732 EXPERIMENT STATION EECOKD. 



cent of the nitrogen, 23.8 per cent of tlie PjOe, and 20.4 per cent of the K2O 

 were utilized by the crop. 



It is noted that in the rotations without fertilizers, but including the fallow, 

 the annual available plant food was not increased, but that the accumulation due 

 to fallow made possible larger yields for the 3 succeeding years than for the 

 4-year rotations without the fallow. When fertilizers were applied, however, 

 it was found that the rotation including fallow fell behind in yields. In a 

 series of 6-year rotations of cereals and sugar beets, the introduction of a vetch 

 crop was followed by greater total yields than either fallow or green manure 

 in the rotation. In this last series it was determined that 62.3 per cent of the 

 nitrogen and 47.5 per cent of the PzOs were utilized by the crop with the 

 rotation including the fallow. With the rotation including the green manure 

 it was found that 48.2 per cent of the P2O5 and 40 per cent of the nitrogen were 

 utilized, and with the rotation including the vetch crop 61.4 per cent of the 

 P2O5 and 62 per cent of the nitrogen. It is noted that barley gave larger yields, 

 and richer in protein, following winter wheat than when following sugar beets. 



The shooting of winter rye and winter wheat when spring sown, A. 

 MuEiNow (Zhur. Opyin. Agron. {Russ. Jour. Expt. Landio.), I4 {1913), No. ^ 

 pp. 238-254, figs. 2). — Experiments conducted in the greenhouse and in the field 

 at the Moscow station showed (1) that spring- sown winter cereals may shoot' 

 without a rest period; (2) that the greater the environmental influences, the 

 smaller the number of plants that came to head; and (3) that the influence of 

 a low temperature was to decrease the number of plants that headed, appa- 

 rently due to checking vegetative growth. As the greenhouse-grown plants 

 were able to shoot without a rest period and the field-grown plants took a rest 

 period, the author concluded that temperature was the factor that governed 

 the rest period in winter cereals. 



The influence of spacing on the development of single plants, E. Spekling 

 {FiihUng's Landio. Ztg., 62 {1913), No. 14, pp. 487-499).— In general, with 

 wheat, rye, barley, and oats the total weight of plants increased with the in- 

 crease in spacing, which ranged from 75 sq. cm. to 400 sq. cm. per plant. With 

 rye, barley, and oats the weight on 400 sq. cm. of space was double that on 200 

 sq. cm. of space. The weight of grain did not increase so rapidly with increased 

 space, and the percentage of grain to straw and chaff decreased. The average 

 single kernel weights of all the cereals, except spring wheat, increased with 

 the increase in space. With horse beans the total weight of plants and the 

 number of beans per pod increased with the increase in spacing, which ranged 

 from 200 to 1,600 sq. cm. The weight of beans increased more rapidly than the 

 weight of straw and chaff. The percentage of beans to straw and chaff was the 

 reverse of that of the cereals, it being the smallest with the smallest space 

 and reaching the maximum at 800 sq. cm. 



Plant breeding from the scientific standpoint, R. Regkl {Trudy Bmro 

 Prild. Bot. {Bui. Angeic. Bot.), 5 {1912), No. 11, pp. 425-623; Beilage, 1912^ 

 Nov., pp. 18, pis. 18). — This work constitutes a discussion of the laws of 

 heredity in their relation to the morphological and biological characteristics 

 of plants, with special reference to cereals and to barley in particular. The 

 findings and opinions of the leading investigators are noted in regard to the 

 nonvariability of inherited factors, the general value of Mendel's law of segre- 

 gation of characteristics, tlie prediction of inheritance in plant form, the evo- 

 lution of the organism, systematic (taxonomic) factors, and the general prin- 

 ciples of plant breeding. 



Selection in pure lines, Mrs. C. and A. L. Hagedoorn {Amer. Breeders Mag., 

 .^ {1913), No. 3, pp. 165-168, fig. 1). — This points to results obtained by Vilmorin 



