不同类型花生浸种过程物理特性变化及内部水分迁移规律

Physical Characteristics Changes and Internal Water Migration of Different Types of Peanut during Seed Soaking Process

探究高油酸、高蛋白和普通花生在不同温度(25℃和31℃)和浸泡时间(0、3、6、9、12 h)下的浸种特性,利用低场核磁共振成像技术动态监测种子水分相态和迁移,明确不同类型花生种子浸种过程的物理特性变化和吸水动态,旨在探寻不同类型花生适宜的浸种时间和温度,降低花生萌发时种皮破损率。结果表明,不同温度和浸泡时间处理下,3种类型花生种子的质量增加率、体积增加率、含水率增加率及总信号幅值等与花生浸泡时间和温度呈显著正相关(P<0.05)。高蛋白花生YH9326的蛋白质与高蛋白标准比值(P/P标)最高(1.37),在25℃浸种12 h后质量增加率最高(58.91%),与31℃处理无显著差异;25℃下浸种3、6 h含水率增加率较31℃分别下降22%、6%;2种温度下非结合水信号幅值增加率在浸种12 h显著高于浸种9 h,显示出种子持续吸水状态;与31℃浸种相比,25℃下浸种3 h总水和结合水信号幅值增加率分别提高42%和10.0倍。普通花生HY38的油酸与亚油酸比值(OA/LA)最低(1.30),31℃浸种3、6、9 h后,其体积增加率显著提高,分别较25℃浸种时提高8%、17%、25%;浸种9 h后含水率增加率比25℃提高20%;浸种3、6 h,其结合水信号幅值增加率较25℃分别下降35%和29%,但非结合水信号幅值增加率显著提高99%和55%;在31℃浸种6、9 h,非结合水信号幅值增加率无显著差异。高油酸花生YH37的油酸与亚油酸比值(OA/LA)最高(11.1),在25℃下浸种3 h体积增加率(46.13%)高于YH9326和HY38,相较于31℃浸种3、6 h后,其非结合水信号幅值增加率分别降低13%、9%,结合水信号幅值增加率显著提高3.5倍和1.3倍。在25℃浸种,高油酸花生YH37和高蛋白花生YH9326的非结合水信号幅值增加率虽表现持续吸水到浸种12 h,但在浸种6、9 h无显著差异。高蛋白花生YH9326及高油酸花生YH37适宜在25℃浸种6 h,可完成初始快速吸胀吸水;普通花生种子HY38适宜31℃浸种6 h,基本完成初始快速吸胀吸水。

To reduce the damage rate of seed coat during peanut germination,the suitable soaking time and temperature of different types of peanuts should be explored.The seed soaking characteristics of high oleic acid(YH37),high protein(YH9326)and common(HY38)peanuts at different temperatures(25℃and 31℃)and soaking time(0,3,6,9,12 h)were investigated.The water phase state and migration of seeds were dynamically monitored by the low field nuclear magnetic resonance imaging technology,and the physical characteristics and water absorption dynamics of different types of peanut seeds during seed soaking were clarified.The results showed that the mass and volume increase rate,moisture content increase rate and total signal amplitude of the three types of peanut seeds were significantly positively correlated with peanut soaking time and temperature(P<0.05).The ratio of protein to high protein standard(P/P standard)(1.37)of YH9326 was the highest,and its mass gain rate(58.91%)was the highest after soaking at 25℃for 12 h,which was not significantly different from that at 31℃.The increase rates of moisture content of seeds soaked at 25℃for 3 h and 6 h were 22%and 6%lower than that at 31℃.At the two temperatures,the increase rate of unbound water signal amplitude at 12 h was significantly higher than that at 9 h,indicating that the seeds were absorbing water constantly.Compared with 31℃,the increase rate of signal amplitude of total water and bound water at 25℃for 3 h increased by 42%and 10.0 times,respectively.The ratio of oleic acid to linoleic acid(OA/LA)(1.30)of HY38 was the lowest.At 31℃,the volume increase rate after 3 h,6 h and 9 h of soaking increased significantly by 8%,17%and 25%compared with that at 25℃,respectively.The increase rate of moisture content after soaking for 9 h was 20%higher than that at 25℃.The increase rate of bound water signal amplitude decreased by 35%and 29%after 3 h and 6 h of soaking,respectively,compared with 25℃,but the increase rate of non-bound water signal amplitude increased by 99%and 55%,which were not significantly different after soaking at 31°C for 6 h and 9 h.The high oleic acid peanut YH37 displayed the highest oleic acid to linoleic acid ratio(OA/LA)(11.1),with the highest volume increase rate(46.13%)in three peanut cultivars after 3 h of soaking at 25℃.The increase rate of non-bound water signal amplitude decreased by 13%and 9%,respectively,compared with that at 31℃for 3 h and 6 h.In contrast,the increase rate of bound water signal amplitude significantly increased by 3.5 times and 1.3 times.Soak seeds At 25℃,the non-bound water signal amplitude increase rate of YH37 and YH9326 showed continuous water absorption up to 12 h of soaking,with no significant difference at 6 h and 9 h.In summary,high protein peanut YH9326 and high oleic acid peanut YH37 are suitable for seed soaking at 25℃for 6 h to complete initial rapid swelling and water absorption,while common peanut HY38 should be soaked at 31℃for 6 h for the same.