果树学报2024，Vol.41Issue(7)：1265-1274,10.DOI:10.13925/j.cnki.gsxb.20240041
沃柑混倍体新种质的鉴定及评价
Identification and evaluation of new mixoploid variants in Citrus reticula-ta'Orah'
摘要
Abstract
[Objective]Orah(Citrus reticulata)is an important late-maturing citrus variety.Previously,putative polyploid bud mutation materials were discovered in Orah.In this study,the material was iden-tified and evaluated in terms of ploidy,morphological characteristics,fruit quality and leaf microstruc-ture to provide a theoretical basis for its utilization.[Methods]Flow cytometry was used for ploidy identification,the paraffin sections were used for leaf microstructure identification,scanning electron microscopy was used for stomatal morphology,size and density identification,the morphological char-acteristics of leaves,flowers,seeds and fruits were compared,and the conventional methods were used to determine fruit quality parameters such as soluble solids content,titratable acid content,vitamin C content,edible rate and juice yield.[Results]Orah was diploid,while the variant material was a mixo-ploid of diploid and tetraploid(2x+4x),with a cell ratio of 2x∶4x=39.1∶60.9.There were differences in leaf morphology between the mixoploid and diploid.The mixoploid leaves were ovate with short acumi-nate tips and dark green color,while the diploid leaves were broad-lanceolate with gradually acuminate tips.The length,width,perimeter and area of the mixoploid leaves were 101.68 mm,54.29 mm,266.02 mm and 3 598.92 mm2,respectively,which were 14.75％,31.01％,19.38％and 46.09％higher than those of the diploid,respectively.The leaf shape index was 1.87,which was 12.61％lower.Both had bisexual flowers with similar petal numbers,petal colors,filament cohesion states and style states.The petal length and width of the mixoploid were 14.48 mm and 8.22 mm,respectively,which were signifi-cantly larger than those of the diploid,increasing by 34.32％and 49.18％,respectively.The seeds were both monoembryonic,and the mixoploid had higher seed weight,transverse diameter and longitudinal di-ameter than the diploid,increasing by 30.77％,8.12％and 26.64％,respectively.The single fruit weight of the mixoploid was 206.16 g,the longitudinal diameter of fruit was 63.37 mm,the transverse diameter was 77.90 mm,the fruit shape index was 0.81,the peel thickness was 4.26 mm,and the fruit firmness was 6.47 kg·cm-2,which were 29.67％,13.38％,8.57％,3.85％,38.31％and 16.37％higher than those of the diploid,respectively.However,the number of seeds per fruit was 8.2,which was 61.68％lower than that of the diploid.There were no significant differences in soluble solids content(15.10％)and ti-tratable acid content(0.58％)between the mixoploid and diploid.The edible rate decreased by 8.09％,the juice yield increased by 4.34％,and the vitamin C content increased by 39.70％.The cellular ar-rangement of the transverse section tissue structure of the mixoploid leaves was basically the same as that of the diploid.The thicknesses of the leaf,upper epidermis,lower epidermis,palisade tissue and spongy tissue were 310.96 μm,12.26 μm,72.89 μm and 227.94 μm,respectively,which were 19.75％,4.15％,10.10％,9.38％and 43.92％higher than those of the diploid,respectively.The stomatal length and density were 7.35 μm and 520.40 per mm2,respectively,which were 7.36％and 15.76％lower,re-spectively.The stomatal width was 3.33 μm,which was 5.09％higher.[Conclusion]In this study,a new mixoploid germplasm of Orah with diploid and tetraploid was identified.There were significant differences between the mixoploid and diploid in leaf,flower,seed,fruit morphology,fruit quality and leaf microstructure.Overall,the mixoploid showed larger and thicker leaves,increased petal length and width,increased seed weight,transverse and longitudinal diameters,but reduced number of seeds per fruit.The thicknesses of the leaf,upper and lower epidermis,palisade tissue and spongy tissue in-creased,while the stomatal length and density decreased and the stomatal width increased.Additionally,there were increases in single fruit weight,fruit transverse and longitudinal diameters and vitamin C content.This mixoploid can be used as a new type of single-embryo type of small-nucleus and large-fruit Orah,and can also be further used as a new germplasm resource for breeding program.关键词
沃柑/二倍体/混倍体/形态特征/果实品质/显微结构Key words
Orah(Citrus reticulata)/Diploid/Mixed ploidy/Morphological characteristics/Fruit quali-ty/Microstructure分类
农业科技引用本文复制引用
赵洪涛,王举兵,周双云,陈东奎,陈香玲,陆珍,李果果,解凯东,郑吉祥,梁增,刘要鑫,欧智涛,梁春..沃柑混倍体新种质的鉴定及评价[J].果树学报,2024,41(7):1265-1274,10.基金项目
广西重点研发计划(桂科AB23026033) （桂科AB23026033）
广西农业科学院基本科研业务专项(桂农科2023YM71) （桂农科2023YM71）
南宁市科技重大专项(20212140) （20212140）
广西柑橘创新团队桂南综合试验站(nycytxgxcxtd-2021-05-06) （nycytxgxcxtd-2021-05-06）
国家现代农业产业技术体系桂中南柑橘综合试验站(CARS-26) （CARS-26）
