4i8 



Minnesota Plant Diseases. 



Muskmelons, downy mildew of 



(Figs. 168, 169, 170), 334 



wilt of, 341 



Mustard family, club root of, 345 

 damping-ofif of seedlings, 



108, 382 



downy mildew of, 331 



Pythium debaryanum, 45 



white rust of, 112, j^o 



Mycelium, definition of, 7, 8 



development of, 18 



of food mold (Fig. i), 8 



of mushrooms, 11 



physiology of, 17 



Mycetozoa (Fig. 100), ig6, 197, 198 



Mycoplasm theory of rusts, 289 



Mycorrhiza of pufif-balls, 186 



Mycosis, 73 



Naked barley smut, 300 



Nectria cinnabarina, 



• 271, 272, 322, 323 



Needle-cast of pines, 138 



Nettles, sedge rust of, 391 



Nidulariineae, 186 



Nitrates, formation by bacteria, 195 



Nitrifying bacteria, 195 



Nitrogen-fixing bacteria, 195 



Nodule bacteria, 195 

 Nozzle, for mist-like sprays 



(Fig. 114), 231 

 for spraying apparatus (Fig. 



Ill), 228 



for spraying plants in rows, 230 



for spraying under sides of 



leaves (Fig. 112), 230 



Nuclear parasites, 66 



Nutrition of fungi, 10 



Nutritive method, expressed in 



structure, g 



Oak, Dcedalea on, 257 



dry rot of, 245 



false tinder fungus on, 250 



fatty Pholiota rot of (Fig. 



129), 263 



fungi on limbs, 139 



hairy pore-fungus, 259 



leaf blister of, 272 



Oak, 



leaf curl fungi on, 121 



partnership with fungus, 50 



partridge wood rot of, 242 



powdery mildew on, 125 



rust of milkweeds on, 280 



slime flux of, 271 



Stereum wood rot (Fig. 



117), 240 



sulphur fungus on (Fig. 



124), 252 



white-piped and yellow- 

 piped, 240 

 Oats, hot water treatment of, 157 

 loose smut of (Fig. 146), 



293, 294 

 rust (Fig. 141), 285 



smut of, 156, 157 



smut of, an accomplished 



parasite (Fig. 27), 59 



smut of, formalin treatment, 



221, 223 

 Oidium, 150 



chrysanthemi, j/p, 380 



Oil, fish, in resin bordeaux, 218 



Oil in resin prevention of rot, 240 

 Oils in ergot, 129 



Old man's beard, rust of, 386 



Olpidium brassicJE, 339, 340 



Onion, downy mildew of, 



smut of, 158, 320 



Oospora scabies (Fig. 164), 326 

 Orange leaf rust (see rust of 

 wheat). 



rust of raspberries, etc. (Fig. 

 160), 316, 317 



Orchard diseases, losses by, 202 



spraying, horizontal pump 



for (Fig. 108), 220 



trees, red knot on, 134 



trees, wounds and preven- 

 tion, 205 

 Orchards, diseases of, 347 

 Organisms causing disease, 189 

 Organs, destroyers of, 80 

 Ornamental plants, diseases of, 371 

 Oxalis, rust of corn, 292 

 Oyster fungus rot, 266 

 Palisade fungi (Fig. 81) 170 



gall disease of blueberry, 385 



wold, 171 



