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长期定位施肥对砂姜黑土肥力及生产力的影响研究 总被引：7，自引：1，他引：7
长期定位试验研究化肥与有机肥配施对砂姜黑土土壤肥力和作物产量的影响结果表明 ,长期施肥可提高土壤碱解氮、速效磷及有机质含量 ,不同肥料组合间差异较大 ,以有机肥与化肥配施处理效果最佳 (但同时必须重视K素的投入 ) ,土壤速效钾仅全部施用有机肥处理有所增加 ,单施N、P化肥处理下降最多 ,至 15年后下降2 5 .8%。长期未施肥处理 (对照 )碱解氮变化最大 ,较试验前下降 2 6 .5 % ,其他养分指标变化较小。有机肥与化肥配施处理产量前期不及单施化肥处理 ,中后期则反之。砂姜黑土基本生产力随种植时间延长而渐降 ,土壤对秋粮大豆或玉米的供肥能力高于小麦。 相似文献
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Dong Wen-Long Liu Lei Odah Kokou Ayefounin Atiah Luke Atiewin Gao Yun-Hang Kong Ling-Cong Ma Hong-Xia 《Tropical animal health and production》2019,51(7):2099-2103
Tropical Animal Health and Production - Trueperella pyogenes (T. pyogenes) is a worldwide known pathogen of domestic ruminants and pigs causing a wide variety of infections. The objective of this... 相似文献
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Kong Ling-Cong Wang Zi Wang Yi-Ming Dong Wen-Long Jia Bo-Yan Gao Duo Jiang Xiu-Yun Ma Hong-Xia 《Tropical animal health and production》2019,51(4):987-992
Tropical Animal Health and Production - Pasteurella multocida (P. multocida) is an important pathogen that causes bovine respiratory disease (BRD) in China and other countries. To investigate the... 相似文献
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Ling-Cong KONG Duo GAO Bo-Yan JIA Zi WANG Yun-Hang GAO Zhi-Hua PEI Shu-Ming LIU Jiu-Qing XIN Hong-Xia MA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):293-296
Mycoplasma bovis has spread widely throughout the world via animal movement and has become
an important pathogen of bovine respiratory disease. However, the minimum inhibitory concentrations of
antimicrobials for Mycoplasma bovis have not been studied in China. The objective of this
study was to determine the prevalence and antibiotic resistance of Mycoplasma bovis isolated
from young cattle with respiratory infection in China. Mycoplasma bovis was detected in 32/45
bovine respiratory infection outbreaks at beef farms in 8 provinces in China. The isolates were susceptible or
had medium sensitivity to ciprofloxacin, enrofloxacin and doxycycline, but were frequently resistant to
macrolides (13/32, 41%). An A2058G (Escherichia coli Numbering) mutation located in the
rrnA operon in domain V of 23S rRNA was observed in strains that were resistant to
macrolides. This single mutations at the rrnA operon in domain V of 23S rRNA may play an important role in the
resistance of Mycoplasma bovis strains to macrolides. 相似文献
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Ling-Cong KONG Duo GAO Yun-Hang GAO Shu-Ming LIU Hong-Xia MA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2014,76(12):1655-1657
The minimum inhibitory
concentrations (MICs), mutation prevention concentrations (MPCs) and contribution of
quinolone resistance-determining region (QRDR) mutations to fluoroquinolone
(ciprofloxacin, enrofloxacin and orbifloxacin) susceptibility in 23 Pasteurella
multocida (Pm) isolates were investigated.
Fluoroquinolone-susceptible isolates (MICs ≤0.25 µg/ml,
9 isolates) had no QRDR mutations, and their respective MPCs were low.
Fluoroquinolone-intermediate isolates (MICs=0.5 µg/ml,
14 isolates) had QRDR mutations (Asp87 to Asn or Ala84 to Pro in gyrA),
and their respective MPCs were high (4–32 µg/ml).
First-step mutants (n=5) and laboratory-derived highly resistant fluoroquinolone mutants
(n=5) also had QRDR mutations. The MICs of fluoroquinolones for mutant-derived strains
were decreased in the presence of efflux inhibitors. The results indicated that the
fluoroquinolone resistance of Pm is mainly due to multiple target gene
mutations in gyrA and parC and the overexpression of
efflux pump genes. 相似文献
6.
