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61.
西双版纳勐海县境内南览河流域具有良好的天然植被,蝴蝶种类繁多。为了开展重要观赏蝶种的人工繁育试验,2013—2018年对南览河中低海拔地带的常见观赏蝴蝶及其野生寄主植物资源开展了进一步的深入调查,结果表明,经过5年定点调查和沿线观察,在区域内发现兼具较高观赏价值及人工繁育潜力的蝶种46个;通过观察野外成虫的产卵活动,结合野外套袋及室内饲养幼虫,发现蝴蝶寄主植物38种,初步查明了相关蝶种的野生寄主植物资源。调查工作可为筛选出当地适生优良寄主植物、进一步开展相关蝶种的人工养殖试验提供参考。 相似文献
62.
甲壳素对连作平邑甜茶生长、光合及抗氧化酶的影响 总被引:2,自引:0,他引:2
以苹果连作土盆栽的平邑甜茶幼苗为试材,探讨了0、0.5、1.0和2.5 g·kg-1不同施入量的甲壳素对其光合速率、活性氧含量及抗氧化酶活性的影响。结果表明,1.0 g·kg-1的甲壳素处理能显著促进幼苗株高、地径,干样质量和根冠比的增加,根冠比为对照的1.51倍;明显提高了幼苗叶片光合色素含量、净光合速率和蒸腾速率,其中光合速率为对照的1.30倍;同时提高了幼苗叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)活性,分别为对照的1.10倍、1.85倍、1.77倍和1.43倍;减少了叶片丙二醛(MDA)、过氧化氢(H2O2)和超氧阴离子的积累,分别为对照的73%、62%和34%,降低了脯氨酸(Pro)和可溶性糖含量。当甲壳素施用量为2.5 g·kg-1时则显著抑制平邑甜茶幼苗生长,降低幼苗叶片光合速率和抗氧化酶活性,并使超氧阴离子和脯氨酸含量明显上升。因此,适宜用量的甲壳素能减轻苹果的连作障碍。 相似文献
63.
Based on morphological, molecular biological, and molecular systematic studies, we describe here a new species of Malus from Yunnan, China. We compared the morphology of this new species, Malus shizongensis Liu sp. nov, with three Malus species, including M. hupehensis, M. baccata, and M. micromalus. Although the appearance of M. shizongensis was similar to these three species, it differed in height, branch color, branch hair, and flower color. To better identify the taxonomy of this new species, genome of M. shizongensis and that of seven Malus species, including M. prunifolia, M. sylvestris, M. sieversii, M. hupehensis, M. baccata, M. robusta, and M. micromalus were analyzed. A phylogenetic tree based on genome analysis indicated that M. shizongensis was close to M. hupehensis. Furthermore, M. shizongensis had its species-specific SNPs, and the number of species-specific SNPs was similar to that of three close species(M. hupehensis, M. baccata, and M. micromalus). Based on the above information, we named this new species as M. shizongensis Liu sp. nov. 相似文献
64.
ZHANG Han MA Jing ZHANG Yun-ling ZHANG Shu-ming XU Qing-rui WANG Wei-ming 《园艺学报》2015,31(12):2244-2248
AIM: To investigate whether Mycoplasma pneumoniae (Mp)-induced interleukin-1β (IL-1β) production in RAW264.7 cells is through the activation of NLRP3 inflammasome via reactive oxygen species (ROS). ME-THODS: RAW264.7 cells were randomly divided into 3 groups. In normal group, RAW264.7 cells were treated without Mp. In model group, RAW264.7 cells were treated with 1∶ 10 multiplicity of infection (MOI) of Mp. In NAC group, RAW264.7 cells were pretreated with N- acetylcysteine (NAC) at a concentration of 5 mmol/L for 30 min before infection with Mp. The RAW264.7cells were infected with Mp (1∶ 10 MOI) for 4, 8, 16 and 24 h in model group and NAC group, respectively. The intracellular ROS level was analyzed by flow cytometry. The mRNA expressions of NLRP3, ASC and caspase-1 were detected by real-time PCR. The protein levels of NLRP3, ASC and caspase-1 p20 were determined by Western blot. The levels of pro-inflammatory cytokine IL-1β in the supernatant were measured by ELISA. RESULTS: Compared with normal group, the production of ROS were significantly increased at 4, 8, 16 and 24 h after infection, the mRNA expression of NLRP3, ASC and caspase-1 were increased at 8, 16 and 24 h after infection, the protein levels of NLRP3, ASC and caspase-1 p20 were increased at 16 and 24 h after infection, and the releases of IL-1β were increased at 24 h after infection in model group (P<0.01). Compared with the model group, the level of ROS in NAC group decreased, so as the expression of NLRP3, ASC and caspase-1 at mRNA and protein levels and the releases of IL-1β in the supernatant at the corresponding time points. CONCLUSION: Mp may stimulate the ROS production to activate NLRP3 inflammasome in RAW264.7 cells. 相似文献
65.
