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Peanut (Arachis hypogaea L.) is an important nutrient-rich food legume and valued for its good quality cooking oil. The fatty acid content is the major determinant of the quality of the edible oil. The oils containing higher monounsaturated fatty acid are preferred for improved shelf life and potential health benefits. Therefore, a high oleic/linoleic fatty acid ratio is the target trait in an advanced breeding program. The two mutant alleles, ahFAD2A (on linkage group a09) and ahFAD2B (on linkage group b09) control fatty acid composition for higher oleic/linoleic ratio in peanut. In the present study, marker-assisted backcrossing was employed for the introgression of two FAD2 mutant alleles from SunOleic95R into the chromosome of ICGV06100, a high oil content peanut breeding line. In the marker-assisted backcrossing-introgression lines, a 97% increase in oleic acid, and a 92% reduction in linoleic acid content was observed in comparison to the recurrent parent. Besides, the oleic/linoleic ratio was increased to 25 with respect to the recurrent parent, which was only 1.2. The most significant outcome was the stable expression of oil-content, oleic acid, linoleic acid, and palmitic acid in the marker-assisted backcrossing-introgression lines over the locations. No significant difference was observed between high oleic and normal oleic in peanuts for seedling traits except germination percentage. In addition, marker-assisted backcrossing-introgression lines exhibited higher yield and resistance to foliar fungal diseases, i.e., late leaf spot and rust. [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]

Background: Foliar diseases namely late leaf spot (LLS) and leaf rust (LR) reduce yield and deteriorate fodder quality in groundnut. Also the high oleic acid content has emerged as one of the most important traits for industries and consumers due to its increased shelf life and health benefits. Results: Genetic mapping combined with pooled sequencing approaches identified candidate resistance genes (LLSR1 and LLSR2 for LLS and LR1 for LR) for both foliar fungal diseases. The LLS-A02 locus housed LLSR1 gene for LLS resistance, while, LLS-A03 housed LLSR2 and LR1 genes for LLS and LR resistance, respectively. A total of 49 KASPs markers were developed from the genomic regions of important disease resistance genes, such as NBS-LRR, purple acid phosphatase, pentatricopeptide repeat-containing protein, and serine/threonine-protein phosphatase. Among the 49 KASP markers, 41 KASPs were validated successfully on a validation panel of contrasting germplasm and breeding lines. Of the 41 validated KASPs, 39 KASPs were designed for rust and LLS resistance, while two KASPs were developed using fatty acid desaturase (FAD) genes to control high oleic acid levels. These validated KASP markers have been extensively used by various groundnut breeding programs across the world which led to development of thousands of advanced breeding lines and few of them also released for commercial cultivation. Conclusion: In this study, high-throughput and cost-effective KASP assays were developed, validated and successfully deployed to improve the resistance against foliar fungal diseases and oleic acid in groundnut. So far deployment of allele-specific and KASP diagnostic markers facilitated development and release of two rust- and LLS-resistant varieties and five high-oleic acid groundnut varieties in India. These validated markers provide opportunities for routine deployment in groundnut breeding programs. [ABSTRACT FROM AUTHOR]

Background: Foliar diseases namely late leaf spot (LLS) and leaf rust (LR) reduce yield and deteriorate fodder quality in groundnut. Also the high oleic acid content has emerged as one of the most important traits for industries and consumers due to its increased shelf life and health benefits. Results: Genetic mapping combined with pooled sequencing approaches identified candidate resistance genes (LLSR1 and LLSR2 for LLS and LR1 for LR) for both foliar fungal diseases. The LLS-A02 locus housed LLSR1 gene for LLS resistance, while, LLS-A03 housed LLSR2 and LR1 genes for LLS and LR resistance, respectively. A total of 49 KASPs markers were developed from the genomic regions of important disease resistance genes, such as NBS-LRR, purple acid phosphatase, pentatricopeptide repeat-containing protein, and serine/threonine-protein phosphatase. Among the 49 KASP markers, 41 KASPs were validated successfully on a validation panel of contrasting germplasm and breeding lines. Of the 41 validated KASPs, 39 KASPs were designed for rust and LLS resistance, while two KASPs were developed using fatty acid desaturase (FAD) genes to control high oleic acid levels. These validated KASP markers have been extensively used by various groundnut breeding programs across the world which led to development of thousands of advanced breeding lines and few of them also released for commercial cultivation. Conclusion: In this study, high-throughput and cost-effective KASP assays were developed, validated and successfully deployed to improve the resistance against foliar fungal diseases and oleic acid in groundnut. So far deployment of allele-specific and KASP diagnostic markers facilitated development and release of two rust- and LLS-resistant varieties and five high-oleic acid groundnut varieties in India. These validated markers provide opportunities for routine deployment in groundnut breeding programs. [ABSTRACT FROM AUTHOR]

Background: Foliar diseases namely late leaf spot (LLS) and leaf rust (LR) reduce yield and deteriorate fodder quality in groundnut. Also the high oleic acid content has emerged as one of the most important traits for industries and consumers due to its increased shelf life and health benefits. Results: Genetic mapping combined with pooled sequencing approaches identified candidate resistance genes (LLSR1 and LLSR2 for LLS and LR1 for LR) for both foliar fungal diseases. The LLS-A02 locus housed LLSR1 gene for LLS resistance, while, LLS-A03 housed LLSR2 and LR1 genes for LLS and LR resistance, respectively. A total of 49 KASPs markers were developed from the genomic regions of important disease resistance genes, such as NBS-LRR, purple acid phosphatase, pentatricopeptide repeat-containing protein, and serine/threonine-protein phosphatase. Among the 49 KASP markers, 41 KASPs were validated successfully on a validation panel of contrasting germplasm and breeding lines. Of the 41 validated KASPs, 39 KASPs were designed for rust and LLS resistance, while two KASPs were developed using fatty acid desaturase (FAD) genes to control high oleic acid levels. These validated KASP markers have been extensively used by various groundnut breeding programs across the world which led to development of thousands of advanced breeding lines and few of them also released for commercial cultivation. Conclusion: In this study, high-throughput and cost-effective KASP assays were developed, validated and successfully deployed to improve the resistance against foliar fungal diseases and oleic acid in groundnut. So far deployment of allele-specific and KASP diagnostic markers facilitated development and release of two rust- and LLS-resistant varieties and five high-oleic acid groundnut varieties in India. These validated markers provide opportunities for routine deployment in groundnut breeding programs. [ABSTRACT FROM AUTHOR]

