Khalil Farghama, Rauf Saeed, Monneveux Philippe, Anwar Shoaib, Iqbal Zafar
Department of Plant Breeding & Genetics, University College of Agriculture, University of Sargodha , Pakistan.
Department of Plant Breeding & Genetics, University College of Agriculture, University of Sargodha, Pakistan; Plant Tissue Culture Lab, University College of Agriculture, University of Sargodha, Pakistan.
Breed Sci. 2016 Sep;66(4):463-470. doi: 10.1270/jsbbs.15068. Epub 2016 Jul 2.
Proline concentration has been often suggested as an indicator of osmotic stress. A better understanding of the genetics of this trait is however needed. In the present study, proline concentration has been assessed, together with root and stem growth, potassium, calcium and total soluble sugars concentration and stress injury symptoms, in seedlings of sunflower hybrids and their parents grown under control and osmotic conditions. Proline strongly accumulated with osmotic stress. Its concentration exhibited a large variation among genotypes and was higher in hybrids than in parental lines. A positive association was noted between proline concentration and osmotic adjustment that was reflected in a reduction of osmotic stress induced injury, as showed by the reduced number of calli in the hybrids with higher proline concentration. Broad and narrow sense heritability was higher under osmotic stress suggesting applying the selection in osmotic stress condition. In the control treatment, dominance effects explained most of the genetic variation for proline concentration while under osmotic stress both dominance and additive variance were high. The importance of dominance and additive effects suggested that several genomic regions are controlling this trait. Good general combiners, presumably carrying positive additive alleles affecting proline concentration, were identified.
脯氨酸浓度常被认为是渗透胁迫的一个指标。然而，需要更好地了解该性状的遗传学。在本研究中，对向日葵杂交种及其亲本在对照和渗透条件下生长的幼苗中的脯氨酸浓度、根和茎的生长、钾、钙和总可溶性糖浓度以及胁迫损伤症状进行了评估。脯氨酸在渗透胁迫下强烈积累。其浓度在基因型间表现出很大差异，且在杂交种中高于亲本系。脯氨酸浓度与渗透调节之间存在正相关，这反映在渗透胁迫诱导的损伤减少上，如脯氨酸浓度较高的杂交种中愈伤组织数量减少所示。广义和狭义遗传力在渗透胁迫下较高，表明在渗透胁迫条件下进行选择。在对照处理中，显性效应解释了脯氨酸浓度的大部分遗传变异，而在渗透胁迫下，显性和加性方差都很高。显性和加性效应的重要性表明，几个基因组区域在控制这一性状。确定了可能携带影响脯氨酸浓度的正向加性等位基因的优良一般配合力亲本。
