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Principal component analyses of variation at 21 isozyme and 43 random amplified polymorphic DNA (RAPD) loci in eight cucumber (GY-14a, G421, H-19, WI 2757, and PIs 432860, 458845, and 183967) and seven melon [Top Mark (TM), Doublon, Green Flesh Honeydew (GFH), Juane Canari (JC), Freeman cucumber (FC), Snakemelon (SM), and PI 124111] cultigens were used to determine the use of these markers for assessing genetic variation among and within populations of each species (outgroup = Cucumis metuliferus). RAPD and isozyme marker variation was related to previous taxonomic classification and available pedigree information. Although dendrograms derived from cluster analyses using species' variation at marker loci were dissimilar, these disparities were consistent with differences in the pedigrees and/or other information (e.g., morphological) known about each accession and species. Elite U.S. processing cucumbers (G421, GY-14a, and H-19) shared distinctive biochemical affinities. Doublon was differentiated from TM, GFH, and JC. Doublon had biochemical affinities with FC, SM, and PI 124111.

Twenty specimens of the ‘gem-studded’, puffball, Lycoperdon perlatum Pers., sampled along Interstate Highway 86 East, north of Storrs, Connecticut, were found to be contaminated with cadmium and lead. Cadmium concentrations ranged from 0·00 to 5·34 ppm in different parts of the sporophores. Similarly, lead concentrations ranged from 0·00 to 80·98 ppm. Nickel was detected in only one sample at a concentration of 2·37 ppm.

Growth of Amanita muscaria, Cenococcum graniforme, Laccaria laccata, Pisolithus tinctorius, Rhizopogon roseolus, Suillus brevipes, S. grevellei, S. luteus, and Thelephora terrestris on Hagem Nutrient Agar as modified by Modess at 20°C for 28 days was inhibited by cadmium, lead, and nickel. All fungi were arrested by 350 μg cadmium per ml (ppm) or less. Lead arrested five species at 200 ppm or less; Cenococcum graniforme, L. laccata, and S. luteus were arrested at 2,000 ppm lead. Nickel arrested growth of six fungi at 20 ppm or less. Amanita muscaria, S. luteus, and L. laccata were arrested at 40, 175 and 225 ppm nickel, respectively. Metal concentrations that did not arrest delayed growth for 7–21 days after which the growth rate was comparable to the control.