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为评价地熊蜂在重庆地区设施番茄的授粉效果,在重庆市荣昌区龙舌嘴村开展授粉效果比较试验,分析地熊蜂授粉对设施番茄产量、果实品质及畸形果率的影响。试验结果显示,经地熊蜂授粉的设施番茄平均产量为2 206.44 kg/667 m2,与未授粉组相比显著提高了104.95%,授粉组的单果质量、果纵径、果最大横径、可溶性固形物含量、VC含量及总糖含量显著高于未授粉组。由此,认为地熊蜂适宜为重庆地区设施番茄授粉,且能够显著提高重庆地区设施番茄的产量与品质。 相似文献
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【目的】研究人工采挖和自然坡度对冬虫夏草数量的影响。【方法】通过对不同采挖强度 S1 (2 人/hm2 )、S2 (4 人/hm2 )和 S3 (6 人/hm2 )和产区自然坡度(G1,7°;G2,17°;G3,25°)下冬虫夏草幼虫数量和采挖数量进行调查,分析采挖强度和产区坡度对幼虫数量和冬虫夏草采挖量的影响。【结果】采挖强度和坡度与幼虫数量和冬虫夏草采挖数量均呈显著负相关关系(P<0. 05);采挖强度和幼虫数量相关度高(r 2 =-0. 45,r 2 =-0. 58),坡度和冬虫夏草采挖数量相关度高(r 2 =-0. 74,r 2 =-0. 78),采挖强度和坡度互作对幼虫数量和采挖数量影响不显著(P>0. 05)。不同采挖强度下,幼虫数量和冬虫夏草采挖数量均为 CK=S1>S2>S3( P<0. 05);不同坡度下,幼虫数量和冬虫夏草采挖数量均为 CK=G1>G2> G3( P<0. 05);且在各个采挖强度下,随坡度的增加,幼虫数量和冬虫夏草采挖数量均呈显著降低趋势 (P<0. 05)。 此外 ,冬虫夏草采挖数量显著地受蝙蝠蛾幼虫数量的影响且呈正相关(P<0. 05)。 【结论】 S1采挖强度、G1小坡度适合幼虫数量的增长和冬虫夏草的采挖数量,且不影响翌年冬虫夏草的产量。然而,采挖活动有可能对草地的土壤、幼虫喜食性牧草、冬虫夏草真菌孢子的弹射等产生综合影响,土壤的理化性质会影响蝠蛾寄主幼虫的存活状态,冬虫夏草菌孢子的弹射量也会影响冬虫夏草的形成。 相似文献
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HUANG Zeng-yan HUANG Man-ping PENG Chun-li LIU Yong-yuan LI Chun-yan LIANG Dong-hui 《园艺学报》2021,37(1):34-40
AIM To observe effects of emotional stimulation on expression of stromal cell-derived factor-1(SDF-1) and CXC chemokine receptor 4 (CXCR4) in plasma, platelets, aortas, hippocampus and bone marrow of apolipoprotein E gene knockout (ApoE -/-) mice, and to reveal the possible mechanism of the aggravated atherosclerotic plaque vulnerability by emotional stimulation. METHODS Thirty 8-week-old male ApoE -/- mice were randomly divided into normal control group, high fat group, and emotional stimulation group. Ten 8-week-old inbred C57BL/6J mice served as blank control group. After 12 weeks of intervention, the serum levels of SDF-1 and CXCR4 were investigated by ELISA. The protein levels of SDF-1 and CXCR4 in platelets, aortas, hippocampus and bone marrow were determined by Western blot. The pathological damage of aortas was observed by oil red O staining. RESULTS Compared with blank control group, normal control group and high fat group, the mice subjected to emotional stimulation showed more serious atherosclerosis in aortas detected by oil red O staining, and increased levels of SDF-1 and CXCR4 in the plasma and aortas were also observed (P <0.05). The results of Western blot showed that the protein levels of SDF-1 and CXCR4 in platelets, aortas and hippocampus were increased in the mice subjected emotional stimulation, but the expression of SDF-1 and CXCR4 in the bone marrow was decreased (P <0.05). CONCLUSION Imbalance of SDF-1/CXCR4 may be the key target by which emotional stimulation accelerates the progression of atherosclerosis. 相似文献
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ZHANG Qiong WAN Chang-wu YU Yan-ni XIA-Bing LIU Jiang-jin ZHANG Qiao-jun LI Zhu WANG Cheng-fei DAI Jia-lin WANG Jie 《园艺学报》2021,36(12):2133-2138
AIM To explore the possible mechanism of cathepsin C (CTSC) and tumor necrosis factor-α (TNF-α) in coronary heart disease (CHD) by detecting the protein expression of CTSC and TNF-α in human coronary artery tissue. METHODS The coronary artery tissues from 52 cases of CHD and 25 cases of accidental death without any heart disease in the Forensic Judicial Expertise Center of Guizhou Medical University from October 2018 to December 2019 were collected as CHD group and control group, respectively. The coronary artery stenosis and intimal plaque formation were examined by histopathology, the protein expression of CTSC and TNF-α was determined by Western blot, and the intracellular expression of CTSC and TNF-α was analyzed by immunohistochemical staining. RESULTS The results of HE staining showed that the intima of coronary artery in control group was smooth, and no thickening or stenosis was observed. In CHD group, the intima thickened irregularly, atherosclerotic plaques formed, the intima became thinner and the lumen showed eccentric stenosis in varying degrees (P <0.05). The results of Western blot showed that the expression of CTSC and TNF-α in CHD group was significantly higher than that in control group (P <0.05). Immunohistochemical staining showed that both CTSC and TNF-α were expressed in the cytoplasm of foam cells, and their positive expression was significantly higher than that in control group (P <0.05). The results of Pearson moment correlation analysis showed that there was positive correlation between the expression of CTSC and TNF-α in CHD (r2 =0.743, P <0.05). CONCLUSION The up-regulated expression of CTSC in coronary artery tissue may promote the expression of TNF-α and affect the occurrence and development of CHD. 相似文献
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为评估入侵害虫红棕象甲Rhynchophorus ferrugineus对本土农林生态系统的风险,于2016—2019年采用受害植株调查和成虫诱捕的方法跟踪监测该虫在加拿利海枣Phoenix canariensis引种点及周边1 600 m半径范围内本土棕榈Trachycarpus fortune上的发生情况,并对来自野外加拿利海枣与棕榈上的成虫形态及繁殖力进行比较。结果显示,红棕象甲可随加拿利海枣引种定植而入侵当地生态系统,当其在加拿利海枣上暴发成灾后,还能转移到周边棕榈上继续为害,红棕象甲为害致死的棕榈植株数随着引种植物死亡数的增加而增加。野外加拿利海枣与棕榈上红棕象甲成虫的体重、体长以及按雌雄1∶1配对交配后的产卵量、孵化率相当,但棕榈种群雌虫的翅展较加拿利海枣种群明显变短,表明红棕象甲转移取食本土棕榈后可成功定殖、建立种群,且适合度并未降低。雌虫翅展变短可能与该入侵种表型可塑性有关,反映出其对棕榈的快速适应与进化,表现为"前适应"策略。考虑红棕象甲成虫飞行能力强,建议调高棕榈分布省份该虫的风险预警等级、调整防控策略,开展跟踪监测以了解入侵地实情。 相似文献