Endophytic fungi from Vitis vinifera L. isolated in Canary Islands and ...

Genetic analysis for plant yield in winter wheatCiulca S. 1 * , Ciulca Adriana 1 , Madosa E. 1 , Velicevici Giancarla 11 Banat‟s University of Agricultural Sciences and Veterinary Medicine Timisoara, Faculty ofHorticulture and Forestry*Corresponding author. Email: c_i_sorin@yahoo.comAbstract Grain yield per plant is one of the main components of yieldpotential; therefore it essentially determines the yield level. Because of thecomplexity for this trait it is difficult to improve yield through breedingespecially in the early generations. Generation mean analysis is a quantitativegenetic method be able to estimate additive, dominance and epistatic effects.The present study aims to obtain useful information about gene action for sixwinter wheat crosses, and to establish the opportunities of recovery in wheatbreeding.The positive values of heterosis relative to mid and to better parents indicatedthat dominance direction was toward the best respective parent. The crossRomulus x G.K.Gobe recorded significantly higher intensity of heterosis toother combinations. The dominance effects showed higher values than theadditive effects, indicating that dominance gene effects play the major role incontrolling the genetic variation of plant yield. A high contribution in geneticdeterminism of this trait has the epistatic effect, especially the additive xdominant effectKey wordswinter wheat, plant yield,gene effectsDiallel analysis of variance - covariance regression for spikelength in six-row winter barleyCiulca S. 1 * , Ciulca Adriana 1 , Madosa E. 1 , Velicevici Giancarla 11 Banat‟s University of Agricultural Sciences and Veterinary Medicine Timisoara, Faculty ofHorticulture and Forestry*Corresponding author. Email: c_i_sorin@yahoo.comAbstract The choice of an efficient breeding procedure depends to alarge extent on the knowledge of the genetic system controlling the characterto be selected. The spike length holds great value for yield improvement inbarley. High values of spike length cause a yield increase only if they areassociated with high spike density. The present research were conducted toascertain the nature of gene action involved in the determinism of spike lengthfor a set of six doubled haploids lines of six-row winter barley.The studied parental forms in terms of spike length submitted a higherproportion of dominant alleles and a nearly symmetrical distribution of positiveand negative alleles. In both generations, the overdominance direction wasassociated with an increase in spike length. A high proportion of recessiveand negative alleles have been reported in DH 19-1 line, respectively a largeproportion of dominant and negative alleles submitted the DH 26-2 and DH20-4 lines, while the other lines showed a relative instability during the twogenerations. Because the genetic system that controls the spike length fourboth generations is mainly additive, selection can play a great role in breedingmethod of that trait.Key wordssix-row barley, spike length,diallel analysis