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101.
102.
干旱胁迫和复水对夏蜡梅幼苗光合生理特性的影响 总被引:9,自引:0,他引:9
以盆栽二年生夏蜡梅(Sinocalycanthus.chinensis)实生苗为材料,分对照、轻度胁迫、中度胁迫和重度胁迫4组,研究了不同程度干旱胁迫和复水对夏蜡梅光合特性的影响。结果表明,在干旱胁迫下,夏蜡梅的光合日变化曲线由典型的双峰型转变为峰值很小的单峰型。在较高强度的干旱胁迫下,夏蜡梅光补偿点、CO2补偿点和气孔阻力升高,光饱和点、表观量子效率、最大净光合速率、羧化效率、Fv/Fm和蒸腾速率下降;而暗呼吸速率先升后降、胞间CO2浓度先降后升。轻度和中度干旱胁迫下光合能力的下降主要由气孔限制引起,而在重度胁迫下则由非气孔限制起主要作用。重度胁迫复水3d后,夏蜡梅的光合能力恢复很弱。过分干旱胁迫对夏蜡梅造成一定伤害。 相似文献
103.
邓军 《江西农业大学学报》2006,28(4):625-629
物流管理是供应链管理的核心,是制造企业迅速组织生产的关键。基于供应链上的各种对象与G IS的关系,指出了物流技术与空间信息技术融合成物流空间信息技术的必然性;提出了采用总线型G IS模型作为物流空间信息系统的结构模型,并由此进行物流空间信息的组织体系的构架设计,该构架充分利用了中间件热插拔的特性,能够很好地满足物流空间信息所涉及的异构分布式复杂信息集成要求。 相似文献
104.
105.
根据1998-2003年杂交水稻黑条矮缩病发生为害损失与防治指标研究,测定了杂交水稻不同组合、不同生育期的发病率,以及秧苗期与大田期的侵染机率,分析了杂交水稻黑条矮缩病前后作发病率关系:M=1.6822m 0.1049,以及株发病率(M%)与产量损失率(Y%)的关系:Y=0.9776M-0.1935;阐述了灰飞虱不同虫量(X)与发病率和产量损失率(Y%)的关系:秧苗期为Y1=12.1841X1-1.0784,大田前期为Y2=4.5159X2-0.4620。在拟定经济允许损失水平的基础上,提出杂交水稻秧苗2-5叶期和大田初期为防治适期,并制定杂交水稻黑条矮缩病的策略性防治指标为前作穗期防治的黑条矮缩痛株发病率1.0%,制定秧苗期防治指标为带毒灰飞虱0.15只/0.11m2、大田初期防治指标为带毒灰飞虱4000只/667m2(百丛带毒灰飞虱20只)。经应用验证,与实际基本吻合。 相似文献
106.
为云锦杜鹃的合理开发和引种栽培提供科学依据。以5年生云锦杜鹃苗木为材料,通过盆栽试验,模拟四种不同程度的土壤水分胁迫:对照(最大田间持水量MFA 75%~80%下同)、轻度胁迫(MFA 60%~65%)、中度胁迫(MFA 45%~50%)、重度胁迫(MFA 30%~35%),研究土壤水分胁迫对云锦杜鹃的气孔导度和蒸腾速率的影响。在轻度、中度、重度胁迫下,蒸腾速率和气孔导度与对照相比分别降低了21%和33%、65%和44%、67%和82%,气孔导度的下降幅度比蒸腾速率大,云锦杜鹃蒸腾速率日变化曲线为单峰型,而气孔导度日变化曲线为双峰型。经逐步多元回归得到了不同水分处理下蒸腾速率日变化与生态因子的回归方程。蒸腾速率与气孔导度、土壤含水量和叶片相对含水量关系密切。 相似文献
107.
KEShi-sheng 《中国农业科学(英文版)》2007,6(10):1182-1192
The objective of the present study was to gain better insight into the physiological mechanisms on the effects of copper (Cu) on photosynthesis and active oxygen metabolism in three-colored amaranth plant (Amaranthus tricolor). Three-colored amaranth seedlings were subjected to different Cu levels in soils during the entire experimental period. The parameters of growth, photosynthesis, mineral elements contents, and active oxygen metabolism were investigated using plant physiological methods. The results showed that 2.0 and 4.0 mmol Cu kg−1 treatments decreased the whole plant biomass to 91 and 73% of the control, respectively. The net photosynthetic rate (Pn) and the stomatal conductance (gs) were similarly reduced in the third leaves of three-colored amaranth seedlings treated with 2.0 and 4.0 mmol Cu kg-1 soil, respectively. None of the investigated Cu levels decreased the internal CO2 concentration (Ci). The effect of Cu on the potential efficiency of photosystem II (FvIFm) was negligible, whereas the effect of Cu on the PS II quantum efficiency (ΦPS II) after plant adaptation in actinic irradiation was more noticeable. On the other hand, decreases in water percentage, contents of photosynthetic pigments and mineral elements including Fe, K, and Mg, and significant increase in the Cu content were observed in the third leaves of Cu-treated plants. Superoxide dismutase (SOD) and peroxidase (POD) activities as well as the proline (Pro) content significantly increased in the third leaves of the three-colored amaranth seedlings treated with 2.0 and 4.0 mmol Cu kg−1 soil, while catalase (CAT) and ascorbate peroxidase (APX) activities as well as the contents of carotenoid (Car), glutathione (GSH), and ascorbic acid (AsA) decreased, and accompanied by the increases in the contents of hydrogen peroxide (H2O2), superoxide anion (O2.-), and malondialdehyde (MDA), and electrolyte leakage. As a result of the imbalance of active oxygen metabolism, Pn and ΦPS II decreased, and peroxidization enhanced under levels of 2.0 and 4.0 mmol Cu kg−1 soil. Finally, the growth of three-colored amaranth plant was significantly inhibited. 相似文献
108.
