ANNUAL REPORT, 1933 13 



Onion Breeding. (M. E. Snell.) The past season some of the better yielding 

 inbred strains were planted on fair-sized plots for comparison with some of the 

 better commercial varieties grown locally. Since the season was very unfavorable 

 for seed onion production, the yields were very small and poor in all cases, but 

 the commercial varieties were generalh' superior to the inbred strains. 



For the first time bulbs selected from first -generation hybrids were planted 

 for seed production. Many of the bulbs showed good vigor as compared with 

 the inbred strains. Sets had also been grown from inbred strains and were 

 planted for bulb production. The growing plants from the sets were remarkably 

 uniform in type and in most cases had some outstanding characteristics. This 

 phase of the breeding work should not be overlooked, as it appears that the prin- 

 cipal way in which onions are to be grown in this section is from sets. Sets also 

 offer much more satisfactory material for this work than seed onions which often 

 give very unsatisfactory >ields necessitating the use of undersized and poor 

 bulbs for seed production. With sets there is, of course, the difficulty of growing 

 good sets for planting from only a small amount of seed. 



The past season the bulbs for crossing were grown in the station glasshouse 

 on cars which could be pushed in or out as desired. This permitted the pollina- 

 tion of flowers in wet weather as well as fair, and a much better set of seed was 

 obtained than previously. 



Toxicity of Aluminum for Tobacco. (Walter S. Eisenmenger.) Tobacco 

 plants were grown in aluminum citrate solutions. These plants grew in a com- 

 plete nutrient solution for two days, and on the succeeding two days the phos- 

 phates were withheld and various concentrations of the aluminum salt were 

 added— 0, 2, 5, 15, 30, 50, 70, 85, 95, 98, and 100 per cent of 0.006 M. Toxicity 

 was indicated in dry weight of tops and roots. 



At present the antagonistic effect of the calcium ion on the aluminum ion in 

 the nutrient solution is being determined. 



The Toxicity of Aluminum for Seedlings, and the Action of Certain Ions in 

 the Elimination of the Toxic Effects, (Walter S. Eisenmenger.) Seedings of 

 corn, soybeans, and buckwheat were grown in various concentrations of aluminum 

 citrate and aluminum tartrate. The concentrations were 2, 5, 15, 30, 50, 

 70, 85, 95, 98, and 100 per cent of 0.006 M of the aluminum salt. Fifty seedlings 

 were used for each concentration, 50 were grown in distilled water, and 200 were 

 grown in a complete nutrient solution. The comparison of those grown in a 

 complete nutrient solution with those grown in the aluminum salt solution in- 

 dicated that the toxicity of the salts increased with increased concentration, but 

 the degree of toxicity was much less pronounced above 30 per cent of 0.006 M. 



Both the hydroxy! and the calcium ions were factors in overcoming the toxicity 

 of the aluminum salts. By adjusting the pH of the nutrient solution with citric 

 acid to make it comparable to the pH of the aluminum salt solutions, it was 

 found that the aluminum ion was more of a factor in growth retardation than 

 the hxdrogen ion in aluminum salt solutions. 



Distribution of Nitrogen in Infusions of Plants. (Walter S. Eisenmenger.) 

 Water infusions of different plants were made in the greenhouse, the plants being 

 kept in the crocks of water for seven weeks. The water or colloidal solution was 

 then filtered off and analyzed for different forms of nitrogen. Except for one 

 corn stover which was simply ground up after it had been kept for one year in a 

 barn, the plants comprised the mature plants including roots and tops, and were 

 timothy, red clover, red top, tobacco, and corn. The latter consisted of the 



