Pathogenicity of three Phytophthora spp. causing late seedling rot of Quercus ilex ssp. ballota

Within a research project on quality of plants for forestation of agricultural lands, we studied the aetiology of a late seedling rot affecting holm oak (Quercus ilex ssp. ballota) in two forest nurseries in southern Spain. Major disease symptoms were foliage wilting and necrosis of feeder roots. Phytophthora cinnamomi, Phytophthora cryptogea and Phytophthora drechsleri were isolated from necrotic roots of holm oaks. Selected isolates of the three Phytophthora species were pathogenic to Quercus ilex ssp. ballota and Quercus suber seedlings in artificial inoculations. Soil flooding conditions were essential for infection and root rot development. There was no host specificity among the species, the isolates of P. cinnamomi being the most virulent in all inoculated plants. In these inoculations, Q. ilex ssp. ballota plants were more susceptible than those of Q. suber. This work is the first report of P. cinnamomi, P. drechsleri and P. cryptogea affecting Q. ilex ssp. ballota in forest nurseries.     

设施栽培果树病虫害种类与发生特点

对桃、杏、樱桃设施栽培下病虫害调查的结果显示，全区设施果树病虫(螨)害共27种，其中虫(螨)害16种，分属4目12科；病害11种，分属9目9科(属)。主要病虫(螨)害12种(病害6种，虫害5种，螨类1种)。经对果树主要病虫(螨)害在设施条件下的发生危害规律观察，总结出了设施果树病虫害发生特点。     

Buchbesprechungen

Ohne Zusammenfassung     

Buchbesprechungen

Ohne Zusammenfassung     

Makroarthropoden im Grünland des Innsbrucker Mittelgebirges (Nordtirol, Österreich)

Macroarthropods from a montane meadow near Innsbruck (Austria)Composition and variation in dominance of macro-arthropods inhabiting a montane meadow near Innsbruck (Rinn 900 m) are described from collections by pitfall traps and by water traps from March-October 1975. Abundance is highest near the ground for most groups, only Diptera showing maximum activity at the surface level of vegetaion. Isopoda, Chilopoda, Carabidae are moving strictly upon the soil surface. Daily activity of locomotion is strongly asymmetric betweenend of June to mid-August, being about 120% higher at daytime than at night.

---

---

Institut für Zoologie, Universitätsstr. 4, A-6020 Innsbruck.     

Der Einfluß von Fluorverbindungeii auf den Chlorophyll a+b-Gehalt von Pappelblättern im Freiland bei verschiedener Belastung1

The effect of different concentrations of fluorine on the content of chlorophylls a and b in poplar leaves. The concentrations of the chlorophylls a and b and of the fluoride ions in poplar leaves were measured regularly from May to September 1974. The concentration of F increased steadily whereas the concentration of the chlorophylls decreased by 30% compared to first appearance of the leaves. The content of F- to that of chlorophyll a and b cannot be correlated.