为探究农业废弃物的氮肥替代能力及后效肥力,于早稻季进行4种等氮处理,即单施化肥(CK)、稻草+化肥(SF)、水葫芦+化肥(HF)和西兰花茎叶+化肥(BF),以不施氮肥作对照(CK0);晚稻季仅在SF、HF和BF处理小区内进行稻草还田。早稻以台早733、晚稻以中浙优8号和甬优1540为材料,考察不同处理对水稻产量、品质及土壤肥力的影响。结果表明,农业废弃物与化肥减量配施可提高氮肥利用率和水稻产量,SF、HF和BF处理的晚稻产量分别较CK处理提高5.3%、7.2%和7.6%,其周年产量分别提高-1.7%、3.5%和8.1%;并可改善晚稻的稻米加工品质、外观品质和食味品质,主要提高其糙米率、精米率和整精米率,降低垩白粒率、垩白度(中浙优8号)和蛋白质含量;提高土壤有机质、全氮、有效磷和速效钾含量,降低土壤容重,并缓解土壤酸化。综上,农业废弃物与化肥减量配施利于水稻高产稳产、改善稻米品质和提升土壤肥力,其中以BF处理效果最佳。 相似文献
109.
浙江甘薯蔓枯病病原菌鉴定 总被引:1,自引:0,他引:1
Recent years, gummy stem blight caused by Diaporthe spp. is an important disease on Ipomoea batatas. In this study, infected plant tissues, collected from Ningxi, Taizhou, were used for isolating pathogens from the gummy stem. Three pure strains with similar cultural characteristics were isolated, tested for their pathogenicity against stems of I. batatas, and re-isolated from the tissue inoculated, and Koch's postulate was fulfilled. The rRNA intergenic spacer (ITS) region of these isolates was amplified and the sequences were used for the phylogenetic analysis. The aliment result showed that the sequences (MT107556, MT107557 and MT107558) of three strains were 100% similarity with that of D. batatas CBS 122.21. These isolates were identified as D. batatas based on the morphological and molecular characteristics. Therefore, gummy stem blight on Ipomoea batatas was caused by D. batatas in Zhejiang province. Meanwhile, this study firstly showed that the stroma of D. batatas was coralloid. 相似文献
110.
AIM:To study the effects of recombinant adeno-associated virus type 1 (rAAV1)-sarcoplasmic/endoplasmic reticulum calcium ATPase 2a (SERCA2a) transfection on the cardiac function of beagles with heart failure (HF). METHODS:The beagles were used to make an animal model with heart failure after rapid right ventricular pacing (230 beats/min) for 30 d. A reduced rate (180 beats/min) was continuously applied for another 30 d. The beagles were divided into 4 groups (n=4): control group, HF group, HF+EGFP group and HF+SERCA2a group. rAAV1-EGFP and rAAV1-SERCA2a (both 1×1012 viral genomes) were intramyocardially injected into the animals in the latter 2 groups, respectively. RESULTS:After transfection for 30 d, the left ventricular systolic function in HF+SERCA2a group was similar to that in control group, and significantly higher than that in HF group (P<0.05). The ratio of SERCA2a mRNA/GAPDH mRNA was significantly higher in HF+SERCA2a group than that in HF group (P<0.05). The expression level of SERCA2a in the myocardial tissues was higher in HF+SERCA2a group than that in HF group (P<0.05). The apoptotic index of the cardiomyocytes and the protein expression of MMP-9 were much lower in HF+ SERCA2a group than those in HF group (P<0.05). No significant difference of all parameters was observed between HF group and HF+EGFP group. The mRNA level of phospholamban was unchanged. CONCLUSION:Transfection of SERCA2a improves the expression of SERCA2a, restores the cardiac function and inhibits left ventricular remodeling by reducing the cardiac cell apoptosis and the MMP-9 expression in the heart failure beagles. 相似文献