Genetic parameters of morpho-agronomic and physiological traits of crambe genotypes under drought conditions

ABSTRACT This work aims at evaluating and discriminating crambe genotypes regarding tolerance to water deficit by means of morpho-agronomic and physiological traits. The trial was carried out in a greenhouse under a randomized complete block design with four blocks, in a 2 x 8 factorial scheme, being two environments (with and without stress) and eight genotypes (FMS CR 1101, FMS CR 1106, FMS CR 1203, FMS CR 1305, FMS CR 1307, FMS CR 1312 and FMS CR 1326 and cultivar FMS Brilhante). The genotypes were evaluated according to physiological and morpho-agronomic traits. The significance of the mean squares was tested by the F test (P < 0.05) and the genetic parameters were estimated as ratio b between the genetic (CVg) and experimental (CVe) coefficients of variation, broad-sense heritability at genotypic mean level ( h ^ m 2), intraclass correlation (r) and selective accuracy (Ac). In general, water deficit did not cause severe physiological limitations to the plants. Plant height (PH), total dry mass (TDM) and grain yield (GY) were the traits that stood out for presenting the highest estimates of ratio b, h ^ m 2), CVg and r, revealing the possibility of genetic gains with the selection. Nevertheless, after evaluating the performance of genotypes in terms of physiological and morpho-agronomic traits, it was concluded that cultivar FMS Brilhante and inbred lines FMS CR 1326 and FMS CR 1106 had the most favorable traits for the selection, therefore, presenting potential for water deficit tolerance.

摘要 本研究旨在借助形态农艺性状（morpho-agronomic traits）与生理性状（physiological traits），对海甘蓝（crambe）各基因型的水分亏缺耐受性开展评价与区分。本试验于温室环境下开展，采用随机完全区组设计（randomized complete block design），设置4个区组，以2×8析因方案（factorial scheme）布设试验，共包含2个水分环境（施加水分胁迫与未施加水分胁迫）以及8份基因型材料：FMS CR 1101、FMS CR 1106、FMS CR 1203、FMS CR 1305、FMS CR 1307、FMS CR 1312、FMS CR 1326与品种FMS Brilhante。本研究针对生理性状与形态农艺性状对各基因型展开评价。采用F检验（F test，P<0.05）对均方的显著性进行检验，并估算以下遗传参数：遗传变异系数（genetic coefficients of variation, CVg）与试验变异系数（experimental coefficients of variation, CVe）的比值b、基因型均值水平的广义遗传力（h²_ₘ）、组内相关系数（intraclass correlation, r）以及选择准确性（selective accuracy, Ac）。总体而言，水分亏缺并未对植株造成严重的生理限制。株高（Plant height, PH）、总干物质质量（total dry mass, TDM）与籽粒产量（grain yield, GY）这几个性状表现突出，其比值b、广义遗传力（h²_ₘ）、遗传变异系数（CVg）以及组内相关系数（r）的估算值均为最高，表明通过对其进行选择可获得遗传增益。不过，在基于生理性状与形态农艺性状对各基因型的表现进行综合评价后，本研究得出如下结论：品种FMS Brilhante与自交系（inbred lines）FMS CR 1326、FMS CR 1106具备最适于选择的优良性状，因此具备水分亏缺耐受性的应用潜力。