12 BULLETIN 1011, U. S. DEPARTMENT OF AGRICULTURE. 



The plants from the mutilated seeds were shorter and weaker in 

 appearance than those from the entire seeds during the first six or 

 eight weeks of growth. Later, the differences in height largely dis- 

 appeared, and when harvested the different lots were approximately 

 of the same average height. In general, the plants from the entire 

 seeds were the most vigorous throughout the season, although there 

 were exceptional plants from the injured seeds that equaled them. 



In United States Selection No. 193 the plants from the injured seeds 

 were inferior to the plants from the entire seeds in average production 

 to the plant and in average weight of ear but surpassed the check 

 plants in number of ears to the plant except those from the cross 

 sections, which were inferior in every respect. The number of nodes 

 above ground was slightly less in the plants from the injured seeds 

 than those from the entire seed: 



The data on the yields and prolificacy shown in Table III have been 



presented as evidence of the extent to which plants from seeds so 



severely mutilated could recover to a condition of normal growth and 



reproduction rather than as a comparison of the productivity of the 



different lots of seed. 



SUMMARY. 



The effects of the mutilations of the seed coats and endosperms 

 may be summarized as follows : 



(1) The stands were less than from the check seed. The poorest 

 stands were obtained from the dehulled seed. This was not due to 

 decreased viability, but evidently to weakened ability to withstand 

 field conditions. 



(2) Seedlings from mutilated seed in general were smaller than 

 those from the check seed. The least difference was between the 

 starchless class and the check. In some instances the seedlings from 

 the two classes were not distinguishable in size and vigor. Seedlings 

 from the dehulled class were noticeably smaller than those from the 

 check seed. .Seedlings from the germs were much smaller, more 

 slender, and had narrower leaves than those from the check seed. 



(3) The height of plants at maturity was not definitely affected, 

 and it bore no consistent relation to the height of the check plants. 



(4) The development of the plants was retarded, pollen shedding 

 and ripening, in general, being later than in the checks. 



(5) The average number of ears to the plant was reduced. The 

 only exception was the dehulled class, which exceeded the check in 

 the general average. 



(6) The average weight of ears and the yield of the plant were less 

 than in the checks. The degree of reduction was fairly consistent 

 with the extent of the mutilations. 



(7) The reductions in yield were equivalent to 7 to 10 bushels to 

 the acre. 



