tangible impact on farmers' lives. His skills have been best utilized in roles at leading research centres where he has applied his expertise to deliver a new vision for crop improvement. These efforts have now been recognized by the Royal Society with the award of the Fellowship (FRS). As we mark this significant milestone in his career, we not only celebrate Professor Varshney's accomplishments but also his wider contributions that continue to transform the agricultural landscape. [ABSTRACT FROM AUTHOR]

Tuning the open‐circuit voltage (VOC) and fill factor (FF) without sacrificing the short‐circuit current density is crucial for achieving performance advantages in ternary blend organic solar cells as an alternative to the binary ones. This study investigates ternary all‐polymer solar cells comprised of two polymer donors (D1 and D2) and one polymer acceptor (A), using two types of D2 polymers with different compatibilities with D1. As demonstrated by photoelectron yield spectroscopy, the ionization energy (IE) of the ternary blends continuously shifts between the IEs of D1:A and D2:A binary blends when D2 forms a single indistinguishable domain with D1. In contrast, the IE of the blends does not exhibit any noticeable change when D2 induces distinct phase separation with D1. Models describing the blend composition dependence of the VOC and FF are constructed by correlating the effects of the blend morphology and the shift in the energy level of the hole‐transporting state in the ternary blends. This study demonstrates that a pseudo‐binary blend morphology with a mixed D1 and D2 donor domain and an A acceptor domain is necessary to obtain a broad tunability of VOC and tolerance of FF to the blend composition in ternary all‐polymer solar cells. [ABSTRACT FROM AUTHOR]

Summary: The transcriptome connects genome to the gene function and ultimate phenome in biology. So far, transcriptomic approach was not used in peanut for performing trait mapping in bi‐parental populations. In this research, we sequenced the whole transcriptome in immature seeds in a peanut recombinant inbred line (RIL) population and explored thoroughly the landscape of transcriptomic variations and its genetic basis. The comprehensive analysis identified total 49 691 genes in RIL population, of which 92 genes followed a paramutation‐like expression pattern. Expression quantitative trait locus (eQTL) analysis identified 1207 local eQTLs and 15 837 distant eQTLs contributing to the whole‐genome transcriptomic variation in peanut. There were 94 eQTL hot spot regions detected across the genome with the dominance of distant eQTL. By integrating transcriptomic profile and annotation analyses, we unveiled a putative candidate gene and developed a linked marker InDel02 underlying a major QTL responsible for purple testa colour in peanut. Our result provided a first understanding of genetic basis of whole‐genome transcriptomic variation in peanut and illustrates the potential of the transcriptome‐aid approach in dissecting important traits in non‐model plants. [ABSTRACT FROM AUTHOR]

Summary: Whole‐genome resequencing (WGRS) of mapping populations has facilitated development of high‐density genetic maps essential for fine mapping and candidate gene discovery for traits of interest in crop species. Leaf spots, including early leaf spot (ELS) and late leaf spot (LLS), and Tomato spotted wilt virus (TSWV) are devastating diseases in peanut causing significant yield loss. We generated WGRS data on a recombinant inbred line population, developed a SNP‐based high‐density genetic map, and conducted fine mapping, candidate gene discovery and marker validation for ELS, LLS and TSWV. The first sequence‐based high‐density map was constructed with 8869 SNPs assigned to 20 linkage groups, representing 20 chromosomes, for the 'T' population (Tifrunner × GT‐C20) with a map length of 3120 cM and an average distance of 1.45 cM. The quantitative trait locus (QTL) analysis using high‐density genetic map and multiple season phenotyping data identified 35 main‐effect QTLs with phenotypic variation explained (PVE) from 6.32% to 47.63%. Among major‐effect QTLs mapped, there were two QTLs for ELS on B05 with 47.42% PVE and B03 with 47.38% PVE, two QTLs for LLS on A05 with 47.63% and B03 with 34.03% PVE and one QTL for TSWV on B09 with 40.71% PVE. The epistasis and environment interaction analyses identified significant environmental effects on these traits. The identified QTL regions had disease resistance genes including R‐genes and transcription factors. KASP markers were developed for major QTLs and validated in the population and are ready for further deployment in genomics‐assisted breeding in peanut. [ABSTRACT FROM AUTHOR]

The advection–dispersion equation (ADE) is one of the most widely used methods for estimating natural stream pollution at different locations and times. In this paper, variational iteration method (VIM) is utilized to obtain a semi‐analytical solution for 1D ADE in a temporally dependent solute dispersion within uniformsteady flow. Through a computational validation, the effect of different parameters such as uniform flow velocity and dispersion coefficient on the solute concentration values has been investigated. Results show that the change in velocity has a strong effect on fluid density variation. However, when the diffusion coefficient has been increased, the change in flow and velocity behaviors is negligible. To verify the proposed semianalytical solution, the results were compared to analytical solutions and errors were found to be <0.7% in all simulations. [ABSTRACT FROM AUTHOR]

