赣南地区设施菜地土壤全硒含量分布特征

为探究江西省赣州设施菜地土壤全硒（Se）的含量及其分布特征,于2021年对赣南地区设施蔬菜大棚采集0～20 cm耕层土壤样235件,测定了土壤采样点的经纬度、海拔及土壤中全硒含量和理化性质。结果表明,赣南地区设施菜地土壤全硒质量分数平均为0.31 mg/kg,变化范围为0.03～1.25 mg/kg,全硒含量分布频率符合正态分布。研究区域设施菜地富硒土壤资源较为丰富,85.1%的样点数土壤全硒含量处于足硒及以上水平（>0.175 mg/kg）,其中有22.1%的样点数土壤属于富硒水平标准（>0.400～3.000 mg/kg）,而富硒土壤主要集中在赣南地区的正西部及东北部等部分区域;7.2%和7.7%的样点数土壤全硒质量分数分别达硒不足（>0.125～0.175 mg/kg）和潜在硒不足水平（≤0.125 mg/kg）,二者主要集中在赣南地区西南角部分区域,不存在硒中毒区域。海拔每增加1 m,设施土壤全硒质量分数降低5.35×10-4 mg/kg;纬度每增加1°和pH值每增加一个单位,土壤全硒质量分数分别增加0.090和0.049 mg/kg。综上,赣南地区设施菜地土壤硒资源具有较大利用潜力,并可依据研究区域全硒含量分布特征开展具有针对性的设施富硒蔬菜发展策略。     

甘肃省民勤县骏枣园土壤硒特征及有效性

[目的]分析甘肃省民勤县骏枣园土壤硒分布状况及有效性,为富硒骏枣产业发展提供理论依据。[方法]采用连续浸提的方法对民勤县3个骏枣园0—60 cm土壤全硒及各形态硒含量进行测定、并对其分布特征及有效性进行了分析。[结果](1)土壤全硒含量变幅为24～520μg/kg,平均值为210.625μg/kg,全硒表现为不缺乏。(2)在0—60 cm土层内,随着土层深度增加,3个果园土壤全硒含量逐步减少,且均呈现：六沟>张坝>新果园关系。表层土壤(0—20 cm)属于足硒类型,亚表层土壤(20—40 cm)以足硒和少硒为主,底层土壤(40—60 cm)表现为足硒、少硒和缺硒。(3)土壤有效硒含量42.5μg/kg,占全硒的20.2%。其中,水溶态硒含量为1.1～1.4μg/kg,交换态硒含量1.4～2.8μg/kg,两者仅占有效硒的7.7%,其余为有机态硒。3个枣园土壤有机态硒含量为：新果园>六沟>张坝。(4)土壤有效硒随着开垦年限延长而增加,即新果园>六沟>张坝。(5)全硒、有效硒和无效硒均呈现：树下>行间。[结论]民勤县骏枣园土壤全硒不缺乏,但有效硒缺...     

河北省主要苹果产区土壤养分状况与演变

通过对河北省主要果园产区的土壤养分测定、定位监测等方法,研究了河北省土壤养分现状与动态变化及其养分在0～60 cm土壤剖面的分布特点,旨在为苹果的科学施肥提供理论依据。主要结果:河北省主要苹果园0～20 cm土壤全氮、有机质、有效磷、速效钾、有效铁、有效锌平均含量分别为1.16 g/kg、17.99 g/kg、118.26 mg/kg、329.70 mg/kg,15.33 mg/kg、3.69 mg/kg,同比于第二次土壤普查时期,各养分含量分别增加了0.43g/kg、6.49 g/kg、111.96 mg/kg、201.50 mg/kg、7.13 mg/kg、3.16 mg/kg。有机质及养分含量分布:基于第二次土壤普查分级标准,土壤有机质在10.00～20.00 g/kg的果园占60.3%,处于较低水平;全氮在1.00～1.50 g/kg果园占44.5%,处于中等水平;有效磷40.00 mg/kg、速效钾200.00 mg/kg分别占78.5%、61.8%,均处于较高水平。随着果园种植时间的增加,果园土壤养分含量均呈直线增加趋势,有效磷和速效钾积累速率显著高于全氮、有机质、有效铁、有效锌的增加速率。土壤养分空间分布特点:土壤养分以0～20 cm积累为主,定位实验31年的果园中20～40和40～60 cm土层土壤有机质、有效磷、速效钾分别相当于0～20 cm的50.8%、59.8%、74.0%和42.3%、27.0%、55.9%。在种植年限为30～40年的果园中,土壤p H明显降低,其0～20、20～40、40～60 cm土层土壤p H值较小于10年果园分别下降1.09、0.41、0.27个单位。主要结论:苹果园土壤有效磷、速效钾积累与树龄呈直线相关,且土壤有效磷、速效钾增幅显著高于土壤有机质、有效铁、有效锌的增幅,是导致土壤养分失衡的主要原因;建议增施有机肥、配合适量铁肥和锌肥平衡果园土壤养分以逐渐提高果园土壤供肥生产能力。     

