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1.
An Acad Bras Cienc ; 86(3): 1497-505, 2014 Sep.
Article de Anglais | MEDLINE | ID: mdl-25211117

RÉSUMÉ

Taxus baccata is a native species to the Caspian forests and is considered as the identification of these forests by some resources. The aim of this study was to understand the ecological characteristics of T. baccata in order to find suitable areas for its plantation in the Pone Aram preserve of Golestan province. Therefore, Multi-Criteria Evaluation (MCE) methods based on Analytical Hierarchy Process (AHP) were used. In this process at first the needed and effective natural indexes were used as 10 parameters. Then the final map of suitable areas for T. baccata plantation were produced based on Bolian and MCE models. According to the results, in Bolian method about 6218 ha of the total area of the study site (30554 ha) were estimated as suitable and semi suitable and 24336 ha were estimated as unsuitable for MCE model showed that about 2482 ha of the whole 30554 ha area of the study site is adequate for T. baccata plantation and 6181 ha is not adequate for T. baccata plantation. Regarding the results of the MCE and Bolian methods it has been concluded that for dynamic ecological parameters in delineation of suitable areas for T. baccata plantation the MCE weighting is more appropriate than Bolian. Using the results of this investigation it is possible to adequate areas for the presence of T. baccata and to execute a plan in order to facilitate the plantation of T. baccata in northern forests of Iran (watershed 88).


Sujet(s)
Agriculture/méthodes , Systèmes d'information géographique , Taxus/croissance et développement , Iran , Modèles théoriques , Taxus/classification
2.
Evol Dev ; 9(5): 446-59, 2007.
Article de Anglais | MEDLINE | ID: mdl-17845516

RÉSUMÉ

The identity of genes causally implicated in the development and evolutionary origin of reproductive characters in gymnosperms is largely unknown. Working within the framework of plant evolutionary developmental biology, here we have cloned, sequenced, performed phylogenetic analyses upon and tested the expression patterns of LEAFY/FLORICAULA and NEEDLY orthologs in reproductive structures from selected species of the conifer genera Picea, Podocarpus, and Taxus. Contrary to expectations based on previous assessments, expression of LFY/FLO and NLY in cones of these taxa was found to occur simultaneously in a single reproductive axis, initially overlapping but later in mutually exclusive primordia and/or groups of developing cells in both female and male structures. These observations directly affect the status of the "mostly male theory" for the origin of the angiosperm flower. On the other hand, comparative spatiotemporal patterns of the expression of these genes suggest a complex genetic regulatory network of cone development, as well as a scheme of functional divergence for LFY/FLO with respect to NLY homologs in gymnosperms, both with clear heterochronic aspects. Results presented in this study contribute to the understanding of the molecular-genetic basis of morphological evolution in conifer cones, and may aid in establishing a foundation for gymnosperm-specific, testable evo-devo hypotheses.


Sujet(s)
Évolution biologique , Protéines végétales/métabolisme , Tracheobionta/métabolisme , Facteurs de transcription/métabolisme , Cycadopsida/classification , Cycadopsida/croissance et développement , Cycadopsida/métabolisme , Fonctions de vraisemblance , Phylogenèse , Picea/classification , Picea/croissance et développement , Picea/métabolisme , Protéines végétales/classification , Protéines végétales/génétique , ARN messager/métabolisme , Taxus/classification , Taxus/croissance et développement , Taxus/métabolisme , Tracheobionta/classification , Tracheobionta/croissance et développement , Facteurs de transcription/classification , Facteurs de transcription/génétique
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