Fig. 4

Association of lower leaf angle with mitogenome diversity during maize breeding. A–D Manhattan plot (left) and mitogenome haplotypes (right) showing association (with a red arrow and P value) of lower leaf angle (LAL) of LAL_BLUP (best linear unbiased predictor) (A), LAL_LF2016 (B), LAL_JL2017 (C), and LAL_LF2017 (D) with the haplotypes TT, NN, TG, and GG, respectively, in the position of 184,809. The LAL were collected in the city of Langfang in Hebei province in 2016 (LF2016) and 2017 (LF2017), Ledong County in Hainan province in 2016 (HN2016), and Gongzhuling in Jilin province in 2017 (JL2017) in China. The arrow in (A) indicates the best linear unbiased predictor value for data of LAL phenotyped across four environments in 2 consecutive years. Different letters indicate statistical significance of P < 0.05 (Student’s t-test). E Proportion of mitogenome haplotypes at 184,809 (upper panel) with the lower leaf angle trait which is one of four listed in A–D (lower panel) among breeding lines in different stages and regions. Public-USA and Ex-PVP indicate public inbred lines in the US and elite commercial lines with expired Plant Variety Protection Act Certificates mostly released after 2003, respectively. F Proportion of mitogenome haplotypes in Z. parviglumis (upper panel) and landraces (lower panel)