UNIVERSITE DE BOURGOGNE THÈSE Yongbo LIU - Université de ...

Effects of plant density Plant density significantly affected the performances of the plants:
increased de nsity d ecreased num ber of f lowers, bi omass, s eed num ber a nd w eight and
percentage of small seeds, and increased thousand seeds weight and the percentage of large
and medium seeds (Table 2.1, Fig. 2.1). Emergence rate, days to flowering and reproductive
allocation were not affected by plant density (Table 2.1).
Performances o f p lants f rom d ifferent s eed ca tegories Seed c ategory s ignificantly
affected the da ys to flowering, number of flowers, thousand-seed weight and percentage of
medium and small seeds (Table 2.1, Fig. 2.1). There were no differences among different seed
categories f or em ergence r ate, b iomass, s eed n umber, r eproductive al location, s eed w eight
and percentage of large seeds (Table 1, Fig. 2.1). Large-seeded plants flowered earlier than
small-seeded p lants a t a ll th e th ree d ensities ( Fig. 2.1). S mall-seeded pl ants pr oduced l ess
flowers a t l ow de nsity and m ore s mall s eeds a t low a nd m edium de nsity t han l arge-seeded
plants, but there was no difference at high d ensity. Thousand s eeds weight in small-seeded
plants was lower than that in large-seeded plants only at low density (Fig. 2.1).
There was no interaction between density and s eed category effects for all the fitness
components in this experiment (Table 2.1).
Multi-culture experiment
When considering all the conditions, plant density significantly affected the emergence rate,
days t o flowering, bi omass, s eed num ber a nd w eight, a nd pe rcentage of l arge a nd m edium
seeds, a nd di d not a ffect r eproductive a llocation, t housand-seed w eight and p ercentage o f
small seeds (Table 2.2). Seed category significantly affected the days to flowering, biomass,
seed number and weight, thousand seeds weight and percentage of small seeds, and it did not
affect the emergence rate, reproductive allocation and percentage of large and medium seeds
(Table 2.2).
There were no interactions between density and seed category for all fitness components
except of the reproductive allocation (Table 2.2). Days to flowering, seed weight, thousandseed
w eight a nd pe rcentage of l arge s eeds ha d i nteraction be tween de nsity and pl ant t ype.
Days t o f lowering, s eed num ber, r eproductive allocation a nd t housand s eeds w eight ha d
interaction be tween s eed c ategory and pl ant t ype, but i t could b e due t o di fferent
categorization o f t he d ifferent p lant t ypes ( i.e. s eed s ize cr iteria w ere d ifferent). N o
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