外源硒对芒果硒含量及果实营养品质的影响

探讨叶面喷施和土施外源硒对芒果叶片和果实硒含量、果实矿质元素含量及营养品质的影响，以期为富硒芒果的安全生产提供理论依据和技术支持。以“桂热 82号”芒果为试材，叶面喷施以亚硒酸钠为硒源，设置0.0、25.0、50.0、100.0、150.0和 200.0 mg/L 6个浓度水平，于生理落果结束后，每 15 d喷施一次，连喷 2次。土施设置亚硒酸钠处理和硒酸钠处理，施肥量为 10 g/株，于花期沟施。结果表明，芒果叶片和果实中的硒含量随着叶面喷硒浓度的增加而递增。叶面喷施 50 mg/L亚硒酸钠可显著提高果实 Vc含量，200 mg/L亚硒酸钠可显著提高果实K、可滴定酸含量，100～ 200 mg/L亚硒酸钠可显著降低果实Zn、Ca含量。土施相同量的亚硒酸钠和硒酸钠均可显著提高芒果叶片和果实硒含量。土施硒酸钠叶片和果实硒含量显著高于亚硒酸钠。土施 10 g/株亚硒酸钠显著降低果实 Ca、Mg含量，土施 10 g/株硒酸钠显著提高果实 K、Vc含量，降低果实 Ca含量。叶面喷硒和土壤施硒均可显著提高芒果叶片和果实硒含量，其中叶面喷硒提高幅度远大于土壤施硒提高幅度。土施硒酸钠比亚硒酸钠更容易被芒果吸收。富硒芒果生产上推荐叶面喷施 25.0～ 50.0 mg/L亚硒酸钠，或者土施 10 g/株硒酸钠。     

叶面施硒对黑豆硒吸收转运特征及籽粒硒形态的影响

为了明确叶面喷施亚硒酸钠对黑豆硒吸收转运特征及籽粒硒形态的影响,采用小区试验在黑豆结荚兴盛期进行一次性叶面喷施亚硒酸钠(施硒量分别为0、6、12、18和24 mg·m^-2)处理,分析比较不同浓度亚硒酸钠处理下黑豆产量、各器官硒含量、籽粒有机硒转化率和品质性状的差异。结果表明,各施硒水平对黑豆各器官总硒含量均有提升作用,在24 mg·m^-2硒处理时各器官总硒含量最大,根、茎、荚和籽粒硒含量分别较对照提高了8.74、8.37、9.85和65.21倍,硒处理后各器官总硒含量呈现籽粒>根≈荚>茎的特点。籽粒中硒以有机硒形态存在,且有机硒转化率随着亚硒酸钠浓度的增加呈下降趋势,在0、6、12、18和24 mg·m^-2施硒处理时,有机硒含量分别为0.071 4、1.101 8、1.510 6、1.811 1和2.093 5 mg·kg^-1,有机硒转化率分别为94.52%、84.81%、70.30%、60.11%和52.43%。叶面喷施亚硒酸钠显著提高了黑豆籽粒蛋白质含量和分离蛋白硒含量,但对脂肪含量的影响较小,在24 mg·m^-2硒处理时蛋白质含量和分离蛋白硒含量分别较对照增加了2.4个百分点和117.35倍,分离蛋白硒含量占有机硒和总硒含量的比例分别为90.29%和47.39%。适宜浓度亚硒酸钠叶面喷施对黑豆产量具有促进作用,但浓度过高导致增产效果减弱。综上,叶面喷施亚硒酸钠可提高黑豆各器官总硒含量,但黑豆籽粒有机硒转化率随喷施浓度的增加呈下降趋势,且黑豆籽粒有机硒主要以蛋白质形式存在。本研究结果为应用外源硒强化技术生产富硒黑豆提供了科学依据。     