Sesame (Sesamum indicum L.) is a summer crop and its production is threatened by drought stress (WS) due to increased aridity and higher temperature worldwide. Breeding sesame accessions that are more tolerant to WS is therefore highly important for sustainable seed production. Here, 21 accessions representing 12 sesame‐growing countries were evaluated with yield and quality traits under two different water‐regime treatments as non‐stressed (NS) and WS. The combined analysis of variance revealed that there was a significant variation among the accessions for all agronomic traits. We also found that the effects of treatment and genotype were significant for the quality traits of oil content, stearic acid, oleic acid, linoleic acid, and linolenic acid. The t‐test of significance for mean values indicated that there were significant differences between the treatments for plant height, number of branches, number of capsules, and seed yield. The highest yield was found in PI 170735 with the value of 25.6 g/plant in the treatment of WS. The higher values were observed for oil content in NS treatment, the highest amount of oil content was recorded as 53.9% for PI 207664. In addition, higher grand mean was observed for oleic acid under WS treatment. Principal component analysis using the five agronomic traits indicated that 76.60% and 71.18% variability accounted for the first two principal components (PCs) with eigen values ≥ 1 in WS and NS treatments, respectively. The diverse accessions characterized with agro‐quality traits can be used in further improvement programs to develop new drought‐tolerant cultivars. Core Ideas: Drought is an important limitation of sesame crop productivity.Drought stress significantly reduces traits of number of capsule and seed yield.Water‐stress condition made oleic acid content high.PI 170735 was noted as drought tolerant accession with higher yield and stress tolerance index. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "High-throughput diagnostic markers for foliar fungal disease resistance and high oleic acid content in groundnut" published in BMC Plant Biology. The authors identified minor typographical errors in the original article and provided the corrected versions. The errors were related to the description of the composition of groundnut oil and the function of the fatty acid desaturase enzyme. The corrected article has been published to address these errors. The publisher, Springer Nature, remains neutral and does not take any position on jurisdictional claims or institutional affiliations. [Extracted from the article]

The yield loss in peanut due to peanut bud necrosis disease ranges from 30 to 80%. Quantitative trait loci (QTL) were mapped using 108 RILs from a cross between JL-24 × NRCGCS-85. Phenotyping of these RILs was performed at natural hotspot under field conditions in 2017 post-rainy and 2018 rainy seasons. Significant variations were observed among the RILs confirming polygenic control and additive type of gene action for the disease. After screening of 1980 SSR markers, 227 were found polymorphic between the parents. Out of them 49 polymorphic markers effectively amplified codominant amplicons between homozygotes (parent) and heterozygotes (F1s). Linkage maps with 49 markers showed eight linkages having 47 markers. Using inclusive composite interval mapping, two major QTLs, namely QTLPBND-01 and QTLPBND-02 for PBND resistance, were detected, explaining 12.38–16.88% of phenotypic variance. Besides, superior RILs, (JL 24 × NRCGCS 85)-26-13 and (JL 24 × NRCGCS 85)-10-12 were identified with 26% and 17% higher pod yield over JL 24 and resistant to PBND with less than 5% disease scoring. These two RILs also contains two freshly identified QTLs. Among three tightly linked markers, AHS0006 associated with QTLPBND-01 was found stable and to code for sialyl transferase-like protein 1 responsible for protein glycosylation and sialyl transferase activity. This is also the first report of stlp 1 gene associated with PBND resistance, which will help in accelerating the genomic breeding approaches for PBND resistance in peanut in the future. [ABSTRACT FROM AUTHOR]

Key message: Groundnut has entered now in post-genome era enriched with optimum genomic and genetic resources to facilitate faster trait dissection, gene discovery and accelerated genetic improvement for developing climate-smart varieties. Cultivated groundnut or peanut (Arachis hypogaea), an allopolyploid oilseed crop with a large and complex genome, is one of the most nutritious food. This crop is grown in more than 100 countries, and the low productivity has remained the biggest challenge in the semiarid tropics. Recently, the groundnut research community has witnessed fast progress and achieved several key milestones in genomics research including genome sequence assemblies of wild diploid progenitors, wild tetraploid and both the subspecies of cultivated tetraploids, resequencing of diverse germplasm lines, genome-wide transcriptome atlas and cost-effective high and low-density genotyping assays. These genomic resources have enabled high-resolution trait mapping by using germplasm diversity panels and multi-parent genetic populations leading to precise gene discovery and diagnostic marker development. Furthermore, development and deployment of diagnostic markers have facilitated screening early generation populations as well as marker-assisted backcrossing breeding leading to development and commercialization of some molecular breeding products in groundnut. Several new genomics applications/technologies such as genomic selection, speed breeding, mid-density genotyping assay and genome editing are in pipeline. The integration of these new technologies hold great promise for developing climate-smart, high yielding and more nutritious groundnut varieties in the post-genome era. [ABSTRACT FROM AUTHOR]