LIST OF ILLUSTRATIONS 
Stripe disease of the tomato - - - - - - Frontispiece 
PAGE 
Fie. 1. Diagram illustrating an experiment on the relation of waterlogged 
soil conditions to chlorosis of the tomato - - - - 40 
Fias. 2 and 2a. Cdema of the geranium, showing swellings on the leaves 
and stem - - : - - - - - 42 
Fic. 8. (a) Hyphe; (b) thin-walled “‘summer” spores; (c) thick-walled 
resting spore ; (d) a pycnidium ; (e) a perithecium ; (f) ascus con- 
taining eight asco-spores - - - - - = 55 
Fic. 4. Tomato seedling attacked by ‘‘ damping off ”’ disease at (a) - 56 
Fie. 5. Hyphe of Rhizoctonia solani - - - - - 658 
Fia. 6. Phytophthora cryptogea: (1) Reproductive bodies—(a) conidium ; 
(b) zoospores. (2) Typical arrangement of conidia showing how 
one conidium after another is produced on the main axis—(a) empty 
conidium ; (b) young conidium - - - - - 60 
Fie. 7. Phytophthora foot rot of the tomato - - - - 63 
Fie. 8. Botrytis foot rot of the tomato - - - - - 64 
¥ie, 9. Botrytis sp. growing on tomato stem - - - - 64 
Fic. 10. agai foot rot of the a: (a) spores ; (b) diseased 
stem - - - . - - 65 
Fic. 11. Colletotrichum tabificwm on sears roots, = kyeiest. ee 
black sclerotia - - 69 
Fic. 12. Sclerotium disease of the tulip - - - - - 69 
Fic. 13. Botrytis disease of the tulip: (a) bulb showing black sclerotia ; 
(6) fungal growth on the bulb - - - - - 72 
Fie. 14. Verticillium wilt of the tomato. Old diseased tomato stem showing 
the fungal outgrowth at the base - - - - e — 5G 
Fie. 15. Verticillium wilt of the tomato: (a) wilted plant six weeks after 
inoculation with V. albo-atrum ; (6b) contro] plant - : - 5 
Fic. 16. This photograph shows the wilted plant in Fig. 15 after being sub- 
mitted to shade and an average temperature of 25° C. for thirty 
days. The wilted leaves have fallen off, but the plant has recovered 
and made good growth in the top - - - - - 179 
Fie. 17. Sweet pea, showing right-hand branch wilted as the result of 
inoculation with a pure culture of V. albo-atrum - 79 
Fig. 18. Spores of Fusarium vasinfectum : (a) microspores ; (b) sickle spores ; 
(c) chlamydospores - - - - - - 85 
Fie, 19. Sclerotinia sclerotiorum on the cucumber, showing typical sclerotia 88 
Fie, 20. Tomato stems showing ‘‘ cankers”’ made by Diplodina lycopersici 90 
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