1,729 research outputs found
Seleção assistida com uso de marcador molecular para resistência a potyvírus em pimentão.
O objetivo deste trabalho foi determinar a presença do alelo Pvr4, que confere resistência contra o PepYMV (Pepper yellow mosaic virus), em genótipos de pimentão comunmente encontrados no mercado brasileiro, com uso de um marcador molecular codominante tipo CAPS. A resistência ao PepYMV, nos genótipos CM?334?INRA, Myr?29 e em genótipos derivados do híbrido comercial Mônica?R, foi detectada como associada à banda de 444 pb, ligada ao alelo de resistência Pvr4. As plantas resistentes homozigotas (pvr4/pvr4) mostraram uma banda de 444 pb, as suscetíveis (Pvr4+/Pvr4+) uma banda de 458 pb e as resistentes heterozigotas (Pvr4+/Pvr4) mostraram as duas bandas. No entanto, no acesso resistente CM?334?UFV, nos híbridos Magali?R e Martha?R, assim como em populações derivadas desse acesso e desses híbridos, a resistência ao PepYMV não esteve associada ao marcador CAPS. O acesso CM?334?UFV ('Criollo de Morelos?334', de Viçosa, MG) distinguiu-se do CM?334?INRA ('Criollo de Morelos?334', da França); embora ambos os acessos tenham sido resistentes ao PepYMV, apenas em CM?334?INRA foi encontrada a associação da resistência com a banda de 444 pb
Spraying deposits using different nozzles and application volumes for pest management of cotton at reproductive stage.
With the growing need for greater operational capacity, information about the effect of application volume and spray nozzles on the quality of pesticide application are essential to obtain greater efficiency in pest management in cotton crops. This study aimed to assess the effect of the spraying volume and nozzles on the deposition of spray solution on cotton crops at the reproductive stage. The treatments of the first experiment correspond to the 55, 67, 140 and 194 L ha-1 volumes obtained by variation of the displacement speed using the XR11004 flat fan nozzle. In the second assay the treatments corresponded to the applications of MGA9004 (hollow cone), XR11004 (flat fan), AIXR11004 (air induction flat fan) and CVIA04 (air induction hollow cone) nozzles with 120 L ha-1. An artificial brilliant blue food dye (FD&C 1) was used as a tracer (2.5 g L-1) to determine the deposited volumes on the leaves of the upper, middle and lower third of cotton plants. The results showed that increase in the application volume contributed to obtain the larger deposits in the upper third of the cotton crop during its reproductive phase, especially up to 140 L ha-1, but did not exhibit a significant increase of the deposition in the middle and lower thirds of the plants. The MGA9004, XR11004 and AIXR11004 nozzles provided the largest deposits in the three plant sectors. The flat fan nozzles resulted in greater uniformity of deposits in the upper and middle thirds of the plants
Estimation of deposit and spray distribution in hydro sensible paper and morning glory plants.
The present work aimed to quantify the effects of surfactants addition over deposition and distribution of sprayer suspension in natural and artificial targets associated with different nozzles in relation to application offset, by using different assessment methods
Estoque de carbono e nitrogênio em latossolo amarelo sob sistema integração lavoura-pecuária no cerrado do Piauí.
A função do solo no seqüestro de carbono (C) atmosférico pode ser influenciada pelas práticas de manejo agrícola, devido à influência sobre o conteúdo de C orgânico do solo. O presente estudo teve por objetivo avaliar alterações nos teores e nos estoques de C e nitrogênio (N) em Latossolo Amarelo sob sistema integração lavourapecuária no cerrado do Piauí
The Novel P.e89k Mutation In The Sry Gene Inhibits Dna Binding And Causes The 46,xy Disorder Of Sex Development.
