ALFALFA BREEDING FOR DROUGHT RESISTANCE. 



17 



COMPARATIVE YIELDS <* OF THE DIFFERENT STRAINS AND PROGENIES. 



Table I. — Uniformity and seed yield of plants of alfalfa grown in progeny rows at Belle- 



fourche, S. Dak., in 1909. 





Progeny 

 No. 



Proportion 

 of typical 



Average 



Average 



Seed yield 



per 100 



grams of 



dry plant. 



Strain. 



plants in 



dry weight 



seed yield 

 per plant. 





progeny 

 rows. 



per plant. 







Per cent. 



Grams. 



Grams. 



Grams. 



A 



1 ' 



91 



138 



21 



15.2 





2 



88 



129 



16 



12.4 



B 



1 



92 



153 



12 



7.8 



C 



1 



82 



150 



14 



9.3 





2 



81 



150 



21 



14.0 





3 



79 



135 



16 



11.9 





4 



85 



132 



20 



15.1 



D 



1 



89 



138 



13 



9.4 





2 



85 



123 



17 



13.8 



E 



1 



79 



171 



27 



15.8 





2 



84 



171 



18 



10.5 





3 



4 



72 



88 





23 

 33 





'"'189" 



ii'.b" 





5 



80 



144 



23 



16.0 





6 



82 



192 



32 



16.7 





7 



80 



150 



25 



16.7 





9 



91 



150 



22 



14.7 





10 



90 



138 



22 



16.0 





12 



100 



150 



21 



14.0 





13 



95 



138 



19 



13.8 





15 



74 



180 



27' 



15.0 





16 

 17 



83 



85 





28 

 20 





138" 



ii'5" 





18 



66 



165 



28 



17.0 





19 



84 



180 



33 



18.3 



F 



1 



85 



144 



18 



12.5 





2 



76 



150 



20 



13.3 





3 



81 



150 



19 



12.7 





5 



87 



135 



14 



10.4 





6 



87 



132 



15 



11.4 





7 



91 



134 



22 



16.4 





8 



83 



192 



28 



14.6 





9 



57 



144 



17 



11.8 





10 

 11 



85 

 82 





21 



20 





'"l44" 



13.9" 





12 



91 



180 



30 



16.7 



The results given in Table I were obtained from a large number of 

 plants. Where the progeny occupied two rows of the breeding 

 nursery the number of plants harvested in the bulk lot exceeded 100. 

 Where the progeny occupied one row the number of plants usually 

 exceeded 50, but where less than a row was planted the report shows 

 the yield of only 20 to 50 plants. Yields estimated on more than 

 50 plants should represent fairly the producing power of the progeny 

 under this system of planting. Column 3 of Table I shows the per- 

 centage of plants of uniform type in the progeny row, leaving out of 

 consideration the inferior plants which were discarded early in the 

 season. 



The dry weight of the plants and the seed yield have been reduced 

 to an average per plant so as to afford a comparison of the producing 



a The yields obtained in the breeding nursery, where each plant has much more 

 space than in ordinary field culture, do not necessarily indicate that under field 

 conditions the different strains will be found to occupy the same relation to each 

 other in comparative yielding power. 

 58575°— Bui. 196—10 3 



