Biología de la Conservación de Vella pseudocytisus subespecie ...

Abstract
142 aProxImacIón a la bIología reProductIva
Biología de la Conservación de Vella pseudocytisus subsp. paui
We performed a monitoring program for the natural populations of Vella pseudocytisus
subsp. paui, recording leave, flower and fruit production during three consecutive
years. We sampled individuals distributed across two known populations
(villel and villalba Baja) and two different habitats (disturbed and non disturbed). in
addition, we evaluated the breeding system and calculated the p/o ratio. Finally, we
recorded pollinators in both populations.
the average flower and fruit productivity is large enough. the reproductive success
does not seem a limiting factor for the plant, and productivity is around 4,000
flowers and 3,400 fruits per individual.
results indicate that productivity and growth are similar in both populations during
the three year period. nevertheless, we detected differences, albeit not particularly
significant, in productivity between habitats. thus, individuals located in field
verges and taluses seemed more productive than individuals growing in more natural
habitats.
vegetative grow time was limited to few months, peaking at rainfall and temperature
maxima in spring. the plant follows a facultative deciduous strategy resembling
some subtropical species, thus the rate of leave losses is adjusted by the summer
effect. Flowering is at early stage and short (two months). Breeding system results in
a combination system: facultative allogamous with prevalent out-crossing, although
this result needs caution because pollination tests are not complete. the p/o ratio is
one of the highest recorded in the Brassicaceae family, although the plant seems to be
insect pollinated by a wide spectrum of generalist insects.
Introducción
la biología reproductiva, considerando también la fenología, es una
faceta del ciclo biológico condicionada por una serie de factores comunes:
abióticos —disponibilidad de nutrientes, agua y luz— y bióticos —polinizadores,
agentes de dispersión, predadores y patógenos— (primack, 1987;
guitián et al., 1992; Woolhouse, 1992). esta dependencia es más acusada
en ambientes estacionales como los mediterráneos (mooney y Kammerow,
1981; arroyo, 1988; petanidou y potts, 2006), donde algunos de los
factores mencionados pueden ser limitantes, modulando la respuesta fenológica
y reproductiva de las formaciones vegetales.
la reproducción tiene profundas consecuencias genéticas y evolutivas,
en la tasa de endogamia, en la configuración de la estructura genética
de las poblaciones y en la eficacia del flujo génico (Wyatt, 1983; slatkin,
1985; Karron, 1991). puede condicionar también relaciones ecológicas tales
como la interacción planta-polinizador, la relación flores/frutos o la
capacidad colonizadora. no es de extrañar, por tanto, que la casuística
sistema reproductor-planta rara sea extensa (por ejemplo Weller, 1994) y