OECD 208 Seedling Emergence and Seedling Growth Test.pdf

TG/Administrators/Jukka/Plant tests/208sept03_draft 1/19 DRAFT DOCUMENT September 2003 OECD GUIDELINE FOR THE TESTING OF CHEMICALS PROPOSAL FOR UPDATING GUIDELINE 208 Terrestrial Plant Test: 208: Seedling Emergence and Seedling Growth Test INTRODUCTION 1. OECD Guidelines for the Testing of Chemicals are periodically reviewed in the light of scientific progress and current regulatory procedures. This updated guideline is designed to assess potential effects of substances on seedling emergence and growth. As such it does not cover chronic effects or effects on reproduction (i.e. seed set, flower formation, fruit maturation). Conditions of exposure and properties of the substance to be tested must be considered to ensure that appropriate test methods and test substance levels are used (e.g. when testing metals/metal compounds the effects of pH and associated counter ions should be considered)(1). This guideline does not address plants exposed to vapours of chemicals. The guideline is applicable to the testing of both general chemicals and crop protection products (also known as plant protection products or pesticides). It is based upon existing methods (2) (3) (4) (5) (6) (7) (8). Other references pertinent to plant testing were also considered (9) (10) (11). Definitions used are given in Annex 1. PRINCIPLE OF THE TEST 2. The test assesses effects on seedling emergence and early growth of higher plants following exposure to the test substance in the soil (or other suitable matrix). Seeds are placed in contact with soil treated with the test substance and evaluated for effects following 14 to 21 days after 50% emergence of the seedlings in the control group. Endpoints measured are visual assessment of seedling emergence, biomass (fresh or dry shoot weight, or shoot height) and visual detrimental effects (chlorosis, mortality, plant development abnormalities, etc.). Measurements are made at least weekly or more often when recordi