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。     

土壤养分与澳洲坚果果实内含物间的相关性分析

为了探究澳洲坚果桂热1号种植基地土壤养分与果实内含物之间的相关性,为种植基地科学施肥、提高肥料利用效率提供参考依据。采集广西崇左龙州县、南宁横县、梧州岑溪市3个澳洲坚果种植基地土壤与果实样品,测定土壤养分(全磷、全钙、锌、铁和硒)与果实内含物(钾、钙、镁、铁、锌、磷、硒、可溶性糖、蛋白质、脂肪和氨基酸总量)指标,采用相关性分析方法,筛选影响果实品质的主要土壤养分因子。结果发现,龙州基地全磷含量属于高水平(0.86 g/kg),其余基地属于低水平(0.23～0.30 g/kg);3个基地土壤锌含量都达到很高水平(32.2～177 mg/kg);龙州基地铁含量属于中水平(7.67%),其余基地属于低水平(2.92%～3.16%)。龙州和横县基地均属于富硒土壤(0.84～0.86 mg/kg)。不同基地果实钾含量为370～475 mg/100g,钙含量为42.1～57.5mg/100g,镁含量为93.3～106.3 mg/100g,铁含量为14.0～18.7 mg/kg,锌含量为10.9～12.4mg/kg,磷含量为151～206 mg/100g,硒含量为0.09～0.23 mg/kg,可溶性糖含量为2.78～3.08g/100g,蛋白质含量为8.69～9.33 g/100g,脂肪含量为69.6～83.1 g/100g,氨基酸总量为7.98～8.44 g/100g。其中,龙州基地钙、铁、硒、蛋白质、脂肪和氨基酸总量最高,其余的果实品质指标都是横县基地最高,岑溪基地的果实品质指标都是最低或者居中。果实中蛋白质含量与土壤养分中全磷含量呈极显著正相关(r=1.000),与土壤中全钙、锌和铁含量也达到显著正相关(r=0.998-0.999);果实中可溶性糖含量与土壤中硒含量呈极显著负相关(r=-1.000);果实中氨基酸总量与土壤中硒含量相关系数(0.990)较高;果实中脂肪与土壤中全磷、全钙、锌和铁含量相关系数(0.911-0.933不等)也较高。土壤养分与果实矿质元素含量没有显著的相关性,澳洲坚果果实中的可溶性糖和氨基酸总量主要受土壤硒含量的影响,蛋白质和脂肪主要受土壤全磷、全钙、锌、铁的影响。     

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。     

鲁中碳酸盐岩区土壤硒来源、有效性及影响因素

碳酸盐岩在山东省青州市西南部大面积发育，是土壤母质的重要物源，以该地区土壤作为中心环节，分析了岩石、大气、土壤中的硒及土壤性质，研究了土壤硒的来源、有效性及影响因素。结果表明，土壤全硒含量均值为0.28 mg/kg，以足硒土壤为主，土壤有效硒含量均值为15.03 μg/kg，有效度均值为5.70%，有效硒含量与全硒含量呈显著正相关。岩石硒含量均值为0.035 5 mg/kg，与对应的土壤硒含量呈显著正相关。土壤全硒、有效硒含量与土壤pH均呈显著负相关，与有机质含量均呈显著正相关；有效硒含量与土壤黏粒含量呈显著负相关。大气降尘的硒含量均值为1.77 mg/kg，年沉降通量为0.28 mg/m²，表层土壤硒的年增量为0.000 9 mg/kg，年增长速率为0.33%。鲁中碳酸盐岩区土壤硒含量水平主要受控于母岩，同时大气降尘对土壤硒也有所贡献，土壤理化性质对硒及其有效性影响显著。     

麦草覆盖对果园土壤理化性质影响的研究

对覆草3～5a的苹果园和葡萄园土壤进行采样分析.结果表明;果园覆草后土壤有机质提高0.92～3.33g/kg,全氮和全磷的平均值分别提高0.194mg/kg和0.140mg/kg.土壤容重降低0.068g/cm3,田间持水量增加2.82%,CEC提高1.82cmol/kg,pH变化不显著,对土壤有效养分的影响达极显著水平,影响大小的顺序为有效钾＞有效磷＞有效钾.     

