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Zur Frage nichtbienengefährlicher Pflanzenschutzmittel 1
Author(s) -
Wahl O.
Publication year - 1976
Publication title -
zeitschrift für angewandte entomologie
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.795
H-Index - 60
eISSN - 1439-0418
pISSN - 0044-2240
DOI - 10.1111/j.1439-0418.1976.tb03367.x
Subject(s) - brood , pesticide , pollen , nectar , toxicology , biology , larva , fungicide , honey bees , bee pollen , ecology , horticulture
To the problem of pesticides not dangerous to bees Serious bee losses, occurring in Hessen (West‐Germany) after application of not injurious herbicides induced investigations on the bee's physiological conditions influencing the susceptibility to poison. It was shown that sensitivity to pesticides, to a large amount, depends on quantity and quality of the worker honeybee's pollen nutrition during the first days of life. Bees, sufficiently nourished with pollen are more resistent than undernourished bees of the same age and origin. According differences still occur with foragers at an advanced age. Intensive brood‐rearing increases the susceptibility to poison. The quality of larval food seems to be insignificant whereas the conditions of nectar flow and weather conditions during brood‐rearing time are highly effective. The influence of aging on the susceptibility to poison will be investigated. These results, for the time being, achieved by hormone herbicides were confirmed also for other pesticides, except for manganic fungicides. They have a stronger effect on bees well fed on proteins than on undernourished ones. By a high DL 50 of more than 1000–2000 μg/bee, part of the not injurious pesticides, especially organic fungicides are actually nontoxic for bees. It cannot be excluded that overdosages of other pesticides not dangerous to bees with a DL 50 under 25–50 μg are causing bee damages.