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 550 | Next

Darwin, Charles, 1809-1882

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

(10/39. With respect to Messrs. Sharp see 'Gardeners'
Chronicle' 1856 page 823. Lindley's 'Theory of Horticulture' page 319.)
Only two trials were made by me to ascertain after how long an interval
of time, pollen from a distinct variety would obliterate more or less
completely the action of a plant's own pollen. The stigmas in two lately
expanded flowers on a variety of cabbage, called Ragged Jack, were well
covered with pollen from the same plant. After an interval of
twenty-three hours, pollen from the Early Barnes Cabbage growing at a
distance was placed on both stigmas; and as the plant was left
uncovered, pollen from other flowers on the Ragged Jack would certainly
have been left by the bees during the next two or three days on the same
two stigmas. Under these circumstances it seemed very unlikely that the
pollen of the Barnes cabbage would produce any effect; but three out of
the fifteen plants raised from the two capsules thus produced were
plainly mongrelised: and I have no doubt that the twelve other plants
were affected, for they grew much more vigorously than the
self-fertilised seedlings from the Ragged Jack planted at the same time
and under the same conditions. Secondly, I placed on several stigmas of
a long-styled cowslip (Primula veris) plenty of pollen from the same
plant, and after twenty-four hours added some from a short-styled
dark-red Polyanthus, which is a variety of the cowslip.


Pages:
538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562
print ' wynajem busów Warszawa print 'pzu oc 1171501698' . "\n"; print 'programator 1171501848' . "\n";