Ting Wang, Fu Xu, Zhoutao Wang, Qibin Wu, Wei Cheng, Youxiong Que, Liping Xu

Int J Mol Science; 2023 Feb 1; 24(3):2793. doi: 10.3390/ijms24032793.

Abstract

The processes of sugarcane tillering and ratooning, which directly affect the yield of plant cane and ratoon, are of vital importance to the population establishment and the effective stalk number per unit area. In the present study, the phenotypic data of 285 F₁ progenies from a cross of sugarcane varieties YT93-159 × ROC22 were collected in eight environments, which consisted of plant cane and ratoon cultivated in three different ecological sites. The broad sense heritability (H²) of the tillering and the ratoon sprouting was 0.64 and 0.63, respectively, indicating that they were middle to middle-high heritable traits, and there is a significantly positive correlation between the two traits. Furthermore, a total of 26 quantitative trait loci (QTLs) related to the tillering ability and 11 QTLs associated with the ratooning ability were mapped on two high-quality genetic maps derived from a 100K SNP chip, and their phenotypic variance explained (PVE) ranged from 4.27-25.70% and 6.20-13.54%, respectively. Among them, four consistent QTLs of qPCTR-R9, qPCTR-Y28, qPCTR-Y60/qRSR-Y60 and PCTR-Y8-1/qRSR-Y8 were mapped in two environments, of which, qPCTR-Y8-1/qRSR-Y8 had the PVEs of 11.90% in the plant cane and 7.88% in the ratoon. Furthermore, a total of 25 candidate genes were identified in the interval of the above four consistent QTLs and four major QTLs of qPCTR-Y8-1, qPCTR-Y8-2, qRSR-R51 and qRSR-Y43-2, with the PVEs from 11.73-25.70%. All these genes were associated with tillering, including eight transcription factors (TFs), while 15 of them were associated with ratooning, of which there were five TFs. These QTLs and genes can provide a scientific reference for genetic improvement of tillering and ratooning traits in sugarcane.

See https://pubmed.ncbi.nlm.nih.gov/36769121/

Figure 5

The distribution of the detected QTLs related to the plant crop tillering rate (A) and the ratoon sprouting rate (B) on sugarcane genetic linkage maps of the parents ROC22 and YT-93-159, respectively. LG, linkage group. Different colors in the figure represent different environments. Pink and orange represent the tillering rate of the plant cane in Dehong and Baise in 2020, respectively; yellow represents the tillering rate of the plant cane in Zhanjiang in 2021; pale green, blue and purple represent the first ratoon sprouting rate in Dehong, Baise and Zhanjiang in 2021, respectively; deep green and red represent the second ratoon sprouting rate in Dehong and Baise in 2022, respectively.