瘤胃液对全株甜高粱青贮质量的影响

甜高粱是一种重要的能源作物,为实现长时间贮存并提升糖化效率,该研究分析了瘤胃液不同添加量对全株甜高粱青贮品质和酶解糖化效果的影响.设置R1、R3、R5和R7共4个瘤胃液处理组(添加量依序分别为1、3、5和7 mL/100 g原料)和1个对照组(CK,等量蒸馏水),考察了瘤胃液不同添加量对全株甜高粱青贮过程中有机组分、发...     

土壤中铜、铅、锌相对浓度比稳定性的研究

铜、铅、锌均与硫元素有较强的亲和力,从而使它们具有相似的地球化学性质,并在环境自然体中紧密共生.人们已经认识了铜和锌是人体必需的微量元素,而铅是有害的元素,它们的环境与生物地球化学行为,直接影响到人体的健康.因此,表生环境中的铜、铅、锌始终是研究的热点.     

氮肥用量和喷施锌钾肥对小麦籽粒锌含量及生物有效性的影响

[目的]小麦籽粒锌(Zn)含量普遍较低,在没有外源锌施用措施下难以满足以小麦为主食人群健康所需.探索提升小麦籽粒Zn含量,尤其是其加工产品面粉Zn含量和Zn生物有效性的农艺措施,具有实际重要的意义.[方法]于2013、2014年分别在陕西杨凌示范区和三原试验站进行小麦田间试验,两地均为潜在缺锌石灰性土壤,DTPA-Zn...     

棉(Gossypium hirsutum L.)纤维发育相关酶和纤维比强度对棉铃对位叶氮浓度变化的响应研究

于2008～2009年在长江流域下游棉区,选用纤维比强度差异明显的德夏棉1号（平均比强度26.2 cN/tex）、科棉1号（平均比强度35 cN/tex）和美棉33B（平均比强度32 cN/tex）为试验材料,设置不同施氮量以形成不同的棉铃对位叶氮浓度,研究了棉铃对位叶氮浓度对纤维发育过程中关键酶（蔗糖酶、蔗糖合成酶、磷酸蔗糖合成酶、-1, 3-葡聚糖酶）活性及纤维比强度形成的影响。结果表明,棉铃对位叶氮浓度随施氮量的增加而上升,随花后天数的变化符合幂函数方程YN＝t-［YN:棉铃对位叶氮浓度（%）;t:花后天数（d）;、为参数］。在花后同一时期,纤维发育关键酶活性和纤维比强度均随棉铃对位叶氮浓度的上升呈先升后降的趋势,可用抛物线方程Y=ax2+bx+c拟合［Y:酶活性或纤维比强度（cN/tex）;x:叶片氮浓度（%）;a、b、c为参数］。表明在纤维发育过程中,棉铃对位叶氮浓度显著影响纤维中相关酶活性和纤维比强度的形成,各指标所对应的最佳棉铃对位叶氮浓度差异较小;因此,通过调节对位叶氮浓度可调控相关酶活性达到最优以及棉花高强纤维的形成。在本试验条件下,中部棉纤维发育所需的最佳对位叶氮浓度动态变化方程分别为:NDexiamian1=7.2841t-0.2771(R2=0.9860＊＊);NKemian1=7.1807t-0.2989(R2=0.9879＊＊);NNuCOTN33B=7.1467t-0.2819(R2=0.9755＊＊)。     

绿环生物套餐肥在茎瘤芥(榨菜)上的应用

茎瘤芥,俗称青菜头,为世界三大名腌菜之一的涪陵榨菜的主要原料作物,目前涪陵种植面积已达3.2万hm2以上。长期以来,茎瘤芥生产上,菜农多以施氮、磷等化学肥料,极少施用有机肥,致使土壤一定程度上存在板结、生产环境日趋恶化。为了从根     

深沟排水对茎瘤芥根肿病的控害技术研究

在重庆市涪陵区研究了深沟排水对茎瘤芥根肿病的控害效果。结果表明:(1)深沟排水对茎瘤芥根肿病有一定的控制效果,其控害程度因沟的深浅组配及开挖宽度的不同有显著差异;(2)不同的挖沟设计间的减产植株率及绝收植株率差异明显。由此提出病区最佳排水沟开挖设计为3.0m×1.5m×3.0m(深—浅—深)。     