叶面喷施亚硒酸钠对葡萄果实品质及叶片衰老的影响

以3年生露地栽培葡萄户太8号为试材,采用不同浓度、不同时期叶面喷施亚硒酸钠的方法,探究提高葡萄果实硒含量方法及其延缓叶片衰老的效应。结果表明,喷硒后新抽生出副梢新叶中的硒含量与老叶中硒含量呈高度正相关(r=0. 99),硒在葡萄植株内具有移动性,可重复利用。不同浓度处理以50 mg/L亚硒酸钠处理后的果实品质最好;不同时期处理下始着色期处理后的果实品质最好。50 mg/L亚硒酸钠处理后延缓叶片衰老效果最明显。叶面喷施亚硒酸钠可有效提高葡萄果实含硒量从而提高果实品质,有效提高叶片叶绿素含量从而增加叶片光合量进一步延缓叶片衰老。     

喷硒时期与浓度对红富士苹果果实品质及各部位全硒和有机态硒含量的影响

本试验通过叶面喷施外源硒肥、原子荧光法测定样品硒含量,研究不同硒喷施浓度对果树各部位无机硒含量、硒有机化程度及果实品质的影响,筛选红富士苹果的最佳施硒方案。结果表明, 1）在花期和幼果期叶面施硒效果较为稳定,叶片和果实中硒的有机化程度高。在接近果实着色期或采收期叶面施硒,虽然果实中总硒量较高,但硒的有机化程度较低。2）相同喷施浓度下,树体各器官硒含量顺序依次为叶＞枝＞果＞根,果树地上部分配的硒占较大比例。3）叶面喷施硒可增加果实中可溶性固形物、可溶性糖和Vc 含量,从而改善了果实风味,但降低了果实硬度,影响其贮藏运输品质。4）红富士苹果以在5、6、7月中旬喷施 3 次100 mg/L 亚硒酸钠效果最佳,此时叶片中总硒含量为2728.30 g/kg, FW,有机化程度达85.71%。各项果实品质指标佳,平均单果重达256.8 g。果实总硒含量为10.10 g/kg, FW,有机化程度为87.72%。     

喷施不同浓度亚硒酸钠对葡萄生理特性和品质的影响

以3年生露地栽培‘夏黑’葡萄为供试作物,分别在开花期、坐果期、果实膨大期及果实转色期喷施浓度为0 mg·L^-1(CK)、20 mg·L^-1(T1)、40 mg·L^-1(T2)、60 mg·L^-1(T3)和80 mg·L^-1(T4)的亚硒酸钠溶液,探究其对葡萄生理特性及果实品质的影响。结果表明,1)喷施亚硒酸钠对葡萄生理特性的影响。叶片可溶性蛋白含量,脯氨酸含量,SOD、POD、CAT活性随亚硒酸钠浓度增加呈先升高后降低的趋势,亚硒酸钠浓度在40mg·L^-1时达到最大值,分别较CK显著提高了11.27%、11.89%、10.67%、8.33%、15.60%,各处理叶片相对电导率、MDA含量均低于CK,且亚硒酸钠浓度在40 mg·L^-1处理较CK显著降低了7.73%、14.39%;2)对果实品质的影响。40 mg·L^-1亚硒酸钠处理果实单粒重、单穗重、果形指数、可溶性蛋白、总酚含量分别较CK显著提高了8.81%、6.82%、7.06%、6.93%、24.43%,固酸比在40和80 mg·L^-1亚硒酸钠时分别较CK显著增大8.05%、7.95%,Vc含量在亚硒酸钠浓度为40、60mg·L^-1时较CK显著提高7.52%、7.60%,类黄酮和果实花青素含量在亚硒酸钠浓度为60 mg·L^-1时分别较CK显著提高20.14%、18.80%;果实硒含量与亚硒酸钠处理浓度呈正相关关系,分别是CK的1.75、3.64、6.69、8.92倍。主成分分析结果表明,5种施硒水平对提高葡萄生理特性和改善果实品质顺序依次为T2>T3>T1>T4>CK,综合分析,应用40 mg·L^-1亚硒酸钠处理效果最佳。     