66.
为了了解抚育间伐对燕山北部山区山杨林物种多样性的影响,对山杨林抚育间伐前后的物种多样性进行了调查和分析,结果表明:抚育后林地草本植物的物种多样性高于未抚育林地,抚育间伐林地草本植物的Patrick指数、Margarlef指数、Simpson指数和Shannon-Wiener指数分别为35.0、6.13、0.89和2.76,未抚育样地分别为29.0、4.90、0.32和1.91;抚育林地灌木的Patrick指数、Margarlef指数、Simpson指数和Shannon-Wiener指数分别为9.0、1.41、0.43和0.98,未抚育林地则分别为8.0、1.48、0.68和1.51,除Patrick指数外,抚育林地的其他多样性指数都低于未抚育林地;抚育间伐使乔木层优势种的优势更为明显。由此得出结论,抚育间伐对山杨林的物种多样性有明显影响,但草本、灌木与乔木对抚育间伐的响应有所不同。 相似文献
67.
Iosif Vasiu Roman Dąbrowski Asta Tvarijonaviciute 《Reproduction in domestic animals》2021,56(2):208-230
Mastitis is a common reproductive disorder in bitches, reaching a prevalence of 0.71%. Mastitis has a wide range of forms, from asymptomatic to severe gangrenous mastitis that can lead to septic shock and death of the bitch and nurslings. However, most of the time it is overlooked, undiagnosed or mistreated. The present systematic review was performed to revise and summarize the existing knowledge related to this disorder, including diagnosis, treatment and prevention. 相似文献
68.
Patrick M. Ko
ovský 《Ecology of Freshwater Fish》2019,28(1):33-40
Silver chub (Macrhybopsis storeriana, Kirtland, 1844) is a native Cyprinid in Lake Erie, one of the Laurentian Great Lakes of North America. It is listed as endangered by the US state of New York and Canada, which has a recovery plan, and as special concern by the state of Michigan. Silver chub faces a potential threat to recovery from control efforts for invasive Grass carp (Ctenopharyngodon idella, Valenciennes 1844). Among the knowledge gaps for protection and restoration is current diet data. I describe the diet of silver chub from western Lake Erie in 2014, and I compare it to past studies to assess changes in diet through time. Silver chub captured in bottom trawls May–September 2014 were frozen in the field, and stomach contents were preserved in ethanol. Diet taxa were identified to the lowest practical taxonomic unit, then dried and weighed. Frequency of occurrence in silver chub diets was highest for Hexagenia spp. mayflies (79%). Dreissena spp. and Hexagenia spp. were both 41% of the diet by dry weight. Analysis of δ13C isotopes identified Hexagenia spp. as the primary source of carbon in silver chub. Compared to past studies, Dreissena spp. have mostly replaced Sphaeriidae and Gastropoda in silver chub diets. There also have been seasonal shifts in relative amounts of shelled organisms and Hexagenia spp. This study and past research suggest a functional link between silver chub and Hexagenia spp. abundance. Maintenance and recovery of silver chub may be dependent on maintaining Hexagenia spp. populations. 相似文献
69.
福建省新分布植物记录 总被引:2,自引:0,他引:2
在第4次全国中药资源普查福建省建宁县试点县野外调查中陆续发现多个福建省地理新分布记录种,经整理鉴定,继续报道4个新分布记录种:日本金腰[Chrysosplenium japonicum(Maxim.)Makino]、赶山鞭(Hypericum attenuatum Choisy)、异堇叶碎米荠(变种)(Cardamine violifolia O.E.Schulz var.diversifolia O.E.Schulz)和杜鹃兰[Cremastra appendiculata(D.Don)Makino]。 相似文献
70.
运用矩阵分析方法,讨论了非奇异H-矩阵的判定问题,得到两个非奇异H-矩阵新的判定准则,并以数值例子说明判定方法的有效性. 相似文献