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M. D. Harrison Gestur Johnson R. D. Barmington 《American Journal of Potato Research》1970,47(10):386-393
A broadcast application of PCNB (Terraclor) resulted in a reasonably uniform distribution of the chemical in the soil with the concentration decreasing in a linear fashion with increasing depth in the soil profile. A banded application resuluted in a considerably higher chemical concentration at the 4–6 inch depth than at the 0–2 or the 2–4 inch depths. The problem of the lack of uniformity of chemical distribution could probably be solved by altering nozzle placement and size and allow use of the band method of application to minimize grower cost. More complete disking in the case of the broadcast treatment would probably result in a relatively uniform distribution of the chemical but at higher cost to the grower. PCNB application rates of 10, 15 and 25 lbs per acre broadcast and 71/2, 10 and 121/2 lbs per acre in a band significantly reduced the severity ofRhizoctonia infection of Russet Burbank potatoes but did not increase potato yields significantly. 相似文献
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Miranzadeh MB Heidari M Mesdaghinia AR Younesian M 《Pakistan journal of biological sciences: PJBS》2011,14(1):59-63
The objective of the study is surveying microbial quality of drinking water in Kashan rural areas and determining the rural population that using safe water in terms of microbial quality in second-half of 2008. In this cross-sectional study, microbial quality of water in all rural areas was determined in 3 stages based on 3 parameters as Total Coliforms, Fecal Coliforms and Heterotrophic Plate Count (HPC). The results of this study illustrates that 100.0, 47.71 and 92.99% population in under coverage and non under coverage areas of Kashan Rural Water and Wastewater Company (KRWWC) and all Kashan rural areas, respectively using safe water in terms of Fecal Coliforms and 98.4, 21.2 and 88.00% population in under coverage and non under coverage areas of KRWWC rural areas and all Kashan rural areas, respectively using safe water in terms of Total Coliforms. There is also a meaningful difference in microbial quality between under coverage and non-under coverage rural areas. The results of this study express that the fecal contamination in under coverage rural areas is excellent, but there is a bad condition in non-under coverage areas. Generally, the microbial quality in all Kashan rural areas is approximately equal to national microbial criteria. Its been also illustrated that the role of KRWWC in supplying safe drinking water in terms of microbial quality for rural population is very important. 相似文献