Male sex determination in humans is controlled by the SRY gene, which encodes a transcriptional regulator containing a conserved high mobility group box domain (HMG-box) required for DNA binding. Mutations in the SRY HMG-box affect protein function, causing sex reversal phenotypes. In the present study, we describe a 19-year-old female presenting 46,XY karyotype with hypogonadism and primary amenorrhea that led to the diagnosis of 46,XY complete gonadal dysgenesis. The novel p.E89K missense mutation in the SRY HMG-box was identified as a de novo mutation. Electrophoretic mobility shift assays showed that p.E89K almost completely abolished SRY DNA-binding activity, suggesting that it is the cause of SRY function impairment. In addition, we report the occurrence of the p.G95R mutation in a 46,XY female with complete gonadal dysgenesis. According to the three-dimensional structure of the human SRY HMG-box, the substitution of the conserved glutamic acid residue by the basic lysine at position 89 introduces an extra positive charge adjacent to and between the positively charged residues R86 and K92, important for stabilizing the HMG-box helix 2 with DNA. Thus, we propose that an electrostatic repulsion caused by the proximity of these positive charges could destabilize the tip of helix 2, abrogating DNA interaction.44361-
Seletividade de herbicidas pós-emergentes para a cultura do Pinhão Manso.
bitstream/item/78646/1/Boletim-142-.pd
Photoelectric Emission from Interstellar Dust: Grain Charging and Gas Heating
We model the photoelectric emission from and charging of interstellar dust
and obtain photoelectric gas heating efficiencies as a function of grain size
and the relevant ambient conditions. Using realistic grain size distributions,
we evaluate the net gas heating rate for various interstellar environments, and
find less heating for dense regions characterized by R_V=5.5 than for diffuse
regions with R_V=3.1. We provide fitting functions which reproduce our
numerical results for photoelectric heating and recombination cooling for a
wide range of interstellar conditions. In a separate paper we will examine the
implications of these results for the thermal structure of the interstellar
medium. Finally, we investigate the potential importance of photoelectric
heating in H II regions, including the warm ionized medium. We find that
photoelectric heating could be comparable to or exceed heating due to
photoionization of H for high ratios of the radiation intensity to the gas
density. We also find that photoelectric heating by dust can account for the
observed variation of temperature with distance from the galactic midplane in
the warm ionized medium.Comment: 50 pages, including 18 figures; corrected title and abstract field
Sulfur, Chlorine, and Argon Abundances in Planetary Nebulae. IV: Synthesis and the Sulfur Anomaly
We have compiled a large sample of O, Ne, S, Cl, and Ar abundances which have
been determined for 85 galactic planetary nebulae in a consistent and
homogeneous manner using spectra extending from 3600-9600 Angstroms. Sulfur
abundances have been computed using the near IR lines of [S III] 9069,9532
along with [S III] temperatures. We find average values, expressed
logarithmically with a standard deviation, of log(S/O)=-1.91(+/-.24),
log(Cl/O)=-3.52(+/-.16), and log(Ar/O)=-2.29(+/-.18), numbers consistent with
previous studies of both planetary nebulae and H II regions. We also find a
strong correlation between [O III] and [S III] temperatures among planetary
nebulae. In analyzing abundances of Ne, S, Cl, and Ar with respect to O, we
find a tight correlation for Ne-O, and loose correlations for Cl-O and Ar-O.
All three trends appear to be colinear with observed correlations for H II
regions. S and O also show a correlation but there is a definite offset from
the behavior exhibited by H II regions and stars. We suggest that this S
anomaly is most easily explained by the existence of S^+3, whose abundance must
be inferred indirectly when only optical spectra are available, in amounts in
excess of what is predicted by model-derived ionization correction factors.
Finally for the disk PNe, abundances of O, Ne, S, Cl, and Ar all show gradients
when plotted against galactocentric distance. The slopes are statistically
indistinguishable from one another, a result which is consistent with the
notion that the cosmic abundances of these elements evolve in lockstep.Comment: 43 pages, including 11 figures. Accepted for publication in the
Astronomical Journal. See also astro-ph/0106213 for Northern sample results,
astro-ph/0109161 and astro-ph/0108336 for the data and abundance information
for the Southern sample, and astro-ph/020954
A era glyphosate.
A molécula de glyphosate. Manejo de plantas daninhas. Resistência das plantas daninhas
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