叶面喷施不同形态硒对草莓吸收和转运硒的影响

采用温室大棚试验,研究了叶面喷施硒酸钠和亚硒酸钠对提高草莓硒含量的影响以及硒在草莓植株中的转运和分布,旨在为富硒水果的开发和生产提供理论依据。本试验在草莓初花期进行叶面喷施亚硒酸钠和硒酸钠,当喷硒量为20、40、60 g Se·hm~(-2)时,亚硒酸钠处理40 d后草莓果实样品中硒含量分别为0.03、0.10、0.15 mg·kg~(-1)FW,分别为对照的3、20倍和30倍;硒酸钠处理40d后草莓果实硒含量分别为0.05、0.12、0.17 mg·kg~(-1) FW,是对照处理的5、24倍和34倍。但是叶面喷施的硒持续供给果实的能力有限,随着草莓果实的连续生长,后期采收的草莓中硒含量显著下降。叶面喷硒后,叶片吸收的亚硒酸钠约有30%转移到了根部,而硒酸钠则更多地累积于叶片中,转移到根部的量不到15%。草莓初花期叶面喷施硒可以显著提高前期草莓果实中硒的含量,随着采收期的延长,草莓中硒的含量显著下降,喷施亚硒酸钠的处理硒向根部转移的能力高于硒酸钠的处理。     

叶面硒肥对春小麦的富硒效应及硒素吸收分配的影响

采用田间试验法,研究了不同浓度及不同时期喷施叶面硒肥对春小麦硒素吸收、转化分配规律及硒肥利用率的影响。结果表明:(1)在拔节期和孕穗期2次喷施10~20 mg/kg或孕穗期1次喷施40~50 mg/kg的亚硒酸钠溶液,都能使春小麦达到富硒标准。(2)在拔节、孕穗、乳熟期喷施40 mg/kg亚硒酸钠溶液都能使籽粒中的硒素含量达到富硒标准,孕穗至乳熟期为最佳喷施时期。(3)在生育进程中,全株硒素含量在0.062~0.187 mg/kg之间变化,平均0.086 mg/kg。叶面硒肥能显著提高各器官硒素含量,且富集效应顺序是叶籽粒颖壳茎。(4)全株硒素吸收量和吸收速率动态变化可分别用一元三次方程式和一元二次方程式定量表达。孕穗期喷施40 mg/kg亚硒酸钠溶液时,全株硒素最快吸收速率为0.030 5μg/(d·株),与对照相比,提高了9.5倍,出现时间提前4 d。     

叶面喷施纳米硒肥对金丝小枣产量和品质的影响

硒是人体所必需的微量元素,随着人们对硒产品认识程度逐渐加深,富硒食品在市场上出现的越来越多。以乐陵金丝小枣为对象,于枣果幼果期、果实膨大期、转色期叶面喷施纳米硒肥,探究不同浓度梯度(0、4.8、9.6、14.4 mL/L)纳米硒肥对枣产量和品质的影响。结果表明,叶面喷施纳米硒肥可显著增加金丝小枣的产量和品质,随着喷施硒浓度的增加,金丝小枣枣果中硒含量逐渐增加,但产量出现先增加后降低的趋势,叶面喷施硒肥可显著增加可溶性固形物含量、维C含量以及枣果中和叶片中矿质元素含量,以9.6 mL/L浓度处理下效果最佳,产量增加33.0%,可溶性固形物显著增加8.4%,维C含量显著增加53.5%,且枣果中硒含量达0.28 mg/kg,较空白对照显著增加171.8%,矿质元素磷、钾、钙、镁、硼、铁的含量增加最为显著。综合分析,叶面喷施纳米硒肥浓度为9.6 mL/L时增产提质效果最佳。     

