Comparisons were made of some physical and chemical characteristics of lemons (Citrus limon L.) imported into western Europe from 11 countries of origin. Statistically significant differences in quality characteristics were found. Fruit from Chile, Cyprus, Israel, and the United States was the most uniform in yellow coloring. Lemons from Argentina, Israel, South Africa, and Uruguay tended to be rounder than more elongated fruit from Spain and Turkey. Thickest peels were found in Chilean, Greek, Italian, and Spanish fruit, and thinnest peels in South African and Uruguayan fruit. Regardless of origin, the largest fruit had the thickest peel and contained a lower percentage of juice. Israeli lemons had the highest percentage of juice and Argentine, Chilean, and Spanish fruit, the lowest. Total soluble solids (TSS) concentration was highest in juice of fruit from Cyprus and Turkey and lowest in fruit from South Africa and Spain. Total acid (TA) concentration was highest in Turkish fruit and lowest in Italian, South African, and Spanish fruit. Smaller fruit from most countries had higher concentrations of ascorbic acid than larger fruit. Chilean lemons had the highest, and Turkish and U.S. lemons the lowest, ascorbic acid levels.
Strains of Penicillium digitatum (Sacc.) and P. italicum (Wehmer) resistant to thiabendazole and benomyl were isolated from decaying citrus fruits obtained from the Rotterdam, Netherlands, terminal market and originating from 18 countries. Significantly more Penicillium sp isolates with resistance to thiabendazole and benomyl were collected from grapefruit and lemons than from oranges. Significantly more isolates of P. digitatum than P. italicum grew on agar plates with 4, 10, or 40 ppm thiabendazole. A greater percentage of P. digitatum than P. italicum isolates grew on 4 and 10 ppm benomyl-agar plates, but a greater percentage of P. italicum than P. digitatum isolates grew on 40 and 80 ppm benomyl-agar plates. Both species were more resistant to thiabendazole than to benomyl, and often showed cross-resistance to the fungicides. Resistant Penicillium sp isolates produced larger colonies on 4 and 10 ppm thiabendazole and 40 and 80 ppm benomyl.