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131.
132.
推广使用高效、安全的麦田除草剂是控制节节麦等麦田恶性杂草严重发生的经济有效的措施之一,本试验采用田间试验方法研究了AEF1300603OF(3%世玛油剂)及WG13A13.6WG对麦田恶性杂革的防治效果。试验结果表明,WG13A13.6WG对麦田杂草防除效果显著,其最佳用量为25~35g/667m^2。在小麦返青期,对节节麦防效达85%~95%,对蜡烛草的防效达85%~90%,对播娘蒿、荠菜的防效达100%,对猪殃殃、婆婆纳等抗性较强的杂革防效也在90%~100%,均高于AEF1300603OF的防除效果。收获首田间调查发现防效趋势与首期调查结果一致。而且WG13A13.6WG防除杂草后使小麦的增产幅度在16.27%~25.48%。 相似文献
133.
Keke Hua Zhibin Guo 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2018,68(6):505-514
Current understanding of the effects of long-term application of various organic amendments on soil particulate organic matter (POM) storage and chemical stabilisation remains limited. Therefore, we collected soil samples from the soil profile (0–100?cm) under six treatments in a 31-year long-term fertilisation experiment: no fertiliser (CK), mineral fertilisers (NPK), mineral fertilisers plus 3.8 or 7.5?t?ha?1?year?1 (fresh base) the amount of wheat straw (1/2SNPK and SNPK) and mineral fertilisers plus swine or cattle manure (PMNPK and CMNPK). Long-term incorporation of wheat straw and livestock manure amendments significantly (p?<?0.05) increased crop yield and sustainable yield index, and POM storage compared with CK and NPK treatments. The mole ratios of H/C in the POM under organic amendment treatments significantly (p?<?0.05) decreased by 13.8% and 37.1%, respectively, compared with the NPK treatment. Similarly, solid state NMR spectroscopy showed that the O–alkyl carbon content of POM was greatly decreased, whereas aromatic carbon contents and alkyl to O–alkyl carbon ratios were substantially increased under PMNPK and CMNPK treatments. In conclusion, we recommend long-term livestock manure application as a preferred strategy for enhancing POM quantity and quality (chemical stability), and crop yield of vertisol soil in northern China. 相似文献
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135.
【目的】探索小麦新种质P13对条锈病的抗病性及其抗性机制,为P13种质的进一步推广利用提供理论依据。【方法】以铭贤169为感病对照,用6个条锈菌生理小种(CYR23、CYR29、CYR31、CYR32、CYR33和Hybrid46-8)对P13进行苗期抗条锈性鉴定;采用自然诱发法鉴定P13的田间抗条锈性;以P13和铭贤169为材料,采用常规的夏孢子悬浮液涂抹法接种条锈菌CYR29,以不接种为对照,然后测定多酚氧化酶(PPO)、过氧化物酶(POD)、苯丙氨酸解氨酶(PAL)、β-1,3-葡聚糖酶和几丁质酶等抗病相关酶活性。【结果】苗期P13对CYR32表现为免疫,对CYR29、CYR33和Hybrid46-8表现为近免疫,对CYR23表现为高抗,对CYR31表现为感病。P13在拔节期、孕穗期和乳熟期均表现为免疫或近免疫。 P13接种条锈病菌CYR29后,其叶片内POD、PAL、PPO、β-1,3-葡聚糖酶和几丁质酶的活性均高于未接种植株和感病对照铭贤169。【结论】P13对贵州小麦条锈菌生理小种表现出较强的抗病性,其在贵州小麦生产及抗病育种方面具有极高的应用价值。 相似文献
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137.
Doongar R. Chaudhary Richard P. Dick 《Communications in Soil Science and Plant Analysis》2016,47(9):1193-1206
Photosynthetically derived rhizodeposits are an important source of carbon (C) for microbes in root vicinity and can influence the microbial community dynamics. Pulse labeling of carbon dioxide (13CO2) coupled with stable isotope probing techniques have potential to track recently fixed photosynthate into rhizosphere microbial taxa. Therefore, the present investigation assessed the microbial community change associated with the rhizosphere and bulk soil in Jatropha curcas L. (a biofuel crop) by combining phospholipid fatty acid (13C-PLFA) profiling using a stable isotope 13CO2 labeling approach. The labeling (13C) took place after 45 days of germination, PLFAs were extracted from both soils (rhizosphere and bulk) after 1 and 20 days pulse labeling and analyzed by gas chromatography-isotope ratio mass spectrometry. There was no significant temporal effect on the PLFA profiles in the bulk soil, but significantly increased abundance of Gram positive (i15:0) and Gram negative (16:1ω7c and 16:1ω5c) biomarkers was observed in the rhizosphere soil from day 1 to day 20 after labeling. The Gram negative (16:1ω7c) decreased and fungal (18:2ω6,9c) increased significantly in rhizospheric soil compared to bulk soil after day 1 of labeling. Whereas, after 20 days of labeling, the Gram negative biomarker (16:1ω7c and 18:1ω7c) decreased and Gram positive (a15:0) increased significantly in rhizospheric soil compared to bulk soil. One day following labeling, i15:0, a15:0, i16:0, 16:1ω5c, 16:0, i17:0, a17:0, 18:2ω6,9c, 18:1ω9c, and 18:0 PLFAs were significantly more enriched in δ13C in the rhizosphere than in the bulk soil. Twenty days after labeling, 16:1ω5c (Gram negative) and 18:2ω6,9c (fungal) were significantly more enriched in δ13C in the rhizosphere than in the bulk soil. These results shows the effectives of PLFA coupled using the pulse chase labeling technique to examine the microbial community changes in response to recently fixed photosynthetic C flow in rhizodeposits. 相似文献
138.
