利它素对中华通草蛉不同龄期幼虫捕食行为的影响

本文测定了棉蚜及棉花嫩梢不同溶剂提取液对中华通草蛉捕食行为的影响。结果表明，棉花受害嫩梢及未受害嫩梢提取液对中华通草蛉幼虫捕食行为无明显影响；棉蚜虫体浆液、棉蚜水提液，均含有很强的利它素活性物质，而棉蚜无水乙醇提取液利它素活性物质含量甚微，中华通草蛉各龄幼虫对棉蚜水提液均表现有明显的滞留和调转行为。     

果桑品种“大10”的引种与栽培

果用及果叶兼用桑品种大10，三倍体，由浙江省从广东省引进。经在浙江省种植表明，成林桑园每667m^2可产鲜果约1000kg，果型大、味甜，无籽；同时还可产桑叶约1600kg，桑叶养蚕叶质较好。耐寒性较弱，易感桑椹菌核病。     

杨梅属植物共生结瘤固氮研究进展

杨梅属35个种中有28个种能与Frankia放线菌共生结瘤固氮。根据有关文献从杨梅属植物共生固氮根瘤及其内生放线菌的形态结构、杨梅属植物根瘤内生放线菌的分类地位、杨梅属植物共生固氮放线菌的生理生化特性、环境条件对杨梅属植物根瘤共生固氮的影响以及分子生物学方法在杨梅属植物根瘤共生固氮放线菌中的应用等方面作了较为详细的阐述。     

基于玄府气液理论探讨溻渍法的作用机制

本文通过深入分析玄府气液理论,并在玄府气液理论指导下探讨溻渍法的作用机制,初步解释溻渍法治疗诸多疾病的作用机制在于注重辛味药物通过肌肤毛窍、孔穴腠理等部位发散外邪,气血调和以直接宣通玄府气液通道,以及调燮五脏六腑之气以间接宣通玄府气液通道。     

Effects of Exogenous 24-epibrassinolide on Photosynthetic Physiology of CottonSeedlings under Low Temperature

[Objective] The objective of this study was to investigate the effects of exogenous 24-epibrassinolide (EBR) on the photosynthetic physiology of cotton seedlings under low temperature and to provide basis for improving the cold tolerance of cotton by using EBR as growth regulator. [Method] Taking CCRI 60, Lumianyan 28 and Simian 3 as materials, a field experiment was carried out in Institute of Cotton Research of CAAS(Anyang county, Henan province). Before the first low temperature treatment, the cotton seedlings were sprayed with distilled water (Control) and different concentrations of EBR (0.1 mg·L^－1 and 0.2 mg·L^－1), respectively. After 3 days, the relative electrical conductivity, chlorophyll content, rapid chlorophyll fluorescence induction kinetic curve (OJIP) and fluorescence parameters were measured. [Result] Under low temperature, the relative conductivity of CCRI 60, Lumianyan 28 and Simian 3 spraying with EBR decreased by 17.7%～32.8% compared with control, and there was no significant difference between CCRI 60 and Lumianyan 28 in different concentrations of EBR treatments, butthe relative conductivity of Simian 3 treating with 0.2 mg·L^－1 EBR was significantly lower than those treatments with 0.1 mg·L^－1 EBR . The chl a and chl b contents increased by 9.7%～32.6% and 15.0%～18.9%, respectively. The maximum photochemical efficiency of photosystemⅡ (F_v/F_M) and photosynthetic performance index on absorption basis(PI_ABS) increased significantly. PI_ABS of CCRI 60 increase the maximum by 75.6% using 0.1 mg·L^－1 EBR. Lumianyan 28 and Simian 3 increased the maximum by 101.1% and 265.6% using 0.2 mg·L^－1 EBR, respectively; Absorbed photon flux per cross section (ABS/CSm), electron transport flux (further than QA) per active reactive center (ETo/RC) and probability for electron transport (φEo) are significantly increased. [Conclusion] Exogenous EBR can enhance the ability of low temperature tolerance of cotton seedlings and alleviate the inhibition of photosynthesis in cotton at low temperature. The study showed that 0.1 mg·L^－1 EBR performs well in CCRI 60 and 0.2 mg·L^－1 in Lumianyan 28 and Simian 3.     

