磷钾肥对云南旱作马铃薯产量和养分吸收的影响--测试文章

在云南省曲靖地区的低肥力和中高肥力试验地分别开展旱作马铃薯的田间小区试验,研究磷钾施用量对马铃薯生物量、养分利用、产量和经济效益的影响。结果表明：相同施肥量的条件下,中高肥力试验地的东山组马铃薯产量远高于低肥力的越州组,产量相差10 305.00～20 140.20 kg·hm^-2;越州组NP2K3(N,150 kg·hm^-2; P₂O₅,90 kg·hm^-2; K₂O, 405 kg·hm^-2)处理产量产值最高,NP2K1(N,150 kg·hm^-2; P₂O₅,90 kg·hm^-2; K₂O, 135 kg·hm^-2)处理净收益最高; 东山组NP2K2(N,150 kg·hm^-2; P₂O₅,90 kg·hm^-2; K₂O, 270 kg·hm^-2)处理产量、产值及净收益均是最高; 两组试验的马铃薯干重变化趋势相似,NP2K2处理的干重积累量较多,无钾无磷处理干重积累少;马铃薯体内累积K最多,其次为N,最后为P, NPK养分吸收积累的高峰期在马铃薯块茎膨大期到淀粉积累期; 东山组的马铃薯PK利用效率明显高于越州组。NP1K2(N,150 kg·hm^-2; P₂O₅,45 kg·hm^-2; K₂O, 270 kg·hm^-2)处理的P肥利用率和P素农学效率较高,P肥利用率和P素农学效率都有随施P量增加而降低的趋势。NP2K1处理的K肥利用率和K素农学效率最高,K肥利用率和K素农学效率均有随施K量增加而降低的趋势。     

不同耕作覆盖措施下延收对春玉米产量及籽粒品质的影响

选用5种耕作覆盖方式和7个采收时期研究延收对籽粒产量、千粒重、籽粒蛋白质、脂肪、淀粉含量及其对应的产出量的影响，为玉米获得高产优质提供依据。结果表明：适时延收可使玉米产量及主要营养成分产出量明显增加，延收15 d，产量增幅为10.19%～15.62%，千粒重增幅为14.70%～20.39%；籽粒蛋白质含量增加0.26%～1.29%，产出量增加117～230 kg·hm^-2；脂肪含量增加0.05%～0.40%，产出量增加54～78 kg·hm^-2；淀粉含量虽然降低0.5%～4.9%，但产出量仍然增加340～773 kg·hm^-2。黄土高原地区春玉米延收15 d具有明显的增产和提高籽粒品质产量的效果，但增幅因耕作和覆盖方式不同而存在差异。     

近50年河南省夏玉米生产潜力及产量差时空变化特征--测试文章

利用河南省96个县1961—2010年气象资料和夏玉米实际产量,采用逐步订正模型,计算了近50年河南省夏玉米光温生产潜力和气候生产潜力,分析了光温生产潜力与气候生产潜力、光温生产潜力与实际产量两种产量差的时空变化特征。结果表明：(1) 光温生产潜力由北向南、由东向西递减,近50年呈极显著下降趋势,全省平均每10 a减少696.8 kg·hm^-2,北、中大部分站点和南部的部分站点下降幅度较大。(2) 气候生产潜力南部高于北部、东部高于西部,近50年变化趋势不明显。光温生产潜力与气候生产潜力之间的产量差呈极显著下降趋势,平均每10 a减少958.7 kg·hm^-2。(3) 夏玉米实际产量极显著增加,光温生产潜力与实际产量之间的产量差极显著下降,平均每10 a减少1 718.0 kg·hm^-2,但71.9%的站点产量差大于24 000 kg·hm^-2,产量潜力仍有较大提升空间。降水是制约河南省西部夏玉米产量的主要因素,可通过灌溉提高产量;后期热量不足影响北部玉米产量进一步提高,选用中早熟品种和改进栽培技术是提高产量的途径;东部可通过增加灌溉面积、选用优良品种和科学施肥等措施缩小产量差。     

