17 



ScHAFFNiT (E.). Die Stockkrankheit des Roggens und des Klees 



( Tylenchiis dipsaci, Kiihn = T. devastatrix, Kiihn), [The Nematode 

 Disease of Rye and Clover {T. dipsaci).] — Bericht Auftreten v. 

 Feind. u. Krankh. d. KidUirpfl. in d. Rheinprov. 1918 u. 1919, 

 pp. 49-53. (Abstract in Ccntralbl. Bakt. Paras. Infekt., Jena, 

 lite Abt., liv, no. 11-19, 2nd September 1921, pp. 378-379.) 

 In various districts of the Rhine province cereals, especially winter 

 rye, are considerably injured by a Nematode, Tylenchiis dipsaci, 

 Kiihn. The infestation begins when two or three leaves are formed on 

 the plant. After the harvest, in late summer and in autumn, the eel- 

 worms return to the ground, only a few remaining in the stalks. In 

 dry ground they remain in a state of suspended animation until they 

 are able to resume development. Under these conditions they die 

 after about two and a half years. To combat them it is necessary to 

 clear away all weeds, to arrange a suitable crop rotation, and to grow 

 root-crops repeatedly, as these drive them to a greater depth, where 

 there is more moisture. This has the effect of restoring animation and 

 of causing their death from lack of food. Trap-crops are also useful, 

 and the sowing of winter rye in mid-October is advised. Manuring 

 must aim at developing the young plants quickly in the stages in which 

 they are most likely to be injured. Saltpetre is good for this purpose, 

 while stable manure should only be used for crops that are not suffering 

 from infestation. In May 1915 and 1916 the author made experiments 

 in soil disinfection with hydrocyanic acid, produced by placing sodium 

 cyanide in the ground, and he obtained surprisingly good results. 



PosTELT (A.). Der GetreidelaufkaSer, Zabrus gibbus. [The Corn 



Beetle, Z. gibbus.] — Wiener landwirfsch. Zfg., Ixviii, 1918, p. 87. 

 SiEGMUND (G.). Das Auftreten des Getreidelaufkafers in Mahren. 



[The Occurrence of Z. gibbus in Moravia.] — Ibidem, p. 334. 

 Skutecky (G.). Das Auftreten des Getreidelaufkafers in Mahren. 

 [The Occurrence of Z. gibbus in Moravia.] — Ibidem, p. 387. 

 (Abstracted in Centralbl. Bakt. Paras. Infekt., Jena, Ilte Abt., 

 liv, no. 11-19, 2nd September 1921, pp. 379-380.) 

 In the autumn of 1917 an outbreak of a beetle, Zabrus gibbus, 

 occurred in Moravia. The only means of actually getting rid of 

 this pest is a thorough change in crop rotation. The beetle was most 

 abundant in one district, where rye is grown after barley ; in higher 

 localities, where the poorer soil cannot stand such exacting 

 crop rotation, and rye follows clover or potatoes, no injury is done 

 to winter crops. One of the authors (Skutecky) considers the accepted 

 life-cycle of three years to be incorrect. Spraying with Paris green, 

 chloride of lime, or arsenicals has been recommended. 



Jablonowski (J.). Mi modon bantja a hassziai legy agabonanov^nytn'? 



[How does the Hessian Fly attack Corn .?] — Rovartani lapok, 

 xxiv, 1917, pp. 1-4. (Abstract in Centralbl. Bakt. Paras. Infekt., 

 Jena, lite Abt.. liv, no. 11-19, 2nd September 1921, p. 397.) 



The oat midge, Mayetiola avenae, lays more than 20 eggs in autumn ; 

 the larvae soon hatch and crawl down the leaf to the leaf-sheaths, 

 where they feed and rapidly harden, so that they cannot be suffocated 

 by the growing plant. The Hessian fly [Mayetiola destructor] also 

 travels downwards to the lowest joint in the stem that is enveloped 

 by the leaf-sheath. At this point its presence so weakens the stem 

 that it breaks in the slightest wind. 



(5155) B 



