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61.
Juan Jin Huimei Cui Xinmin Lv Yifan Yang Yi Wang 《The Journal of Horticultural Science and Biotechnology》2017,92(1):98-106
In this study, we investigated the effects of 10 mM CaCl2 on membrane permeability, malondialdehyde (MDA), reactive oxygen species (ROS), and Na+, K+, Ca2+, and Mg2+ concentrations in different organs of sour jujube grown under 150 mM NaCl stress. Our results showed 73% leaf wilting in the Na treatment. The Na treatment significantly increased leaf superoxide (O2.?) production rates, hydrogen peroxide (H2O2) concentrations, cell membrane permeability, MDA concentrations, and Na+ concentrations in roots, stems, and leaves. The Na treatment significantly reduced K+, Ca2+,and Mg2+ concentrations in roots, but increased K+ concentrations in stems. Compared with the Na treatment, 39% of the leaves showed wilting symptoms in the Na+Ca treatment. The Na+Ca treatment significantly decreased leaf O2.? production rates, H2O2 concentrations, cell membrane permeability, and MDA concentrations. Moreover, the Na+Ca treatment (1) significantly reduced Na+ concentrations in roots, stems, and leaves; (2) significantly increased root K+ concentrations; (3) significantly increased K+/Na+ ratios in roots; (4) significantly increased Ca2+ concentrations in stems and leaves, and Mg2+ concentrations in roots. In conclusion, exogenous CaCl2 reduces NaCl stress in sour jujube by reducing Na+ concentrations and increasing K+, Ca2+, and Mg2+ concentrations in various plant organs. 相似文献
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采用抑菌圈法,对10种杀细菌剂在火龙果茎腐病病原上进行了毒力测定。结果表明:72%农用硫酸链霉素可溶粉剂、53.8%氢氧化铜水分散颗粒剂(杜邦TM)、45%代森铵水剂、47%春雷?王铜可湿性粉剂、50%福美双可湿性粉剂和3%中生菌素可湿性粉剂对火龙果茎腐病病原均有一定抑制效果。其中,45%代森铵水剂和50%福美双可湿性粉剂防治效果较好,抑制率分别达到78.88%和71.42%,其直线回归方程分别为y=2.380 2.477x,y=2.896 1.146x,EC50分别为0.4929,0.0240。72%农用硫酸链霉素可溶粉剂效果次之,抑制率达到66.67%,直线回归方程为y=1.020 1.040x,EC50值为2.5686。这3种药剂可作为火龙果茎腐病田间药效试验的首选药剂。 相似文献
64.
Four fungicides for seed treatments and one as foliar spray were tested in replicated field experiments in a strip plot design to determine the effect of fungicides on Helminthosporium leaf blight (caused by Cochliobolus sativus and Pyrenophora tritici-repentis) severity and grain yield of wheat. Wheat seed cv. RR 21 was treated with fungicides, carbendazim (Areestin), triadimenol (Baytan), tebuconazole (Raxil), and carboxin + thiram (Vitavax 200B). Single foliar application of propiconazole (Tilt) was sprayed at flowering stage. Controls were included for both factors and treatments were replicated four times. Triadimenol and carboxin + thiram increased seed germination in both years. Triadimenol, tebuconazole, and carboxin + thiram reduced the number of infected seedlings and seedling root rot severity in both years. Number of tillers was higher in carboxin + thiram treated plots compared to other seed treatments. Compared to the control, carboxin + thiram increased grain yield by 9% and 8% in 2004 and 2005, respectively, and triadimenol by 6% in both years. The foliar spray of propiconazole significantly reduced Helminthosporium leaf blight severity and increased thousand-kernel weights. Propiconazole spray increased grain yield by 15% and 14% in 2004 and 2005, respectively. Therefore, seed treatment either with triadimenol or carboxin + thiram in combination with single post-flowering foliar spray of fungicides should minimize grain yield loss due to wheat foliar blight in South Asia. The findings of this study could be useful in developing strategies to manage Helminthosporium leaf blight in South Asia and other warm wheat growing regions of the world. 相似文献
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Sexton, Z.S., Hughes, T.J., and Wise, K.A. 20XX. Analyzing isolate variability of Macrophomina phaseolina from a regional perspective. Crop Protection. XX:XXXX. Charcoal rot of soybean (Glycine max L.), caused by Macrophomina phaseolina (Tassi) Goid, has been reported more frequently in the north–central United States in recent years. Growth of isolates collected from the northern and southern U.S. was compared in vitro under various incubation temperatures, and isolate pathogenicity was assessed on cultivars adapted to each region. Results indicate that northern isolates had increased growth at 15 °C compared to isolates from southern states, while southern isolates grew 23% more at 40°C compared to northern isolates. Isolates from both regions were pathogenic on charcoal rot resistant and susceptible cultivars adapted for each region. This is the first research to suggest the importance of screening germplasm under regional environmental conditions and with local or regionally adapted isolates when evaluating cultivar resistance to charcoal rot. 相似文献
67.
