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These were dish-bowl blossoms with more or less exposed nectar: shallow flowers
o f
Hypericum
(33.3% of the pollen loads),
Filipemiu/o
(33.3% of the pollen loads), as
well Apiaceae. Brassicaceae,
Potentilia
or dense flat inflorescences with “tube” effect er
g. Asteraceae - presented in 61.1% of the pollen loads, Dipsaceae (Table 2a). The pollen
grains from bell and especially flag or gullet flowers were poorly presented. This was not
surprising considering the plants flowering in the area (Table 2).
Gemtana
pollen
quantity varied within species and conspecific individuals bumblebees (Tables 7 and 8):
Bombus pratomm (n
= 13, mean = 76.6%, min - 4% max = 100%
Bombas pyrenaetts
(л = 4, mean - 90.7%, min = 65% max = 100%).
Fig. 2.
Bombus terrastuis
worker pollinating
Gentiana aspclepiadea.
Gentiana punctata
L,
The most effective though third most numerous visitors after the flies
Tricops
spp.
and ants were the bumblebees - 12,3% of all insects visiting the flowers of this gentian.
Nectar collectors were 60.5% of all bumblebees. Most numerous were workers and males
Bombus pratorum -
69.1% of all bumblebees (Table 1).
The high flower constancy of bumblebees workers observed in the Fields
correlated with high percentage of
Gentiana-tvpe
pollen found in their pollen baskets
(mean = 75,8%, min = 3% max = 100%. Table 7). Their “minors” were 0 - 7 plant spe
cies (Table 8). These plants were more or less abundant in the area (Tables 3, 3a). These
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Электронная Научная СельскоХозяйственная Библиотека