碳酸钙含量对土壤中锌有效性和小麦锌铁吸收的影响

石灰性土壤中高碳酸钙(CaCO3)含量是引起作物缺Zn的重要原因之一.本研究设置了由低到高的土壤CaCO3含量梯度,以探讨CaCO3对土壤有效Zn含量、两种基因型小麦(远丰998,中育6号)生长发育及Zn、Fe营养的影响.结果表明,与不施Zn相比,施Zn使土壤有效Zn含量增加了3.22倍; 高含量CaCO3使土壤有效Zn含量有所降低,新施入的有效态Zn仅有1.3%被小麦吸收,大部分则转化为无效态Zn;CaCO3含量达到111.8 g/kg时,可明显抑制小麦对Fe的吸收,进一步提高CacO3含量抑制作用有所减弱;两种小麦基因型生长存在明显的差异,中育6号的根冠比和分蘖数都显著高于远丰998;施zn可显著增加小麦Zn含量和吸收量, CaCO3含量达到111.8 g/kg可显著降低小麦根的Zn含量,对其他部分影响不明显;此外,施Zn可增加叶片的Fe含量和转运率.     

三江平原白浆土中Fe、Mn、Cu和Zn生物有效性的研究

在三江平原上,测定 42 个小区中玉米、大豆、小麦籽实 Fe、Mn、Cu 和 Zn 含量和土壤中各形态 Fe、Mn、Cu 和Zn含量.通过相关分析和通径分析,探讨了土壤中各形态Fe、Mn、Cu 和 Zn 的生物有效性,旨在为该地区合理施用微量元素提供科学依据.试验结果表明,玉米、大豆和小麦籽实含 Fe、Mn、Cu 和 Zn 量与土壤中有效态和交换态 Fe、Mn、Cu和Zn含量呈显著或极显著正相关.有机态 Fe、Mn、Cu 和 Zn含量与玉米、大豆和小麦籽实Fe、Mn、Cu 和 Zn含量也有很好的相关关系.交换态对有效态 Fe、Mn、Cu 和 Zn 影响最大,其次是有机质结合态.铁锰氧化物结合态 Fe、Cu 对有效态 Fe、Cu 及碳酸盐结合态 Mn、Zn 对有效态 Mn、Zn 具有一定正效应.而残留态 Fe、Cu 对有效态 Fe、Cu 和铁锰氧化物结合态 Mn 对有效态 Mn 产生负效应.     

蚯蚓对污染土壤中黑麦草和印度芥菜吸收累积锌的影响

以长江冲积物形成的高沙土为供试土壤,分别加入4个浓度的Zn(100、200、300、400 mg/kg)以模拟Zn污染土壤,设置了接种蚯蚓(Pheretima sp.)处理与不加蚯蚓的对照处理,并种植黑麦草和印度芥菜,以研究蚯蚓活动对不同植物吸收、累积Zn的影响.结果表明:除低浓度Zn处理外(Zn≤100 mg/kg),蚯蚓活动明显增加了污染土壤的DTPA提取态Zn含量,进而促进植物对Zn的吸收.蚯蚓活动同时提高了印度芥菜和黑麦草地上部和地下部生物量及植株体Zn浓度,促进了植物对土壤Zn的吸收.加入蚯蚓后印度芥菜和黑麦草中Zn总累积量较无蚯蚓对照分别提高了57.8%～131.6%、51.4%～150.5%.两种植物相比,印度芥菜植株Zn浓度明显高于黑麦草,但由于印度芥菜生物量低,不论是否接种蚯蚓,其Zn累积量均低于黑麦草(未加Zn处理除外).黑麦草生长条件要求不高、可多次刈割,因而具有很大的修复中、轻度Zn污染土壤的潜力.     

亮蓝在喀斯特黑色石灰土和红壤中流动滞后性的研究

亮蓝已被普遍接受作为野外可视化土壤水分运移路径的染色示踪剂,但不同土壤对亮蓝的吸附会对其流动性造成不同程度的迟滞,进而影响亮蓝的染色效果。以石林喀斯特地区黑色石灰土和红壤为研究对象,通过一系列亮蓝浓度梯度对照试验,采用相对迟滞系数作为量化指标,探究亮蓝示踪黑色石灰土和红壤的水分运移规律和适宜浓度。结果表明:(1)亮蓝浓度不影响水的运移;(2)亮蓝在两种土壤中的流动滞后性均呈现随亮蓝浓度增加而减小的趋势,浓度超过10g/L的亮蓝在黑色石灰土中的流动深度基本跟水流一致,浓度超过50g/L的亮蓝在红壤中流动滞后性趋于稳定但仍明显。试验证明示踪南方喀斯特地区土壤水分运移应选用高浓度的亮蓝染色剂。     

(土娄)土剖面CO2浓度的动态变化及其受环境因素的影响

CO2是土壤空气的重要组成,土壤空气CO2浓度一般高于大气几倍到数十倍,甚至上百倍[1].     