Two elite cultivars of peanut (Arachis hypogaea L.), GPBD 4 and G 2–52, with high productivity, oil content, resistance to late leaf spot [Phaeoisariopsis personata (Berk. & Curt) V. Arx.] (LLS) and rust (Puccinia arachidis Speg.) diseases were improved for oleic acid content using marker‐assisted backcrossing. Since both the recurrent parents already possessed the mutant allele at AhFAD2A, only mutant allele at AhFAD2B was transferred from the donor 'SunOleic 95R' (oleate of 80.6%). Three rounds of backcrossing with foreground selection using allele‐specific polymerase chain reaction (PCR) and Kompetitive allele‐specific PCR (KASP) assay identified a large number of plants homozygous for the mutant allele at AhFAD2B in BCnF2 generations. Evaluation of the advanced generations could identify six and 10 lines with significantly higher oleate than GPBD 4 and G 2–52, respectively. Considering the yield, shelling percentage, oil, and oleate content, the most promising lines HOBC2GPS_7 and HOBC2G2S_5 were selected with 112 and 142% oleate recovery over GPBD 4 and G 2–52, respectively. Double digest restriction‐site‐associated DNA sequencing of these superior lines showed background genome recovery of 77.5 and 69.0%, respectively. These advanced breeding lines with high oleate (∼80%), resistance to LLS and rust and high productivity are under further trials for possible release as varieties for commercial cultivation. Core Ideas: Peanut is a rich source of oil, proteins, and carbohydrates, known as "poor man's almond".Peanut with high oleic acid content offers oil stability, flavor, and several health benefits.We have improved two elite peanut varieties for oleic acid content using MABC approach.Field evaluation of high oleate backcross lines confirmed higher productivity and disease resistance. [ABSTRACT FROM AUTHOR]

Summary: Spatio‐temporal and developmental stage‐specific transcriptome analysis plays a crucial role in systems biology‐based improvement of any species. In this context, we report here the Arachis hypogaea gene expression atlas (AhGEA) for the world's widest cultivated subsp. fastigiata based on RNA‐seq data using 20 diverse tissues across five key developmental stages. Approximately 480 million paired‐end filtered reads were generated followed by identification of 81 901 transcripts from an early‐maturing, high‐yielding, drought‐tolerant groundnut variety, ICGV 91114. Further, 57 344 genome‐wide transcripts were identified with ≥1 FPKM across different tissues and stages. Our in‐depth analysis of the global transcriptome sheds light into complex regulatory networks namely gravitropism and photomorphogenesis, seed development, allergens and oil biosynthesis in groundnut. Importantly, interesting insights into molecular basis of seed development and nodulation have immense potential for translational genomics research. We have also identified a set of stable expressing transcripts across the selected tissues, which could be utilized as internal controls in groundnut functional genomics studies. The AhGEA revealed potential transcripts associated with allergens, which upon appropriate validation could be deployed in the coming years to develop consumer‐friendly groundnut varieties. Taken together, the AhGEA touches upon various important and key features of cultivated groundnut and provides a reference for further functional, comparative and translational genomics research for various economically important traits. [ABSTRACT FROM AUTHOR]

Summary: Multiparental genetic mapping populations such as nested‐association mapping (NAM) have great potential for investigating quantitative traits and associated genomic regions leading to rapid discovery of candidate genes and markers. To demonstrate the utility and power of this approach, two NAM populations, NAM_Tifrunner and NAM_Florida‐07, were used for dissecting genetic control of 100‐pod weight (PW) and 100‐seed weight (SW) in peanut. Two high‐density SNP‐based genetic maps were constructed with 3341 loci and 2668 loci for NAM_Tifrunner and NAM_Florida‐07, respectively. The quantitative trait locus (QTL) analysis identified 12 and 8 major effect QTLs for PW and SW, respectively, in NAM_Tifrunner, and 13 and 11 major effect QTLs for PW and SW, respectively, in NAM_Florida‐07. Most of the QTLs associated with PW and SW were mapped on the chromosomes A05, A06, B05 and B06. A genomewide association study (GWAS) analysis identified 19 and 28 highly significant SNP–trait associations (STAs) in NAM_Tifrunner and 11 and 17 STAs in NAM_Florida‐07 for PW and SW, respectively. These significant STAs were co‐localized, suggesting that PW and SW are co‐regulated by several candidate genes identified on chromosomes A05, A06, B05, and B06. This study demonstrates the utility of NAM population for genetic dissection of complex traits and performing high‐resolution trait mapping in peanut. [ABSTRACT FROM AUTHOR]