不同秸秆还田量对旱地全膜双垄沟播土壤水分及玉米生长的影响

在通渭半干旱区通过试验研究了不同秸秆还田量对全膜双垄沟播玉米生长形状、土壤水分状况及产量的影响。试验设计了3个还田量梯度,即玉米秸秆按6 000 kg·hm^-2（低量还田处理）、9 000 kg·hm^-2（中量还田处理）、12 000 kg·hm^-2（高量还田处理）整秆还田,不还田处理作为对照。结果表明,在生育前期时,0～200 cm土壤水分呈现出还田量越高土壤含水量越高的趋势,在出苗期最为明显,高、中、低还田量处理较对照土壤含水量分别高出6.07%、1.24%、0.31%,而在抽雄期后,则表现为低量还田处理>中量还田处理>不还田处理>高量还田处理,叶面积大小表现为高量还田处理>中量还田处理>低量还田处理>不还田处理。耗水量表现为低量还田处理<中量还田处理<不还田处理<高量还田处理。产量及水分利用效率以6 000 kg·hm^-2还田量处理最高,适宜在半干旱旱作区进行推广。     

不同密度条件下旱地胡麻灌浆特性研究--测试文章

在定西干旱生态条件下,以陇亚10号胡麻为材料,研究了密度对籽粒灌浆特性和农艺性状的影响。结果表明：随着种植密度的增大,胡麻分枝数、蒴果数减小,株高波动性变化;胡麻籽粒干物质积累过程呈“S”型曲线,可用Logistic模型进行模拟,相关系数达0.99以上,花后6～31 d籽粒干物质积累速度最大; 胡麻最大灌浆速率、平均灌浆速率和灌浆持续期均受种植密度的影响,处理间平均灌浆速率差异明显,其中以600 万株·hm^-2的平均灌浆速率最高,1 050 万株·hm^-2的平均灌浆速率最低;不同密度处理间百粒重和产量存在显著性差异,600 万株·hm^-2处理的百粒重和籽粒产量最大,显著高于1 200 万株·hm^-2处理。说明在实际生产中要根据不同胡麻品种类型选择最佳的种植密度。     

秸秆还田下减量施氮对作物产量及养分吸收利用的影响--测试文章

秸秆还田条件下,采用多年田间定位试验研究了N肥减量施用对作物产量、养分吸收利用以及土壤表观N平衡的影响,旨在为关中小麦/玉米一年二熟轮作区合理施用N肥提供依据。结果表明：与常规施N处理(玉米季施氮187.5 kg·hm^-2,小麦季施氮150 kg·hm^-2)相比,2008—2011年三年中,15%减N、30%减N两个处理均未显著降低作物籽粒与秸秆产量;2010—2011年生长季中,15%减N处理降低了作物秸秆N、P、K周年总吸收量,增加了籽粒N、P、K周年总吸收量,其中籽粒P周年总吸收量增加达显著性水平;30%减N处理显著降低了籽粒N和秸秆N、K周年总吸收量,降幅分别为12.9%、41.9%、18.5%,在小麦收获后,30%减N处理的N素盈余量只有11.3 kg·hm^-2,有潜在缺N危险。综合考虑产量、养分吸收利用及土壤表观N平衡,在秸秆还田条件下,15%减N处理的施N量（即玉米季施氮159 kg·hm^-2,小麦季施氮127.5 kg·hm^-2）为本地区最佳N肥用量。     

