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 225 | Next

Darwin, Charles, 1809-1882

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

He enclosed several flowers in
bags; and as the buds often dropped off, he attributes the partial
sterility of these flowers to the injurious effects of the bags, and not
to the exclusion of insects. But the only safe method of experimenting
is to cover up a whole plant, which then never suffers.
Self-fertilised seeds were obtained by moving up and down in the same
manner as bees do the wing-petals of flowers protected by a net; and
crossed seeds were obtained by crossing two of the plants under the same
net. The seeds after germinating on sand were planted on the opposite
sides of two large pots, and equal-sized sticks were given them to twine
up. When 8 inches in height, the plants on the two sides were equal. The
crossed plants flowered before the self-fertilised in both pots. As soon
as one of each pair had grown to the summit of its stick both were
measured.
TABLE 5/53. Phaseolus multiflorus.
Column 1: Number (Name) of Pot.
Column 2: Crossed Plants.
Column 3: Self-fertilised Plants.
Pot 1 : 87 : 84 6/8.
Pot 1 : 88 : 87.
Pot 1 : 82 4/8 : 76.
Pot 2 : 90 : 76 4/8.
Pot 2 : 82 4/8 : 87 4/8.
Total : 430.00 : 411.75.
The average height of the five crossed plants is 86 inches, and that of
the five self-fertilised plants 82.35; or as 100 to 96. The pots were
kept in the greenhouse, and there was little or no difference in the
fertility of the two lots.


Pages:
213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237
print 'Choroby oczu 1171501765' . "\n"; print 'Leczenie cukrzycy 1171501764' . "\n"; Rusztowania 110011001 print 'hdi oc 1171501671' . "\n"; print 'budowa domów jednorodzinnych 1171501856' . "\n";