利用15N示踪技术研究尿素在人工瘤胃中的代谢

通过人工瘤胃短期发酵,采用4×2析因完全随机试验设计,利用15N标记尿素代替日粮粗蛋白的0%、10%、20%、40%,分别发酵24和48h,研究日粮不同尿素添加量对瘤胃发酵参数的影响及其在瘤胃中的代谢.结果表明:不同尿素添加量和发酵时间对瘤胃pH影响不显著(P＞0.05),添加尿素处理的瘤胃液氨态氮浓度在发酵48h时显...     

土壤中Cd、P、Zn含量对水稻产量和植株中矿物浓度的影响

在温室中进行了剖析添加的Cd、P、Zn对稻谷产量、植株和稻草中的矿物含量以及糙米中Cd的浓度的研究。P增加了稻谷和植株产量,而Cd、Zn和P-Zn的交互作用使其降低。稻谷和植株产量有类似的线性回归方程式,其稻谷的线性回归方程为: Y=17.24+0.0466(P)-0.1850(Cd)-0.1115(Zn)-0.0005(P-Zn) 其R²=0.97^**,式中Y为稻谷产量(克/株);P为添加的P浓度(毫克/公斤);(Cd)为添加的Cd浓度(毫克/公斤);(Zn)为添加的Zn浓度(毫克/公斤);(P-Zn)为P和Zn的交互作用。所有处理均明显地影响着稻草中矿物元素的含量。粕米中的Cd浓度随着添加的Cd、P、Zn浓度的增加而增加;但多元回归分析表明只有Cd的影响是显著的。粕米中Cd的浓度与收获时用0.05M HCI所提取的风干土中的Cd浓度有极显著相关性(Y=0.75^**).对糙米中Cd浓度的评价进行了简要的讨论。     

固体废弃物及土壤中磷的形态分析技术

畜禽粪便等固体废弃物及土壤中磷的形态分析对于管理固体废弃物、提高磷素利用率、减少磷素流失风险具有重要意义。自20世纪初以来,已提出多种固体废弃物及土壤中磷素形态分析的方法,包括化学分级、酶水解法、红外光谱(FT-IR)、X射线衍射(XRD)、31P核磁共振(31P NMR)、X射线吸收近边结构(XANES)等。本文系统总结了一些固体废弃物及土壤中磷素形态分析的方法,比较了其特点,指出只靠单一的方法并不能很好的鉴定固体废弃物及土壤中磷素的形态,必须综合考虑运用多种方法,从而为磷素形态分析提供方法选择的依据,同时为进一步发展固体废弃物及土壤中磷素形态分析新技术奠定基础。     

塿土剖面CO2浓度的动态变化及其受环境因素的影响

CO₂是土壤空气的重要组成,土壤空气CO₂浓度一般高于大气几倍到数十倍,甚至上百倍^[1]。土壤空气中CO₂主要来源于土壤呼吸,其浓度主要决定于生物因素(植物根系、土壤微生物活性等)和环境因素(土壤温度、含水量等)^[2～4]。土壤空气CO₂浓度可以反映和影响土壤向大气释放CO₂的通量^[4,5],同时对植物根系生长发育、土壤微生物活动和各种养料物质转化也有很大影响^[1]。研究了解土壤空气CO₂浓度剖面分布、季节动态及其影响因素,有助于人们认识土壤中CO₂产生、累积、输运以及向大气排放的生物和物理过程,制定和实施合理的农作措施以改善作物生长环境和减少土壤向大气排放的CO₂。国外已在森林、草地和农田土壤上开展了较长时间的土壤空气CO₂浓度观测研究^[4~7],但我国的研究和报道很少^[8,9]。本文通过土壤剖面不同深度CO₂浓度的定位观测,初步揭示了土剖面CO₂浓度的分布特征、季节动态及其受水热条件的影响。     

