Lecture II — 35 — • Occurrence of Mycorrhizae 



dolus) by RuGGiERi (1937). In Cacao in Trinidad, mycorrhizae 

 also occur (Pyke, 1935; Laycock, 1945), although not invariably. 

 Sabet (1939) describes mycorrhizae for cotton (Gossypium), and 

 TuNSTALL (1940) for Thea. 



For other plants, Heath and Luckwill (1938) report my- 

 corrhizae in Potentilla and several other heather-land plants ; while 

 Malan (1938) studied mycorrhizae of alpine legumes (finding 

 them phycomycetous). For Ericaceae, Barrows (1936, 1941) 

 studied Epigaea, and Freisleben (1933, 1934) particularly Vac- 

 cinium; Gordon (1937), Rhododendron; Bain (1937), after study- 

 ing Oxycoccus, comes to the conclusion that there is no obligate 

 symbiosis while Rayner & Levisohn (1940) contradict him; 

 MoLLiARD (1937) after studying Calluna, concludes that mycor- 

 rhizae are not essential. For potato (Solamim), Costantin (1935, 

 1936) and Joseph (1935) present data. Kurbis (1937) and 

 Kelley (1943) have described mycorrhizae for Fraxinus; 

 ScHiMMLER (1937) for 12 spp. of Gentiana. 



Since Monocotyls are not woody, less interest can be expected 

 in them. It is true that there are some monocotyledonous trees which are 

 reported mycorrhizal, — the palms Phoenix and Livistona, the screw- 

 palm, Pandanus, and the banana "tree", Musa. But most Mono- 

 cotyls are herbs, and many are aquatic plants in which no mycor- 

 rhizae are found, as Typha (Asai) ; Alisma (Asai) ; Calla palus- 

 tris; Acorus, 2 spp. ; and 10 spp. of Juncus which, however, pro- 

 duce root swellings that do contain a fungus according to Magnus. 

 No mycorrhizae are reported for the Cyperaceae; vis. 2 spp. of 

 Cyperus, 3 spp. of Eriophorum, and 14 spp. of Carex; but numer- 

 ous species of grasses are reported mycorrhizal. For the Gramin- 

 eae, Asai (1934) reported 23 species mycorrhizal and 4 not my- 

 corrhizal, the latter all hygrophylls; while 58 spp. were reported 

 mycorrhizal by other observers. The latest researches on grasses are 

 by BiRAGHi (1936) on cereals, and Neill (1940) on Lolium. Of 

 the aroids, Arisaema is mycorrhizal (Lohman. 1927), while Magrou 

 (1937, 1939) used Arum for isolation of the endophyte. 



The Liliales seem richly mycorrhizal : Veratrum in the Melan- 

 thaceae, Allium, Lilium, Tulipa, Erythronimn, Ornithogalum, 

 Muscari, Hemerocallis, Yucca, Fritillaria, Scilla and Aloe in the 

 Liliaceae; Asparagus, Smilicina, Maianthemum, Uvidaria, Poly- 

 gonatum, and Convallaria in the Convallariaceae; and Trillium in 

 the Trilliaceae. Oddly, there is no report for Smilax. Then Nar- 

 cissus, Galanthus, Leucojum (Stahl) and Agave (2 spp.) of the 



