Vol,. XVI. No. 409. 



THE AGRICULTURAL NEWS. 



415 



formation of huge or very numerous gas bubbles under the 

 transparent skin of the fruit, replacing the pulpy tissues as 

 they were rapidly broken down Finally the whole content 

 of the fruit except the seeds was reduced to slime and gas, 

 which escaped sooner or later by the rupture of the pendant 

 skin, leaving the latter empty on the stalk. Needle point 

 inoculation of hilf-ripe fruits in the evening gave rise to 

 a hollow an inch in diameter in two or three hours, and by 

 next morning the process was complete. Smearing of the 

 skin with the slime produced did not cause infection unless 

 a crack or other wound was present. The natural infections 

 •examined appeared to have their origin in bug punctures, 

 made by Neiara and Leptoglossus. 



Apparently pure growths of the bacterium were obtained 

 by transfers from one fruit to another, and consisted of long 

 actively moving rods. Cultures were obtained on nutrient 

 agar, but time could not be spared from other work to 

 continue the study further. Inoculations from diseased 

 fruits into succulent stems had no cftect. 



No previous record has as yet been seen of a disease 

 answering to this description. 



W.X. 



PINE-APPLE SEEDLINGS. 



The pine-apple is one of the fruits, like the banana, 

 ■which seems to have been so cultivated by forgotten races 

 from prehistoric times as to have lost the power, except in 

 rare instances, of producing seed. Seeds are, however, some 

 times produced, and in considerable quantities, by rare indi- 

 viduals. Originally, in historic times at least, found in the 

 Western Tropics, the pine-apple is now cultivated in every 

 part of the tropical world. In Hawaii, for instance, it is one 

 of the most important products. 



The Report of the Hawaii Agricultural Station, 1916, 

 contains some very interesting details of the work of the 

 Agricultural Department there on the cultivation of the 

 pine-apple, and the successful raising of seedlings from the 

 infrequent seeds occurring in the fruits. Seedlings were 

 obtained in 1913 and 1914, some of which have fruited in 

 1916. These seedlings have shown wide varieties. Some 

 are vigorous, while others are feeble. Some of the seedling 

 plants are gieen, while others show a brilliant red colouring. 

 In some the leaves are narrow, in others broad. Some of the 

 plants are smooth, while others are extremely spiny. 



These results have led the Agricultural Department of 

 Hawaii to believe that the collecting and breeding of varieties 

 of pine-apples at present grown in various parts of the tropics 

 might lead to the discovery of some which might do better 

 in Hawaii than those now grown. Accordingly eft'orts are 

 being made to obtain as large a collection of varieties as 

 possible from different ps.rts of the tropics. 



It is hoped to obtain new varieties of known parentage 

 by crossing established sorts, but as none of the introduced 

 varieties have as yet flowered in the Experiment Stations, 

 this has not been realized. The effort therefore to secure 

 new and more desirable varieties has been confined to grow- 

 ing seedlings from plants which, as has been said above, pro- 

 duce seeds in rare instances in local plantations. 



Through the co-operation of the large canneries in 

 Hawaii, several thousands of seeds were obtained in the 

 past year. The report, from which this article is drawn, says 

 that it is interesting to note how rarely these seeds occur. 

 The canneries dealing with millions of fruits may in some 

 seasons find no seeds. In the season 1915-16, in one count 

 of 63,000 fruits nine were found with seeds; in another count 

 of 48,000 fruits only four had seeds.* Vet, if the pineapple 

 seeds at all, it is so prolific that it is estimated that ihoie 



thirteen seeding fruits yielded 3,433 seeds. So that, 

 although seed bearing seems to be unusual, there was no 

 difficulty in obtaining the requisite number of seeds to make 

 experiments with in raising seedlings. 



It was found that in order to germinate and raise these 

 very tender plants several conditions were necessary: 

 perfect drainage, constant and uniform supply of moisture, 

 sufficient heat, and prevention of excessive algal growth on 

 the surface of the seed bed. The clever and successful way 

 in which these conditions have been fulfilled, with the result 

 of raising a vast number of seedlings, is another of the 

 triumphs of science as applied to agriculture by the 

 Americans. 



The following gives an account of the method pursued: — 



'An inch or more of broken rock is placed in the bottom 

 of the pot, and above this the pot is filled to within li inches 

 of the rim with a porous soil, on the top of which'a layer 

 of sand about J-inch thick is placed. This sand must 

 not be of coral origin, since the the lime in the coral is 

 extremely detrimental to young pine apple plants. Mould- 

 ing sand, such as is used by ironworkers, has been foind 

 satisfactory. On this sand the seeds are placed, thus s-curing 

 for them perfect drainage, while permitting the roots of the 

 seedlings to penetrate easily the soil beneath. The surface 

 of the sand is covered with coco-nut fibre dust mixed with 

 a little powdered charcoal, which retards the growth of algae, 

 and does not bake as does soil. The whole pot is then placed 

 in a larger pot, and the intervening space is packed with 

 moistened sphagnum moss. This prevents sudden changes 

 in moisture conditions in a climate where earthen pots dry 

 out (juickly on the sides as well as from the upper surface. 

 Water is never applied directly to the top of the soil, but 

 when necessary the inner pots are removed and placed in 

 water, which rises to the surface. 



'A closed glass box in the greenhouse has been found to 

 be advantageous, but not essential. The close atmosphere 

 and high temperature aid in the early germination of the seed. 

 Under such conditions pineapple seedlings begin to appear 

 about thirty-seven days after planting, while in the open, with 

 cool winter temperature, and without the close, damp, 

 atmosphere, sometimes two months or more is required for 

 germination. 



'When the seedlings begin to appear some shade is 

 necessary. Too intense light causes the plants to lose their 

 green colour and their vigour. A cheesecloth over the plants, 

 or a thin covering of whitewash on the glass of the box is 

 sufficient.' 



What the results of these seedling experiments with 

 pine-apples may ultimately be, it is impossible to predict. 

 Considering however the importance to the sugar industry 

 that is now attached to raising new varieties of sugar-cane 

 from .seedlings — quite a recent development— it may not be 

 too much to expect a considerable improvement, hardly perhaps 

 in llavour, but in hardiness and adaptability, of that queen of 

 fruits, the pine-apple. 



Some idea of the size and value of the citrus crop of 

 California, and of the immense benefits conferred on growers 

 by a well-organized association, is shown by the results 

 obtained by the California Fruit Growers' Exchange, the 

 largest and most successful of all the co-operative institutions 

 formed by the the fruit growers. During the year ending 

 August 31, 1916, the Exchange shipped 9,615,8.55 boxes of 

 oranges, 78,433 boxes of grape fruit, and 2,407,232 boxe.s of 

 kmons. The amount of money returned by the Exchange to 

 the shippers approximates 127,703,000, near:y $7,000,000 

 more than in any p:eceding year. (Statistical Report of 

 the California St.ite Board of Agricitlture, 1916.) 



