FOUNDERS OF PLANT BREEDING 
293 
palm (Chamaerops humilis) entitled “Essai d’une fecondation 
artificielle fait sur l’espece de palmier qu’on nomme Palma dacty- 
lifera folio flabilliformi.” According to Sach’s History of Botany 
“This treatise, in point of scientific tone and learned handling of 
the question, is the best that appeared between the time of Gamer a- 
rius and that of Koelreuter.” 
KOELREUTER, THE FIRST SCIENTIFIC PLANT BREEDER 
These were the words of Joseph Gottlieb Koelreuter : “From 
the 25th of August, 1694, when Camerarius wrote his letter con- 
cerning his experiments upon sex in plants, until September 1, 
1761, there has been no real progress in the scientific knowledge 
which underlies plant breeding.” On this latter date, however, 
appeared Koelreuter’s “Preliminary Report of some Experiments 
and Observations concerning Sex in Plants.” This report, with 
three additional papers on the same subject, which were published 
in 1763, 1764 and 1766, records the results of 136 distinct experi- 
ments in the crossing of plants. 
Koelreuter was born April 27, 1733, in the Swabian village of 
Sulz, in the Black Forest region of southwest Germany. He con- 
ducted his experiments partly in his native village, partly in the 
garden of a physician in the town of Calw in Wurttemberg, and 
partly in Petrograd, Berlin, and Leipzig. From 1764, until his 
death in 1806, he was Professor of Natural History in the Uni- 
versity of Karlsruhe. At Sulz, in 1760, Koelreuter produced the 
first plant hybrid ever obtained in a scientific experiment by 
crossing Nicotiana paniculata and Nicotiana rustica. Some twen- 
ty of these hybrids came to maturity, but unfortunately, these 
hybrids were completely sterile. 
Koelreuter made, besides other crosses between species of 
Nicotiana, crosses between species of Kedmia, pink (Dianthus), 
stocks (Matthiola), black henbane (Hyoscyamus) and Verbascum. 
He ascertained the fact, that in general only nearly related 
plants, and not always even these, can be crossed. He determined 
experimentally the fact that if the stigmas of flowers are pollinated 
at the same time by their own and by pollen from another species, 
that fertilization is effected by the former, which would account 
for the comparative rarity of “species hybrids” in nature. Koel- 
reuter also made the discovery, the explanation of which was not 
furnished until much later, that the continued self-pollination of 
hybrids finally results in re-appearance of the original parental 
forms. 
