The dish pack method, which measures growth inhibition or promotion effects of volatile compounds on germinating seeds, was applied to measure the antifungal effects of 52 dried samples of spices and herbs against a soil-borne phytopathogenic fungus, Fusarium oxysporum. Black zira showed the strongest effect, followed by cumin and cardamom. Headspace sampling and gas chromatography-mass spectrometry analysis of black zira identified seven volatile compounds, gamma-terpinene, limonene, p-cymene, beta-pinene, alpha-pinene, cuminaldehyde, and myrcene. Among these, cuminaldehyde and p-cymene showed the strongest antifungal activities against F. oxysporum, suggesting roles in the antifungal activity of black zira. The same compounds also showed antifungal activities against another soil-borne phytopathogenic fungus, Verticillium dahliae, and foliar phytopathogenic fungi, Botrytis cinerea and Alternaria mali. The total activity calculated from the concentration of cuminaldehyde contained in black zira and its EC(50) against F. oxysporum demonstrated that cuminaldehyde is the main antifungal compound detected in black zira.

Insects and plants. E. vigintioctomaculataadults were collected at Natori City, Miyagi Prefecture and their progeny were reared at 24Ϯ1°C, 16L-8D photoregime. Leaves of potato, tomato (Lycopericon esculentum), and Lycium chinense were provided as food. These plants were cultivated in the field, except for the winter season in the greenhouse of the Faculty of Agriculture, Tohoku University.Bioassay. Feeding tests were conducted with a filter paper assay (Abe and Matsuda, 2000). Test extracts were dissolved in each extracted solvent (1 g fresh leaf equivalent/ml), and a square piece of AbstractA phytophagous lady beetle, Epilachna vigintioctomaculata, feeds mainly on potato (Solanum tuberosum) leaves. The methanol extracts of potato leaves showed feeding stimulative effects on the adult of the beetle. The feeding stimulants were isolated and identified as methyl linolenate from a lipid-soluble fraction, and glucose and fructose from an aqueous fraction. Although methyl linolenate alone was inactive, it acted synergistically with sugars. Methyl linolenate maximized the feeding activity of sugars at the concentration contained in the potato leaves. It is suggested that methyl linolenate plays an important role in the host selection of E. vigintioctomaculata.

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Dried parts of 75 medicinal plant species collected from different regions in Iran were assayed by the Dish Pack Method for volatile allelopathic activity, using Lactuca sativa (lettuce) as the test plant. The highest (60%) inhibition was observed for saffron (stigma of Crocus sativus), followed by Dracocephalum kotschyi, Solanum nigrum and Artemisia aucheri. Safranal was identified as the main chemical by Headspace Gas Chromatography-Mass Spectrometry (HS-GC-MS) analyses of saffron. Moreover, the EC 50 of safranal was evaluated as 1.2 µg/L (ppb). This is the first report on allelopathic activity of safranal as a bioactive compound identified from saffron.

The inhibitory activities of the leachates and volatiles from 53 plant species (spices and herbs) were evaluated against lettuce (Lactuca sativa “Great Lakes 366”) seedling growth using the sandwich and dish pack methods, respectively. With the sandwich method, parsley (Petroselinum sativum) showed the strongest inhibitory effect on lettuce radicle growth (77%), followed by tarragon (Artemisia dracunculus) (72%). However, caraway (Carum carvi), dill (Anethum graveolens) (seed), laurel (Laurus nobilis), rosemary (Rosmarinus officinalis), and sage (Salvia officinalis) were the most inhibitory species (100% inhibition of lettuce radicle and hypocotyl growth inhibition at all distance wells) in the dish pack method. Cardamom (Elettaria cardamomum) and thyme (Thymus vulgaris) also showed strong inhibitory activity (100% for radicle and hypocotyl growth inhibition at all 41 and 58 mm distance wells). The headspace sampling and gas chromatography-mass spectrometry (GC-MS) analysis identified the main inhibitory active compounds as carvone in caraway and dill (seeds), 1,8-cineole in laurel and cardamom, and borneol in thyme. Both camphor and 1,8-cineole were detected in rosemary and sage, and the total activity evaluation showed that camphor was the major inhibitory compound in rosemary, although both compounds played equal roles in sage.