柑桔大食蝇防治     

杜德平 《北京农业》2011,(33):77

柑桔大食蝇疫情呈逐年加重趋势,由于其发生面积大,危害损失重,疫区果实不准外销,给果农造成了巨大的经济损失,已成为柑桔生产上的第一大虫害。  相似文献   

An effective biophysical indicator for opium yield estimation     

Kun Jia  Bingfang Wu  Yichen TianQiangzi Li  Xin Du 《Computers and Electronics in Agriculture》2011,75(2):272-277

Opium is a narcotic obtained from opium poppy and raw materials of heroin for illegal drug trade. Information on opium production is important for governments and international communities to understand the scale of illegal drug trade and to implement drug fighting policies. Opium production can be estimated from opium yield and poppy cultivation acreage. Poppy cultivation acreage in turn can be estimated using remote sensing technique. This study explores the feasibility of assessing opium yield using remote sensing technique. The objective of this study is to find an effective biophysical indicator that can be related to both opium yield estimation and remote sensing measurements. Data are obtained from three years ground experiments conducted in an official farm in North-Western China. Opium yield and main plant and environmental parameters of opium poppy are measured. A linear regression analysis measures the relationship between opium yield and main plant parameters. A strong correlation between opium yield and leaf area index (LAI) in flowering and harvesting periods of opium poppy is observed (R² = 0.826 and 0.862 respectively). LAI is a good indicator during flowering and harvesting periods and can be used to build a model for opium yield estimation. Furthermore, LAI can be retrieved using remote sensing at a region scale. The study shows that remote sensing could be used to estimate opium yield in opium poppy concentrated regions, and that a more comprehensive and precise opium production information could be obtained for further analysis of illegal drug circulating trend and policy.  相似文献   

沙棘多糖抗氧化活性的研究   总被引：2，自引：0，他引：2  

杜晶晶  杨宏志 《黑龙江八一农垦大学学报》2011,23(2):49-52

从还原力、清除超氧阴离子自由基、清除羟自由基、清除DPPH自由基4个方面研究了沙棘多糖的体外抗氧化活性,并同vc进行比较.结果表明,沙棘多糖对O2-·清除能力明显强于Vc,EC50为0.2mg·mL-1;还原力较低;抑制羟自由基产生能力略低Vc,EC50为0.597 mg·mL-1;清除DPPH·的能力略低于Vc,清除...  相似文献   

加拿大农业系统前沿研究现状及其对中国的管理启示     

杜宇能  方冰 《世界农业》2011,(1)

介绍了加拿大农业系统前沿研究的内容、方法和发展趋势,综述了加拿大农业系统研究中使用的主要方法,概述了基于GIS的土地资源优化模型(LUAM)的特点和流程.并结合加拿大和中国农业系统研究的比较分析,提出了针对中国的农业系统研究的管理启示.  相似文献   

长春市木本植物春季物候对气候变化的响应   总被引：5，自引：3，他引：2  

神祥金吴正方  刘彩伶杜海波李明  宗盛伟 《中国农学通报》2012,28(1):112-117

根据中国物候观测网络长春观测站点的物候资料及国家气象中心提供的气象资料,采用相关分析、多元回归分析和数学模拟方法,分析了2003-2010年长春市木本植物春季物候与温度、日照、降水之间的相关关系,建立了模拟和预报4种木本植物开花始期的模型。结果表明：在各种气候因子中,温度对春季物候影响最大,日照、降水影响不显著;温度对春季物候影响集中在物候期前2个月,温度升高,春季物候期提前。春季物候期持续日数与1、2月份温度有关,分别与芽萌动期和展叶期成正相关和负相关。开花始期回归模型预测值与物候观测数值拟合较好,表明可以使用回归模型对长春几种木本开花期进行预测。  相似文献   

水稻抗性淀粉含量性状的配合力分析     

孙春龙白建江  施标朱辉明  朴钟泽都兴林 《中国农学通报》2012,28(12):24-28

抗性淀粉对人体具有多种重要的生理功能,为了获得具有高抗性淀粉含量的水稻杂交后代,选用6个抗性淀粉含量具有显著差异的水稻品种按Griffing双列杂交设计配置成杂交组合,及正反交F1为材料研究了水稻籽粒抗性淀粉含量性状的遗传规律。结果表明,水稻抗性淀粉含量在参试组合中加性效应起主要的作用,同时受非加性效应以及细胞质效应的影响。一般配合力(GCA)效应在各亲本间存在明显差异,‘降糖稻1号’和‘丙9331’亲本均表现很高的正向一般配合力(GCA)效应值,其一般配合力效应值分别为0.303和0.101。其他品种均表现负向一般配合力(GCA)效应值。亲本本身的抗性淀粉含量与一般配合力的表现趋势一致,与相应的特殊配合力(SCA)有明显的相关性,与杂种一代表现有显著的相关性,表明利用亲本表型值对于预测组合的杂种优势具有一定的意义。  相似文献   