不同时期叶面喷硒对冬枣含硒量与品质的影响

为了筛选冬枣(Zizyphus jujuba Mill. var. Dongzao)的最佳施硒方案,通过在展叶期、幼果期、果实膨大期、白熟期分别进行一次性叶面喷施亚硒酸钠溶液(含硒量为45 mg·L~(-1),施硒量为27 mg·株~(-1)),研究不同时期施硒对冬枣叶片和果实的硒含量、硒有机化程度以及果实品质的影响。结果表明:在果实膨大期或白熟期叶面喷施硒溶液后,叶片和果实的总硒含量均得到显著提高,其中果实膨大期喷硒使总硒和有机硒含量增幅最大,冬枣果实含硒量由25μg·kg~(-1)提高到76μg·kg~(-1)。不同时期叶面喷硒对冬枣果实品质的作用效果不尽相同,果实膨大期施硒对冬枣品质的改善效果最佳,此时冬枣果实中的可溶性固形物、可溶性糖、维生素C、总黄酮含量和糖酸比均达到最高值,分别较对照显著提高了13.30%、17.17%、16.33%、29.17%和28.89%。综合研究结果表明,生产富硒冬枣以在果实膨大期一次叶面喷硒的效果最佳。     

萌芽前叶面喷施硒酸钠提高茶叶含硒量及品质

  【目的】  探究在茶树不同生育时期叶面喷施不同硒肥对夏茶产量、品质及硒含量的影响,为生产富硒茶提供技术依据。  【方法】  田间试验在浙江嵊州进行,供试茶树品种为‘中茶108’。 试验采用二因素列区设计,主处理为硒肥种类(A因素),副处理为硒肥喷施时期(B因素)。主处理设喷施清水对照(A0)、硒酸钠(A1)、亚硒酸钠(A2)和酵母硒(A3);副处理设夏茶顶芽萌发前(5月12日,B1)与1芽1叶期(5月20日,B2)两个喷施时期。硒肥喷施浓度均为Se 50 mg/L,硒肥溶液喷施量为1.8 L/m2。当茶树蓬面1芽2叶占比达30%左右时,每个小区随机选取30 cm×30 cm茶蓬,调查蓬面新梢总数、1芽2叶数量、1芽2叶长度和百芽重。同时,取1芽2叶新梢样品,测定茶多酚、儿茶素、咖啡碱、游离氨基酸、花青素以及硒含量。  【结果】  与A0B1处理相比,A3B1处理茶树萌展值显著降低了0.14,但对茶树蓬面新梢总数无明显影响;A2B1处理茶树1芽2叶新梢长度和百芽重分别显著降低了1.04 cm和1.94 g。A1B2和A3B2处理茶树蓬面新梢总数分别显著降低了17.66和22.33,但不影响其萌展值;A1B2显著降低茶树1芽2叶新梢长度和百芽重,分别降低0.88 cm和1.70 g。A1B1和A2B1处理的茶叶总硒含量分别显著提高了1.15和1.47 mg/kg,有机硒含量分别显著提高了1.13 和1.38 mg/kg,但A3B1处理未显著提高茶叶硒含量。A1B2、A2B2和A3B2处理均显著提高了茶叶总硒和有机硒含量,其中总硒增加量分别为5.97、7.88 和2.61 mg/kg,有机硒含量分别增加了5.17、7.51和2.48 mg/kg。另外,A1B1显著降低了茶叶咖啡碱、没食子酸和儿茶素含量;A1B2处理显著降低了茶叶游离氨基酸含量,但显著增加了茶多酚和儿茶素总量,儿茶素组成中的没食子酸、表没食子儿茶素没食子酸酯和表儿茶素没食子酸酯等酯型儿茶素显著增加。  【结论】  夏茶萌芽前喷施外源硒能够提高茶叶总硒和有机硒含量,改善茶叶品质,尤以硒酸钠的效果最好。     