安徽省宁国市土壤和农产品硒地球化学特征及影响因素

以安徽省宁国市全域表层土壤和主要农产品为研究对象,系统采集了6 278件土壤样品和216件农作物样品,研究了土壤全硒含量的分布特征及其主要影响因素,分析了土壤有效硒含量特征和农产品硒含量特征。结果表明:宁国市土壤全硒含量平均值为0.645 mg/kg,富硒土壤样点数和面积占比分别为57.45%、70.30%。土壤硒含量主要受成土母质控制,震旦系和寒武系下统发育土壤硒含量显著高于其他成土母质;不同土地利用方式对土壤硒含量有一定的影响,园地和林地土壤比水田、旱地土壤更易富集硒元素;土壤硒含量与有机质、重金属元素含量存在显著的正相关关系(P0.01),与土壤p H没有显著相关性。土壤有效硒含量平均值为0.023 mg/kg,水稻、山核桃、茶叶中硒含量平均值分别为0.065、0.022、0.074 mg/kg,水稻、山核桃富硒率高达24.04%和54.88%,富硒山核桃具有广阔的开发前景。     

我国主要低产水稻冷浸田养分障碍因子特征分析

研究我国冷浸田主要分布的7个省份冷浸田土壤样品的养分特征,通过与当地高产田土壤养分特征比较发现:我国冷浸田土壤中有机质含量(13.76～21.52g/kg)和全磷含量(2.78～11.36g/kg)总体高于高产田,部分差异显著(P<0.05);全氮含量(1.39～2.24g/kg)总体略高于高产田,但差异不显著(P<0.05);有效锌含量(4.92～11.03mg/kg)总体高于高产田的含量,且差异显著(P<0.05),表明我国冷浸田的潜在生产力比较高。但是,与高产田相比,我国冷浸田土壤pH值显著偏低(4.47～5.32),致毒因子还原态硫含量(296.12～3 069.33mg/kg)和亚铁含量(160.28～3 786.12mg/kg)却显著偏高(P<0.05),同时,部分地区冷浸田土壤速效磷(1.90～30.20mg/kg)和速效钾(1.30～111.70mg/kg)养分显著缺失(P<0.05),表明这几种养分指标是影响我国冷浸田生产力的重要障碍因子,因此,只要有针对性的改良上述冷浸田养分障碍因子,其必将成为我国粮食生产的巨大战略资源。     

Chemical forms and stability of selenium in soil

The chemical forms of selenium (Se) in soils derived from different parent rocks, and the stability of Se species in soils were investigated. Around 40% of the total Se occurred as organic Se on the average. Total selenite content was higher than that of total selenate. The content of organic Se decreased with heating of the soils at high temperatures, and most of it disappeared at heating temperatures above 500°C. However, the results of incubation experiments indicated that Se species were stable in soil, and that their chemical forms did not change appreciably with the variation of soil conditions. In soluble Se, organic Se accounted for about 50%, and in contrast to the total Se, the selenate content was higher than that of selenite.     

Selective determination and formation of elemental selenium in soils

A selective method for the determination of elemental selenium in soil was developed and was applied to the study of elemental selenium in soil. (1) Elemental selenium extracted with carbon disulfide from soil was selectively transformed into selenocyanate ion by reacting with potassium cyanide in carbon disulfide. The selenocyanate ion formed was recovered into an aqueous solution and the amount of selenium in the aqueous solution was determined. This method was specific to elemental selenium and did not interfere with the other selenium compounds and soil components. The method was also highly sensitive and enable to determine more than 0.1 μg kg^-1 of elemental selenium in soil. (2) The formation of elemental selenium was confirmed, when a soil was submerged and the redox potential of the soil decreased. The amount of elemental selenium formed was proportional to the selenite content of the soil, indicating that elemental selenium is transformed from selenite upon its reduction.     

