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991.
从宏观发展的视角分析我国现代芽菜产业链的内涵和概念、发展历程和特征,从社会经济学角度分析现代芽菜产业链的构建及其功能效应,展望了现代生物科技系统地应用于规模化芽莱产业,对培植和提升我国现代芽菜产业主体创新能力的重要意义。 相似文献
992.
基于北京市果类蔬菜种植户的实地调研数据,运用描述性统计分析方法,对北京市果类蔬菜生产经营的基本特征进行了分析,在此基础上探究了种植规模、种植技术、流通情况、市场基础建设、农民专业合作社和蔬菜生产支持政策对果类蔬菜生产经营所产生的影响。进一步地,将两个不同年度的果类蔬菜生产情况进行对比,从动态视角研究了近四年北京市果类蔬菜生产的发展变化。主要研究结论为:(1)北京市果类蔬菜生产经营主体主要为小规模农户;(2)蔬菜种植户的老龄化趋势明显;(3)农户对于种菜新技术的需求不断增长;(4)土地规模、种菜技术、市场基础建设和政府政策均对蔬菜生产有着显著正向影响;(5)政府对果类蔬菜产业的支持力度持续增大。 相似文献
993.
ZHAO Shuang KANG Yu-ming ZHANG Sheng-chang WANG Shu-qiu WANG Shao-qing MA Xiao-ru ZHANG Ting 《园艺学报》2007,23(6):1153-1156
AIM: To investigate the effect of Ganoderma lucidum spores powder on the expression of insulin-like growth factor-1 (IGF-1), nuclear factor-κB (NF-κB) and apoptosis of nerve cells in rats with epilepsy established by pentetrazole. METHODS: The sub-eclampsia dosage of pentetrazole (PTZ) was used to make epilepsy model. Ganoderma lucidum spores powder group was given from stomach. The enduring time and latent period were recorded. The immune reactivity of IGF-1, NF-κB/P65 and apoptosis of nerve cells were measured with immunohistochemical staining and TUNEL method. RESULTS: In high power sight (×400), there were much more apoptosis cells in hippocampus and brain cortex of model group (18.80±2.13, 16.87±2.00) than those in control group (0.97±0.52, 0.58±0.25). The expressions of IGF-1, NF-κB in model group were higher than those in control group. Compared with model group, the latent period of Ganoderma lucidum spores powder group at the 17th, 21th, 25th days were longer (P<0.05, P<0.05, P<0.01, respectively).There were less apoptosis cells in hippocampus and brain cortex of Ganoderma lucidum spores powder group (12.30±2.46, 10.48±1.33) than those in model group. The expression of NF-κB/P65 in Ganoderma lucidum spores powder group was lower than that in model group, but the immune reactivity of IGF-1 increased more distinctly in Ganoderma lucidum spores powder group than that in model group. CONCLUSION: IGF-1, NF-κB and apoptosis of nerve cells may have play a role in occurrence and development of PTZ-induced epilepsy. Ganoderma lucidum spores powder can suppress expression of NF-κB strongly, and facilitate the immune reactivity of IGF-1, which may be one of the mechanisms by which Ganoderma lucidum spores powder restrains the apoptosis of nerve cells caused by epilepsy to prevent the damages of nerve cells. 相似文献
994.
瓜叶菊耐热无性系离体筛选初步研究 总被引:3,自引:0,他引:3
以编号为B1 、N1 、Z1的瓜叶菊增殖期的愈伤组织和丛生芽为材料,用高温胁迫和羟脯氨酸 (HYP)分别作为直接和间接选择压,进行了瓜叶菊耐热无性系的离体筛选研究。结果表明:⑴ 离体直接筛选的适宜选择压为40℃16-20 h,HYP)间接筛选的适宜浓度为30m mmol·L-1;⑵ 经过直接选择、HYP与高温胁迫结合多次筛选获得了Z1-1-1和 N1-2-1 两个耐热无性系;⑶ Z1-1-1 与对照母株Z1在叶片厚度、气孔指数、栅栏组织厚度/海绵组织厚度(TPT/TST)方面存在显著差异,成年植株Z1-1-1 和Z1在花的育性上也差异明显,Z1结实率85%以上,而Z1-1-1在人工授粉的情况下结实率也仅1.0%;N1-2-1和其对照母株N1在形态和花的育性上没有明显差别;⑷ 在40℃24 h胁迫后,Z1-1-1和 N1-2-1的热害指数、细胞丙二醛含量、电解质伤害性外漏率都低于其对照母株,而POD、SOD活性明显高于其对照母株。 相似文献
995.
