52 MISSOURI AGR. EXP. STA. RESEARCH BULLETIN NO. 17 



Schneider-Orelli J treated refractory seeds with sulphuric acid r 

 thereby increasing the germination from 15 to 75 per cent. 



Love and Leighty 2 tested the effects of concentrated sulphuric 

 acid upon the seeds of red clover, white clover, alfalfa and cotton. 

 The acid treatment caused increased germination, and at the same 

 time destroyed obnoxious weed seeds. Increased germination was 

 brought about chiefly through the softening of the testa of the so- 

 called "hard" seeds. The favorable effects of acid on the seeds con- 

 tinued even after they were allowed to become dry. The acid treat- 

 ment caused old seeds to germinate quicker and better. However, it 

 was found that thin coated seeds might be injured by the treat- 

 ment. 3 



Organic acids have been found to increase and accelerate the 

 germination process in seeds. It was believed that these treatments 

 contributed to the nutrition of the growing embryo. 4 



Stone and Smith 5 (1895) attempted to stimulate the germination 

 of seeds by subjecting them to various enzymic solutions. Asparagin 

 and leucin increased the percentage of germination, and sometimes 

 accelerated germination. Pepsin solutions gave fair results with some 

 seeds, but negative results with others. Diastase, one of the most 

 widely distributed enzymes, gave beneficial results with some seeds, 

 but with others did not. The tests seemed to show that no one enzyme 

 is beneficial to all seeds. 



Waugh, 6 confirming the early works of Thomsen, reports that 

 the percentage of germination of some seeds may be greatly increased 

 by soaking for several hours in a solution containing some active 

 enzyme. Tomato seeds seemed to respond exceptionally well to the 

 action of diastase. 



Pickering 7 found that heating a soil seems to have the effect of 

 retarding the germination of seeds planted in it. This was supposed 

 to be due to an inhibitory substance formed by the alteration of the 

 bacterial content of the soil. The fact that heating a soil increases 

 the soluble organic and nitrogenous matter present and also that these 

 materials form a large proportion of the inhibitory substance, lends 



1. Schneider-Orelli, Exp. Station Record, Vol. 24, p. 231. 



2. Love and Leighty, N. Y. (Cornell) Agr. Exp. Sta. Bui. 312. 



3. Experiment Station Record, Vol. 37, p. 132. 



4. Experiment Station Record, Vol. 25, p. 222. 



5. Stone and Smith, An. Rpt. Mass. (Hatch) Exp. Sta. 1901, pp. 74-79 



6. Waugh, An. Rpt. Vermont Agr. Exp. Sta. 1898, pp. 290-5. 



7. Pickering, 9th An. Rpt. Woburn Exp. Fruit Farm. 



