HORTICULTUEE. 539 



complete failure. A lack of this knowleclge has been responsible for heavy 

 losses in reconstituting California vineyards. 



Extensive saccharine and acid determinations show a close correspondence 

 between these constituents of the fruit and the congeniality of stock. Similar 

 growth ratings of a variety grafted on different stocks are accompanied by 

 fairly definite percentages of sugar and acid. Congeniality of the variety to the 

 stock materially affects the resistant qualities of the stock. 



Quantity and quality of the fruit are usually in opposition on the soils and 

 vines producing most abundantly. Most vine varieties making perfect growth 

 on resistant stocks are found to yield heavier crops than the same variety 

 grown on its own roots. The relative rooting qualities of resistant varieties 

 are an important consideration in the cost of establishing resistant vineyards. 

 Some stocks are suitable for bench grafting while others are especially valu- 

 able for vineyard grafting. Of the various stocks tested Riparia, Berlandieri, 

 Champiui, and Aestivalis are in most instances congenial to Vinifera varieties. 

 Fruitfulness of these varieties is increased and the time of ripening hastened in 

 comparison with the same varieties grown on other stocks. 



Some of the hybrid resistant-stock varieties are making enviable records as 

 stocks under California conditions. Where all the qualities desired can not be 

 found in a hybrid a complex hybrid may yield the desired results. A number 

 of new grape introductions by this Department are proving to be superior to 

 the varieties now commercially grown for certain purposes. 



Physiolog-ical research on pollen g'ermination in Vitis vinifera, E. Gaeino- 

 Canina (Staz. Sper. Agr. Ital., 47 (.1914), No. 7, pp. 4Sl-492).—The investiga- 

 tion here reported confirms the author's earlier results (B. S. R., 29, p. 839) 

 with reference to a more or less toxic effect of most spray mixtures commonly 

 used on grapes. In conducting laboratory studies a medium containing 15 per 

 cent saccharose and 2 per cent neutral gelatin, acidulated with tartaric acid 

 solution (1:4,000), was found to be the best for germinating pollen grains. 

 The prolonged action of rain appears to cause the explosion of pollen grains 

 and tubes through the dilution of the glucose-acid fluid. This phenomenon 

 may be reproduced experimentally by germination of pollen grains in distilled 

 water. Temperatures inferior to 14° C. and superior to 35° durihg the period 

 of fecundation are able to bring about infecundity, the lower temperatures 

 preventing germination and the higher temperatures causing abnormal develop- 

 ment of the pollen tubes. The author points out that there should be no inde- 

 cision as to the use of spray mixtures when choosing between a possibility of 

 pollen sterility and a certainty of mildew attack. 



Viticulture in Japan, Y. Oinoue (Inform. Agr. [Madrid], 5 (1915), No. 100, 

 pp. lJf5-148, figs. 3). — A short descriptive account of viticulture in Japan with 

 special reference to the kinds of grapes grown and those susceptible and re- 

 sistant to disease. 



Some recent experiments on the conservation of grapes in various gases, 

 G. Dalmasso (Rivista [Conegliano], 5. ser., 21 (1915), No. 10, pp. 217-219).— 

 Experiments conducted by the author during 1914 and here briefly summarized 

 indicate that the conservation of grapes in a confined atmosphere of either car- 

 bonic acid, deoxygenated air, ozonized air, or pure oxygen is not feasible since 

 deterioration sets in and. unpleasant flavors are developed in less than two 

 months' time. 



Statistics on the production of grapes and olives in 1914 (Estadistica de 

 las Producciones Viticola y Olivarera en el Ano 191.^. Madrid: Govt., 1915, pp. 

 9). — This is the usual statistical review relative to the production of grapes, 

 wine, olives, and. olive oil in Spain (E. S. R., 31, p. 238). 



