Hybridization and Self-compatibility in Celtis: AFLP Analysis of Controlled Crosses

Artificial cross-pollinations were carried out among seven species of Celtis L. (C. bungeana Blume, C. koraiensis Nakai, C. laevigata Willd., C. occidentalis L., C. reticulata Torr., C. sinensis Pers., and C. tenuifolia Nutt.) to test the potential for interspecific hybridization in Celtis breeding. AFLP profiles were used to assess the ancestry of progeny. Hybrids formed very rarely among these seven species of Celtis: only two interspecific hybrids were obtained. Self-pollination occurred occasionally in non-emasculated trees. AFLP analysis yielded false paternal markers at a very low frequency, likely due to DNA methylation differences. Plants with unexpected paternal markers were confidently distinguished from hybrids by calculating the probability of obtaining the observed number of paternal markers by chance. The study clearly demonstrated the importance of using large numbers of markers.

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BROADENING THE GENETIC BASE OF CASSAVA, Manihot esculenta Crantz, BY INTERSPECIFIC HYBRIDIZATION

Canadian Journal of Plant Science ◽

10.4141/cjps89-129 ◽

1989 ◽

Vol 69 (3) ◽

pp. 1071-1073 ◽

Cited By ~ 20

Author(s):

NAGIB M. A. NASSAR

Keyword(s):

Interspecific Hybridization ◽

Manihot Esculenta ◽

Interspecific Hybrids ◽

Marker Genes ◽

Manihot Esculenta Crantz ◽

Genetic Base ◽

Controlled Crosses

Controlled crosses by vector insects resulted in the production of interspecific hybrids of cassava (Manihot esculenta Crantz) and Manihot species, while manual crosses failed. Marker genes for hairy stem, red disk, unribbed fruit, and foliaceous brackteoles proved efficient in recognizing interspecific hybridization between Manihot species and cassava.Key words: Wild cassava, Manihot neusana, Manihot anomala, interspecific hybridization, marker genes

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Obtaining interspecific hybrids, and molecular analysis by microsatellite markers in grapevine

Pesquisa Agropecuária Brasileira ◽

10.1590/s0100-204x2011001100009 ◽

2011 ◽

Vol 46 (11) ◽

pp. 1480-1488 ◽

Cited By ~ 9

Author(s):

Mariane Ruzza Schuck ◽

Luiz Antonio Biasi ◽

Ada Michele Mariano ◽

Bernardo Lipski ◽

Summaira Riaz ◽

...

Keyword(s):

Microsatellite Markers ◽

Interspecific Hybridization ◽

Molecular Analysis ◽

Interspecific Hybrids ◽

Female Parent ◽

F1 Hybrids ◽

Reciprocal Crosses ◽

Self Pollination ◽

Vitis Labruscana ◽

Muscadinia Rotundifolia

The objective of this work was to assess the potential of interspecific hybridization of Vitis labruscana and Muscadinia rotundifolia by using artificial cross-pollinations. Microsatellite markers were used to confirm interspecific hybridizations and the identity of the parental genotypes. In crosses in which M. rotundifolia was used as the female parent, no true hybrids were obtained. In the reciprocal crosses, 114 seedlings were identified as true V. labruscana x M. rotundifolia hybrids. Self pollination occurred in direct and in reciprocal crosses. The crossings between 'Bordo' x 'Carlos', 'Magnolia', 'Regale' and' Roanoke', and between' Isabel' x 'Bountiful', 'Carlos', 'Magnolia', 'Regale' and 'Roanoke' were confirmed. The 15 markers evaluated showed that two M. rotundifolia parental genotypes had the same fingerprint profile, indicating a like lyplanting error. The success of hybridization depends mainly on the species and on the cultivar used as the female parent. Microsatellite markers are efficient to confirm the paternity of interspecific F1 hybrids and to determine the correct identity of M. rotundifolia cultivars.

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The Attenuation of Very Low Frequency Brain Oscillations in Transitions from a Rest State to Active Attention

Journal of Psychophysiology ◽

10.1027/0269-8803.23.4.191 ◽

2009 ◽

Vol 23 (4) ◽

pp. 191-198 ◽

Cited By ~ 26

Author(s):

Suzannah K. Helps ◽

Samantha J. Broyd ◽

Christopher J. James ◽

Anke Karl ◽

Edmund J. S. Sonuga-Barke

Keyword(s):

Brain Activity ◽

Sampling Rate ◽

Low Frequency ◽

Future Research ◽

Adhd Symptoms ◽

Default Mode ◽

Very Low Frequency ◽

Wide Range ◽

Interference Hypothesis ◽

Mode Interference

Background: The default mode interference hypothesis ( Sonuga-Barke & Castellanos, 2007 ) predicts (1) the attenuation of very low frequency oscillations (VLFO; e.g., .05 Hz) in brain activity within the default mode network during the transition from rest to task, and (2) that failures to attenuate in this way will lead to an increased likelihood of periodic attention lapses that are synchronized to the VLFO pattern. Here, we tested these predictions using DC-EEG recordings within and outside of a previously identified network of electrode locations hypothesized to reflect DMN activity (i.e., S3 network; Helps et al., 2008 ). Method: 24 young adults (mean age 22.3 years; 8 male), sampled to include a wide range of ADHD symptoms, took part in a study of rest to task transitions. Two conditions were compared: 5 min of rest (eyes open) and a 10-min simple 2-choice RT task with a relatively high sampling rate (ISI 1 s). DC-EEG was recorded during both conditions, and the low-frequency spectrum was decomposed and measures of the power within specific bands extracted. Results: Shift from rest to task led to an attenuation of VLFO activity within the S3 network which was inversely associated with ADHD symptoms. RT during task also showed a VLFO signature. During task there was a small but significant degree of synchronization between EEG and RT in the VLFO band. Attenuators showed a lower degree of synchrony than nonattenuators. Discussion: The results provide some initial EEG-based support for the default mode interference hypothesis and suggest that failure to attenuate VLFO in the S3 network is associated with higher synchrony between low-frequency brain activity and RT fluctuations during a simple RT task. Although significant, the effects were small and future research should employ tasks with a higher sampling rate to increase the possibility of extracting robust and stable signals.

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