Florida strawberry farmers usually rely on weekly calendar fungicide applications to prevent yield loss from Botrytis fruit rot (BFR). The Strawberry Advisory System (SAS), which helps optimize the timing of fungicide applications, is an additional tool in the farmers' arsenal of disease control options. This study uses data from two-year production trials in Florida combined with historical strawberry prices to measure the economic performance of the Calendar and SAS-based BFR management practices under output price risk and producers' risk preferences. We use Monte Carlo simulation to model the effect of the variability in weekly output prices on farm returns. Results reveal that the traditional calendar-based system is not the least risky BFR management option as growers expected to be. SAS-based options such as SAS-Switch and SAS-Luna would be preferred by both risk-neutral and risk-averse producers and are recommended under high disease pressure conditions. 相似文献
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69.
Rotfinder is a non-destructive decay-sensing apparatus based on resistance measurements in standing trees. The accuracy of Rotfinder in detecting decay was evaluated in 500 standing trees in three Norway spruce (Picea abies) plots. Trees were measured at three heights, 0.30, 0.66 and 1.30 m. Sections were later inspected for the presence of decay and reaction zones. Inspected trees were mostly infected by Heterobasidion annosum and showed a large variation in the amount of decay present, ranging from 0.1% to 88.0% of the section. Correctly and incorrectly classified trees were compared in terms of ion and element concentration, density and moisture. Measurements at stump level (0.30 m) were more accurate than measurements at breast height (1.30 m) where the reaction zone and decay columns showed lower moisture content. The accuracy of Rotfinder increased when trees with small decay columns were regarded as ‘non-decayed’. When only trees with more than 15% of the section decayed were regarded as ‘decayed’, Rotfinder had an accuracy of 0.86 when performing assessments at stump level. False negatives, as opposed to true positives, corresponded to trees with smaller and drier decay columns, drier reaction zones and lower K+ (potassium) concentration in the decay column. False positives corresponded to trees with large sapwood and high sodium content in the sapwood. Rotfinder represents an alternative to the standard method of using increment core observations to assess decay in living trees. 相似文献
70.
甘兰型油菜品质性状的变化与抗(耐)菌核病的关系 总被引:1,自引:0,他引:1
经1987~1992年时甘兰型油菜品质资源田间自然抗病性的连续观察鉴定(包括同一品种不同品质的单株)和同一品种不同发病级别单株种子内芥酸、硫甙、油份等品质的测试分析。结果是油菜菌核病的发病程度与这些品质性状的关系密切。即抗病性的强弱与芥酸、硫甙的含量成正相关,与油份的含量成反相关,不同发病级别的单株种子与产油量成反相关。根据分析结果笔者认为,在进行双低油菜育种过程中,应将低代材料置于易于发生菌核病的环境中选择,在发病极度严重时还要注重保留那些耐病的单株,这是集优质、丰产、耐病为一体的有效途径。同时在优质油菜生产中要作好防病工作。 相似文献