中度盐碱地氮、磷肥对蓖麻生育特性和产量的影响

以淄蓖8号为试验品种,研究了中度盐碱地蓖麻在不同施氮量和施磷量条件下的生长特性、干物质积累、产量构成和产量。结果表明,氮肥、磷肥和两者互作对各时期主茎真叶数的影响不显著,氮肥、磷肥和两者互作从蕾期开始对株高和地上部干重的影响达显著或极显著水平,从苗期开始对叶干重和茎干重的影响达显著或极显著水平,对花序干重的影响达显著或极显著水平;氮肥对每株穗数的影响达到显著水平,磷肥及二者互作的影响未达到显著水平;氮肥、磷肥及二者互作对每穗粒数、百粒重和籽粒产量的影响达到显著或极显著水平;开花期、花后和灌浆成熟期群体地上部干物质积累与籽粒产量均呈显著线性正相关关系,提高开花后干物质的积累有利于籽粒产量的提高。在本试验条件下,施氮量225 kg·hm^-2、施磷量90 kg·hm^-2,苗期和蕾期各施用氮、磷肥的50%获得的籽粒产量最高,达3　568.4 kg·hm^-2。     

屠宰场废弃物堆肥对苜蓿生长和碱化土壤肥力指标的影响

对屠宰场猪、牛、羊废弃物堆肥施入退化土壤后作物生理指标、土壤肥力指标和微生物区系变化进行系统研究。结果表明：施用废弃物堆肥明显提高了苜蓿出苗率，并缩短了出苗时间，但不同种类、不同施用量（22.5 t·hm^-2、30.0 t·hm^-2和37.5 t·hm^-2）废弃物提高的幅度不同。苜蓿鲜生物量随着废弃物施用量的增大而增加，其中羊废弃物施用量为37.5 t·hm^-2的处理最大，为11.95 g·plant^-1，不施用废弃物的处理鲜生物量最小，其最大值为10.26 g·plant^-1；施用猪废弃物30.0 t·hm^-2的处理其干生物量最高（3.91 g·plant^-1）。施用屠宰场废弃物堆肥后土壤有机质及养分都有不同程度的增加，如10月中旬土壤有机质和速效钾含量增幅略低，分别为9.92%～27.12%和5.77%～34.03%，碱解氮和速效磷增幅分别为11.79%～47.66%和16.92%～44.97%。猪废弃物施用量为37.5 t·hm^-2的处理细菌数量在8月底达到3.98×10⁷ cfu·g^-1，羊和牛废弃物相同时期相同用量条件下细菌数量相近，一般废弃物施用量越大土壤中细菌、真菌和放线菌数量也越多。     

水溶性金属卟啉的合成、表征及其清除有毒活性氧的研究

目的合成并结构表征了4种水溶性金属卟啉配合物［5，10，15，20-四［4-(4′-吡啶-1)丁氧基苯基］金属卟啉溴化盐［锌卟啉(I)、铜卟啉(II)、锰卟啉(III)和钴卟啉(IV)］，作为抗活性氧(O^-₂，H₂O₂，HO·)模拟酶。方法 核黄素-蛋氨酸光照测其清除O^-₂作用，H₂O₂氧化Vit C法测其催化H₂O₂的分解，Fenton-苯甲酸钠荧光法测其对HO·清除作用，小鼠肝匀浆法测其抗脂质过氧化作用。结果1.0×10^-5~1.0×10^-6 mol·L^-1均具有良好的清除O^-₂作用；1.5×10^-6~1.0×10^-6 mol·L^-1均具有分解H₂O₂作用；2.0×10^-8~1.0×10^-8 mol·L^-1均具有清除HO·的功能；1.0×10^-7 mol·L^-1均可使脂质过氧化产物明显减少。结论合成4种水溶性金属卟啉配合物可作为抗多种活性氧(O^-₂，H₂O₂，HO·)模拟酶。     

Pb2+-NaOH介质中蛋白质水解物的极谱吸附波及其应用Pb2+-NaOH介质中蛋白质水解物的极谱吸附波及其应用

目的建立一种快速、简便、灵敏的蛋白质含量测定的新方法。方法含有巯基或二硫基的蛋白质与0.5 mol·L^-1氢氧化钠、1.5×10^-4 mol·L^-1 Pb²⁺和0.02%四丁基碘化铵的混合溶液在沸水浴中反应5 min，采用单扫描极谱法，测定-0.66 V(vs SCE)处一价导数波高。结果牛血清白蛋白（BSA）、人血清白蛋白（HSA）的浓度在7.5×10^-10～3.0×10^-7 mol·L^-1与其波高呈线性关系，BSA和HSA检测限均为3.0×10^-10 mol·L^-1；溶菌酶(Lyso)的浓度在1.4×10^-8～1.3×10^-6 mol·L^-1与其波高呈线性关系，Lyso的检测限为7.0×10^-9 mol·L^-1。结论该方法取样量少、体系简单、灵敏度高，可用于人血清样品中蛋白质含量的测定。     

