Phenotypic variability and correlation estimates for traits of Burkina Faso’ sweet grain sorghum genotypes

Abstract

Sweet grain sorghum [Sorghum bicolor (L.) Moench] is a neglected crop mainly grown for its sweet grains in the pasty form. Although its taste is the main character of interest, knowledge of protein related content of the grain, especially when linked to its value for infant porridge appears equally important. The objective of this study was to evaluate the status of crude protein content of pasty grains and to determine genetic correlations between morphological and biochemical traits among sweet grain of sorghum genotypes in Burkina Faso. Eight sweet grain sorghum cultivars (BTO2, BZI1, KBZ4, PBO5, PGO3, SBR7, SPI2, STO4) were evaluated through 13 morphological and two biochemical variables. Crude protein content of these genotypes was also compared with the composition of two controls of sweet stalk sorghum (ETS) and ordinary grain sorghum or common sorghum (EBS). The analysis of variance revealed variability within sweet grain sorghum accessions, mainly on the biochemical traits (crude protein and water content) and two morphological traits (peduncle and panicle lengths), which discriminated significantly in the thresholds of 1 and 5%, respectively. In addition, sweet grain sorghum had low crude protein content compared to other types of sorghum, except, two genotypes of sweet grain sorghum (BZI1 and STO4) which recorded higher protein content compared to the common sorghum. An important and negative correlation was noted between sowing-flowering cycle and protein content.