Page 187 - 《广西植物》2025年第10期
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10 期                 张晓宁等: 马尾松花粉超低温保存的生理响应及转录组分析                                          1 9 1 7

                 Abstract: In order to preliminary analyze the physiological response and related metabolic mechanism of Pinus
                 massoniana pollen to cryopreservationꎬ the pollen of P. massonianaꎬ as the research objectꎬ was cryopreserved in liquid
                 nitrogen (LN)ꎬ at -196 ℃. The physiological indexes related to reactive oxygen species (ROS) were assessed during
                 the freezing process ( CK: before freezingꎻ LD: after freezing with liquid nitrogenꎻ HD: after freezing and
                 thawing). Transcriptome sequencing was also performed using the next generation sequencing( NGS) technology and
                            TM
                 Illumina HiSeq  6000 platform. The results were as follows: (1) The optimal water content for cryopreservation was
                 3.96% (fresh weight basis). At this water contentꎬ the P. massoniana pollen was directly immersed in liquid nitrogenꎬ
                 where it was stored for at least 48 hꎬ then was removed from liquid nitrogen and transferred to room temperature for 20
                 minutes to achieve thawing. The survival rate was 73.80% after freezing and thawingꎬ compared with 78.54% before
                 freezing. (2) During the cryopreservation processꎬ significant differences were observed in the four indexes of superoxide
                 dismutase ( SOD)ꎬ glutathione ( GSH)ꎬ ascorbate peroxidase ( APX)ꎬ and the ability to inhibit hydroxyl free
                 radicals. (3) A total of 65.60 Gb clean data were obtained from transcriptome sequencingꎬ with 38 505 genes mapped to
                 the reference genome (47.84%)ꎻ the number of differentially expressed genes (DEGs) in comparisons of CK vs LDꎬ CK
                 vs HDꎬ and LD vs HD were 232ꎬ 268ꎬ and 218ꎬ respectively. In the current studyꎬ Gene Ontology (GO) and Kyoto
                 Encyclopedia of Genes and Genomes ( KEGG) analyses showed that GO terms such as response to stimulus and
                 antioxidant activityꎻ KEGG pathways such as plant hormone signal transductionꎬ MAPK signaling pathwayꎬ starch and
                 sucrose metabolismꎬ fructose and mannose metabolismꎬ and peroxisome pathways were significantly enriched. Ten genes
                 in these pathways that may be closely related to protection and repair during cryopreservation were further screened. All
                 the results indicate that the freezing and thawing process which is related to oxidative stress induced by ROS affects the
                 cryopreservation of P. massoniana pollenꎬ as well as the water content. The results of this study help to improve the
                 efficient preservation and utilization of the pollen of Pinus massonianaꎬ and also provide a reference for further analysis
                 of the molecular mechanism of cryopreservation damage.
                 Key words: Pinus massonianaꎬ pollenꎬ cryopreservationꎬ physiologyꎬ transcriptome




                马尾松(Pinus massoniana) 是我国南方三大速                 2021)ꎮ 轻木花粉在液氮中保存 40 d 后ꎬ花粉的活
            生树种之一ꎬ种植面积居我国乔木之首ꎬ具有重要                             力为 72%ꎬ效果好于其他低温保存方式( 席会鹏
            的经 济 价 值 ( 秦 国 峰 和 周 志 春ꎬ 2012ꎻ 杨 章 旗ꎬ             等ꎬ2023)ꎮ 丝瓜、大豆花粉经超低温保存后在萌
            2012)ꎬ但由于松材线虫危害ꎬ种质资源安全正受                           发率、受精率、结实率方面与新鲜花粉没有明显差
            到严重威胁ꎮ 花粉包含个体发育所需要的全部基                             异(Jia et al.ꎬ 2022ꎻ Nagar et al.ꎬ2023)ꎮ 黑加仑花
            因ꎬ遗传信息极其丰富ꎬ是种质保存、交换、人工辅                            粉在液氮中保存 12 个月ꎬ其活力甚至较保存前提
            助授粉及杂交育种的重要材料ꎮ 自然状态下ꎬ马                             高 了 0. 9% ( Tikhonova et al.ꎬ 2021 )ꎮ 徐 进 等
            尾松花粉的寿命只有 1 个月ꎬ很难解决植物杂交                            (1998)指出ꎬ若在干燥的前提下将马尾松花粉保
            育种中的花期不遇及地理隔离等问题ꎬ而一般的                              存在-60 ℃ 以下的超低温冰箱里或液氮中ꎬ可使
            花粉保存技术如常温干燥和 4 ℃ 低温干燥最多贮                           其生活力保存更长时间ꎮ 遗憾的是ꎬ目前并未见
            存 11 个月ꎬ-20 ℃ 低温干燥可保存 25 个月ꎬ但生                     关于马尾松花粉超低温保存的研究报道ꎮ
            活力 均 降 到 10% 以 下 ( 徐 进 等ꎬ 1998ꎻ 谭 健 晖ꎬ                 尽管理论上利用超低温技术可以实现材料的
            2011)ꎮ 因此ꎬ开展经济、高效的花粉长期保存技                          长期保存ꎬ但是实际操作过程中有许多因素会影
            术研究对于保障马尾松种质资源安全及高效利用                              响冻存效果ꎬ甚至造成材料死亡ꎮ 除材料本身的
            具有重要意义ꎮ                                            特性以 外ꎬ 花 粉 含 水 量、 活 性 氧 ( reactive oxygen
                 超低温保存通常指将生物材料采用一定技术                           speciesꎬROS)诱导的氧化应激反应和细胞程序性
            存入液氮中保存ꎬ使用时采取一定方法使其恢复                              死亡是细胞损伤的主要原因( Len et al.ꎬ2019ꎻ 张
            生长ꎮ 该方法能够实现花粉的长期保存并提高育                             晓宁 等ꎬ 2020aꎬ bꎻ 任 瑞 芬 等ꎬ 2022ꎻ Ren et al.ꎬ
            种 效 率 ( Dinato et al.ꎬ 2020ꎻ Gowthami et al.ꎬ      2020aꎬb)ꎮ ROS 是有氧代谢的副产物ꎬ可以清除
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