基于HOG特征的IKSVM稻瘟病孢子检测

为解决稻瘟病孢子的人工检测过程中主观性强、自动化程度低、效率低等问题,提出一种基于梯度方向直方图特征（HOG特征）的加性交叉核支持向量机（IKSVM）的稻瘟病孢子检测方法。该方法首先利用图像采集系统采集稻瘟病孢子图像,利用Gamma校正法调节图像的对比度,抑制噪声干扰;然后,提取孢子图像的HOG特征作为输入向量,输入到支持向量机中,构建加性交叉核支持向量机分类器;最后,通过训练得到稻瘟病孢子分类器。为测试所提出的HOG/IKSVM方法的综合性能,分别选用HOG/线性SVM方法与HOG/径向基核SVM（HOG/RBF-SVM）方法做对比试验。试验结果表明,HOG/IKSVM的检测率为98.2%,高于HOG/线性SVM方法的79%;在平均检测时间上,HOG/IKSVM方法的平均检测耗时仅为HOG/RBF-SVM方法的1.1%。说明该方法可以进行稻瘟病孢子室内检测识别。     

Temporal change in soil macropores measured using tension infiltrometer under different land uses and slope positions in subtropical China

Purpose

Soil macropores play a principal role in water infiltration but they are highly variable. The objectives of this study were (1) to investigate the temporal change in macropores of an Ultisol as affected by land use and slope position and (2) to analyze contribution of macropores to water infiltration.

Materials and methods

Water infiltration was measured at upper and lower slopes in citrus orchard and watermelon field once every 2 months for 1 year using tension infiltrometers at a successive pressure head from ?12, ?6, ?3, to 0 hPa.

Results and discussion

Hydraulic conductivity (K) was significantly affected by land use and slope position except at 0 hPa pressure head, showing a significant temporal variation. Effective macroporosity, derived from the increment of hydraulic conductivity between ?3 and 0 hPa, showed a significant temporal variation. Such temporal variation was land use (P?<?0.05) and slope position (P?<?0.001) dependent. Despite of low proportion in total soil volume (averaged 3.5 cm³ m^?3), the macropores contributed 47 % of water flux on average. The macroporosity was more stable and higher in the citrus orchard (2.43 cm³ m^?3, coefficient of variance (CV)?=?75 %) than in the watermelon field (1.72 cm³ m^?3, CV?=?117 %) and contributed more to infiltration in the citrus orchard (60 %, CV?=?16 %) than in the watermelon field (33 %, CV?=?43 %) as well, because tillage was operated only in the watermelon field.

Conclusions

No-tillage increased water conducting macropores but did not increase hydraulic conductivity irrespective of slope position.

     

转 Hoxc13基因绵羊的羊毛氨基酸组成及含硫量和含氮量分析

为评估转Hoxc13基因绵羊的羊毛化学特性,以中国美利奴(新疆军垦型)超细毛品系为对照组,转Hoxc13基因绵羊为试验组,应用水解法测定羊毛17种氨基酸,质量法测定羊毛含硫量,凯氏定氮法测量羊毛含氮量。结果表明,转Hoxc13基因绵羊的羊毛中天门冬氨酸、苏氨酸、丝氨酸、谷氨酸、脯氨酸、甘氨酸、丙氨酸、胱氨酸、缬氨酸、异亮氨酸、亮氨酸、酪氨酸、赖氨酸、组氨酸、苯丙氨酸和精氨酸的含量与对照组差异不显著(P>0.05),蛋氨酸的含量显著低于对照组(P<0.05),羊毛含硫量与对照组差异不显著(P>0.05),羊毛含氮量显著高于对照组(P<0.05)。以上结果说明,转Hoxc13基因绵羊的羊毛化学成分没有明显改变。     

林带连续性经济效益模型及其应用的研究

通过对农田防护林经营问题的深入系统的探讨,以阐明农田防护林考虑时空动态特征的连续性的经济效益为目标,在建立主要决定因素包括林带结构一疏透度变化规律,林带结构对防护效益影响。