沼生栎种子失水过程中水分时空迁移规律

doi:10.11707/j.1001-7488.LYKX20220124

摘要/Abstract

摘要：

目的: 探究沼生栎种子失水过程中水分的动态迁移规律，为其安全运输、贮藏提供理论依据。方法: 采用自然干燥法降低种子的含水量，利用核磁共振成像技术分析失水过程中种子内部水分的迁移路径，并结合信噪比定量分析失水过程中种子各部位水分的散失情况。结果: 1）高场核磁共振成像及信噪比结果表明：新鲜种子中胚根区域、子叶中心部位水分含量较高，子叶外围区域水分相对较少；不同组织、不同部位子叶及不同部位种皮的信噪比均有差异。2）含水量降至30.0%时，胚根区域水分大幅下降，且胚根尖端失水速率最快，子叶外围水分也有所减少，而子叶中心部位水分变化不明显，失水最慢；种皮各部位水分散失速率也不同；含水量继续降至25.0%时，种子发芽率开始显著下降，此时胚根区域的水分已近乎不见，信噪比再次大幅下降，胚根下方很大一部分子叶开始变暗，3个种皮部位的信噪比均降至很低，其中合点端信噪比降幅最大，且该部位由于失水而出现皱缩现象；含水量降至10.0%时，子叶皱缩明显，只有子叶中心部位及其下方一小部分区域还存在少量水分。结论: 沼生栎种子的重要储水部位为胚根区域和子叶中心位置，失水过程中胚根尖端水分下降最快，子叶中心部位失水最慢，胚根区域水分的流失是影响种子质量下降的重要原因。

关键词: 沼生栎, 顽拗型种子, 失水, 核磁共振成像技术, 水分迁移

Abstract:

Objective: Quercus palustris is mainly propagated by seeds, but its seeds are sensitive to dehydration, belonging to recalcitrant seeds. Consequently, water loss is an influential factor affecting its seed storage and transportation. This study aims to explore the dynamic movement pattern of water during the water loss process in Q. palustris seeds, in order to provide a theoretical basis for safe transportation and storage of Q. palustris seeds. Method: In this study, the seed water content was reduced by the natural drying method. Magnetic Resonance Imaging (MRI) technology was utilized to analyze the movement path of water in seeds during dehydration and combined with Signal-to-Noise ratio (SNR) to quantitatively analyze the water loss in each part of seeds during the water loss process. Result: 1) The results of high-field MRI and SNR analysis showed that the water content in the radicle region and central part of cotyledons of fresh Q. palustris seeds was higher, while the water content in peripheral parts of cotyledons was relatively lower. The SNR of different tissues, cotyledons and seed coats were different. 2) When the water content of seeds decreased to 30.0%, water content in the radicle region dropped significantly, with the water loss rate of the radicle being the fastest. Meanwhile, the water loss rate of cotyledon periphery also decreased, while the water of cotyledon center did not change significantly, and its water loss rate was the slowest. Additionally, the water loss rate in different parts of seed coat was also different. When the water content continued to drop to 25.0%, the germination percentage of seeds decreased significantly. At this time, the water in radicle region was almost invisible, with a large part of cotyledon below the radicle beginning to turn dark. As the SNR of radicle region fell sharply again, the SNR of three seed coat parts was reduced to a very low level, among which, the SNR of seed chalaza decreased the most, and the chalaza shrank due to water loss. When water content was reduced to 10.0%, the cotyledon shrank obviously, with only a small amount of water remaining in the central part of cotyledon and a small part below it. Conclusion: The important water storage sites of Q. palustris seeds are the radicle region and the cotyledon center. During the water loss process, the water loss rate of radicle is the fastest, while the water loss rate of the cotyledon center is the slowest. The water loss in radicle is a critical factor causing seed quality to decline.

Key words: Quercus palustris seeds, recalcitrant seeds, desiccation, magnetic resonance imaging (MRI), water movement

中图分类号:

S718.43

袁鸣,朱铭玮,解志军,康真,李淑娴. 沼生栎种子失水过程中水分时空迁移规律[J]. 林业科学, 2024, 60(6): 44-49.

Ming Yuan,Mingwei Zhu,Zhijun Xie,Zhen Kang,Shuxian Li. Temporal and Spatial Water Movement Pattern during the Water Loss Process in Quercus palustris Seeds[J]. Scientia Silvae Sinicae, 2024, 60(6): 44-49.