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A three-year study in central Wisconsin with timed foliar applications of maleic hydrazide at 3 lb/A (3.36 kg/ha) resulted in an improvement in quality and a favorable alteration in the shape of tubers of the Russet Burbank potato variety. Application in early and mid-July resulted in an increase in yield of U.S. 1 tubers and reduced yield of malformed tubers. Over 40 percent fewer misshapen tubers were produced when applications of maleic hydrazide were made during July when compared with tubers from untreated plants. Applications made in midor late July resulted in tuber development with a more favorable length to diameter ratio of U. S. 1 tubers, again compared with tubers from untreated plants. Maleic hydrazide applied in early or mid-June resulted in severely reduced yield and increased incidence of misshapen tubers. When applied in July or early August, no effect on tuber specific gravity was found. Maleic hydrazide functioned as an effective sprout inhibitor on tubers from all treatment dates except when applied in early June. 相似文献
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Watermelon yield loss due to Fusarium wilt is increasing in the U.S., due in part to the emergence of the virulent race 2 of Fusarium oxysporum f. sp. niveum, and to the shift in production to triploid cultivars, which generally have less host resistance than previously grown diploid cultivars. One potential management strategy is the use of soil-applied fungicides to reduce Fusarium wilt. The U.S. national program, interregional project 4 (IR-4) supported multistate trials of soil-applied chemicals to manage Fusarium wilt of watermelon. Greenhouse trials were conducted in Maryland, Indiana and Georgia to test the efficacy of 14 chemicals on Fusarium wilt. Based on the performance of these chemicals in the greenhouse, six in Maryland and Delaware and eight in Indiana were selected for subsequent field evaluations. These chemicals were applied once, as a drench at planting, in field trials in Maryland, Indiana, and Delaware in 2008. The fungicides prothioconazole, acibenzolar-S-methyl, and thiophanate-methyl resulted in the greatest reduction in Fusarium wilt, and caused no phytotoxicity. In Maryland and Indiana in 2009, these chemicals were applied through the drip irrigation line alone and in combination, at 0, 2 and 4 weeks after planting. The experiment was repeated in 2010 in Maryland. Prothioconazole alone and in combination with acibenzolar-S-methyl or/and thiophanate-methyl resulted in the greatest decrease in the area under the disease progress curve (AUDPC) of Fusarium wilt of watermelon in Maryland in 2009. The same trend was observed in 2010 in Maryland where three of the prothioconazole treatments ranked the lowest of all treatments and prothioconazole in combination with thiophanate-methyl had significantly lower Fusarium wilt AUDPC compared to the non-treated control. All chemical applications except for acibenzolar-S-methyl in combination with prothioconazole reduced Fusarium wilt AUDPC in Indiana in 2009. Prothioconazole alone and prothioconazole in combination with thiophanate-methyl ranked lowest in Fusarium wilt AUDPC, although not significantly lower than most other treatments. These studies are the first to demonstrate that the soil-applied fungicides prothioconazole and thiophanate-methyl may provide an additional field management option for Fusarium wilt of watermelon. 相似文献