Miyuki Nakajima Shuirong Tang Yasuaki Hori Eiko Yaginuma Satoshi Hattori 《Soil Science and Plant Nutrition》2016,62(1):90-98
Submerged rice paddies are a major source of methane (CH4) which is the second most important greenhouse gas after carbon dioxide (CO2). Accelerating rice straw decomposition during the off-rice season could help to reduce CH4 emission from rice paddies during the single rice-growth season in cold temperate regions. For understanding how both temperature and moisture can affect the rate of rice straw decomposition during the off-rice season in the cold temperate region of Tohoku district, Japan, a modeling incubation experiment was carried out in the laboratory. Bulk soil and soil mixed with 2% of δ13C-labeled rice straw with a full factorial combination of four temperature levels (?5 to 5, 5, 15, 25°C) and two moisture levels (60% and 100% WFPS) were incubated for 24 weeks. The daily change from ?5 to 5°C was used to model the freezing–thawing cycles occurring during the winter season. The rates of rice straw decomposition were calculated by (i) CO2 production; (ii) change in the soil organic carbon (SOC) content; and (iii) change in the δ13C value of SOC. The results indicated that both temperature and moisture affected the rate of rice straw decomposition during the 24-week aerobic incubation period. Rates of rice straw decomposition increased not only with high temperature, but also with high moisture conditions. The rates of rice straw decomposition were more accurately calculated by CO2 production compared to those calculated by the change in the SOC content, or in its δ13C value. Under high moisture at 100% WFPS condition, the rates of rice straw decomposition were 14.0, 22.2, 33.5 and 46.2% at ?5 to 5, 5, 15 and 25°C temperature treatments, respectively. While under low moisture at 60% WFPS condition, these rates were 12.7, 18.3, 31.2 and 38.4%, respectively. The Q10 of rice straw decomposition was higher between ?5 to 5 and 5°C than that between 5 and 15°C and that between 15 and 25°C. Daily freezing–thawing cycles (from ?5 to 5°C) did not stimulate rice straw decomposition compared with low temperature at 5°C. This study implies that to reduce CH4 emission from rice paddies during the single rice-growth season in the cold temperate regions, enhancing rice straw decomposition during the high temperature period is very important. 相似文献
139.
以5年生苹果烟富3/M26/平邑甜茶为试材,研究了萘乙酸(NAA)、乙烯及6–苄基腺嘌呤(6-BA)对坐果和13C、15N利用分配的影响。结果表明:在中心果直径5 mm时(盛花后14 d)喷施10 mg ? L-1 NAA和600 mg ? L-1乙烯利的植株坐果率显著低于对照,而喷施100 mg ? L-1 6-BA的植株坐果率与对照差异不显著;NAA和乙烯利处理的植株13C和15N分配率规律一致,其果实13C分配率分别为1.11%和1.22%,15N分配率分别为0.39%和0.33%,显著低于对照(9.12%和7.29%),而根系和枝13C分配率和15N分配率显著高于对照;NAA和乙烯利处理的植株Ndff值表现规律一致,提高了叶片、根系和枝对15N的征调能力,降低果实对15N的征调能力;与对照相比,NAA和乙烯利处理的植株15N利用率显著增加了2.35和2.37个百分点,促进了根系、叶片和枝的生长和对氮同化物的征调能力,6-BA处理与对照差异不显著。 相似文献
140.
宁麦9号是江苏省农业科学院选育的优质弱筋专用小麦品种,具有高产、稳产和广泛的适应性及抗小麦黄花叶病、赤霉病等特点,近年来已成为江苏淮南麦区小麦育种的重要亲本。为了解宁麦9号对新育成小麦品种的遗传贡献,利用170对SSR引物,对宁麦9号及其9个衍生品种进行全基因组扫描分析。共检测到471个等位变异位点,每对引物可检测1~6个,平均2.8个。UPGMA聚类分析表明,扬麦18与宁麦9号遗传距离最小,扬辐麦4与宁麦9号遗传距离最大。遗传相似系数表明,在人工选择的作用下,这些以宁麦9号为亲本育成品种的遗传背景一半以上来自宁麦9号。宁麦9号等位变异在其衍生材料中的分布比例因品种而异,且不同染色体间差异较大,但相同位点的等位变异比例在A、B、D染色体组间相近。全基因组SSR扫描分析发现,10个标记位点在宁麦9号和由其选育的9个新品种具有完全相同的扩增带型,其中9个位点与重要农艺性状相关,或与控制优良性状的基因紧密连锁。将宁麦9号与主要弱筋小麦生产品种宁麦13(宁麦9号系选)进行基因组比较,两者遗传相似系数达0.732,说明宁麦13与宁麦9号遗传背景高度相似,而且两品种在蛋白质含量和抗赤霉病位点相关标记位点高度一致,这一结果可以部分解释宁麦13同样具有的抗赤霉病与优质弱筋的优点。 相似文献