[in Japanese]

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Both second stage larvae of M. incognita hatched in soil (SHL) and in water (WHL) were stored at 10°C and 25°C in a volcanic ash soil with a moisture content of 65%. After given periods, those larvae were recovered by applying the double-layer centrifu-gal-flotation method. The larval suspensions recovered were divided into two equal parts and half of each part was placed on filters made of a thin layer of absorbent cotton with a sheet of Japanese paper set in Baermann funnels for 72 hr at room temperature to count the numbers of living larvae. The other halves were observed under a compound micro-scope at magnifications of 60-150 and the amount of food reserves was estimated from the area of the dark parts in the intestines.
Under storage at 25°C, the number of living larvae in SHL gradually decreased and 44% of the initial number remained until 90 days. Food reserves were not consumed appreciably. On the other hand, both numbers of larvae and food reserves in WHL showed a rapid decrease during the first 10 day period, but a slow one thereafter. Numbers of larvae after 10 and 90 days were 40% and 10% of the initial values, respectively. Under storage at 10°C, numbers of larvae and food reserves decreased slightly regardless of the hatching conditions.
Based on the results obtained at 25°C, it is considered that some factors related to hatching may influence the survival of the nematode larvae, or that the existence of some microhabitats in soil allows for a longer survival.

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Scales of Unaspis yanonesis remained on citrus leaves for 2 weeks on the average and for 58 weeks maximum after the emergence of the parasitoid, Aphvtis yanonensis. Analysis of the persistence curve of the scales revealed that 12% of the scales disappeared each month and that it took 21 weeks for 50% of the scales to disappear. Thus, the percentage parasitism of the parasitoid estimated from samples containing such scales would give rise to an overestimation of the values.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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Laboratory experiments were carried out to estimate the prey consumption of Feltiella sp., a predator of the kanzawa spider mite, Tetranychus kanzawai KISHIDA. The prey consumption increased with the growth of the larvae. The maximum number of preys consumed by old larvae was about 7 adult female mites per day. There was no significant difference in the prey consumption at temperatures ranging from 15 to 25°C. The number of mites consumed slightly decreased when the temperature decreased below 10°C However, old larvae consumed about 4 adult female mites per day at 5°C. The total number of preys consumed throughout the larval period was the largest at 15°C, when the larval period was longer than of higher temperatures. The predator consumed about 80 eggs per day at temperatures ranging between 15 and 20°C. In the tea fields, the population density of this predator was higher in winter than in other seasons. It is reasonable to assume that the predatory activity of this predator is high at relatively low temperatures.

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The present report deals with the results of a wild bee survey made in the central part of Fukuoka Prefecture, Kyushu, during the bee season in 1984 and 1985, in order to obtain some basic information about the faunal makeup and phenology. The total sample consisted of 26 genera, 104 species and 1857 individuals. Halictidae ranked first, followed by Andrenidae, Anthophoridae and Megachilidae. The faunal makeup in the present area is similar to that observed in Kagoshima Prefecture, South Kochi and Kibi (Wakayama Pref.).

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