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Gardening for Amateurs 



mosaic disease as surely as a sterilised needle 

 from an infected plant thrust into healthy 

 tissue gives rise to it, provided the aphides 

 have recently feasted on infected plants. 

 This proves that the disease is contagious, 

 although all efforts to discover the organism 

 have so far failed. 



Remedies. The mosaic disease is often 

 confounded with streak, but the yellow 

 mottling and dotting in the leaves is quite 

 distinct from the browning of the tissue 

 caused by Bacillus lathyri, and it is not so 

 injurious in its effects. Plants infected with 

 streak very seldom, if ever, recover from the 

 malady, but those having the mosaic disease 

 fairly demonstrated may generally be re- 

 stored by applications of iron sulphate, J oz. 

 per gallon of soot water, the soot water being 

 made by putting 1 peck of soot into a sack, 

 placing in a tub containing 30 gallons of 

 water, and allowing to stand for a week. 

 Apply once a week, on both sides of the row 

 of plants, at the rate of 1J gallons per yard 

 run of row, 3 quarts on each side. 



Mould. Mould is caused by a parasitic 

 fungus, and is marked by yellowing of the 

 leaves and blotches on the stem, which 

 become brown and bear a delicate white out- 

 growth from the innate mycelium. This 

 disease affects the seed vessels and seeds, and 

 may go over as latent mycelium in the in- 

 tegument of the latter ; hence the seedlings 

 collapse in their germinating stage or when 

 only a few inches in height. 



Remedies. Soaking the suspected seeds 

 overnight in water at a temperature of 135, 

 then allowing to cool, has been attended 

 with good results. Similar claim is made for 

 disinfecting seed by soaking in a solution 

 of permanganate of potash, 1 oz. to 1 quart 

 of water. Dusting with powdered quicklime 

 and sulphur, using twice as much lime as 

 sulphur, checks the spread of the mould. 

 The dusting should be repeated at intervals 

 of three or four days. All affected haulm 

 should be burned when pulled up. 



Anthracnose. This disease is charac- 

 terised at the outset by whitish spots on 

 the leaves, involving the greater part or the 

 whole ; infected leaves become brittle and 

 soon drop. Sometimes the disease is mani- 

 fested in a wilting or dying of the tops of the 

 growths, which become whitish and brittle 



and readily break off. At other times the 

 fungus works downwards and involves the 

 whole branch. At the time of blossoming 

 the parasite attacks the peduncles at the 

 point of union with the buds, producing 

 " bud-drop," the bud hanging wilted from 

 the peduncle ; or both flower bud and 

 peduncle may be attacked, when both dry 

 up but do not fall off. Infected pods lose 

 their green colour, become shrivelled, and 

 soon show salmon-coloured patches. 



The fungus responsible for Anthracnose 

 also causes a bitter rot of Apple, and goes 

 back and forth from the Apple to the Sweet 

 Pea, in each case reproducing the typical 

 symptoms of the disease. It spreads rapidly, 

 often destroying the entire crop ; sometimes 

 it attacks young seedlings, especially those 

 raised under glass. The disease outdoors 

 usually starts about midsummer, when the 

 plants are in bloom and at their prime, and 

 it is then that bitter rot disease of the Apple 

 makes it appearance in the orchard. The 

 fungus tides over winter on diseased limbs 

 and mummied fruits of diseased Apples. 

 It is also carried over in the diseased 

 pods and seeds of the Sweet Pea, and on 

 diseased parts that have fallen and are left 

 on the soil. 



Remedies. Possibly Anthracnose may be 

 prevented by (1) disinfecting seed before 

 sowing, (2) spraying with half-strength 

 Bordeaux Mixture in mid-June and a fort- 

 night later, (3) burning all diseased haulm 

 and deeply trenching the ground where the 

 plants have grown. 



Root Rot. The fungus Thielavia basi- 

 cola, often referred to as the cause of streak, 

 is responsible for this disease. Plants affected 

 with Thielavia, however, have little or no 

 root system, since it is destroyed by the 

 fungus as soon as the roots appear. The 

 fungus sometimes works up the stem to a 

 distance of 2 or 3 inches above ground, but 

 never to the extent of invading the entire 

 stem. The effect is to cause a yellowing 

 of the leaves and then collapse from below, 

 with stoppage of growth and ultimate 

 destruction, this being aided by other fungi. 

 Plants infected with Thielavia basicola, 

 however, do not quickly die ; they may 

 linger on for a long time sometimes through- 

 out the entire growing season. The infected 