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参考文献 0

	段文娟, 李　月, 崔　莉, 等. 低场核磁共振及成像技术分析白芍炮制过程中水分变化规律. 中国中药杂志, 2017, 42 (11): 2092- 2096.
	Duan W J, Li Y, Cui L, et al. Analyze moisture transformation and transport rules during processing of Paeoniae radix Alba by using low-field NMR. China Journal of Chinese Materia Medica, 2017, 42 (11): 2092- 2096.
	韩　彪, 张　萍, 郭素娟, 等. 失水对板栗种子超微结构与生理变化及萌发的影响. 基因组学与应用生物学, 2021, 40 (Z2): 2785- 2792.
	Han B, Zhang P, Guo S J, et al. Effects of water loss on ultrastructure and physiological changes and germination of Castanea mollissima seeds. Genomics and Applied Biology, 2021, 40 (Z2): 2785- 2792.
	胡绍彬. 2019. 基于高场核磁共振技术的‘琯溪蜜柚’粒化过程中水分研究. 福州: 福建农林大学.
	Hu S B. 2019. Water research in the process of granulation of Guanxi pomelo using high field nuclear magnetic resonance. Fuzhou: Fujian Agriculture and Forestry University. ［in Chinese］
	黄艳图, 何超明. 磁共振成像信噪比的评价方法. 磁共振成像, 2012, 3 (2): 149- 152.
	Huang Y T, He C M. Evaluation methodology of MRI SNR. Chinese Journal of Magnetic Resonance Imaging, 2012, 3 (2): 149- 152.
	李云龙. 叶秀树美的行道树良种—沼生栎. 园林, 2001, (1): 45.
	Li Y L. A thoroughbred border tree with beautiful leaves—Quercus palustris. Landscape Architecture Academic Journal, 2001, (1): 45.
	路　苗. 论核磁共振技术在食品检测方面的应用. 食品安全导刊, 2019, (3): 98.
	Lu M. The application of nuclear magnetic resonance technology in food detection. China Food Safety Magazine, 2019, (3): 98.
	盘喻颜, 段振华, 钟静妮. 2021. 利用低场核磁共振技术分析月柿果片微波间歇干燥过程中的内部水分变化. 食品工业科技, 42(14): 33−39.
	Pan Y Y, Duan Z H, Zhong J N. 2021. Analysis of internal moisture changes of persimmon slices during intermittent microwave drying using Low-Field NMR. Science and Technology of Food Industry, 42(14): 33−39.［in Chinese］
	彭麟麟. 2022. 栎属种子的低温耐受性和储藏寿命研究. 云南: 云南大学.
	Peng Q L. Study on chilling resistance and storage life of oaks’ seeds. Yunnan: Yunnan University. ［in Chinese］
	石　芳, 肖星凝, 杨雅轩, 等. 基于低场核磁共振技术研究不同热风干燥工艺条件下香菇复水过程中的水分传递特性. 食品与发酵工业, 2017, 43 (10): 144- 149.
	Shi F, Xiao X N, Yang Y X, et al. Characterization of moisture tansfer inrehydration process for dried mushroom (Lentinus edodes) by different drying methods. Food and Fermentation Industries, 2017, 43 (10): 144- 149.
	宋　平, 徐　静, 马贺男, 等. 利用低场核磁共振及其成像技术分析水稻浸种过程水分传递. 农业工程学报, 2016, 32 (6): 204- 210. doi: 10.11975/j.issn.1002-6819.2016.06.028
	Song P, Xu J, Ma H N, et al. Moisture phase state and distribution characteristics of seed during rice seed soaking process by low field nuclear magnetic resonance. Transcations of the Chinese Society of Agricultural Engineering, 2016, 32 (6): 204- 210. doi: 10.11975/j.issn.1002-6819.2016.06.028
	孙炳新, 赵宏侠, 冯叙桥, 等. 2016. 基于低场核磁和成像技术的鲜枣贮藏过程水分状态的变化研究. 中国食品学报, 16(5): 252-257.
	Sun B X, Zhao H X, Feng X Q , et al. 2016. Studies on the change of moisture state of fresh Jujube during storage base on LF-NMR and MRI. Journal of Chinese Institute of Food Science and Technology, 16(5): 252-257. ［in Chinese］
	孙　旭, 姜　东, 徐　莉, 等. 银杏白果干燥过程中水分分布及迁移的变化. 南京林业大学学报(自然科学版), 2019, 43 (6): 188- 192.
	Sun X, Jiang D, Xu L, et al. Moisture distribution and migration of Ginkgo biloba seeds during air drying process. Journal of Nanjing Forestry University (Natural Sciences Edition), 2019, 43 (6): 188- 192.
	万　娟, 陈　中, 杨晓泉. 核磁共振技术及其在食品加工中的应用. 食品与药品, 2006, (11): 17- 19. doi: 10.3969/j.issn.1672-979X.2006.11.005
	Wan J, Chen Z, Yang X Q. Nuclear magnetic resonance technique and its application in food processing. Food and Drug, 2006, (11): 17- 19. doi: 10.3969/j.issn.1672-979X.2006.11.005
	王　逗. 核磁共振原理及其应用. 现代物理知识, 2005, 17 (5): 50- 51.
	Wang D. Principle and application of nuclear magnetic resonance. Modern Physics, 2005, 17 (5): 50- 51.
	徐建国, 徐　刚, 张绪坤, 等. 利用核磁共振成像技术分析胡萝卜干燥过程中内部水分传递. 农业工程学报, 2013, 29 (12): 271- 276. doi: 10.3969/j.issn.1002-6819.2013.12.034
	Xu J G, Xu G, Zhang X K, et al. Moisture transport in carrot during hot air drying using magnetic resonance imaging. Transcations of the Chinese Society of Agricultural Engineering, 2013, 29 (12): 271- 276. doi: 10.3969/j.issn.1002-6819.2013.12.034
	袁　鸣, 朱铭玮, 解志军, 等. 核磁共振技术在沼生栎种子失水过程中水分相态变化. 林业科学, 2023, 59 (11): 42- 48.
	Yuan M, Zhu M W, Xie Z J, et al. Changes of water phases during desiccation of Quercus palustris seeds by Nuclear Magnetic Resonance. Scientia Silvae Sinicae, 2023, 59 (11): 42- 48.
	Cheng S, Li R, Yang H, et al. Water status and distribution in shiitake mushroom and the effects of drying on water dynamics assessed by LF-NMR and MRI. Drying Technology, 2020, 38 (8): 1001- 1010. doi: 10.1080/07373937.2019.1625364
	International Seed Testing Association (ISTA). 2004. International rules for seed testing. Chapter 6: biochemical test for viability. Bassersdorf: International Seed Testing Association (ISTA).
	Jin X, Van A H, Boom R M. Anomalies in moisture transport during broccoli drying monitored by MRI?. Faraday Discussions, 2012, 158, 65- 75. doi: 10.1039/c2fd20049j
	Rathjen J R, Srtounina E V, Mares D J. Water movement into dormant and non-dormant wheat (Triticum aestivum L. ) grains. Journal of Experimental Botany, 2009, 60 (6): 1619- 1631. doi: 10.1093/jxb/erp037
	Scheenen T W J, Van D D, De J P A, et al. Quantification of water transport in plants with NMR imaging. Journal of Experimental Botany, 2000, 51 (351): 1751- 1759. doi: 10.1093/jexbot/51.351.1751
	Volkov A G, Hairston J S, Patel D, et al. Cold plasma porationand corrugation of pumpkin seed coats. Bioelectrochemistry, 2019, 128, 175- 185. doi: 10.1016/j.bioelechem.2019.04.012
	Zhu M W, Dai S, Ma Q Y, et al. Identifcation of the initial water-site and movement in Gleditsia sinensis seeds and its relation to seed coat structure. Plant Methods, 2021, 17, 55. doi: 10.1186/s13007-021-00756-z

