水培甜瓜对营养液及主要矿质元素的吸收特性   总被引：3，自引：0，他引：3  

谭学文  刘增鑫 《华北农学报》1996,11(3):101-105

在ＤＦＴ栽培条件下，从定植到收获，甜瓜日平均吸收营养液０．４１Ｌ，定果后１０天内出现吸收峰值（１．１３Ｌ／株），收获前仍维持较高水平。不同生长时期内，甜瓜对钾、钙、镁、磷的吸收变化与甜瓜对营养液的吸收变化基本相似，营养生长时期，吸收量较少，授粉后吸收量急剧增加，在定果后１０天内出现吸收峰值，此后急剧减少，但甜瓜对钾的吸收峰值超前一周出现。根据甜瓜对主要大量元素的实际吸收浓度，可以推算甜瓜合适的营养液配方  相似文献   

甘薯品种抗旱适应性的数量分析   总被引：14，自引：2，他引：14  

谈锋  张启堂 《作物学报》1991,17(5):394-398

抗旱适应性的定量描述是甘薯品种抗旱性改良的基础工作。目前在甘薯品种抗旱形态指标筛选和抗旱适应性的生理机理方面只有少量研究,尚无抗旱适应性定量描述的报道。本文在测定六个甘薯品种十项抗旱形态生理指标的基础上,运用模糊数学关于隶属函数的方法对甘薯品种抗旱适应性的定量描述作了初步探索。  相似文献   

诱导百合鳞片芽的影响因子研究   总被引：4，自引：0，他引：4  

李黛  谈锋 《种子》2004,23(11):18-20

采用正交试验的方法,在MS固体培养基上研究鳞片位置和不同浓度蔗糖、6-BA(6-苄基腺嘌呤)及NAA(α-奈乙酸)对诱导淡黄花百合不定芽的影响.结果表明:最佳外植体为中层鳞片,最佳培养基为MS 0.5mg/L 6-BA 0.5mg/L～1 mg/L NAA 3%～5%蔗糖.  相似文献   

Modeling the relationship between the main emulsion components and stability, viscosity, fluid behavior, zeta-potential, and electrophoretic mobility of orange beverage emulsion using response surface methodology     

Mirhosseini H  Tan CP  Hamid NS  Yusof S 《Journal of agricultural and food chemistry》2007,55(19):7659-7666

The possible relationships between the main emulsion components (namely, Arabic gum, xanthan gum, and orange oil) and the physicochemical properties of orange beverage emulsion were evaluated by using response surface methodology. The physicochemical emulsion property variables considered as response variables were emulsion stability, viscosity, fluid behavior, zeta-potential, and electrophoretic mobility. The independent variables had the most and least significant ( p < 0.05) effect on viscosity and zeta-potential, respectively. The quadratic effect of orange oil and Arabic gum, the interaction effect of Arabic gum and xanthan gum, and the main effect of Arabic gum were the most significant ( p < 0.05) effects on turbidity loss rate, viscosity, viscosity ratio, and mobility, respectively. The main effect of Arabic gum was found to be significant ( p < 0.05) in all response variables except for turbidity loss rate. The nonlinear regression equations were significantly ( p < 0.05) fitted for all response variables with high R (2) values (>0.86), which had no indication of lack of fit. The results indicated that a combined level of 10.78% (w/w) Arabic gum, 0.56% (w/w) xanthan gum, and 15.27% (w/w) orange oil was predicted to provide the overall optimum region in terms of physicochemical properties studied. No significant ( p > 0.05) difference between the experimental and the predicted values confirmed the adequacy of response surface equations.  相似文献   

Tissue-specific effect of dietary cysteamine on expression of adiponectin receptors in rats     

Xu J  Shao W  Chi H  Tan Y  Zhao R 《Journal of agricultural and food chemistry》2007,55(19):7968-7973

  相似文献   

干旱区受损植被生态恢复需水量——以新疆哈巴河县平原区为例     

谭翻  杨鹏年  王翠  李志鹏  高凡  徐燕  吴强 《水土保持通报》2023,43(1):244-252

[目的]分析干旱区受损植被恢复过程中生态需水量,为生态恢复不同阶段所需水资源量及水资源优化配置提供科学依据。[方法]基于1990,2000,2010,2015,2020年Landsat系列影像,采用遥感技术,结合改进的彭曼公式法,对新疆哈巴河县平原区植被耗水量时空演变特征及生态恢复需水量进行了定量研究。[结果](1)1990—2020年天然植被平均耗水量为7.55×10⁸ m³,以3.60×10⁷ m³/5 a的速率减小,与之对应的是天然植被面积以17.36 km²/a的速率减小,植被覆盖度从高植被覆盖度向中植被覆盖度转化,生态受损严重。(2)区域内植被耗水量时空分布均存在较大差异：空间上高值主要分布于哈巴河流域,别列则克河流域植被耗水量整体偏低;时间上年际变化以2000年植被耗水量为最高,年内植被耗水量则主要集中在生长中期。(3)绿洲区生态恢复需水量如下：维持现状(2020年)生态需水量为4.62×10⁸ m³,恢复到1990—20...  相似文献   

Rhodococcus equi in the soil environment of horses in Inner Mongolia, China     

Takai S  Zhuang D  Huo XW  Madarame H  Gao MH  Tan ZT  Gao SC  Yan LJ  Guo CM  Zhou XF  Hatori F  Sasaki Y  Kakuda T  Tsubaki S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(7):739-742

