The isonucleus inbred lines study has been initiated from the demand of clarifying if the cytoplasm source has a positive or negative influence on the corn ears, plants, grain traits and some maize cultural features (RACZ et al, 2011). Studies conducted on different male cytoplasm sterile inbred lines have highlighted differences between the various cytoplasm sources inbred lines and also differences in regarding the obtained single crosses behavior (GRACEN and collab., 1979; HAŞ and collab., 1999). The research has been conducted in the experimental field provided by the Maize Breeding laboratory  from Agricultural Research and Development Station Turda in 2009. There have been studied the following maize ear traits for isonucleus inbred lines: ear weight (g), kernel weight per ear (g), kernel rows per ear, kernel number per raw, ear diameter (cm), rachides diameter (cm), thousand kernel weight (g), kernel depth and the kernel yield per ear. The transfer has been realized through 10 cross-breeding procedures with the nucleus donor inbred line in 1992-2004 time period. After that, the isonucleus inbred lines maintenance has been realized through self-pollination and SIB pollination. Through the 10 times cross-breeding procedures with the nucleus donor line we can appreciate that the nucleus has been transferred 99,9% on the new cytoplasm (Chicinaş et al, 2009). For all the 11 studied traits there have been determined significances of the corresponding variance for cytoplasm and „cytoplasm x testers” interaction. The cytoplasm has had a significant influence in the hereditary transfer in the case of ear length in four out of five clusters from the studied isonucleus lines and the „cytoplasm x testers” interaction has been significant for all the five tested clusters. The thousand kernel weight has been statistically significant differenced due to cytoplasm influence in four of the five tested clusters and the „cytoplasm x testers” interaction in one single case. The mean kernel number/ear has been influenced by the cytoplasm source in four of the five tested groups and the „cytoplasm x testers” interaction has had significant figures in four tested clusters. Although the study assumption was that different cytoplasm sources are influencing the kernel depth, this hypothesis hasn’t been confirmed.

cytoplasm, single crosses, maize, ear traits

Presentation: oral