BOTANICAL VIEW OF ANTIBIOTICS — ^JONES 377 



Ringworm infections, including athlete's foot, which are actually 

 caused by fungi and not by worms, are a pesky annoyance. They are 

 a fringe or filamentous benefit of modern bargain-basement existence. 

 A remarkable remedy against the fungi of ringworm has recently 

 come upon the market in the antibiotic griseofulvin, which incongru- 

 ously must be admmistered orally. This antibiotic was among the 

 very first to be discovered. It was tried only topically and found 

 wanting as a deterrent to ringworm, and promptly disregarded. Re- 

 cently, a chance oral administration revealed its extreme effectiveness. 

 It is readily absorbed by the gastrointestmal tract and exerts its fung- 

 istatic action in the newly growing skin, hair, and nails which, with 

 shedding or cuttmg, are replaced by normal structures free of fungi. 

 Dr. Jolm Ehrlich of the Parke, Davis and Company reports: "It is 

 the only major advance in the therapy of infection caused by dermato- 

 phytes [skin fungi] in at least a half centuiy." The antibiotic griseo- 

 fulvin, is named from the mold which produces it, Penicillium 

 griseofulvin. 



Flowering plants and conifers are parasitized by fungi which may 

 cause gTeat destruction; witness the loss of our elms from a fungus 

 which is transmitted by a bark beetle. Any plant has countless fun- 

 gus spores on its exposed surfaces, and it is not unusual to have local- 

 ized networks of fungus filaments within the healthy tissues. One of 

 the well-established, symbiotic, natural associations in plants is the 

 mycorrhiza (mycor-, fungi, and -rhiza, root) in which particular 

 species of fungi form a mantle over the young, active roots and may 

 penetrate into the cells. Mycorrhiza occur commonly among conifers, 

 heaths, and orchids but probably are of wide occurrence. These as- 

 sociations are apparently of a symbiotic nature : the fungus acquires 

 a food source, and the higher plant derives vitamins and a more ade- 

 quate mineral supply, as the filaments of the fmigus spread beyond the 

 roots into leaf mold, where their presence is detected by the f ruitmg 

 bodies, mushrooms or toadstools, which they produce seasonally. In 

 orchids, the filaments of the fungus grow throughout the plant from 

 root to topmost leaf ; in fact, the developing seeds within the flowers 

 are inoculated with the fungus and carry it away when they are shed, 

 tucked within their cells. Conifers cultivated in a new area may not 

 succeed unless the appropriate fungus is introduced into the soil. 



Where trees in a forest are manifestly diseased one would do well 

 to suspect the growing conditions, rather than the entrance of a new 

 virulent pathogen. Something is usually awry ecologically or phys- 

 iologically, such as the water supply or mineral nutrition. These 

 conditions bring on a lowering of disease resistance. 



Under cultivation, the entire situation may be so unnatural for 

 plants that diseases become a major problem to the grower. Approx- 

 imately 30,000 important plant diseases have been studied by botanists. 



