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Acta Agronomica Sinica ›› 2024, Vol. 50 ›› Issue (6): 1384-1393.doi: 10.3724/SP.J.1006.2024.34159

• CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS • Previous Articles     Next Articles

Creating cold resistant germplasm of potato using Solanum boliviense

LIU Yuan-Yuan1(), DONG Jian-Ke1, YING Jing-Wen1, MEI Wen-Xiang1, CHENG Gang2, GUO Jing-Jing1, JIAO Wen-Biao3,*(), SONG Bo-Tao1,*()   

  1. 1National Key Laboratory for Germplasm Innovation and Utilization of Horticultural Crops / Key Laboratory of Potato Biology and Biotechnology, Ministry of Agriculture and Rural Affairs / Huazhong Agricultural University, Wuhan 430070, Hubei, China
    2Institute of Detection for Agricultural Products of Ezhou, Ezhou 436099, Hubei, China
    3College of Informatics, Huazhong Agricultural University, Wuhan 430070, Hubei, China
  • Received:2023-10-02 Accepted:2024-01-31 Online:2024-06-12 Published:2024-02-21
  • Contact: * E-mail: songbotao@mail.hzau.edu.cn;E-mail: jiao@mail.hzau.edu.cn
  • Supported by:
    National Key Research and Development Program of China(2022YFD1100201);China Agriculture Research System of MOF and MARA(Potato, CARS-09)

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Abstract:

Potato cultivars are not tolerant to low temperatures and frost, which directly affects the growth and development of plants and tubers, thus affecting potato yield. Wild potato species, such as S. boliviense, have abundant resources for cold frost resistance, which are important resources for improving cultivated potato varieties. Based on cold resistance identification of different S. boliviense strains, we screened and obtained the excellent strain BLV29-2 (S. boliviense) with comprehensive traits. It was then crossed and backcrossed with the diploid cultivar ED25, resulting in interspecific hybrids with stronger cold resistance. Inter-specific hybrid strains that had shown significant improvement in cold tolerance were treated with recycled colchicine. Cold tolerance and agronomic traits were assessed in some of the strains, and the results showed that all the doubled materials had significant increases in plant height, pollen grain diameter, and individual potato weight. Most of the materials showed there was no significant change in cold tolerance before and after doubling, but significantly improved compared to the cultivated species control. By crossing the treated strain T-FT073-4-7 with the superior tetraploid cultivar Huashu 13, we observed segregation of cold resistance in the offspring, with the 47% of the materials showing a preference towards the maternal parent T-FT073-4-7 and significantly higher cold resistance compared to the paternal cultivar. Through further field evaluations of agronomic traits, we identified selected breeding materials with the improved overall traits and the significantly enhanced cold resistance. This study successfully introduced the excellent cold resistance of the diploid wild species S. boliviense into the tetraploid cultivar, thus addressing the deficiency of the existing cultivar in terms of low-temperature sensitivity. These findings provide an important foundation for the selection and further improvement of cold-resistant genetic breeding materials.

Key words: potato, cold resistance, agronomic traits, chromosome doubling, genetic improvement

Table 1

A total of 25 lines of 10 accessions of the wild species S. boliviense"

株系
Line		 材料
Accession		 株系
Line		 材料
Accession		 株系
Line		 材料
Accession
BLV29-1 PI 472806 BLV33-1 PI 498362 BLV36-3 PI 545999
BLV29-2 PI 472806 BLV33-2 PI 498362 BLV37-1 PI 546000
BLV29-3 PI 472806 BLV33-3 PI 498362 BLV37-2 PI 546000
BLV30-1 PI 473131 BLV34-1 PI 498383 BLV37-3 PI 546000
BLV30-2 PI 473131 BLV34-2 PI 498383 BLV38-1 PI 546010
BLV31-1 PI 473134 BLV34-3 PI 498383 BLV38-2 PI 546010
BLV32-1 PI 473135 BLV35-2 PI 500031 BLV38-3 PI 546010
BLV32-2 PI 473135 BLV36-1 PI 545999
BLV32-3 PI 473135 BLV36-2 PI 545999

Fig. 1

Identification of cold resistance and agronomic traits of S. boliviense FT is freezing tolerance, and CA is cold acclimated freezing tolerance. A: the identification of cold resistance of S. boliviense; B: the identification of plant height of S. boliviense; C: the identification of pollen viability of S. boliviense; D: BLV29-2 pollens; E: BLV37-2 pollens; F: BLV29-2 plant; G: BLV33-3 plant. Values are means ± SDs (n = 3). Bar: 20 μm."

Fig. 2

Identification of FT051 agronomic traits A: BLV29-2 plant; B: ED25 plant; C: FT051-2 plant; D: FT051-3 plant; E: BLV29-2 flowers; F: ED25 flowers; G: FT051-3 flowers; H: FT051-9 flowers."

Fig. 3

Identification of cold resistance of FT073 FT is direct cold resistance and CA is acclimated cold resistance. White and black columns indicate before and after cold resistance, respectively. Values are means ± SDs (n = 3)."

Fig. 4

Identification of FT073 agronomic traits A: FT073-19 plant; B: FT073 plant height; C: FT073 stem thick; D: FT073 main stem number; E: FT073-16 plant; F: FT073 stem color; G: FT073 leaf shape index; H: FT073 leaf area. Values are means±SDs (n = 3)."

Fig. 5

Identification of ploidy of treatment materials A-F are chromosome count ploidy identification. A: AC142; B: E3; C: FT073-15; D~F: T-FT073-15. Bar: 5 μm."

Fig. 6

Identification of cold resistance before and after material doubling FT is direct cold resistance, and CA is acclimated cold resistance. Black and gray columns indicate the cold resistance of the material before and after doubling, respectively. Values are means ± SDs (n = 3). Asterisks indicate significant difference between double before and after by using Student’s t-test (*: P < 0.05)."

Fig. 7

Identification of agronomic traits before and after material doubling A: FT073-15 plant; B: T-FT073-15-1 plant; C: FT073-15 flower; D: T-FT073-15-1 flower; E: FT073-15 pollens; F: T-FT073-15-1 pollens; G: FT073-15 tubers; H: T-FT073-15-1 tubers. Values are means ± SDs (n = 3)."

Fig. 8

Phenotypes of FT123 after frost A: T-FT073-4-7; B: Huashu 13; C: FT123-2; D: FT123-6; E: FT123-16; F: FT123-25; G: FT123-33; H: FT123-47."

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