Determination of outcrossing rates in some cowpea (Vigna sinensis L.) ecotypes in Aydin

In this study, it was aimed to determine the outcrossing distances and rate of some local cowpea ecotypes. At the beginning two ecotypes, which is collected from this region before, were used (no:15, black eyed white seeded maternal parent and KK, black seeded paternal parent). At the repetition of the study another local ecotype was included (no:19 as second paternal parent, brown seeded). Morphological markers were used to determine the outcrossing distances of the landraces. Some traits, which are defined in IBPGR?s cowpea descriptor, were used for this purpose. At the first year of the study (2005), to obtain information about the direction and the distance of outcrossing, the landraces were planted in a special arrangement and allowed for outcrossing. At the second year of the study (2006), the seeds obtained from the plants of the first step were grown and observed as the second generation. At the following two years (2007-2008) the study was repeated. The data subjected to cluster analysis and PCA by using NTSYSpc 2.2 version. The plants which were in the same cluster with paternal ecotypes, accepted as outcrossed. At the first study (2005), the outcrossing distance at north, south, east and west was 23m, 32m, 18m and 21m respectively; at the repetation of the study (2007) the outcrossing distance at north, south, east and west was 8m, 5m, 4m and 17m respectively. It is supposed that the differences of outcrossing distance between the two years is based on the ecological (especially the temperature and humidity) factors and the differences between the activities of the pollinator insects in that conditions. Although it is supposed to obtain natural outcrossing ratios by using inheritance of seed-colour character, reliable results could not obtain because of the complication of seed colour inheritance.