Incidence of contamination with aflatoxin in precooked corn flour, corn grain and cracked corn

A study was carried out to determine the presence and content of aflatoxins in 90 samples of precooked corn flour (23 yellow and 67 white), 40 samples of corn grain (30 yellow and 10 white), and 30 samples of yellow cracked corn. No aflatoxin was detected in white corn grain. The other investigated samples showed the following rates of contamination: yellow corn grain, 10%, ranging from less than 5 to greater than 10 ppb; yellow cracked corn, 16.6%, ranging from less than 5 to greater than 20 ppb; and white corn flour, 6%, and yellow corn flour, 87%. Of 14 aflatoxin positive samples tested, only 1 contained more than 20 ppb, the administrative guideline established by the US Food and Drug Administration (FDA). The results of this survey do not appear alarming because of the relatively low incidence and low levels of aflatoxin detected. However, since Venezuela is a big consumer of corn and corn-derived products, a more detailed investigation is suggested to establish the realistic levels of aflatoxin in these commodities.     

Extraction and determination of phytosterols from corn oil foots

By saponification and extraction of corn oil foots abandoned as waste during oil refining, a mixture of phytosterols was obtained, and its major components were determined as β-sitosterol, campesterol and stigmasterol by gas chromatographic analysis. The mixture is very cheap and regarded as an excellent substrate for direct fermentation of C-17 keto steroid intermediate for various steroid pharmaceuticals.     

Toxigenic fungi and mycotoxins in mature corn silage

To investigate the exposure of livestock and farm workers to mycotoxins during the last months of silage use, the mycoflora and the mycotoxins in a mature silage (11-months-old) were studied. A multimycotoxin method was developed to evaluate the toxigenic in vitro ability of fungal strains. The screening of potentially toxigenic fungi isolated from the mature silage showed that six Fusaria (Fusarium culmorum, Fusarium equiseti, Fusarium graminearum, Fusarium oxysporum,Fusarium solani and Fusarium verticillioides) and one Aspergillus (Aspergillus fumigatus) were able to produce mycotoxins on nutrient agar. Seven major mycotoxins (aflatoxin B₁, citrinin, deoxynivalenol, fumonisin B₁, gliotoxin, ochratoxin A and zearalenone) were also searched in the corn silage by high-performance liquid chromatography coupled to mass spectrometry (HPLC-MS). Among the three mycotoxins (citrinin, gliotoxin and deoxynivalenol) detected in the silage, gliotoxin, a strongly immunosuppressive mycotoxin, occured in the mature silage at level up to 877 ppb, which was associated with the presence of A. fumigatus in the silage.     

Results of a 90-day safety assurance study with rats fed grain from corn borer-protected corn.

The results of a 90-day rat feeding study with grain from MON 810 corn (YieldGard Cornborer -- YieldGard Cornborer is a registered trademark of Monsanto Technology, LLC) that is protected against feeding damage from corn and stalk boring lepidopteran insects are presented. Corn borer protection was accomplished through the introduction of cry1Ab coding sequences into the corn genome for in planta production of a bioactive form of Cry1Ab protein. Grain from MON 810 and its near-isogenic control was separately formulated into rodent diets at levels of 11% and 33% (w/w) by Purina Mills, Inc. (PMI). All diets were nutritionally balanced and conformed to PMI specifications for Certified LabDiet (PMI Certified LabDiet 5002 is a registered trademark of Purina Mills, Inc.) 5002. There were a total of 400 rats in the study divided into 10 groups of 20 rats/sex/group. The responses of rats fed diets containing MON 810 were compared to those of rats fed grain from conventional corn varieties. Overall health, body weight, food consumption, clinical pathology parameters (hematology, blood chemistry, urinalysis), organ weights, and gross and microscopic appearance of tissues were comparable between groups fed diets containing MON 810 and conventional corn varieties. This study complements extensive agronomic, compositional and farm animal feeding studies with MON 810 grain, confirming that it is as safe and nutritious as grain from existing commercial corn varieties.     