Little is known about the distribution of Rhodococcus equi in the soil environment of native horses in China. One hundred and eight soil samples were collected from native-horse farms in the Hulun Beier grasslands of eastern Mongolia, the Xilin Goler grasslands of southern Mongolia, and Tongliao City in Inner Mongolia, China. The isolation rates of R. equi from soil samples from the Hulun Beier and Xilin Goler grasslands ranged from 25.9% to 30.0%. In contrast, isolation rates from soil samples from Tongliao City were as high as 82.3% and the mean number of R. equi in soil samples from Tongliao City was 10 times more than those of samples from the grasslands. The 488 isolates were examined using PCR for the presence of genes that encode virulence-associated 15-17 kDa antigen protein (VapA) and the 20 kDa antigen protein (VapB). All isolates were negative for virulence-associated proteins. Plasmid profiles of these avirulent isolates showed that cryptic plasmids of various sizes were present with an incidence of 13.3% to 21.5%. The results of the present study contrast with those of our recent study (J. Vet. Med. Sci. 67:611-613, 2005), in which we reported that R. equi was absent from Mongolian horses in Ulaanbaatar, Mongolia. It is suggested that the difference between the results of these two studies is due to the mobile pasturing system in Mongolia and nonmobile pasturing system in Inner Mongolia.  相似文献   

Anisotropy and corotation of galactic cosmic rays     

Amenomori M  Ayabe S  Bi XJ  Chen D  Cui SW  Danzengluobu  Ding LK  Ding XH  Feng CF  Feng Z  Feng ZY  Gao XY  Geng QX  Guo HW  He HH  He M  Hibino K  Hotta N  Hu H  Hu HB  Huang J  Huang Q  Jia HY  Kajino F  Kasahara K  Katayose Y  Kato C  Kawata K  Labaciren  Le GM  Li AF  Li JY  Lou YQ  Lu H  Lu SL  Meng XR  Mizutani K  Mu J  Munakata K  Nagai A  Nanjo H  Nishizawa M  Ohnishi M  Ohta I  Onuma H  Ouchi T  Ozawa S  Ren JR  Saito T  Saito TY  Sakata M  Sako TK  Sasaki T  Shibata M  Shiomi A  Shirai T  Sugimoto H  Takita M  Tan YH  Tateyama N  Torii S 《Science (New York, N.Y.)》2006,314(5798):439-443

The intensity of Galactic cosmic rays is nearly isotropic because of the influence of magnetic fields in the Milky Way. Here, we present two-dimensional high-precision anisotropy measurement for energies from a few to several hundred teraelectronvolts (TeV), using the large data sample of the Tibet Air Shower Arrays. Besides revealing finer details of the known anisotropies, a new component of Galactic cosmic ray anisotropy in sidereal time is uncovered around the Cygnus region direction. For cosmic-ray energies up to a few hundred TeV, all components of anisotropies fade away, showing a corotation of Galactic cosmic rays with the local Galactic magnetic environment. These results have broad implications for a comprehensive understanding of cosmic rays, supernovae, magnetic fields, and heliospheric and Galactic dynamic environments.  相似文献   

两种中药方剂对猪流感的防治效果比较试验     

谭德展  蒋小件 《中国饲料》2009,(15)

本文对自行研制的中草药方剂疏风清热散与银翘散对猪流感的防治效果进行对比试验.在猪流感抗体阴性试验场临床健康猪群中随机选取60头体重(约30 kg)和体况基本一致的猪,随机分成3个组,每组20头,第1组和第2组分别为疏风清热散和银翘散试验组,第3组为对照组(不给药).预防效果试验给药1/5荆/(d·头),粉碎均匀分2次拌入料中喂服;治疗效果试验给药1剂/(d·头),煎后分2次喂服,给药时间均为5 d.结果显示,两种方荆对预防和治疗猪流感均有较好效果.但疏风清热散的防治作用优于银翘散.  相似文献   

基于LMPSO-SVM的高光谱水稻稻瘟病害分级检测     

刘潭  李子默  冯帅  王雯琦  袁青云  许童羽 《农业机械学报》2023,54(11):208-216，235

为减少水稻产量损失,迫切需要建立快速、准确的水稻叶瘟监测和鉴别方法。本文以东北水稻为研究对象,以小区试验为基础,使用高光谱图像仪获取受稻瘟病菌侵染后不同发病程度的水稻叶片高光谱图像并提取光谱数据。首先,通过SG平滑方法对光谱数据进行预处理,然后运用主成分分析(PCA)、Pearson相关系数分析法(PCCs)、PLS-VIP方法对光谱数据进行降维,并提出了一种基于Logistic混沌映射PSO寻优的SVM分级检测模型(LMPSO-SVM)。为了验证提出方法的有效性,以不同降维方法提取的特征变量为输入,分别建立基于人工神经网络(ANN)、支持向量机(SVM)和PSO-SVM的分级模型并进行对比分析。仿真结果表明,各模型对4级病害的识别效果最好,综合5种级别病害,SVM和ANN分级模型的预测准确率波动相对较大,对于病害预测效果不太理想;而在不同特征选择下建立的LMPSO-SVM分级模型对各级病害预测准确率均较高,准确率波动较小,其中基于PCA提取特征变量和全波段作为输入的模型平均准确率非常相近,分别为96.49%和96.12%,PCA提取的输入变量仅为5个,大大简化了模型复杂性,降低了训练...  相似文献