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Summary Though several genes governing various major traits have been reported in rice, their superior haplotype combinations for developing ideal variety remains elusive. In this study, haplotype analysis of 120 previously functionally characterized genes, influencing grain yield (87 genes) and grain quality (33 genes) revealed significant variations in the 3K rice genome ( RG ) panel. For selected genes, meta‐expression analysis using already available datasets along with co‐expression network provided insights at systems level. Also, we conducted candidate gene based association study for the 120 genes and identified 21 strongly associated genes governing 10‐grain yield and quality traits. We report superior haplotypes upon phenotyping the subset of 3K RG panel, SD 1 ‐H8 with haplotype frequency ( HF ) of 30.13% in 3K RG panel, MOC 1 ‐H9 ( HF : 23.08%), IPA 1 ‐H14 ( HF : 6.64%), DEP 3 ‐H2 ( HF : 5.59%), DEP 1 ‐H2 ( HF : 37.53%), SP 1 ‐H3 ( HF : 5.05%), LAX 1 ‐H5 ( HF : 1.56%), LP ‐H13 (3.64%), OSH 1 ‐H4 (5.52%), PHD 1 ‐H14 ( HF : 15.21%), AGO 7 ‐H15 ( HF : 3.33%), ROC 5 ‐H2 (31.42%), RSR 1 ‐H8 ( HF : 4.20%) and Os NAS 3 ‐H2 ( HF : 1.00%). For heading date, Ghd7 ‐H8 ( HF : 3.08%), TOB 1 ‐H10 ( HF : 4.60%) flowered early, Ghd7 ‐H14 ( HF : 42.60%), TRX 1 ‐H9 ( HF : 27.97%), Os VIL 3 ‐H14 ( HF : 1.72%) for medium duration flowering, while Ghd7 ‐H6 ( HF : 1.65%), SNB ‐H9 ( HF : 9.35%) were late flowering. GS 5 ‐H4 ( HF : 65.84%) attributed slender, GS 5 ‐H5 ( HF : 29.00%), GW 2 ‐H2 ( HF : 4.13%) were medium slender and GS 5 ‐H9 ( HF : 2.15%) for...

Increases in rice productivity are significantly hampered because of the increase in the occurrence of abiotic stresses, including drought, salinity, and submergence. Developing a rice variety with inherent tolerance against these major abiotic stresses will help achieve a sustained increase in rice production under unfavorable conditions. The present study was conducted to develop abiotic stress-tolerant rice genotypes in the genetic background of the popular rice variety Improved White Ponni (IWP) by introgressing major effect quantitative trait loci (QTLs) conferring tolerance against drought (qDTY 1.1 , qDTY 2.1), salinity (Saltol), and submergence (Sub1) through a marker assisted backcross breeding approach. Genotyping of early generation backcrossed inbred lines (BILs) resulted in the identification of three progenies, 3-11-9-2, 3-11-11-1, and 3-11-11-2, possessing all four target QTLs and maximum recovery of the recurrent parent genome (88.46%). BILs exhibited consistent agronomic and grain quality characters compared to those of IWP and enhanced performance against dehydration, salinity, and submergence stress compared with the recurrent parent IWP. BILs exhibited enhanced tolerance against salinity during germination and increased shoot length, root length, and vigor index compared to those of IWP. All three BILs exhibited reduced symptoms of injury because of salinity (NaCl) and dehydration (PEG) than did IWP. At 12 days of submergence stress, BILs exhibited enhanced survival and greater recovery, whereas IWP failed completely. BILs were found to exhibit on par grain and cooking quality characteristics with their parents. Results of this study clearly demonstrated the effects of the target QTLs in reducing damage caused by drought, salinity, and submergence and lead to the development of a triple stress tolerant version of IWP.

There has been a growing interest in the design of environmentally affable and biocompatible nanoparticles among scientists to find novel and safe biomaterials. Panax ginseng Meyer berries have unique phytochemical profile and exhibit beneficial pharmacological activities such as antihyperglycemic, antiobesity, antiaging, and antioxidant properties. A comprehensive study of the biologically active compounds in ginseng berry extract (GBE) and the ability of ginseng berry (GB) as novel material for the biosynthesis of gold nanoparticles (GBAuNPs) and silver nanoparticles (GBAgNPs) was conducted. In addition, the effects of GBAuNPs and GBAgNPs on skin cell lines for further potential biological applications are highlighted. GBAuNPs and GBAgNPs were synthesized using aqueous GBE as a reducing and capping agent. The synthesized nanoparticles were characterized for their size, morphology, and crystallinity. The nanoparticles were evaluated for antioxidant, anti-tyrosinase, antibacterial, and cytotoxicity activities and for morphological changes in human dermal fibroblast and murine melanoma skin cell lines. The phytochemicals contained in GBE effectively reduced and capped gold and silver ions to form GBAuNPs and GBAgNPs. The optimal synthesis conditions (ie, temperature and v/v % of GBE) and kinetics were investigated. Polysaccharides and phenolic compounds present in GBE were suggested to be responsible for stabilization and functionalization of nanoparticles. GBAuNPs and GBAgNPs showed increased scavenging activity against 2,2-diphenyl-1-picrylhydrazyl free radicals compared to GBE. GBAuNPs and GBAgNPs effectively inhibited mushroom tyrosinase, while GBAgNPs showed antibacterial activity against Escherichia coli and Staphylococcus aureus . In addition, GBAuNPs were nontoxic to human dermal fibroblast and murine melanoma cell lines, and GBAgNPs showed cytotoxic effect on murine melanoma cell lines. The current results evidently suggest that GBAgNPs can act as potential agents for antioxidant, anti-tyrosinase, and antibacterial activities. In addition, GBAuNPs can be further developed into mediators in drug delivery and as antioxidant, anti-tyrosinase, and protective skin agents in cosmetic products. Consequently, the study showed the advantages of using nanotechnology and green chemistry to enhance the natural properties of GBs.