Results of a 90-day safety assurance study with rats fed grain from corn rootworm-protected corn.

The results of a 90-day rat feeding study with YieldGard (YieldGard Rootworm Corn is a registered trademark of Monsanto Technology, LLC.) Rootworm corn (MON 863) grain that is protected against feeding damage caused by corn rootworm larvae are presented. Corn rootworm-protection was accomplished through the introduction of a cry3Bb1 coding sequence into the corn genome for in planta production of a modified Cry3Bb1 protein from Bacillus thuringiensis. Grain from MON 863 and its near isogenic control were separately formulated into rodent diets at levels of 11% and 33% (w/w) by Purina Mills, Inc. Additionally, six groups of rats were fed diets containing grain from different conventional (non-biotechnology-derived) reference varieties. The responses of rats fed diets containing MON 863 were compared to those of rats fed grain from conventional corn varieties. All diets were nutritionally balanced and conformed to Purina Mills, Inc. specifications for Certified LabDiet 5002. There were a total of 400 rats in the study divided into 10 groups of 20 rats/sex/group. Overall health, body weight gain, food consumption, clinical pathology parameters (hematology, blood chemistry, urinalysis), organ weights, gross and microscopic appearance of tissues were comparable between groups fed diets containing MON 863 and conventional corn varieties. This study complements extensive agronomic, compositional and farm animal feeding studies with MON 863 grain, confirming that it is as safe and nutritious as existing conventional corn varieties.     

玉米须对糖尿病作用的研究进展

本文总结了近年来玉米须对糖尿病作用的研究进展。实验研究及临床治疗显示,含玉米须复方中成药、玉米须提取物、玉米须多糖、玉米须黄酮、玉米须皂苷有明显的降低血糖的作用。玉米须还具有调节免疫、抗氧化及降脂降压的作用,因而对糖尿病的治疗有辅助作用。而且玉米须在我国资源丰富,因此用其治疗糖尿病的前景十分广阔。     

Results of a 13-week safety assurance study with rats fed grain from corn rootworm-protected, glyphosate-tolerant MON 88017 corn

Presented are the results of a 13-week rat feeding study with grain from MON 88017 corn (brand name YieldGard VT Rootworm/RR2), protected from feeding damage caused by corn rootworm and tolerant to glyphosate, the active ingredient in Roundup agricultural herbicides. Corn rootworm protection is accomplished through the introduction of cryBb1 coding sequence from Bacillus thuringiensis into the corn genome for in planta production of a bioactive form of Cry3Bb1 protein. Also included in the genome is the coding sequence for the CP4 EPSPS protein from Agrobacterium sp. strain CP4 that confers glyphosate herbicidal tolerance. MON 88017 was formulated into rodent diets at 11 or 33% (w/w) levels with its near isogenic control at a level of 33% (w/w). Additionally, six diets containing grain from different conventional (non-biotechnology-derived), reference hybrids were formulated, each at 33% (w/w) levels of one of six reference grains. All diets were nutritionally balanced and conformed to PMI specifications for Certified LabDiet 5002 (PMI Certified LabDiet 5002 is a registered trademark of Purina Mills, Inc.). The responses of rats fed diets containing MON 88017 were comparable to those of rats fed a diet containing grain from its near isogenic control. This study complements extensive agronomic, compositional, and farm animal feeding studies with MON 88017 grain, confirming that it is as safe and nutritious as grain from existing commercial corn hybrids.