4 research outputs found
Identification of QTLs for pod and kernel traits in cultivated peanut by bulked segregant analysis
Bulked segregant analysis was used to identify simple sequence repeat
(SSR) markers associated with pod and kernel traits in cultivated
peanut, to permit rapid selection of superior quality genotypes in the
breeding program. SSR markers linked to pod and kernel traits were
identified in two DNA pools (high and low), which were established
using selected F2:6 recombinant individuals resulting from a cultivated
cross between a runner (Tamrun OL01) and a Spanish (BSS 56) peanut. To
identify quantitative trait loci (QTLs) for pod and kernel-related
traits, parents were screened initially with 112 SSR primer pairs. The
survey revealed 8.9% polymorphism between parents. Of ten SSR primer
pairs distinguishing the parents, five (PM375, PM36, PM45, pPGPseq8D9,
and Ah-041) were associated with differences between bulks for seed
length, pod length, number of pods per plant, 100-seed weight,
maturity, or oil content. Association was confirmed by analysis of
segregation among 88 F2:6 individuals in the RIL population. Phenotypic
means associated with markers for three traits differed by more than
40%, indicating the presence of QTLs with major effects for number of
pods per plant, plant weight, and pod maturity. The SSR markers can be
used for marker assisted selection for quality and yield improvement in
peanut. To the best of our knowledge, this is the first report on the
identification of SSR markers linked to pod - and kernel- related
traits in cultivated peanut
Identification of QTLs for pod and kernel traits in cultivated peanut by bulked segregant analysis
Bulked segregant analysis was used to identify simple sequence repeat
(SSR) markers associated with pod and kernel traits in cultivated
peanut, to permit rapid selection of superior quality genotypes in the
breeding program. SSR markers linked to pod and kernel traits were
identified in two DNA pools (high and low), which were established
using selected F2:6 recombinant individuals resulting from a cultivated
cross between a runner (Tamrun OL01) and a Spanish (BSS 56) peanut. To
identify quantitative trait loci (QTLs) for pod and kernel-related
traits, parents were screened initially with 112 SSR primer pairs. The
survey revealed 8.9% polymorphism between parents. Of ten SSR primer
pairs distinguishing the parents, five (PM375, PM36, PM45, pPGPseq8D9,
and Ah-041) were associated with differences between bulks for seed
length, pod length, number of pods per plant, 100-seed weight,
maturity, or oil content. Association was confirmed by analysis of
segregation among 88 F2:6 individuals in the RIL population. Phenotypic
means associated with markers for three traits differed by more than
40%, indicating the presence of QTLs with major effects for number of
pods per plant, plant weight, and pod maturity. The SSR markers can be
used for marker assisted selection for quality and yield improvement in
peanut. To the best of our knowledge, this is the first report on the
identification of SSR markers linked to pod - and kernel- related
traits in cultivated peanut
Gamma-ray emission from the Sagittarius dwarf spheroidal galaxy due to millisecond pulsars
The Fermi bubbles are giant, γ-ray-emitting lobes emanating from the nucleus of the Milky Way discovered in ~1–100 GeV data collected by the Large Area Telescope on board the Fermi Gamma-Ray Space Telescope. Previous work has revealed substructure within the Fermi bubbles that has been interpreted as a signature of collimated outflows from the Galaxy’s supermassive black hole. Here we show via a spatial template analysis that much of the γ-ray emission associated with the brightest region of substructure—the so-called cocoon—is probably due to the Sagittarius dwarf spheroidal galaxy (dSph). This large Milky Way satellite is viewed through the Fermi bubbles from the position of the Solar System. As a tidally and ram-pressure stripped remnant, the Sagittarius dSph has no ongoing star formation, but we nevertheless demonstrate that the dwarf’s millisecond pulsar population can plausibly supply the γ-ray signal that our analysis associates with its stellar template. The measured spectrum is naturally explained by inverse Compton scattering of cosmic microwave background photons by high-energy electron–positron pairs injected by millisecond pulsars belonging to the Sagittarius dSph, combined with these objects’ magnetospheric emission. This finding plausibly suggests that millisecond pulsars produce significant γ-ray emission among old stellar populations, potentially confounding indirect dark-matter searches in regions such as the Galactic Centre, the Andromeda galaxy and other massive Milky Way dSphs
Gamma-ray emission from the Sagittarius dwarf spheroidal galaxy due to millisecond pulsars
The Fermi bubbles are giant, γ-ray-emitting lobes emanating from the nucleus of the Milky Way discovered in ~1–100 GeV data collected by the Large Area Telescope on board the Fermi Gamma-Ray Space Telescope. Previous work has revealed substructure within the Fermi bubbles that has been interpreted as a signature of collimated outflows from the Galaxy’s supermassive black hole. Here we show via a spatial template analysis that much of the γ-ray emission associated with the brightest region of substructure—the so-called cocoon—is probably due to the Sagittarius dwarf spheroidal galaxy (dSph). This large Milky Way satellite is viewed through the Fermi bubbles from the position of the Solar System. As a tidally and ram-pressure stripped remnant, the Sagittarius dSph has no ongoing star formation, but we nevertheless demonstrate that the dwarf’s millisecond pulsar population can plausibly supply the γ-ray signal that our analysis associates with its stellar template. The measured spectrum is naturally explained by inverse Compton scattering of cosmic microwave background photons by high-energy electron–positron pairs injected by millisecond pulsars belonging to the Sagittarius dSph, combined with these objects’ magnetospheric emission. This finding plausibly suggests that millisecond pulsars produce significant γ-ray emission among old stellar populations, potentially confounding indirect dark-matter searches in regions such as the Galactic Centre, the Andromeda galaxy and other massive Milky Way dSphs