SEARCH
0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Prev | Current Page 471 | Next

Darwin, Charles, 1809-1882

"Effects of Cross and Self Fertilisation in the Vegetable Kingdom"

I examined many flowers on both plants,
and found the stigmas spontaneously covered with pollen; but they
produced not a single seed. These plants were afterwards left uncovered
in the same house where many other Cinerarias were in flower; and the
flowers were frequently visited by bees. They then produced plenty of
seed, but one of the two plants less than the other, as this species
shows some tendency to be dioecious.
The trial was repeated on another variety with white petals tipped with
red. Many stigmas on two corymbs were covered with pollen from the
foregoing purple variety, and these produced eleven and twenty-two
seeds, which germinated well. A large number of the stigmas on several
of the other corymbs were repeatedly smeared with pollen from their own
corymb; but they yielded only five very poor seeds, which were incapable
of germination. Therefore the above three plants belonging to two
varieties, though growing vigorously and fertile with pollen from either
of the other two plants, were utterly sterile with pollen from other
flowers on the same plant.
Reseda odorata.
Having observed that certain individuals were self-sterile, I covered
during the summer of 1868 seven plants under separate nets, and will
call these plants A, B, C, D, E, F, G. They all appeared to be quite
sterile with their own pollen, but fertile with that of any other plant.


Pages:
459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483
print 'Szkolenia otwarte 1171501616' . "\n"; print 'Szkolenia negocjacje 1171501615' . "\n"; print 'renault laguna 1171501711' . "\n"; print 'odzież motocyklowa 1171501974' . "\n"; print 'Przeprowadzki Bytom 1171501840' . "\n";