524 JOURNAL OF THE KOYAL HORTICULTURAL SOCIETY. 



Vines. 



Vine, Investigations on the Ripening" of the Canes in. 



(Recherches Biologiques sur Aoiitenient des Sarments de la Vigne.) By 

 F. Kovessi {Bev. gen. Bot. xiii. p. 193, with plates 3-9, and figures in the 

 text). — The author discusses the various characters, both external and 

 anatomical, which distinguish well-ripened from badly-ripened canes of 

 the vine, and points out the very difierent values they respectively 

 possess as either materials for grafting or as fruit-bearers. The vines 

 chiefly dealt with are the various races of Vitis vinifera and V. rupestris, 

 the latter of which has been used in some parts of France to replace the 

 sorts killed out by the phylloxera. 



Dealing with the anatomical differences, he points out that in well- 

 ripened canes the elements of the woody tissues possess thick walls as 

 contrasted with those of the pith and of the cambium. In badly-matured 

 specimens this difference is less well marked, and the degree of its 

 accentuation may be taken as a guide in estimating the completeness with 

 which the ripening processes have been carried through. This relation 

 between the character of the cells and the condition of matureness is 

 preserved under whatever kind of environment the plants to be compared 

 may have been cultivated. 



Again, the starch-grains, which are stored in the tissues as reser\ e food, 

 exhibit a disparity in average size which is related to the condition in 

 question of the canes, being larger in those which have been properly 

 ripened, and a similar difference is shown between the total amount of 

 reserve food per unit weight of the two kinds of stems. Thus specimens 

 gathered and investigated in winter showed a difference exceeding 50 per 

 cent, between the amount of food stored in corresponding parts, measured 

 by volume, of well- and badly-ripened canes. 



M. Kovessi then deals with the influence of the various external 

 factors which are concerned in bringing about this difference, and con- 

 siders them also in relation to the inherent character of the different, 

 varieties of the vines which were investigated. Foremost amongst the 

 external influences is naturally that of climate, involving as it does the 

 factors of heat, light considered both with regard to intensity and 

 duration, and the humidity of the air and the soil. 



Interesting details as to the relations between temperature and growth 

 are given. Thus it was found by Angot that in the case of the ordinary 

 vines, a daily average temperature of 12° C. suffices to cause the buds to 

 push, and correspondingly in autumn, when the average temperature 

 sinks to the same degree, the leaves fall oft'. Hence it is clear that, other 

 things being equal, a consideration of the temperature curves for any 

 given locality may indicate its relative suitability for the cultivation of 

 the vine. For if the minimal temperature is reached earlier in one place 

 than another, and in the autumn is similarly postponed, the period of 

 vegetation will likewise be correspondingly lengthened. 



The importance of the internal factor, w^hich must always be borne in 

 mind in dealing with statistics of this kind, is emphasised by the 

 behaviour of the Pinot variety of vine, which is cultivated in the North 

 of France. For its minimal temperature is 10° C, or two degrees lower 