Summary: The subspecies fastigiata of cultivated groundnut lost fresh seed dormancy (FSD) during domestication and human‐made selection. Groundnut varieties lacking FSD experience precocious seed germination during harvest imposing severe losses. Development of easy‐to‐use genetic markers enables early‐generation selection in different molecular breeding approaches. In this context, one recombinant inbred lines (RIL) population (ICGV 00350 × ICGV 97045) segregating for FSD was used for deploying QTL‐seq approach for identification of key genomic regions and candidate genes. Whole‐genome sequencing (WGS) data (87.93 Gbp) were generated and analysed for the dormant parent (ICGV 97045) and two DNA pools (dormant and nondormant). After analysis of resequenced data from the pooled samples with dormant parent (reference genome), we calculated delta‐SNP index and identified a total of 10,759 genomewide high‐confidence SNPs. Two candidate genomic regions spanning 2.4 Mb and 0.74 Mb on the B05 and A09 pseudomolecules, respectively, were identified controlling FSD. Two candidate genes—RING‐H2 finger protein and zeaxanthin epoxidase—were identified in these two regions, which significantly express during seed development and control abscisic acid (ABA) accumulation. QTL‐seq study presented here laid out development of a marker, GMFSD1, which was validated on a diverse panel and could be used in molecular breeding to improve dormancy in groundnut. [ABSTRACT FROM AUTHOR]

Parents and 318 F8 recombinant inbred lines (RILs) derived from the cross, TAG 24 × ICGV 86031 were evaluated for peanut bud necrosis disease (PBND) resistance and agronomic traits under natural infestation of thrips at a disease hotspot location for 2 years. Significant genotype, environment and genotype × environment interaction effects suggested role of environment in development and spread of the disease. Quantitative trait loci (QTL) analysis using QTL Cartographer identified a total of 14 QTL for six traits of which five QTL were for disease incidence. One quantitative trait locus q60DI located on LG_AhII was identified using both QTL Cartographer and QTL Network. Another QTL q90DI was detected with a high PVE of 12.57 using QTL Cartographer. A total of nine significant additive × additive (AA) interactions were detected for PBND disease incidence and yield traits with two and seven interactions displaying effects in favour of the parental and recombinant genotype combinations, respectively. This is the first attempt on QTL discovery associated with PBND resistance in peanut. Superior RILs identified in the study can be recycled or released as variety following further evaluations. [ABSTRACT FROM AUTHOR]

Groundnut is an important food and oil crop in the semiarid tropics, contributing to household food consumption and cash income. In Asia and Africa, yields are low attributed to various production constraints. This review paper highlights advances in genetics, genomics and breeding to improve the productivity of groundnut. Genetic studies concerning inheritance, genetic variability and heritability, combining ability and trait correlations have provided a better understanding of the crop's genetics to develop appropriate breeding strategies for target traits. Several improved lines and sources of variability have been identified or developed for various economically important traits through conventional breeding. Significant advances have also been made in groundnut genomics including genome sequencing, marker development and genetic and trait mapping. These advances have led to a better understanding of the groundnut genome, discovery of genes/variants for traits of interest and integration of marker‐assisted breeding for selected traits. The integration of genomic tools into the breeding process accompanied with increased precision of yield trialing and phenotyping will increase the efficiency and enhance the genetic gain for release of improved groundnut varieties. [ABSTRACT FROM AUTHOR]

Legumes are important components of sustainable agricultural production, food, nutrition and income systems of developing countries. In spite of their importance, legume crop production is challenged by a number of biotic (diseases and pests) and abiotic stresses (heat, frost, drought and salinity), edaphic factors (associated with soil nutrient deficits) and policy issues (where less emphasis is put on legumes compared to priority starchy staples). Significant research and development work have been done in the past decade on important grain legumes through collaborative bilateral and multilateral projects as well as the CGIAR Research Program on Grain Legumes (CRP‐GL). Through these initiatives, genomic resources and genomic tools such as draft genome sequence, resequencing data, large‐scale genomewide markers, dense genetic maps, quantitative trait loci (QTLs) and diagnostic markers have been developed for further use in multiple genetic and breeding applications. Also, these mega‐initiatives facilitated release of a number of new varieties and also dissemination of on‐the‐shelf varieties to the farmers. More efforts are needed to enhance genetic gains by reducing the time required in cultivar development through integration of genomics‐assisted breeding approaches and rapid generation advancement. [ABSTRACT FROM AUTHOR]

Rust and late leaf spot (LLS) resistance sources involving Arachis batizocoi, A. duranensis, A. cardenasii and A. sps Manfredi‐5 were identified from field evaluation of interspecific derivatives (IDs) of groundnut in a disease nursery for two seasons. Although the sources displayed low levels of resistance compared to currently cultivated lines, they contribute allele diversity in groundnut breeding that has so far relied on alleles contributed from A. cardenasii for disease resistance. Multiple disease‐resistant and agronomically superior IDs, ICGVs 11379, 10121, 10179, 05097, 02411 and 00248 involving A. batizocoi, A. duranensis and A. cardenasii can be used in breeding for groundnut improvement. Genetic variability for resistance to rust and LLS, yield and nutritional quality traits was influenced by genotype, environment and genotype × environment interaction effects in individual and pooled analyses. In case of FAD (fatty acid desaturase)‐mutant alleles that govern high oleic trait, allele mining of IDs (110) showed that frequency of mutation in ahFAD2B is rare, whereas of ahFAD2A is common. High oleic lines were not detected among the IDs. [ABSTRACT FROM AUTHOR]