Valiollah Rasoli - Ph.D. Member, Agricultural and Natural Resources Research Center of Qazvin, Qazvin, Iran
Ezatollah Farshadfar - Professor, Faculty of Agriculture, Razi University, Kermanshah, Iran
Jafar Ahmadi - Associated Professor, Imam Khomeini International University, Qazvin, Iran

Objective: Yield components and genetic contribution have the most important in final yield and breeding programs of crop plants. For this purpose, 20 varieties of grapevines with Russia origin were evaluated in Urmia and Takestan research station (under full irrigation and drought stress). Methods: Twenty grapevine genotypes were evaluated in Urmia and Takestan research station (under full irrigation and drought stress) inrandomized complete blocks design with three replications and three plants in each plot.Number of cluster per plant, Number of berry per cluster, berry weight and yield of eachplants were recorded. Compound and logarithmic analysis of variance, variance of genetic components and environmental interactions were presented by multiplicative three environmental and genotypic elements. Results: Results indicated that number ofcluster per plant had the highest genetic contribution in final yield and also had the most sensitivity and variation in different environments. Direct effect of number of cluster perplant in final yield was higher than other studied traits. V3 value was higher than V2 and V2 was higher than V1, therefore sequence of manifestation of yield components were number of cluster per plant, number of berry per cluster and berry weight, respectively. Environmental components of interactions were indicated that absolute value of r1 was higher than r2 and r3. Conclusion: These results indicated that number of cluster per plant has higher sensitivity than the other main yield components in different environments.

Path analysis ، Grapevine ، Logarithmic analysis ، Yield stability ،