676 



INDEX 



--tree-to-tree 123,204,208 

 Varietal blends or mixtures, see 



Multiline varieties 

 Varieties, see Cultivars 

 Vegetative propagation by rooting, 

 grafting, etc. 20,241,244-46, 

 255,258,265,288,304,413-24,546, 

 583,612,627-28,631 

 Venturia inaequalis (Cke.) Wint . , 



apple scab 3,10,18 

 Vertical resistance, see Resistance, 



differential 

 Vertifolia-effect 27,56,529-30, 



621 

 Vesicles, see Infection structures 

 Victorin, the Victoria blight 

 fHelminthosporium victoriae) 

 toxin 552 

 Viburnum, viburnums 154-55 

 --cotonifolium D.Don, smoketree 



viburnum 154 

 Virulence and avirulence 5-6,8-11, 

 13,18,26-27,31,34-35,39,422,440, 

 453,533,562,564-65 

 Virulence, differential 18,50,56, 



70,300,302,454-55 

 Viruses 95,568,572,599-603 

 Vole, red-backed, see Clethrionomys 

 rufocanus bedfordiae (Thomas) 



Wound periderms 387,431,439,452, 



465,467-68,527 

 Wulfenia amharstiana Wall., wulfenia 



154 



Xanthomonas malvacearum (E .F. Smith) 

 Daws., blackarm of cotton or 

 cotton blight 55 



X-rays 7,9-10,552 



Yield, timber, forage, grain, etc. 

 see Variation, genetic 



Zea mays L. , maize or corn, see 

 Hybrid lines, corn 11,36,294, 

 567-68,572-74,579-80,582,617- 

 22,624-25,630-31,633,639 



--x Sorghum hybrids 639 



Zymograms 474 



Warning systems, disease, see 



Disease 

 Water content 90 

 Water films and infection, see 



Infection, climatic optima 

 Water- and snowshed protection, 



avalanche and flood control 99, 

 101,106-07,186,215-16,219,228, 

 647 

 Wax plugs, stomatal 431,437,462-63 

 Weevils, see Pissodes and Hylobius 



spp. 

 Western white pine, see Pinus 



monticola 

 Wheat, see Triticum spp. 

 White pines 



--general, see also Pinus spp. 3, 

 9,11,18,19-24,99-123,271-79, 

 289-90,294,569,645-56 

 --botanical range 274-75 

 White pine blister rust, see 



Cronartium ribicola 

 Wide crossing 231,633,638-39 

 Wood quality 584,592 