Assessment of seafood processing wastes as alternative sources of Selenium in plant production

Abstract

In some parts of the world, the soil selenium (Se) content is too low to ensure the Se level recommended for human or animal consumption in the crops produced. In order to secure a desired concentration of Se in crops, Se has been applied as mineral fertilizer to agricultural fields. Since only a minor part of the inorganic Se applied is utilized by plants and small increases in Se concentrations in, e.g., drinking water, may be toxic, the method is somewhat controversial. As an alternative to Se-enriched mineral fertilizer, different seafood-processing wastes have been examined as a source for Se in crop production. Both in greenhouse pot experiments and field trials the Se in seafood waste was not plant-available during the first growing season. There was no significant difference between the Se concentration in wheat growing in soil without added Se and in soil receiving Se from seafood waste in amounts ranging from 0.9 to 9 g ha^?1. Neither was any residual effect of Se in seafood waste seen during a second year growth period. Thus, seafood-processing waste cannot be regarded as a potential source of Se in crop production. Possible mobilization of formerly applied Se, as seafood-processing waste or Se enriched mineral fertilizer due to changes in soil redox conditions were examined in a leaching experiment. The mobility of formerly applied Se was generally very low, but the results indicated that under permanently wet soil conditions leaching of Se may occur in plant dormant periods in soils with low organic matter content and high pH.     

Selenium uptake response among selected wheat (Triticum aestivum) varieties and relationship with soil selenium fractions

Some South Dakota soils contain high levels of available selenium (Se) for crop uptake. A field study was conducted to determine if any popular wheat (Triticum aestivum) varieties demonstrate differential Se uptake. A total of 280 samples including eight winter wheat and ten spring wheat varieties were analyzed for grain Se concentration and uptake for two growing years. Soil samples were sequentially fractionated into (1) plant available (0.1?M KH₂PO₄ extractable) and (2) conditionally available (4?M HCl extractable) pools and analyzed separately for total Se. Selenium concentration in wheat grain had a wide variability and the mean value over two years was 0.63?µg?Se?g^?1. Grain Se concentration and Se uptake were not significantly different by wheat varieties tested in this study. Grain Se concentration was significantly correlated with soil Se levels, soil pH, and orthophosphate-P content within a location, but grain Se concentration was strongly influenced by geographical location in which different amounts of soil Se bioavailability occurred.     

桑肠杆菌菌株的富硒特性及其喷施对玉米籽粒的硒素强化

硒是人体必需微量元素之一,对新陈代谢过程有十分重要的促进作用,通过生物强化措施可以增加人体对硒素的补充。该研究利用从植物内生菌中筛选出的一株具有将无机硒转化成生物利用率更高的有机硒的菌株IX+2 2,测定其16S r RNA基因序列,鉴定该菌株为桑肠杆菌(Enterobacter mori)。该文研究不同的硒含量、加硒时间与不同培养收集时间对菌株IX+2 2硒素转化率的影响。结果表明,培养基中硒含量越高,菌株IX+2 2胞内有机硒含量越高,硒素转化率越高,但达到某一个峰值后又开始下降;在对数生长期加硒有利于菌株IX+2 2的生长和对无机硒的转化;菌株培养24 h时收集硒素转化效果最好,继续培养菌体生长减弱。同时针对菌株对玉米籽粒富硒的强化效应做了进一步验证。该菌株对玉米籽粒富硒的强化作用表明:同等亚硒酸钠用量条件下,亚硒酸钠喷施处理后玉米籽粒中硒含量达到228.58μg/kg,而富硒微生物菌剂处理后籽粒中硒含量达到378.89μg/kg,是前者的1.66倍,富硒IX+2 2菌剂的富硒效果优于喷施亚硒酸钠溶液。该研究结果可为玉米籽粒的硒素强化提供理论支撑。     

Biofortification of wheat cultivars with selenium

ABSTRACT

Biofortification experiments with three winter wheat cultivars treated with sodium selenate through foliar- and soil-fertilisation were conducted at two locations in Croatia and Serbia in two consecutive years to increase the selenium (Se) concentration in bread-making wheat grain. The treatments were: (a) 5?g?ha^?1 Se foliar-, (b) 10?g?ha^?1 Se foliar- and (c) 10?g?ha^?1 Se in soil surface-application and they were compared with (d) control. Both Se foliar- and soil-fertilisation increased the Se concentration in grains from 2.6- to 4.6-fold. The concentration in grain was highest with Se foliar-fertilisation of 10?g?ha^?1 and it was increased by 29–32?µg Se kg^?1 dry weight for each gram of Se applied per ha. The wheat cultivars differed in grain yield and Se uptake (g?ha^?1 Se). However, on average, there were no differences between wheat cultivars with respect to Se grain concentrations. Agronomic use efficiency (by grain) was significantly higher for Se foliar- (19%) than for soil-fertilisation (13%). It can be concluded that agronomic biofortification of winter wheat can be effective in increasing Se grain concentration, where the efficiency depends on the rate of Se applied, application method and local environmental conditions rather than on cultivar differences.     