新疆农八师垦区气候变化及对农业的影响   总被引：5，自引：3，他引：2  

杜红 杜峰李红英  范金霞王进 《中国农学通报》2012,28(20):290-294

摘要：为了新疆农八师垦区农业生产的可持续发展和防灾减灾提供参考,使用该地区气象资料,应用气候倾向率、气候趋势系数等统计方法分析气候变化的同时探讨气候变暖对农业生产的影响。结果表明：气温升高趋势明显,年平均气温倾向率为0.349 ℃/10a,其中冬半年倾向率为0.446 ℃/10a,夏半年倾向率为0.293 ℃/10a;降水量存在增加趋势,年降水量倾向率为15.227 mm/10a,其中作物生长季平均降水量倾向率为9.186 mm/10a,冬季降水量倾向率为4.716 mm/10a;日照时数有微弱增加趋势,年日照总量倾向率为24.861 h/10a,作物生长季日照时数倾向率为24.035 h/10a;春季倾向率为18.141 h/10a。气候变暖增加了该地区热量资源使棉花栽培界限西进北移扩大了种植面积,同时极端气候事件的不稳定性及病虫害加重现状增加了农业对防灾的投入,所以掌握气候变化规律,适应气候变化调整农业生产,因势利导趋利避害是丰产丰收的保障。  相似文献   

BMY牛不同生长阶段血液理化指标的检测   总被引：1，自引：1，他引：0  

张继才和占星  杨世平金显栋  付美芬杨凯王安奎  黄必志 《中国农学通报》2012,28(29):66-70

为了解BMY牛血液理化指标随年龄的变化规律。用自动分析仪法对30头不同年龄阶段的BMY的39项血液理化指标进行了检测。结果表明：WBC、RBC、P和ALP等部分指标随年龄增长而降低;PLT、TB、Crea、LDH和ALT等指标随年龄增长而升高;URIC、Ca、AMY和AST等指标在不同年龄段变化不明显。各项指标的测定结果均未超出正常范围。  相似文献   

大棚设施栽培对管花肉苁蓉接种及生长的影响   总被引：1，自引：1，他引：0  

王宏国 杜友崔旭盛  郭玉海 《中国农学通报》2012,28(34):279-283

接种肉苁蓉个数、分枝个数、分枝长度、鲜重、干重。大棚设施栽培能显著提高管花肉苁蓉接种率(66.67%),单株柽柳接种管花肉苁蓉的个数提高116.67%;柽柳的分枝数、分枝总长度及分枝平均长度依次增加28.02%、71.31%、28.73%;柽柳根、茎、光合枝及管花肉苁蓉鲜重依次增加62.27%、121.47%、93.89%、131.09%;柽柳根、茎、光合枝及管花肉苁蓉干重依次增加23.75%、116.16%、35.18%、72.70%;大棚设施栽培管花肉苁蓉鲜干比为4.40,大田露地栽培管花肉苁蓉鲜干比为3.11大棚设施栽培管花肉苁蓉可溶性糖含量降低了16.77%,SSC含量降低了13.71%;但两者的累积量均高于大田栽培,其中可溶性糖累积量增加92.42%,SSC累积量增加99.40%。大棚设施栽培能够促进柽柳和管花肉苁蓉的生长,较大田更适宜管花肉苁蓉的生产。  相似文献   

An antibiotic complex from Lysobacter enzymogenes strain C3: antimicrobial activity and role in plant disease control     

Li S  Jochum CC  Yu F  Zaleta-Rivera K  Du L  Harris SD  Yuen GY 《Phytopathology》2008,98(6):695-701

Lysobacter enzymogenes C3 is a bacterial biological control agent that exhibits antagonism against multiple fungal pathogens. Its antifungal activity was attributed in part to lytic enzymes. In this study, a heat-stable antifungal factor (HSAF), an antibiotic complex consisting of dihydromaltophilin and structurally related macrocyclic lactams, was found to be responsible for antagonism by C3 against fungi and oomycetes in culture. HSAF in purified form exhibited inhibitory activity against a wide range of fungal and oomycetes species in vitro, inhibiting spore germination, and disrupting hyphal polarity in sensitive fungi. When applied to tall fescue leaves as a partially-purified extract, HSAF at 25 mug/ml and higher inhibited germination of conidia of Bipolaris sorokiniana compared with the control. Although application of HSAF at 12.5 mug/ml did not reduce the incidence of conidial germination, it inhibited appressorium formation and suppressed Bipolaris leaf spot development. Two mutant strains of C3 (K19 and DeltaNRPS) that were disrupted in different domains in the hybrid polyketide synthase-nonribosomal peptide synthetase gene for HSAF biosynthesis and had lost the ability to produce HSAF were compared with the wild-type strain for biological control efficacy against Bipolaris leaf spot on tall fescue and Fusarium head blight, caused by Fusarium graminearum, on wheat. Both mutant strains exhibited decreased capacity to reduce the incidence and severity of Bipolaris leaf spot compared with C3. In contrast, the mutant strains were as efficacious as the wild-type strain in reducing the severity of Fusarium head blight. Thus, HSAF appears to be a mechanism for biological control by strain C3 against some, but not all, plant pathogenic fungi.  相似文献