seed dormancy

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Cistus laurifolius L. subsp. laurifolius (Cistaceae) in Italy: preliminary data on population structure, reproductive fitness and seed dormancy. 1. The Italian ...
Cistus laurifolius L. subsp. laurifolius (Cistaceae) in Italy: preliminary data on population structure, reproductive fitness and seed dormancy Marco D’Antraccoli, Francesco Roma-Marzio, Giovanni Astuti, Lorenzo Peruzzi INTRODUCTION Currently Cistus laurifolius L. subsp. laurifolius occurs in Italy only in one site (red point in the map), in Tuscany. This species is one of the most interesting Italian woody taxa from a phytogeographic and a conservation points of view IUCN assessment at Italian level: VULNERABLE (VU; D2)

AIMS OF THE STUDY: • To evaluate the size and demography of the Italian population • To investigate the reproductive biology for each subpopulations and for different density classes • To study seed dormancy through heat shock and scarification effects on Water uptake (WUP) and final germination (FGP) percentages

Cistus laurifolius L. subsp. atlanticus Cistus laurifolius L. subsp. laurifolius

POPULATION TRAITS *

A significant higher number of seeds per fruit in the largest subpopulation (i.e. Fornellaccio)

N

Fornellaccio CAI5 Altitude: 615 m a.s.l. Total individuals: 351 Area: 6680 m²

Altitude: 670 m a.s.l. Total individuals: 9471 Area: 77215 m²

Masseto

Fontassenzio

Altitude: 430 m a.s.l. Total individuals: 47 Area: 150 m²

Altitude: 730 m a.s.l. Total individuals: 92 Area: 2100 m²

* p < 0.01

Class I juvenile plants (≤ 6 leaves) Class II intermediate stage (> 6 leaves, without flowers) Class III adult plants (> 6 leaves, with flowers)

Campo sportivo Altitude: 490 m a.s.l. Total individuals: 1 Area: N.A.

500 m

PLANT DENSITY EFFECTS

SEED DORMANCY

* ≈ 20 m WUP = 30.4 ± 18.0 High-density n>5

Medium-density 2≤n≤3

FGP = 16.7 t50 = 23.8

WUP = 36.0 + 5.2

FGP = 38.0 t50 = 16.0

Low-density n