996.
植物内生放线菌防治西葫芦白粉病的初步研究 总被引:4,自引:0,他引:4
以西葫芦白粉病为对象,通过温室盆栽试验和叶盘筛选试验,从50个内生放线菌菌株中筛选出2个防病效果较好的菌株,叶盘筛选试验发现菌株GKSHJA和PR1-8的无菌滤液原液在接种病菌的同时使用防治效果最佳,分别达到60.98%和63.22%。温室人工接种白粉病菌的盆栽试验发现,GKSHJA无菌滤液原液在接种前、接种后24 h喷雾,相对防治效果分别达55.22%和16.44%;菌株PR1-8的相对防效分别为51.94%和24.39%,且GKSHJA和PR1-8无菌滤液的5倍稀释液在接种病菌的同时使用也有一定的防病效果,其病情指数分别比对照降低了27.81%和30.19%。在自然感病的田间试验中,菌株GKSHJA和PR1-8无菌滤液的5倍稀释液对西葫芦白粉病的相对防效分别达到56.33%和69.88%。这些结果表明,菌株GKSHJA和PR1-8作为防治瓜类白粉病的生防菌株,具有开发应用潜力和前景。 相似文献
997.
摘要:为研究冀中南地区小葱氮、磷、钾最佳施用量,以“青叶1号”为试材,采用“3414”肥效试 验方案,研究不同氮(N)、磷(P2O5)、钾(K2O)配比施肥对小葱产量、可溶性糖和叶片SPAD值的影 响,并运用一元二次和三元二次肥效效应函数得出冀中南地区小葱最佳施肥量。结果表明:氮肥中等水平 的小葱叶片SPAD值和可溶性固形物含量均最大,分别为26.3和20.0%;单种肥料对小葱的增产顺序依次为 氮>钾>磷,而产投比顺序依次为钾>氮>磷;氮、磷、钾施用量均为中等水平时,小葱产量达到最佳, 为63 860.3 kg/hm2 。在本试验条件下,推荐冀中南地区小葱经济效益最佳施肥量为N 456.0 kg/hm2 、P2O5 158.3 kg/hm2 、K2O 233.3 kg/hm2 。 相似文献
998.
999.
1000.
SUN Kai CHEN Wen-hua ZHANG Ying LI Yan AN Meng-yao PAN Ying-ying WU Yan-na KANG Yi GAO Wei-zhen LOU Jian-shi 《园艺学报》2017,33(1):116-122
AIM: To study the effects of noninvasive delayed limb ischemia preconditioning (NDLIP) on animal cardiac function, myocardial morphology and myocardial apoptosis after myocardial infarction (MI). METHODS: Healthy SD male rats[n=45, weighing (250±10) g] were randomly divided into 3 groups:MI group:the animal model of MI was established by surgical ligation of left anterior descending artery (LAD) after 2 weeks; NDLIP group:after the success of the MI animal model, NDLIP was carried out every other day until the 4th, 6th and 8th weeks; sham group:as the negative control group, the animals were taken heart LAD threading but no ligation. All rats were fed conventionally. At the end of the 4th, 6th and 8th weeks, all rats were made ventricular intubation, and then the hemodynamic parameters were recorded. The blood samples were withdrawn from the abdominal aorta and the serum was separated via centrifugation. The serum contents of Bcl-2 and Bax were measured by ELISA. Left ventricular anterior wall was homogenized. The mitochondrial respiratory chain complexes Ⅰ, Ⅱ, Ⅲ and Ⅳ in the myocardial tissues were detected by ELISA. RESULTS: At the end of the 4th, 6th and 8th weeks, compared with MI group, left ventricular systolic pressure in NDLIP group was significantly increased, while left ventricular end-diastolic pressure in NDLIP group was significantly decreased (both P<0.05). Mitochondrial respiratory chain complexesⅠ, Ⅱ, Ⅲ and Ⅳ in NDLIP group were significantly increased (P<0.05). The serum level of Bcl-2 in NDLIP group was significantly increased and Bax level was reduced remarkably (both P<0.01). CONCLUSION: NDLIP improves the hemodynamic indexes, promotes the mitochondrial respiratory function and inhibits cell apoptosis, thus improving the prognosis of MI. 相似文献