天然富硒土壤上三种蔬菜对硒的吸收与转化差异

【目的】研究对硒 (Se) 不同敏感性蔬菜对天然富硒土 (Se ≥ 0.4 mg/kg) 中硒的吸收和转化差异,为富硒土壤生产富硒蔬菜提供理论与技术指导。【方法】以大蒜、芥菜和菠菜三种蔬菜为试验材料,在全硒含量为0.29、0.58、0.98、2.07 mg/kg的四种土壤上进行了盆栽试验 (依次标记为Se_0.29、Se_0.58、Se_0.98、Se_2.07),并测定四种土壤中不同形态硒的含量。芥菜和菠菜于生长40 d、53 d、68 d和82 d后取样,测定蔬菜可食部分硒含量;于生长97 d后收获,分为根部和地上部。大蒜于生长42 d、68 d、82 d、120 d后取样,测定地上部硒含量;于生长165 d后收获,分为根部、鳞茎和叶。测定供试蔬菜总硒含量、有机硒含量,计算不同硒含量土壤上蔬菜对硒的吸收和转化系数。【结果】三种蔬菜中芥菜的生长对土壤硒最为敏感,芥菜可食部位生物量鲜重以Se_0.29处理最高,菠菜和大蒜均以Se_0.58处理最高,与Se_2.07处理均达显著差异。三种蔬菜地上部硒含量在整个生育期总体呈现增加的趋势,不同生育期均表现为大蒜 > 芥菜 > 菠菜。收获期三种蔬菜各部位的硒含量随着土壤硒含量 (0.29～2.07 mg/kg) 的增加而增加,表现为Se_2.07 > Se_0.98 > Se_0.58 > Se_0.29,Se_2.07处理的菠菜地上部和地下部硒含量分别是其Se_0.29处理的8.63倍和7.10倍,芥菜是12.25倍和23.29倍,Se_2.07处理大蒜鳞茎和叶部硒含量是Se_0.29处理的39.92倍和4.90倍;可食部位硒含量为大蒜 (7.25～289 μg/kg) > 芥菜 (1.22～14.9 μg/kg) > 菠菜 (0.73～6.30 μg/kg),均表现为地下部 > 地上部,Se_2.07处理菠菜根部硒含量是茎叶的4.80倍,芥菜是12.06倍,大蒜是8.22倍。在富硒土壤Se_0.98和Se_2.07处理条件下,大蒜和芥菜能从土壤中富集硒,吸收系数是菠菜的3.06～8.47倍和1.58～5.8倍,均达到了富硒蔬菜标准 (≥ 0.01 mg/kg)。三种蔬菜可食部位有机硒含量占总硒比例为73.5%～84.7%,并随土壤硒含量的增加而增加,其中Se_2.07与Se_0.29处理差异显著;蔬菜硒含量不但与土壤总硒含量相关,而且与有效态硒含量呈显著正相关。【结论】蔬菜种类和土壤硒含量均影响蔬菜硒的吸收、转化和富集。三种蔬菜对土壤硒的敏感性以芥菜最强。蔬菜硒含量和可食用部位有机硒的转化率均随着土壤硒含量的增加而增加,与土壤总硒含量和有效态硒含量呈显著正相关。富硒能力为大蒜 > 芥菜 > 菠菜,在天然富硒土壤上生长的大蒜和芥菜硒含量易达到富硒蔬菜标准,而菠菜未显示出富硒能力。因此,虽然土壤硒含量高影响了大蒜和芥菜的生长,但大蒜和芥菜具有较强的将硒转移到可食部位的能力,可作为富硒蔬菜生产。     

Effect of selenium treatment on mineral nutrition, bulb size, and antioxidant properties of garlic (Allium sativum L.)

Foliar selenium (Se) treatment of garlic at concentrations of 10, 50, and 100 μg of Se/mL was carried out in open field conditions in 2008 and 2009 in Estonia. Bulb weight and yield structure, content of total Se, S, N, P, K, Ca, and Mg, ascorbic acid content (AAC), pungency, total phenolics, and total antioxidant capacity (TAC) were determined. The highest level of Se decreased total S, K, and Ca in both years; no negative impact on bulb weight was observed. In 2009 Se10 treatment had significantly more bulbs with the largest diameter compared to the other treatments. In 2008, the AAC was decreased by Se50 and the content of total phenolics by all Se treatments; however, TAC was increased. Foliar Se fertilization of garlic at rates of 10-50 μg of Se/mL can be recommended to increase the number of large bulbs and increase bulb antioxidant capacity.     