不同用量腐植酸对土壤有效硒含量和硒的形态以及大蒜硒吸收的影响

采用室内土培和网室盆栽的方法,研究了不同用量的腐植酸对土壤有效硒含量和硒形态以及大蒜硒吸收规律的影响。结果表明:土壤有效硒含量随着腐植酸用量的提高而增加,20%OM处理的土壤有效硒含量(43.3~50.6μg·kg~(-1))10%OM(37.6~48.8μg·kg~(-1))5%OM(36.0~44.1μg·kg~(-1))CK(33.0~41.5μg·kg~(-1))。可溶态硒与土壤有机质含量的关联度最大(关联系数为0.821),其次为有机硫化物结合态硒(关联系数为0.693),铁锰氧化物结合态硒关联度最低(关联系数为0.482)。随着腐植酸用量的增加,土壤有机质含量得到相应提高,土壤中有机质的含量与可溶态硒、可交换态及碳酸盐结合态硒和有机硫化物结合态硒呈显著正相关,其相关系数分别为0.963、0.962和0.906,而与其他形态的硒相关性不明显。大蒜各部位干重的硒含量为根(0.167~0.653 mg·kg~(-1))茎(0.114~0.326 mg·kg~(-1))叶(0.056~0.086 mg·kg~(-1)),且4个处理大蒜鳞茎鲜重的硒含量为0.018~0.110 mg·kg~(-1),均达到了富硒食品标准(HB001/T—2013)。     

马铃薯硒营养强化技术研究进展

硒是人体必需的微量元素,马铃薯是世界上第4大主粮作物,施用硒肥是生产富硒马铃薯的主要途径。本文介绍了马铃薯硒营养强化技术研究进展,阐述了硒在马铃薯植株内的一般累积分布规律,硒肥对马铃薯生长发育、产量和品质的影响;介绍了马铃薯生长过程中硒营养强化的生理遗传机制等内容;总结了近年来马铃薯富硒栽培技术和新型肥料研发情况;指出绿色环保、低廉高效的生物有机硒肥、缓释硒肥将是未来的发展方向。     

叶面喷施硒肥对小麦籽粒及面粉硒含量的影响

为了探明叶面喷施硒肥对小麦籽粒及制粉各粉路硒含量的影响,本研究选用4个小麦品种,在拔节和抽穗期分2次喷施0.017%亚硒酸钠叶面肥,并对成熟期籽粒进行制粉,分析各粉路的总硒、无机硒和有机硒含量。结果表明,叶面喷硒对小麦籽粒和面粉的总硒、有机硒和无机硒含量的影响存在品种间差异。喷施硒肥后,4个小麦品种籽粒的总硒含量提高了26.4~35.8倍,但小麦籽粒产量无显著变化。皮磨粉、心磨粉、统粉、小麸和大麸5种粉路中,小麸的总硒含量最高,其次为大麸,皮磨粉、心磨粉和统粉的总硒含量较低。与硬质小麦相比,软质小麦出粉率低,面粉的总硒量损失较多。经制粉,对照和喷硒样本的总硒积累量分别损失52.97%~69.28%和36.73%~44.51%。对照样本中,各粉路的有机硒含量略高于无机硒含量;而喷硒处理样品中,除宁麦20的小麸外,各粉路的有机硒含量均略低于无机硒含量。本研究揭示了制粉粉路硒分布规律,这对于富硒小麦的加工利用具有重要的指导作用。     

施用硒矿粉对烟苗光合特性、成苗素质及硒积累的影响

通过在营养液中加入硒矿粉的方法,研究了不同硒矿粉用量对烟苗光合特性、成苗素质及硒积累的影响。结果表明,苗期施用硒矿粉能促进烟苗生长,随着施用量的增加,烟苗的叶绿素、可溶性糖、根系活力和硒含量明显增加。低用量的硒矿粉提高了烟苗的净光合速率(Pn),可能增加了叶绿素含量和减少了气孔限制是重要原因;高用量的硒矿粉导致烟苗Pn下降,主要是由气孔因素决定的。在本试验条件下,适宜的苗期硒矿粉用量为24.6 kg/hm2。