Chromosomal Characterization of Tripidium arundinaceum Revealed by Oligo-FISH.

Fan Yu,Jin Chai,Jiayun Wu,Xueer Ding,Qiusong Wang,Xueting Li,Ruiting Yang,Zehuai Yu,Zuhu Deng,Xiping Yang

doi:10.3390/ijms22168539

Abstract

Sugarcane is of important economic value for producing sugar and bioethanol. Tripidium arundinaceum (old name: Erianthus arundinaceum) is an intergeneric wild species of sugarcane that has desirable resistance traits for improving sugarcane varieties. However, the scarcity of chromosome markers has hindered the cytogenetic study of T. arundinaceum. Here we applied maize chromosome painting probes (MCPs) to identify chromosomes in sorghum and T. arundinaceum using a repeated fluorescence in situ hybridization (FISH) system. Sequential FISH revealed that these MCPs can be used as reliable chromosome markers for T. arundinaceum, even though T. arundinaceum has diverged from maize over 18 MYs (million years). Using these MCPs, we identified T. arundinaceum chromosomes based on their sequence similarity compared to sorghum and labeled them 1 through 10. Then, the karyotype of T. arundinaceum was established by multiple oligo-FISH. Furthermore, FISH results revealed that 5S rDNA and 35S rDNA are localized on chromosomes 5 and 6, respectively, in T. arundinaceum. Altogether, these results represent an essential step for further cytogenetic research of T. arundinaceum in sugarcane breeding.

Highlights

Sucrose is produced from two major crops, sugarcane (Saccharum spp.) and sugar beet (Beta vulgaris)
Based on the oligo-fluorescence in situ hybridization (FISH) results, for the first time, we reported that maize chromosome painting probes (MCPs) can distinctly detect chromosomes 1–10 of T. arundinaceum
The results showed that the number of oligos that align to the sorghum genome ranged from 277 to 27,169 (Table 1), which implied that these MCPs will produce various signals on the chromosomes of sorghum

Summary

Introduction

Sucrose is produced from two major crops, sugarcane (Saccharum spp.) and sugar beet (Beta vulgaris). Accounts for the vast majority of global sugar production and provides feedstocks for bio-energy production. Interspecific hybridization is a powerful way to enhance resistance and provides unexpected benefits in increasing yield and improving ratooning ability and adaptability [1]. S. spontaneum (2n = 40–128), which for more than a century has played a major role in sugarcane breeding, has been widely applied to improve the resistance of sugarcane cultivars. E. arundinaceum (2n = 60, x = 10) is used for sugarcane breeding due its high biomass productivity, superior ratooning ability, and exceptional adaptability to biotic and abiotic stresses [2]. Many studies have reported cytogenetic research on T. arundinaceum, especially on the chromosome inheritance of the hybrids between sugarcane and T. arundinaceum [4,5,6]. Basic cytogenetic information such as the karyotype, and the precise chromosome contribution of T. arundinaceus in interspecific hybridization, could not be addressed due to lack of effective cytogenetic markers to identify the individual chromosomes

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Discussion

Conclusion