Effects of pesticides in seed-coats on the germination and protection of Eucalyptus regnans seed.  F. G. Neumann and F. Y. Kassaby.  November 1984.  16 pp. (unpubl.)

SUMMARY

Laboratory tests are described on the effects of non-pesticidal adhesives and kaolin bulking agent, and of 13 commercial pesticide products, on the germination and seedling quality of Eucalyptus regnans F. Muell. (mountain ash). The effectiveness of some of these pesticides as seed protectants on a low-elevation ashbed site in the Victorian Central Highlands is also reported.

In the laboratory, mucilage and kaolin, either alone or in combination, moderately reduced germinative capacity, though not germinative energy or seedling quality. About two-thirds of the pesticides were moderately or severely phytotoxic when applied with kaolin, or in undiluted form, to seed testas. Fungicides containing carbaryl, copper, or high concentrations of benomyl, carboxin, mancozeb or thiram were especially phytotoxic. Symptoms of poisoning were: reduced or zero germinative capacity and/or poor quality germinants, often without normal tap roots or secondary roots.

Commercial R & T SPECIAL TOMATO DUST^† (a mixture of 2% DDT, 0.5% lindane, 5% mancozeb and 40% sulphur) diluted 1:1 by weight with kaolin and applied to testas with mucilage, showed some potential as an effective seed protectant in the field for periods up to two months during winter. Further evaluation of this product, of alternative adhesives, bulking agents and pesticides, is required before an effective protective seed-coat can be prescribed for E. regnans seed.

^†Registered Trade Name. Use of trade names is for the information and convenience of the reader. Such use does not constitute official endorsement or approval by the Forests Commission of any product to the exclusion of others that may be equally suitable.

Also published:

Neumann, F.G. and Kassaby, F Y. (1986)  Effects of pesticides in seed-coats on the germination and protection of Eucalyptus regnans seed.  Aust. For. Res. 16 (1): 37-50.