Molecular diversity and association of simple sequence repeat markers with kernel mass in cultivated groundnut (Arachis hypogaea L.)

Abstract Groundnut yield can be further enhanced by improving pod and kernel size vis-a-vis mass. Marker assisted breeding will be an ideal option for directed improvement of hundred kernel mass. A study was undertaken to detect molecular diversity using 35 SSRs in 12 mutant genotypes, developed through chemical mutagenesis, from an interspecific large kernel size pre-breeding line and to identify markers associated with kernel mass. SSRs yielded an average of 3.57 polymorphic bands per primer. Average polymorphism and PIC were 64.95% and 0.62, respectively. Cluster analysis revealed two main clusters separated at 61% Jaccard's similarity coefficient. Vast of the genotypes were grouped into single cluster, confirming common pedigree of these genotypes. AMOVA among 12 mutant genotypes and their parent detected 15% of total variation associated with kernel mass. K-W ANOVA detected significant association of five SSRs with kernel mass. Among these associated primers, TC3A12 and TC9H09 accounted for 28% and 12% of phenotypic variation due to kernel mass and were associated with major QTLs. Out of these two associated primer, TC3A12 differentiated genotypes with higher kernel mass from genotypes with lower kernel mass by amplifying a band of approximately of 450bp. Thus association of TC3A12 primer with a major QTL of kernel mass was further validated in genotypes with diverse background. The TC3A12 primer discriminated genotypes with higher kernel mass from genotype with lower kernel mass by amplifying the band of 400bp among genotypes with higher kernel mass

Does improved oleic acid content due to marker-assisted introgression of ahFAD2 mutant alleles in peanuts alter its mineral and vitamin composition?

Peanuts (Arachis hypogaea L.) with high oleic acid content have extended shelf life and several health benefits. Oleic, linoleic, and palmitic acid contents in peanuts are regulated by ahFAD2A and ahFAD2B mutant alleles. In the present study, ahFAD2A and ahFAD2B mutant alleles from SunOleic 95R were introgressed into two popular peanut cultivars, GG-7 and TKG19A, followed by markers-assisted selection (MAS) and backcrossing (MABC). A total of 22 MAS and three MABC derived lines were developed with increased oleic acid (78–80%) compared to those of GG 7 (40%) and TKG 19A (50%). Peanut kernel mineral and vitamin composition remained unchanged, while potassium content was altered in high oleic ingression lines. Two introgression lines, HOMS Nos. 37 and 113 had over 10% higher pooled pod yield than respective best check varieties. More than 70% recurrent parent genome recovery was observed in HOMS-37 and HOMS-113 through recombination breeding. However, the absence of recombination in the vicinity of the target locus resulted in its precise introgression along with ample background genome recovery. Selected introgression lines could be released for commercial cultivation based on potential pod yield and oleic acid content

Not Available

Not AvailableGroundnut yield can be further enhanced by improving pod and kernel size vis-a-vis mass. Marker assisted breeding will be an ideal option for directed improvement of hundred kernel mass. A study was undertaken to detect molecular diversity using 35 SSRs in 12 mutant genotypes, developed through chemical mutagenesis, from an interspecific large kernel size pre-breeding line and to identify markers associated with kernel mass. SSRs yielded an average of 3.57 polymorphic bands per primer. Average polymorphism and PIC were 64.95% and 0.62, respectively. Cluster analysis revealed two main clusters separated at 61% Jaccard’s similarity coefficient. Vast of the genotypes were grouped into single cluster, confirming common pedigree of these enotypes. AMOVA among 12 mutant genotypes and their parent detected 15% of total variation associated with kernel mass. K-W ANOVA detected significant association of five SSRs with kernel mass. Among these associated primers, TC3A12 and TC9H09 accounted for 28% and 12% of phenotypic variation due to kernel mass and were associated with major QTLs. Out of these two associated primer, TC3A12 differentiated genotypes with higher kernel mass from genotypes with lower kernel mass by amplifying a band of approximately of 450bp. Thus association of TC3A12 primer with a major QTL of kernel mass was further validated in genotypes with diverse background. The TC3A12 primer discriminated genotypes with higher kernel mass from genotype with lower kernel mass by amplifying the band of 400bp among genotypes with higher kernel mass.Not Availabl

Graphene induced porphyrin nano-aggregates for efficient electron transfer and photocurrent generation