VARIATIONS IN SULPHUR AND NITROGEN FOLIAR CONCENTRATION OF DECIDUOUS AND CONIFERS VEGETATION IN SLOVAKIA

The foliage contents of S_total and N_total were determined in 405 Permanent monitoring plots in four National Parks and sixteen Landscape Protection Areas and were compared with 1483 Permanent monitoring plots on Slovakia. The foliage content of S ranged from 0.72 to 6.77 g kg^-1 in hardwoods and from 0.98 to 4.3 g kg^-1 in softwoods. A critical increase was determined in one National Park and in four Landscape Protection Areas. The foliage content of N ranged from 9.7 to 48.7 g kg^-1 in softwoods, and from 7.8 to 51.4 g kg ^-1 in hardwoods. An insufficient level of N was determined in one Landscape Protection Area and a critical increase in four Landscape Protection Areas. The sulphur to nitrogen ratio ranged from 0.08 to 0.176 in softwoods, and from 0.078 to 0.253 in hardwoods. The foliage surface on hitherto explored four National Parks and sixteen Landscape Protection Areas in network 4 × 4 km was covered by all categories of rigid fall-out particles. Fly-ash from coal combustion were observed each of National Parks and Landscape Protection Areas by scanning electron microscopy. Mycelia and spore, mineral matters, sand and soil particles were present on all National Parks and Landscape Protection Areas. Particles derived from aluminium production were observed at three Landscape Protection Areas. Particles derived from cement production and from lime works were observed at two National Parks and six Landscape Protection Areas. Particles derived from ferrous metals industry were observed at each of National Parks and Landscape Protection Areas and particles typical for other technologies were present in three of National Parks and twelve Landscape Protection Areas.     

SILICON NUTRITION AND PHYTOPHTHORA DRECHSLERI INFECTION EFFECTS ON GROWTH AND MINERAL NUTRIENTS CONCENTRATION,UPTAKE, AND RELATIVE TRANSLOCATION IN HYDROPONIC-GROWN CUCUMBER

A hydroponic experiment was performed to investigate silicon (Si) and Phytophthora drechsleri root rot effects on growth and tissue partitioning of Si, zinc (Zn), iron (Fe), and manganese (Mn) in two cucumber cultivars (Cucumis sativus L. cvs. ‘Dominus’ and ‘Super Dominus’). Root length, plant height, and root fresh weight were significantly decreased by P. drechsleri, which were all significantly alleviated by 1.0 mM Si. Increasing Si level in the nutrient solution was accompanied with its enhanced uptake by cucumbers. Plants infected with P. drechsleri transported lower Mn to shoot than non-infected plants. Influence of P. drechsleri infection on root Fe concentration was dependent on cucumber cultivar while a decrease in root Zn concentration was found in infected cucumbers. Silicon nutrition increased Zn and Fe uptake in both cucumber cultivars. It is suggested that Si nutrition improved the crop growth, particularly under biotic stress, and hereby, increased micronutrients uptake by cucumber.     

仿刺参体腔液补体类似物化学发光免疫检测

首次应用酶联化学发光免疫检测(Chemiluminesent Immunoassay,CLIA)技术测定仿刺参体腔液补体类似物AjC3和AjC4。羊抗人C3、C4抗体吸附到经过紫外线处理的聚苯乙烯管内,采用辣根过氧化物酶(HRP)标记抗体。过氧化氢和鲁米诺为辣根过氧化物酶的底物。捕获抗体包被最适浓度为1μg/ml,免疫反应20℃孵育2h达到平衡。HRP-IgC3、IgC4抗体复合物适宜稀释度为1:2000,HRP-IgC3I、gC4抗体复合物4℃下保存8d性能稳定,室温下5d内性能稳定。标准品浓度在0.1～10ng/ml范围内时与化学发光值之间具有良好的线性相关性,检测灵敏度为0.1ng/ml。结果表明应用酶联化学发光免疫检测技术能够检测到仿刺参体腔液中含有补体类似物,AjC3含量为6.58±1.4μg/ml,AjC4含量为0.67±0.3μg/ml。     

RELATIVE EFFECTS OF TRACTOR WEIGHT AND WHEEL-SLIP IN CAUSING SOIL COMPACTION

The results presented are from field studies in which soil compaction was measured under tractors working with different wheel loads and levels of wheel-slip. Wheelslip proved to be more important in causing compaction than additional wheel loading, and this effect was more pronounced for more powerful tractors. In most agricultural circumstances the aim is to secure the best compromise between weight and slip as alternative means of achieving greater work output from tractors. The results indicate that in situations where there is a need to avoid compaction, particular attention should be given to providing sufficient wheel loading and the possibility of moving faster to take up more power at lower slip. For the range of soil moistures encountered sinkage was the most convenient and satisfactory method of assessing total reduction in porosity, and differentiated between treatments better than any of the other methods (see below) apart from water-entry rates. Measurement of soil density at three levels to 15 cm depth accounted for less than 50 per cent of the loss of porosity estimated from sinkage and the method did not detect differences due to treatment. Shear strength measured at one depth (3.5 cm) differentiated between treatments, but penetration resistance at 7.5 cm did not. Water-entry rates sensitively detected treatment differences but the method was too time-consuming for comparison of all treatments. The efficiency of traction of four- and two-wheel-drive tractors was measured at intervals during the winter on a clay loam and the results related to surface moisture contents. After a steep reduction in efficiency, when the soil returned to field capacity, subsequent changes in efficiency were small.