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东北三省玉米气候适宜度变化分析 总被引：6，自引：1，他引：5
利用东北三省25个农业气象观测站平均资料及176个气象站1961～2007年的逐日气象资料,对玉米全生育期及各主要玉米生育阶段的气候因子及综合气候适宜度进行计算分析。结果表明,自1961年以来,玉米各发育期对气候因子适宜程度不同,播种期-出苗期、出苗期-开花期、开花期-成熟期温度适宜度呈上升趋势,日照适宜度呈下降趋势;播种期-出苗期降水呈上升趋势,其余各生育期降水均为下降趋势。玉米全生育期降水、日照适宜度呈下降趋势,温度适宜度呈上升趋势,综合气候适宜度东北三省均呈下降趋势。各气候因子组合效果较好,玉米产量与各生育阶段的不同气候因子的适宜度相关性差异较大。 相似文献
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木薯蔗糖转运蛋白基因的表达分析 总被引：1，自引：0，他引：1
以木薯SC124为材料,分别在植株发育8个时间点取其块根和功能叶,利用实时定量PCR技术（qPCR）对木薯SUT1、SUT2、SUT4三类蔗糖转运蛋白基因表达差异进行研究。结果表明,在木薯块根形成期（90 d）3类SUT表达的日变化中,功能叶和块根中均以中午12 h最高,其余时间较低,叶片中SUT1和SUT2表达水平较高而块根中差异不显著;在整个发育过程中,叶片表达水平高于块根,且二者均为前期表达水平高,后期下降,3个SUT之间的表达量也有着明显的差异,叶片中SUT1的表达量最高,其次是SUT2,SUT4最低,在块根中除60 d时SUT1的表达量较高外,其它SUT表达量均较低,SUT4在叶片和块根中的表达量差异不大。 相似文献
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波罗蜜叶片突变体叶绿素含量测定和超微结构观察 总被引：1，自引：0，他引：1
波罗蜜（Artocarpus heterophyllus）是一种热带果树,至今对其突变体的研究少有报道。本研究以波罗蜜叶片为试验材料,探究其叶片出现白化和返绿现象的可能原因。（1）用分光光度计法、比色法测定波罗蜜叶片突变体和正常绿叶的叶绿素及叶绿素前体物质含量;（2）用叶绿素酶Elisa试剂盒测定叶绿素酶活性;（3）用透射电子显微镜对叶绿体的超微形态结构进行观察。研究结果表明：（1）不同叶色所产生的叶绿素a含量、叶绿素b含量、叶绿素总含量、类胡萝卜素含量均存在显著差异;（2）波罗蜜叶片突变体和正常绿叶的叶绿素合成前体物质含量之间并没有出现显著性差异;（3）对波罗蜜叶片的叶绿素酶活性进行测定时,发现其活性出现显著差异,但对其叶绿素含量的差异性并没有产生较大影响;（4）观察波罗蜜叶片内叶绿体超微形态结构时,发现正常绿叶的叶绿体形态完好且数量较多,白化叶和返绿叶的叶绿体内部结构存在缺陷,其原因是叶绿体基粒构建阶段受阻;基于测定波罗蜜叶片中的叶绿素、叶绿素前体物质含量和叶绿素酶活性,并观察波罗蜜叶片内叶绿体的超微形态结构,对得到的数据结果进行比较分析。本研究推测是在叶绿素合成阶段,原脱植基叶绿素合成叶绿素时受阻及叶绿体发不良导致波罗蜜出现白化和返绿现象,为今后进一步综合研究波罗蜜突变体提供理论依据。 相似文献
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2020年10月17日,《中华人民共和国生物安全法》(以下简称《生物安全法》)通过全国人大常委会的审议,自2021年4月15日起施行.生物技术的研究与应用安全是《生物安全法》涉及的主要内容之一,基因编辑作为近几年生物技术领域的研究热点,其安全性评价和监管备受关注.本文概述了基因编辑技术的应用现状,比较了不同国家对基因编... 相似文献
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为寻求不同播种方式对大穗型和多穗型两类品种分蘖成穗的影响及高产栽培的群体调控技术指标,以山东省具有代表性的四个小麦品种为材料,研究了在稀植点播条件下的分蘖与成穗潜力及播种方式对产量的影响.结果表明,两类参试品种在稀植条件下均具有较高的单株分蘖力、成穗数及成穗率,但品种间存在较大差异.两类品种分蘖与成穗特点受群体环境的影响程度均较大,其中,两个大穗型品种山农8355和山农01-35又影响的程度更高,而两个多穗型品种济麦20和鲁麦14分蘖成穗特点对群体环境的响应程度不如大穗型敏感.播种方式对产量的影响程度因品种而异,多穗型品种单产均表现为宽行＞窄行＞撒播,但只有撒播与宽行和窄行间差异显著;大穗型品种均以窄行的产量最高,高低依次为窄行＞宽行＞撒播,但只有山农01-35品种达到显著差异水平.撒播减产的原因主要是前期过高的分蘖力导致群体数量增加,降低了个体干物质积累,穗粒数及粒重大幅度下降. 相似文献
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以6个不同花色的小苍兰品种为实验材料,在量化小苍兰花色表型和初步确定花瓣色素类型的基础上,利用UPLC-Q-TOF-MS技术鉴定花瓣中的花黄色素组成并比较分析各组分含量。结果表明：在小苍兰花瓣中鉴定到13种黄酮及黄酮醇物质,分别为槲皮素、山萘酚、异鼠李素、柚皮素、黄芩素及其糖苷;槲皮素及其糖苷是小苍兰花瓣中重要的黄酮醇物质;随着小苍兰的花朵开放,花黄色素含量多呈下降趋势;在不同小苍兰品种中,花黄色素含量存在明显差异,其中,红、紫色系品种含量显著高于黄、白色系品种,尤其是‘上农红台阁’‘Red Passion’和‘Castor’,其含量在各发育阶段均表现为较高水平的积累。此外,花色表型为复色的‘Red Passion’和‘Castor’中上部与基部花瓣的花黄色素含量存在显著差异。相关分析表明,各花黄色素组分的积累与小苍兰花色明度均呈极显著负相关;槲皮素、异鼠李素及其糖苷含量与花色红度呈极显著正相关,柚皮素、山萘酚及其糖苷与花色红度呈显著正相关;山萘酚及其糖苷含量与花色鲜艳程度呈显著正相关。可见,花黄色素影响小苍兰的花色呈现。 相似文献
