Accurate exploration of citrus tetraploid based on morphological characteristics of seedling fibrous roots

doi:10.16178/j.issn.0528-9017.20240725

Abstract

Abstract:

Citrus tetraploid resources can provide new germplasm for triploid hybrid parents and stock genetic improvement. In this study, a simple method was established to accurately explore citrus tetraploid, which involves densely sowing diploid citrus seeds in a vermiculite substrate to germinate and form seedlings. After the seedlings have fully developed their fibrous roots, the plants with significantly short and thick fibrous roots are observed with the naked eye as tetraploid citrus. By using this method, we screened 8, 6, 8, 7, 4 and 1 putative tetraploids respectively from 616, 354, 476, 536, 648 and 289 seedlings of Citrus aurantium cv. Goutoucheng, Citrus aurantium cv. Changshanhuyou, Citrus paradisi Macf., Citrus sinensis×Poncirus trifoliata, Poncirus trifoliata Raf., Citrus reticulata Blanco cv. Succosa. All the tetraploids were confirmed by flow cytometry, and the screening accuracy rate of morphological characteristics reached 100%. The tetraploid population detection rates of the above six varieties were 1.30%, 1.69%, 1.68%, 1.30%, 0.62% and 0.35%, respectively. This method has a high detection rate and is easy to operate, which achieves 100% screening accuracy and completes the work of tetraploid breeding without the condition of ploidy identification instrument.

Key words: citrus, fibrous root morphology, tetraploid, accurate exploration

CLC Number:

S666.1

WANG Ping, KE Fuzhi. Accurate exploration of citrus tetraploid based on morphological characteristics of seedling fibrous roots[J]. Journal of Zhejiang Agricultural Sciences, 2026, 67(1): 62-66.

Figures/Tables 4

References 19

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幼苗类型	叶片数	株高/cm	叶长/cm	叶宽/cm	叶形指数	主根粗/cm	主根长/ cm	主根尖粗/cm	须根数	第一须根粗/cm	第一须根长/cm	第一须根尖粗/cm	最长须根长/cm
二倍体	5.33±0.58 a	5.60±0.35 a	3.17±0.06 a	1.33±0.12 a	2.39±0.24 a	0.17±0.01 a	14.10±1.15 a	0.05±0.02 a	22.33±2.08 a	0.04±0.01 b	6.33±0.65 a	0.04±0.01 b	10.97±1.79 a
四倍体	3.67±0.58 b	4.67±0.15 b	2.50±0.10 b	1.43±0.15 a	1.75±0.11 b	0.19±0.01 a	8.17±0.76 b	0.09±0.02 a	18.00±2.00 a	0.07±0.02 a	3.23±1.25 b	0.07±0.01 a	4.77±1.12 b

幼苗类型	叶片数	株高/cm	叶长/cm	叶宽/cm	叶形指数	主根粗/cm	主根长/ cm	主根尖粗/cm	须根数	第一须根粗/cm	第一须根长/cm	第一须根尖粗/cm	最长须根长/cm
二倍体	5.33±0.58 a	5.60±0.35 a	3.17±0.06 a	1.33±0.12 a	2.39±0.24 a	0.17±0.01 a	14.10±1.15 a	0.05±0.02 a	22.33±2.08 a	0.04±0.01 b	6.33±0.65 a	0.04±0.01 b	10.97±1.79 a
四倍体	3.67±0.58 b	4.67±0.15 b	2.50±0.10 b	1.43±0.15 a	1.75±0.11 b	0.19±0.01 a	8.17±0.76 b	0.09±0.02 a	18.00±2.00 a	0.07±0.02 a	3.23±1.25 b	0.07±0.01 a	4.77±1.12 b