NOTES ON EECENT RESEARCH. 



693 



Weather Influence on Fungi. 



Fungus Diseases in Relation to Weather. By K. Saj6 (Zeit. f. 

 Tflanz. xi. 1901, pp. 92-95, and xii. 1902, pp. 151-157).— An interesting 

 attempt to correlate climatic conditions with the prevalence of parasitic 

 fungi in vineyards in Hungary. The most common fungus pest in 1899 

 was Powdery Mildew (Oidium Tuckcri) ; in 1900 downy mildew (Pcrono- 

 spora viticold) ; in 1901 white rot (ConiothyriiimDiplodiclla). 1899 was 

 distinguished by prevalence of south-west or west winds, low temperature, and 

 low pressure of atmospheric moisture from May to August ; 1900 by an 

 absence of south-west and west winds, by high temperature, and high 

 pressure ; 1901 by prevalence of easterly winds during the period of 

 vegetation, by great heat (especially in May, June, and July), and by 

 abnormally high rainfall (sometimes hail) in July. The statistics from 

 which these conclusions are drawn are given, viz. temperature, barometric 

 pressure, rainfall, and pressure of atmospheric moisture for the months 

 April to July. — W. G. S. 



Influence of Graft on Stock. 



Graft on Stock, Influence of. By G. T. Grignan (Bee. Hort. 

 pp. 414-G ; September 1, 1902). — This article is really a resume of results 

 so far obtained by heterogeneous graftings, with special reference to a 

 paper of ninety pages, presented by M. Daniel, on " Les Variations 

 specifiques dans la Greffe " at the Vine-hybridisation Conference held at 

 Lyons in November 1901. By ordinary grafting, with which M. Daniel 

 has mainly dealt, he has united together Tomatos of different varieties, 

 Aubergine and Tomato, Pimento on Tomato and Aubergine, various 

 Potatos, various Pears, Eoses, sundry Composites, especially Sunflowers, 

 Crucifers (Cabbages of various kinds and Turnips &c), Vines, &c, and 

 has thereby obtained very marked and extremely interesting specific 

 variations. Thus the long violet Aubergine grafted on a ribbed Tomato 

 has yielded round ribbed fruits. New strains have been obtained which 

 are distinct and more or less intermediate as to habit, inflorescence, 

 fruit, and tubers, &c. Helianthus tuberosus (perennial Sunflower) grafted 

 on H. animus (annual Sunflower) has yielded particularly interesting 

 results : the annual stock became perennial and assumed to a large 

 degree the character of the scion, adventitious roots appeared on the graft 

 at the bud point, partly penetrated the tissues of the stock, and became 

 completely amalgamated therewith. Allusion is made to the Bronveaux 

 Medlar as a characteristic example. Very interesting variations have 

 been noted also in the variegation of the stock or the scion in precocity 

 of flowering, in fruitfulness (M. Daniel having succeeded in producing 

 Grapes in abundance on infertile varieties — varietes coulardes — and seeds 

 of the Cauliflower), in resistance against parasites, cold, &c. 



These facts, which can only be briefly touched upon, led M. Daniel to 

 the conclusion that grafting cannot always be relied upon as a means of 

 maintaining varieties, strains, or hybrids intact, but may, on the other 

 hand, be a potent cause of variation itself. 



These results would be of minor importance were they limited to the 

 individual, but in many cases the acquired characters can be fixed by 