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土壤质地对小麦旗叶部分生理活性的影响 总被引：2，自引：0，他引：2
为了给小麦高产优质栽培和生态区划提供依据,在黏、壤、砂三种土壤质地池栽条件下对豫麦49旗叶硝酸还原酶活性、全氮含量、可溶性蛋白含量、可溶性糖含量的变化进行了研究.结果表明,旗叶硝酸还原酶活性在开花15 d之后砂土地均低于其他两种土壤质地,黏土条件下种植的较高;旗叶可溶性糖含量表现为砂土>黏土>壤土;旗叶可溶性蛋白含量开花15 d之后及整个灌浆期间旗叶全氮含量均表现为黏土>壤土>砂土;花后35 d至成熟粒重表现为壤土>砂土>黏土,成熟时粒重为壤土46.10 mg,砂土43.59 mg,黏土41.05 mg. 相似文献
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2006-2014年,应用病土盆栽方法,对来自于12个省(市)的779份大豆种质资源进行了大豆胞囊线虫3号生理小种的抗病性鉴定。鉴定材料来源于吉林省539份、黑龙江省58份、辽宁省51份、山西省16份、内蒙古17份、河北省10份、北京市42份、安徽省5份、广西壮族自治区14份、河南省17份、山东省6份、江苏省4份。从中选出19份抗病种质,占鉴定总数的2.44%,分别是FY001-3、W93155、JH229、HJ01-1900、W94128-8、YX04-6561、W7491、W201102-25、Q30、Q31、HK6、HK7、BN9、CM2008-12、JY407、Q32、Q28、Q33、BN10,按抗病种质在各省份鉴定材料中所占的比例来看,山东省大豆种质抗病比例最高,占83.33%,其次是黑龙江省占15%。这些品种(系)的农艺性状优良,可直接作为抗性亲本应用于育种。 相似文献
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Insect pest management is facing the economic and ecological challenge worldwide due to the human and environmental hazards caused by majority of the synthetic pesticide chemicals. Identification of novel effective insecticidal compounds is essential to combat increasing resistance rates. Botanicals containing active insecticidal phytochemicals appear to be promising to address some of these problems. Therefore, there is a continuous need to explore new active molecules with different mechanisms of action. Secondary metabolites present in plants apparently function as defense (toxic), which inhibits reproduction and other processes. The phytochemical biomolecules could be used for maximizing the effectiveness and specificity in future insecticide design with specific or multiple target sites, while ensuring the economic and ecological sustainability. In this article, the current state of knowledge on phytochemical sources and insecticidal activity, their mechanism of action in insects, resistance, and promising advances made in phytochemical research are reviewed. 相似文献
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为了探明不同类型大麦品种籽粒中酚酸类化合物含量的差异,采用超声辅助提取、高效液相色谱测定的方法对15个大麦品种（系）籽粒中的13种酚酸含量进行了比较分析。结果表明,大麦籽粒中的酚酸类化合物主要是羟基苯甲酸衍生物,羟基肉桂酸衍生物含量较少。不同类型大麦品种籽粒中酚酸类化合物的含量存在极显著的差异,黑皮大麦籽粒中总羟基苯甲酸衍生物（THBA）、总羟基肉桂酸衍生物（THCA）和总酚酸（TPA）的含量均高于非黑皮大麦;二棱大麦籽粒中THBA、THCA和TPA的含量均高于多棱大麦;皮大麦籽粒中THCA和TPA的含量高于裸大麦,但THBA的含量与裸大麦无显著差异。另外,与裸大麦相比,皮大麦籽粒中含有更为丰富的酚酸种类。 相似文献
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2007年粳稻市场分析及2008年走势展望 总被引：1，自引：0，他引：1
以翔实的资料对2007年我国粳稻米产量、消费量、进出口数量、供求平衡结果、库存变化、价格走势以及国际粳稻米供求情况进行了全面地分析,并在此基础上对影响2008年粳稻米市场价格的各种因素进行了深入研究,由此预测出2008年我国粳稻米市场的价格变化趋势:价格整体上将呈稳中有升态势,但增幅不会太大。 相似文献
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为了寻找一种高效的荔枝果实瞬时基因表达方法,本研究以荔枝品种‘新球蜜荔’（Litchi chinensis Sonn. var. ‘Xinqiumili’）为试材,利用农杆菌注射法对荔枝果实组织进行转化,研究了果实发育时期、菌株种类、注射部位、取样时间、菌液浓度等对转化效率的影响。结果表明：选择果肉已完全包裹种子的Ⅱb期果实进行连体注射,在果柄、果皮、种子、果肉分别注入OD600值为2.4的农杆菌菌株GV3101,4 d后取样进行检测,4个组织的GUS染色率较高。本研究成功建立了适用于荔枝果实的基因瞬时表达系统,为今后快速鉴定荔枝果实相关基因功能提供了基础。 相似文献