Haplotype-based breeding, a recent promising breeding approach to develop tailor-made crop varieties, deals with identification of superior haplotypes and their deployment in breeding programmes. In this context, whole genome re-sequencing data of 292 genotypes from pigeonpea reference set were mined to identify the superior haplotypes for 10 droughtresponsive candidate genes. A total of 83, 132 and 60 haplotypes were identified in breeding lines, landraces and wild species, respectively. Candidate gene-based association analysis of these 10 genes on a subset of 137 accessions of the pigeonpea reference set revealed 23 strong marker-trait associations (MTAs) in five genes influencing seven drought-responsive component traits. Haplo-pheno analysis for the strongly associated genes resulted in the identification of most promising haplotypes for three genes regulating five component drought traits. The haplotype C. cajan_23080-H2 for plant weight (PW), fresh weight (FW) and turgid weight (TW), the haplotype C. cajan_30211-H6 for PW, FW, TW and dry weight (DW), the haplotype C. cajan_26230-H11 for FW and DW and the haplotype C. cajan_26230-H5 for relative water content (RWC) were identified as superior haplotypes under drought stress condition. Furthermore, 17 accessions containing superior haplotypes for three drought-responsive genes were identified. The identified superior haplotypes and the accessions carrying these superior haplotypes will be very useful for deploying haplotype-based breeding to develop nextgeneration tailor-made better drought-responsive pigeonpea cultivars.

Background: Unfavorable climatic changes have led to an increased threat of several biotic and abiotic stresses over the past few years. Looking at the massive damage caused by these stresses, we undertook a study to develop high yielding climate-resilient rice, using genes conferring resistance against blast (Pi9), bacterial leaf blight (BLB) (Xa4, xa5, xa13, Xa21), brown planthopper (BPH) (Bph3, Bph17), gall midge (GM) (Gm4, Gm8) and QTLs for drought tolerance (qDTY 1.1 and qDTY 3.1 ) through marker-assisted forward breeding (MAFB) approach. Result: Seven introgression lines (ILs) possessing a combination of seven to ten genes/QTLs for different biotic and abiotic stresses have been developed using marker-assisted selection (MAS) breeding method in the background of Swarna with drought QTLs. These ILs were superior to the respective recurrent parent in agronomic performance and also possess preferred grain quality with intermediate to high amylose content (AC) (23-26%). Out of these, three ILs viz., IL1 (Pi9+ Xa4+ xa5+ Xa21+ Bph17+ Gm8+ qDTY 1.1 + qDTY 3.1 ), IL6 (Pi9+ Xa4+ xa5+ Xa21+ Bph3+ Bph17+ Gm4+ Gm8+ qDTY 1.1 + qDTY 3.1 ) and IL7 (Pi9+ Xa4+ xa5+ Bph3+ Gm4+ qDTY 1.1 + qDTY 3.1 ) had shown resistance\tolerance for multiple biotic and abiotic stresses both in the field and glasshouse conditions. Overall, the ILs were high yielding under various stresses and importantly they also performed well in non-stress conditions without any yield penalty. Conclusion:The current study clearly illustrated the success of MAS in combining tolerance to multiple biotic and abiotic stresses while maintaining higher yield potential and preferred grain quality. Developed ILs with seven to ten genes in the current study showed superiority to recurrent parent Swarna+drought for multiple-biotic stresses (blast, BLB, BPH and GM) together with yield advantages of 1.0 t ha − 1 under drought condition, without adverse effect on grain quality traits under non-stress.

Micronutrient especially iron and zinc-enriched rice hold immense promise for sustainable and cost-effective solutions to overcome malnutrition. In this context, BC 2 F 5 population derived from cross between RP-Bio226 and Sampada was used to localize genomic region(s)/QTL(s) for grain Fe (iron) and Zn (zinc) content together with yield and yield-related traits. Genotyping of mapping population with 108 SSR markers resulted in a genetic map of 2317.5 cM with an average marker distance of 21.5 cM. Mean grain mineral content in the mapping population across the two seasons ranged from 10.5–17.5 ppm for Fe and 11.3–22.1 ppm for Zn. Based on the multi-season phenotypic data together with genotypic data, a total of two major QTLs for Fe (PVE upto 17.1%) and three for Zn (PVE upto 34.2%) were identified. Comparative analysis across the two seasons has revealed four consistent QTLs for Fe ( qFe 1.1 , qFe 1.2 , qFe 6.1 and qFe 6.2 ) and two QTL for Zn content ( qZn 1.1 and qZn 6.2 ). Additionally, based on the previous and current studies three meta-QTLs for grain Fe and two for grain Zn have been identified. In-silico analysis of the identified QTL regions revealed the presence of potential candidate gene(s) such as, OsPOT , OsZIP4 , OsFDR3 , OsIAA5 etc., that were previously reported to influence grain Fe and Zn content. The identified QTLs could be utilized in developing high yielding, Fe and Zn denser varieties by marker assisted selection (MAS).

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