OGM18-07 ISTA Method Validation Reports Page 152/164 Approved ECOM Decision 18025 Validation study for the addition of Cicer arietinum (Desi type) as a species to which the conductivity test for seed vigour can be applied to support Rules proposal C.15.1 Mohammad Khajeh-Hosseini 1 , Carina Gallo 2 , Marie-Helene Wagner 3 and Hulya Ilbi 4 1 Department of Crop Science, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran. agr844@gmail.com or saleh@ferdowsi.um.ac.ir 2 National Institute of Agricultural Research, Oliveros Experimental Station, Oliveros, Argentina 3 Station Nationale d’Essais de Semences (SNES), GEVES, Angers, France 4 Ege University, Faculty of Agriculture, Department of Horticulture, Bornova-Izmir, Turkey Abstract The conductivity test identified differences in field emergence of 11 seed lots of the Desi type of chickpea (Cicer arietinum). Six of these seed lots, all having a laboratory germination of more than 85%, were tested by four laboratories using the electrical conductivity test, as described in the ISTA Rules (ISTA 2015). All laboratories consistently identified the same significant differences in the seed lot conductivity and the results were repeatable within laboratories and reproducible between laboratories. This provides evidence in support of the addition of Cicer arietinum (Desi type), to the ISTA Rules as a species for which the conductivity test can be applied. Introduction The conductivity test is validated in the ISTA Rules as a test that can be applied to species of Pisum sativum, Phaseolus vulgaris, Glycine max, Cicer arietinum (Kabuli type) and Raphanus sativus (ISTA, 2018). This test is based on the leakage of solutes that occurs from all seeds that are soaked in water. These solutes include sugars, amino acids and most importantly for the test, electrolytes. Thus the incidence of leakage can be detected by measurement of the electrical conductivity (EC) of the seed soak-water. The test was developed following the observation of the correlation between solute leakage and field emergence in wrinkled-seeded vining peas (Pisum sativum). Low leakage and therefore low conductivity was associated with seeds that emerged well, that is seeds with high vigour; whereas low vigour seeds with poor emergence had high levels of leakage and conductivity (Matthews and Whitbread, 1968). The conductivity test has also been used as an indicator of field emergence in field beans (Vicia faba, Hegarty, 1977), Phaseolus beans (Powell et al., 1986), soybean (Oliveria et al., 1984; Yaklich et al., 1984) and long bean (Vigna sesquipedalis; Abdullah et al., 1991). Leakage has also been related to emergence in the light-coloured, larger seeded Kabuli type chickpea (Cicer arietinum) (Khajeh-Hosseini et al., 2007; Khajeh-Hosseini and Rezazadeh, 2011) leading to the validated method and inclusion of the Kabuli type chickpea as a species to which the EC test can be applied (ISTA,2014). There is however another, distinctly different and well recognised type of chickpea, the Desi type which has smaller, coloured seeds (Smartt and Simmonds,