Identification of genotypes possessing GA responsive reduced height genes in bread wheat (Triticum aestivum)

Abstract

The present study was conducted during years 2017-18 and 2018-19 involving 60 wheat genotypes including advance lines and released varieties. Based on the coleoptile length, these were categorised for coleoptile length as short (2.5-4.5 cm), medium (4.6-6.5 cm) and long (6.6-9 cm) respectively. Small and medium coleoptile length genotypes had comparable plant height (100.07cm and 99.29 cm, respectively) whereas, longer coleoptile genotypes were in general taller (103.78cm) numerically and for each class, the speed of germination was almost similar.A set of linked SSRs markers was used to screen the genotypes for molecular characterization based on GA responsive genes. In wheat, longer coleoptile length with reduced height is primarily controlled by GA responsive reduced height genes like Rht8, Rht12 etc., therefore, the material was screened to identify genotypes possessing GA responsive reduced height genes with available molecular markers. Molecular screening for Rht genes revealed five Rht8 positive genotypes having longer coleoptile length and good seedling vigour. Thus, Rht8 genes had positive effect on coleoptile length and had no detrimental effect on root length of seedling and provided better field emergence in field. Hence, these genotypes can be used for the development of variety for dryland agriculture and underconservation agriculture practices.

Keywords

• Coleoptile length
• Dryland agriculture
• Reduced height genes
• SSR markers
• Seedling traits