Melão Tupã: origem e melhoramento genético.

bitstream/CNPAT-2010/7912/1/Dc-055.pd

Evaluation under long-day conditions of 4x-2x progenies from crosses between potato cultivars and haploid Tuberosum-solanum chacoense hybrids.

Twelve 4x families (obtained from a sub-set of crosses between seven 4x-potato cultivars and three 2x haploid Tuberosum-Solanum chacoense hybrids) were evaluated at Hancock, Wisconsin (USA). The 4x-parents were elite cultivars selected for adaptation in three continents (Europe, South America, and North America). The 2x male clones were able to produce 2n-pollen grains by a mechanism akin to first-division restitution with crossover (FDR-CO). The estimation of the degree of heterosis for total tuber yield (TTY) was obtained by comparing the field performance of the progenies with their respective 2x and 4x parents. Haulm maturity (HM) and general tuber appearance (GTA) were also evaluated. For TTY, the 4x-2x families (as a group) outyielded both the 4x and 2x parental groups by 10.6% and 42.5%, respectively. In addition, 5 out of 12 famiIies outyielded their corresponding 4x-parents. These best five families outyielded the group of 4x-parents by 40.6%. A considerable variability was observed for HM but, in general, the families were later maturing than the 4x cultivars. The identification of 4x-2x families with GTA within the range of the 4x commercial cultivars was another important observation. An overall lack of parent-offspring correlation was detected indicating that performance of the parents per se cannot provide a reliable prediction about the performance of the families. Therefore, progeny testing would be an imperative step for selection of parental clones at both ploidy levels. Our study indicated that haploid Tuberosum-S. chacoense hybrids are able to generate heterotic 4x-2x families for TTY in combination with good GTA. These results reinforce the view that selection of superior clones for the Northern Hemisphere can be feasible using germplasm with -25% genomic contribution of this wild South American species

Titanium dioxide-based 64 degrees YX LiNbO3 surface acoustic wave hydrogen gas sensors

Amorphous titanium dioxide (TiO2) and gold (Au) doped TiO2-based surface acoustic wave (SAW) sensors have been investigated as hydrogen gas detectors. The nanocrystal-doped TiO2 films were synthesized through a sol-gel route, mixing a Ti-butoxide-based solution with diluted colloidal gold nanoparticles. The films were deposited via spin coating onto 64° YX LiNbO3 SAW transducers in a helium atmosphere. The SAW gas sensors were operated at various temperatures between 150 and 310°C. It was found that gold doping on TiO2 increased the device sensitivity and reduced the optimum operating temperature

Titanium dioxide based 64° YX LiNbO3 surface acoustic wave hydrogen gas sensors

Amorphous titanium dioxide (TiO2) and gold (Au) doped TiO2-based surface acoustic wave (SAW) sensors have been investigated as hydrogen gas detectors. The nanocrystal-doped TiO2 films were synthesized through a sol-gel route,mixing a Ti-butoxide-based solution with diluted colloidal gold nanoparticles. The films were deposited via spin coating onto 64\ub0 YX LiNbO3 SAWtransducers in a helium atmosphere. The SAW gas sensors were operated at various temperatures between 150 and 310 \ub0C. It was found that gold doping on TiO2 increased the device sensitivity and reduced the optimum operating temperature

Linking Direct and Indirect Data on Dispersal: Isolation by Slope in a Headwater Stream Salamander

There is growing recognition of the need to incorporate information on movement behavior in landscape-scale studies of dispersal. One way to do this is by using indirect indices of dispersal (e.g., genetic differentiation) to test predictions derived from direct data on movement behavior. Mark–recapture studies documented upstream-biased movement in the salamander Gyrinophilus porphyriticus (Plethodontidae). Based on this information, we hypothesized that gene flow in G. porphyriticus is affected by the slope of the stream. Specifically, because the energy required for upstream dispersal is positively related to slope, we predicted gene flow to be negatively related to change in elevation between sampling sites. Using amplified DNA fragment length polymorphisms among tissue samples from paired sites in nine streams in the Hubbard Brook Watershed, New Hampshire, USA, we found that genetic distances between downstream and upstream sites were positively related to change in elevation over standardized 1-km distances. This pattern of isolation by slope elucidates controls on population connectivity in stream networks and underscores the potential for specific behaviors to affect the genetic structure of species at the landscape scale. More broadly, our results show the value of combining direct data on movement behavior and indirect indices to assess patterns and consequences of dispersal in spatially complex ecosystems

Linking Direct and Indirect Data on Dispersal: Isolation by Slope in a Headwater Stream Salamander

There is growing recognition of the need to incorporate information on movement behavior in landscape-scale studies of dispersal. One way to do this is by using indirect indices of dispersal (e.g., genetic differentiation) to test predictions derived from direct data on movement behavior. Mark–recapture studies documented upstream-biased movement in the salamander Gyrinophilus porphyriticus (Plethodontidae). Based on this information, we hypothesized that gene flow in G. porphyriticus is affected by the slope of the stream. Specifically, because the energy required for upstream dispersal is positively related to slope, we predicted gene flow to be negatively related to change in elevation between sampling sites. Using amplified DNA fragment length polymorphisms among tissue samples from paired sites in nine streams in the Hubbard Brook Watershed, New Hampshire, USA, we found that genetic distances between downstream and upstream sites were positively related to change in elevation over standardized 1-km distances. This pattern of isolation by slope elucidates controls on population connectivity in stream networks and underscores the potential for specific behaviors to affect the genetic structure of species at the landscape scale. More broadly, our results show the value of combining direct data on movement behavior and indirect indices to assess patterns and consequences of dispersal in spatially complex ecosystems

Melhoramento genético do melão amarelo na Embrapa Agroindústria Tropical.

bitstream/CNPAT-2010/11919/1/bp-25.pd

Desenvolvimento de marcadores microssatelites (SSR) para melao (Cucumis melo).

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