THE FOUNDERS OF THE 



ART OF BREEDING— II 



Work of the Earlier Hybridists — Other Great Discoverers Long Neglected, as 



Was the Case with Mendel 



Herbert F. Roberts 

 Kansas State Agricultural College 



of 



IN A previous article/ the writer 

 described the early work in plant 

 breeding, which came about through 

 the accidental contact of the people 

 Mesopotamia with the date palm, 

 the discovery thereby of the fact of sex 

 in plants, which underlies breeding, and 

 Camerarius' scientific investigations 

 upon plant sex. The present article 

 deals with the work of some of the 

 earlier hybridists, whose experiments 

 determined the course of the art of 

 plant breeding before Mendel's time. 



koelreuter, the first scientific 



PLANT breeder 



Camerarius' now famous Latin letter 

 fell on sterile, or rather on unprepared 

 soil. Over half a century had to pass 

 by before one was found to speak his 

 praise. "Rudolf Jacob Camerer is in- 

 disputably the first who proved the sex 

 of plants through his own experiments, 

 instituted with this idea in view. 

 In this manuscript (the letter to Valen- 

 tin), which far surpasses in thorough- 

 ness, completeness and good execution, 

 almost all the writings of this nature 

 which have thus far come to light up to 

 the present day, he appeared to have at 

 once exhausted everything which might 

 have been said on the subject up to his 

 time." These were the words of Joseph 

 Gottlieb Koelreuter: From the 25th 

 of August, 1694, when Camerarius 

 wrote his letter concerning his experi- 

 ments upon sex in plants, until Septem- 

 ber 1, 1761, there had been no real 

 progress in the scientific knowledge 

 which underlies plant breeding. On this 



^Journal of Heredity, vol. x, p. 99, 



latter date, however, appeared Koel- 

 reuter's "Preliminary Report of some 

 Experiments and Observations concern- 

 ing Sex in Plants "(4). This report, 

 followed in 1763, 1764, and 1766, by 

 three additional papers on the same 

 subject, record the results of 136 dis- 

 tinct experiments in the crossing of 

 plants. 



If Camerarius made the actual scien- 

 tific discovery of sex in plants, Koel- 

 reuter was the first to apply this dis- 

 covery to their scientific breeding. 

 Koelreuter was born April 27, 1733, in 

 the Swabian village of Sulz, in the 

 valley of the Neckar, in the Black 

 Forest region of southwest Germany. 

 He conducted his experiments partly in 

 his native village, partly in the garden 

 of a physician in the town of Calw in 

 Wiirttemberg, and partly in St. Peters- 

 burg, Berlin, and Leipzig. From 1764, 

 until his death in 1806, he was Pro- 

 fessor 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. 



THE FIRST "mule" PLANT 



In Koelreuter 's quaint German, we 

 read of the reasons which led him to 

 experiment upon the breeding of plants. 

 He calls attention to the fact that man 

 has brought together into botanical and 

 zoological gardens, plants and animals 

 from all quarters of the earth. With 

 animals, this has given rise to the 

 possibility of making hybrids. "Would 

 a goldfinch ever have mated with a 



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