含水量Water content（%）	SNR1	下降幅度Descend range （%）	SNR2	下降幅度Descend range （%）	SNR3	下降幅度Descend range （%）	SNR4	下降幅度Descend range （%）	SNR5	下降幅度Descend range （%）	SNR6	下降幅度Descend range （%）	SNR7	下降幅度Descend range （%）	SNR8	下降幅度Descend range （%）	SNR9	下降幅度Descend range （%）
38.0	23.50	—	11.17	—	15.50	—	7.17	—	4.50	—	2.17	—	5.17	—	6.17	—	3.00	—
30.0	14.67	37.57	8.33	25.43	14.67	5.35	6.12	14.64	3.30	26.67	1.70	21.66	3.67	29.01	4.33	29.82	2.12	29.33
25.0	6.67	71.62	5.60	49.87	12.17	21.48	4.93	31.24	1.80	60.00	1.59	26.73	3.17	38.68	3.50	43.27	1.33	55.67
20.0	2.00	91.49	4.00	64.19	9.00	41.94	4.51	37.10	1.52	66.22	1.50	30.88	2.67	48.36	2.67	56.73	1.27	57.67
15.0	1.50	93.62	3.00	73.14	8.00	48.39	3.50	51.19	1.33	70.44	1.33	38.71	2.50	51.64	2.33	62.24	1.19	60.33
10.0	1.00	95.74	1.86	83.35	5.00	67.74	1.86	74.06	1.14	74.67	1.14	47.47	1.23	76.21	1.57	74.55	1.14	62.00

[1]	袁鸣,朱铭玮,解志军,康真,张中会,李淑娴. 核磁共振技术在沼生栎种子失水过程中水分相态变化[J]. 林业科学, 2023, 59(11): 42-48.
[2]	李继东毕会涛武应霞冯建灿. 移栽期间胁迫对苗木影响的研究进展[J]. 林业科学, 2008, 44(6): 137-142.
[3]	高永胡春元董智张秀卿. 土壤冻结过程中水分迁移动向的研究[J]. 林业科学, 2000, 36(4): 126-128.
[4]	尚德库. 非等温条件下木片碎料中的水分迁移特性[J]. , 1992, 28(1): 52-57.