Estimation of genetic parameters and selection for rooting capacity in peach

Abstract One of the most important criteria in the improvement of rootstocks is easiness of propagation. The objective of the present study was to verify the existence of genetic variability and the possibility of gains with selection in the rooting capacity among peach genotypes. Seventy-seven genotypes of peach belonging to five F3 families were evaluated. Rooting percentage (RP), number of roots per cutting (NR) and mean root length (RL) were evaluated. Genetic values were estimated. The nineteen genotypes with the lowest rank summation index were selected to estimate the genetic gains. The variables RP, NR and RL had progeny mean heritabilities of 0.53, 0.60 and 0.83, respectively. Of the individuals selected, 89.5% belonged to the 713 (Talismã x Adafuel) family. The estimation of the genetic and phenotypic parameters show the possibility of success by selecting superior genotypes, with gains of 9.09, 17.47 and 24% for RP, NR and RL, respectively.

摘要 砧木育种改良的核心评价标准之一为繁殖便利性。本研究旨在验证桃基因型生根能力的遗传变异情况，以及通过选择获得遗传增益的可行性。本研究共评估了隶属于5个F3家系的77份桃基因型材料，测定指标包括生根率（Rooting Percentage, RP）、单插穗生根数（Number of Roots per Cutting, NR）以及平均根长（Mean Root Length, RL）。研究人员对各性状的遗传值进行了估算，随后选取秩和指数最低的19份基因型材料以估算遗传增益。结果显示，入选的基因型中89.5%隶属于713（Talismã × Adafuel）家系。生根率、单插穗生根数及平均根长的家系平均遗传力分别为0.53、0.60和0.83。遗传与表型参数的估算结果表明，通过筛选优良基因型可实现育种目标，生根率、单插穗生根数及平均根长的遗传增益分别为9.09%、17.47%和24%。