砂姜黑土长期施肥对小麦生长的影响研究 总被引：4，自引：2，他引：4
砂姜黑土20年长期定位施肥试验研究结果表明,不同施肥处理对小麦产量的影响明显,各处理产量为Ⅳ>Ⅲ>Ⅱ>Ⅰ>CK,单施化肥有利于培育大蘖壮苗,利用增穗增粒对提高产量有一定作用,但因提高土壤肥力作用较小而难以高产。单施有机肥培肥作用明显,但其养分释放缓慢,影响小麦对养分的吸收,且生育前期营养生长不良,群体不足,小麦增产幅度较小。有机肥与化肥配施养分供应平衡,群体动态、产量结构合理,是砂姜黑土地区小麦持续高产和土壤培肥的有效措施,但应同时重视K肥施用。 相似文献
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江淮地区是我国水稻和小麦重要的生产基地,明确该地区不同产量水平之间的差异特征及形成机制,探索区域粮食生产的限制因子,可为缩减江淮地区周年产量差的技术途径提供科学依据和参考。本研究以稻–麦周年生产体系为研究对象,定量分析不同产量水平田块之间的产量差与气候影响因素。结果表明,江淮地区水稻、小麦及周年农户水平与试验水平和高产纪录间存在显著的产量差,分别为3315.9、1537.5、4645.6 kg hm–2和7498.6、3977.9、9840.9 kg hm^–2。水稻、小麦及周年农户水平较试验水平还有46.2%、29.7%和37.3%的增产潜力,较高产纪录还有104.5%、77.0%和79.0%的增产潜力。每穗粒数是造成水稻产量差的主要因子,穗数和每穗粒数是造成小麦产量差的主要因子。与农户水平相比,水稻试验水平和高产纪录的穗粒数分别增加30.4%和116.1%;小麦试验水平和高产纪录的穗数和每穗粒数平均分别增加40.9%、70.0%和21.8%、19.6%。缩小产量差水稻主要依赖于增加每穗粒数,小麦靠穗数和每穗粒数的协同提高。生育期累积辐射和积温较低是导致水稻产量差异的主要气候因素,而生育期降雨过多是导致小麦产量差异的主要气候因素。根据研究提出了“强稻稳麦”是提升江淮地区周年粮食生产的有效途径。 相似文献
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施肥对砂姜黑土基础肥力及强筋小麦产量、品质的影响 总被引：7，自引：0，他引：7
为探讨不同施肥方式对砂姜黑土的培肥效果和不同土壤基础肥力水平对优质强筋小麦产量及品质的影响,在22年长期定位试验的基础上,研究了不同施肥方式下砂姜黑土基础肥力的变化,并分析了土壤主要养分性状与强筋小麦产量和品质的关系.结果表明,长期单施有机肥或有机肥与化肥配合施用均能较单施化肥处理显著提高土壤全氮、有机质、碱解氮、速效磷及速效钾的含量;同一施氮水平,有机肥与化肥配施处理的基础肥力产量(不施肥时的产量)较单施化肥的高2715.0kg·hm-2.土壤有机质、全氮、全磷及速效磷含量与籽粒产量、蛋白质、湿面筋和沉降值均呈正相关.有机肥与化肥配施不仅是培肥地力的主要途径,同时还是确保优质小麦保优栽培,实现可持续发展的有效措施. 相似文献
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DU Xiang-Bei XI Min KONG Ling-Cong WU Wen-Ge CHEN Jin-Hua XU You-Zun ZHOU Yong-Jin 《作物学报》1962,47(2):351-358
The Yangtze-Huaihe rivers region is an important production base of rice and wheat in China. It is necessary to clarify the differences and formation mechanism between different yield levels in the region, and to explore the limiting factors for regional grain production, which can provide scientific basis and reference for the management practices to reduce the annual yield gap in the Yangtze-Huaihe rivers region. Based on annual rice-wheat production situation, crop yield was divided into three different levels, farmer yields, experimental yields and high record yields. Yield gaps and the climate factors of different yield levels were quantified. Results showed that there were significant differences between farmer yields and experimental yields, high record yields of rice, wheat and annual in the Yangtze-Huaihe rivers region, which were 3315.9, 1537.5, and 4645.6 kg hm-2, 7498.6, 3977.9, and 9840.9 kg hm-2, respectively. Compared with the experimental yields, the farmer yields of rice, wheat and annual had yield increase potential of 46.2%, 29.7% and 37.3%, and 104.5%, 77.0% and 79.0% in comparison with the high record yields, respectively. The number of grains per spike was the main factor resulting in the yield difference in rice, and the grain numbers per spike and the number of spikes contributed to the yield difference in wheat. Compared with the farmer average yield, the grain numbers per spike of rice in experimental yields and high record yields were increased by 30.4% and 116.1%, respectively; the spikes and grain numbers per spike of wheat were increased by 40.9%, 70.0% and 21.8%, 19.6%, respectively. Reducing the yield gaps mainly depended on increasing the grain numbers per spike for rice, and synergistic improvement in the number of spikes and the grain numbers per spike for wheat. Cumulative radiation and low accumulated temperature during the growth period were the main climatic factors affected rice production, while excessive rainfall was the main climatic factor affected wheat production. The results suggested that in order to strengthen rice production and stabilize wheat production was an effective way to increase the annual grain production in the Yangtze-Huaihe rivers region. 相似文献
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