Significant research attention has been given to graphene–porphyrin hybrid materials for light harvesting. In this report, we demonstrate the influence of graphene surface and aging time on the formation of porphyrin [5-(4-hydroxyphenyl)-10,15,20-triphenyl porphyrin (4-HPTP)] aggregates. The large sp2 conjugated network of reduced graphene oxide (RGO) may facilitate strong π–π stacking interactions that influence the aggregation of 4-HPTP. The morphologies of these assembled structures are characterized by field emission scanning electron microscopy (FE-SEM). Steady state and time resolved spectroscopic studies reveal that the formation of J-type aggregation of 4-HPTP on an RGO surface is higher than on a graphene oxide (GO) surface. In situ growth of porphyrin nanoassemblies on an RGO surface improves the electronic interaction by shortening the interfacial distance between graphene and porphyrin. It is evident that the electron transfer process is enhanced in the presence of RGO upon the photoexcitation of porphyrin nanoassemblies which eventually generate a photocurrent. These graphene decorated porphyrin nanoassemblies are promising materials for the development of new generation optoelectronic devices

A ternary system of quantum dot – Porphyrin – Semiconducting organic nanoparticles for light harvesting

Inorganic–organic semiconductor hybrid nanostructures remain a frontier area of research to design optoelectronic, photovoltaic and light harvesting devices because of efficient energy or charge transfer process. Here, we have designed a system where inorganic semiconducting nanocrystals (Cd0.52Zn0.48S) are encapsulated into semiconducting organic poly (9-vinylcarbazole) [PVK] nanoparticles with 5-(4-aminophenyl)-10,15,20-triphenyl-21,23H-porphyrin (APTPP) molecule. Steady state and time resolved spectroscopic study reveal the efficient energy transfer from host PVK nanoparticle to QD and prophyrin molecule which is found to be cascade energy transfer. The energy transfer enhances from 68% to 86% by incorporating porphyrin molecule into QD doped PVK nanoparticles. This high efficiency of cascade energy transfer opens further prospects to design new porphyrin and quantum dot based functional polymer nanoparticles for the application in efficient light harvesting system and other photodriven devices

Photon harvesting in sunscreen-based functional nanoparticles

The ultraviolet light component in the solar spectrum is known to cause several harmful effects, such as allergy, skin ageing, and skin cancer. Thus, current research attention has been paid to the design and fundamental understanding of sunscreen-based materials. One of the most abundantly used sunscreen molecules is Avobenzone (AB), which exhibits two tautomers. Here, we highlight the preparation of spherically shaped nanoparticles from the sunscreen molecule AB as well as from sunscreen-molecule-encapsulated polymer nanoparticles in aqueous media and study their fundamental photophysical properties by steady-state and time-resolved spectroscopy. Steady-state studies confirm that the AB molecule is in the keto and enol forms in tetrahydrofuran, whereas the enol form is stable in the case of both AB nanoparticles and AB-encapsulated poly(methyl methacrylate) (PMMA) nanoparticles. Thus, the keto–enol transformation of AB molecules is restricted to a nanoenvironment. An enhancement of photostability in both the nanoparticle and PMMA-encapsulated forms under UV light irradiation is observed. The efficient excited energy transfer (60 %) from AB to porphyrin molecules opens up further prospects in potential applications as light-harvesting systems

Graphene–Porphyrin Nanorod Composites for Solar Light Harvesting

Well-defined organic nanostructures of porphyrin are promising candidates toward photocatalysis, photovoltaics, and electronics applications where a photoinduced electron transfer process occurs. On the other hand, reduced graphene oxides (RGO) have attracted much attention in light energy conversion owing to their efficient charge separation property. In this respect, we have demonstrated a composite of a one-dimensional (1D) nanostructure of 5, 10, 15, and 20-tetrakis (4-carboxyphenyl) porphyrin (TCPP) and RGO for enhancing photoinduced charge separation. The composite was characterized by scanning electron microscopy (SEM), UV–visible spectroscopy, fluorescence spectroscopy, time-correlated single photon counting (TCSPC), and femtosecond fluorescence upconversion spectroscopy. It is noted that a very fast decay of TCPP NR was observed in the TCPP NR–RGO composite due to the electron transfer process, and the electron transfer rate is found to be 10.0 × 10^–4 ps^–1 for the TCPP NR–RGO system. An increment (1.9 fold) of photocurrent of this composite system under visible light illumination is obtained due to electron transfer from TCPP NR to RGO. This new class of porphyrin-based composite structures opens up new possibilities in solar energy conversion and photocatalytic, photovoltaic, and other new emerging applications

Not Available

Not AvailableRust 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.Not Availabl