Effect of selenium on the yield and quality of green tea leaves harvested in early spring

Foliar applications of a fertilizer of selenite or selenate were carried out to determine the influence of selenium on the yield and quality of green tea leaves harvested in early spring. Numbers of sprouts and the yield were significantly increased by the application of selenium. The sweetness and aroma of green tea leaves were also significantly enhanced, and bitterness was significantly decreased by the application of selenium. However, no significant differences were found in sweetness, bitterness, and aroma between tea leaves fertilized with selenite and selenate. Se concentration was significantly increased by selenium fertilization, and tea enriched by sodium selenate had a significantly higher selenium content than did tea enriched by sodium selenite. Total amino acid and vitamin C contents were significantly enhanced by the application of selenium. Tea polyphenol contents were significantly decreased by fertilization with selenium. The marked difference of tea polyphenols was also found between applications of selenite and selenate.     

Foliar application and uptake of selenium extracted from ryegrass

In a pot experiment a water extract from ryegrass (Lolium perenne) containing 21 mg/L selenium (Se) was sprayed on ryegrass, and the uptake of Se was compared with the uptake of Se applied as sodium selenite. The amount of Se recovered from the plants (0 to 53 mg/kg) was a linear function of the amount of Se applied (0 to 130 g/ha), both for the Se in the extract and for the sodium selenite. A total of 2.8 times more Se was recovered from the plants sprayed with the extract than from the plants sprayed with sodium selenite. When the plants were washed with Triton X‐100 the difference was still higher: from the ryegrass sprayed with the extract 5.3 times more Se was recovered from the grass sprayed with the extract than from the grass sprayed with sodium selenite.     

硒粮预防克山病的试验研究

研究结果表明;给农作物喷施亚硒酸钠水溶液,通过叶面吸收可增加籽实含硒量,食硒粮给人体补硒可有效地预防克山病发病。文中介绍了农作物喷硒的方法,筛选出喷施是提高籽实含硒量的有效途径,对不同作物的喷施生育期及亚硒酸钠用量等作了探讨。喷施的籽实含硒量比当地未喷的提高3—6倍,达到非病区含硒水平。食用硒粮人的发硒含量由0.085ppm提高到0.299ppm,与非病区发硒0.304ppm十分吻合,还说明硒粮中的硒(有机态硒)利于机体的吸收利用,因而能有效地提高人体环境含硒水平,且含量适当、对人安全。     

Influence of Nitrogen and Sulfur Fertilization on the Alliin Content of Onions and Garlic

Abstract

Onion (Allium cepa L.) and garlic (Allium sativum L.) were among the earliest cultivated crops and have been popular in folk medicine for centuries. Alliins (cysteine sulfoxides) are the characteristic sulfur (S) containing secondary metabolites of Allium species like onions, shallot, garlic, leek and chives and they cause taste and sharpness and are criteria for the pharmaceutical quality. The influence of the S nutritional status on the content of secondary S containing metabolites was shown for different crops such as oilseed rape, mustard, nasturtium, and allium species. It was the aim of this study to investigate the influence of the S and nitrogen (N) supply on the alliin content of onion and garlic and to evaluate the significance for crop quality. In a greenhouse experiment three levels of N and S were applied in factorial combinations of 0, 50, and 250 mg pot^?1 S and 250, 500, and 1000 mg pot^?1 N. 8 plants were grown in a Mitscherlich pot containing 8 kg sand. Leaves and bulbs were sampled twice during the growth period in order to follow up translocation processes. The first sampling was carried out when leaves were developed, but bulb growth had not yet started and the second one during main bulb growth. An increasing S supply was related to an increasing alliin content in leaves and bulbs of both crops, whereas nitrogen fertilization had only a minor influence. The alliin content in bulbs could be doubled by S fertilization. A translocation of alliin from leaves to bulbs was found so that time of harvest has a strong influence on the alliin content. At the beginning of plant development high alliin contents were found in leaves, while with bulb development they were translocated into this plant organ. The results show that the potential health benefits of Allium species could be distinctly improved by S fertilization.