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interactions were found among the three factors, plant density, seed category and plant type,
for all measured fitness components (Table 2.2).
Effect of plant density on performances of plants from different seed categories For
trF1, increased density only delayed flowering of medium-seeded plants (F1,41=5.7, P=0.022)
and increased thousand seeds weight of small-seeded plants (F1,35=6.1, P=0.018) (F ig. 2.2).
Flowering d ate ( F1,39=5.9, P =0.02 f or l arge-seeded p lants; F 1,38=5.2, P =0.028 f or m edium;
F1,34=10.5, P =0.002 f or s mall) a nd bi omass ( F1,40=15.01, P =0.003 f or l arge-seeded p lants;
F1,38=4.3, P =0.045 f or medium; F 1,37=7.2, P =0.01 f or s mall) i n nt rF1 were s ignificantly
affected by plant density for all three seed categories. Seed number of small-seeded plants in
ntrF1 at low density was higher than at high density (F1,37=7.9, P=0.007), but there were no
differences between plant densities for large- and medium-seeded plants in ntrF1. Thousandseed
weight was not affected for all seed categories in ntrF1 (Fig. 2.2).
Large-, m edium- and s mall-seeded pl ants of m ustard pr oduced hi gher biomass a nd,
more s eeds (P0.05, Fig. 2.2).
Days t o f lowering, bi omass, s eed num ber and t housand-seed num ber of l arge- and
medium-seeded pl ants of G T w as not a ffected by pl ant de nsity ( P>0.05). Increased pl ant
density delayed flowering time (F1,36=25.1, P=0.000), decreased biomass (F1,36=6.7, P=0.014)
and seed number (F1,36=15.9, P=0.000) for small-seeded plants of GT (Fig. 2.2).
Performances o f d ifferent s eed ca tegories Small-seeded pl ants of t rF1 revealed no
difference in fitness components compared to medium- and large-seeded plants in both high
and l ow de nsity popul ations ( Fig. 2.2). T he t hree s eed c ategories of ntrF1 pr oduced no
different s eed num ber a nd bi omass a t bot h hi gh a nd l ow de nsity l evels, but s mall-seeded
plants delayed flowering at high density and produced lower thousand-seed weight than largeseeded
pl ants a t l ow d ensity ( Fig. 2.2). S mall-seeded pl ants of wild m ustard pr oduced no
different biomass, seed number and thousand-seed weight compared with the other two seed
categories, and they flowered later at both high and low density (Fig. 2.2).
The three seed categories of GT performed differently at the two densities (Fig. 2.2). At
high density, small-seeded plants flowering later and produced less biomass and seeds than
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