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11.
槟榔(Areca catechu L.)的民族植物学 总被引:3,自引:0,他引:3
本文从民族植物学的观点介绍了我国南方各省嚼槟榔的习俗、历史及演变,分析了这个习俗的形成原因及槟榔的药用价值。作者认为咀嚼槟榔有成瘾性,但是否对人的中枢神经系统有损害,必须进一步研究。作者对这种习俗提出了几点看法和建议,对槟榔的开发利用有重要参考价值。 相似文献
12.
用快中子照射红粒济宁3号小麦干种子,后代获得白粒植株,经选育而成白粒济宁3号。白粒济宁3号与红粒济宁3号比,除籽粒颜色差别外,籽粒蛋白含量显著高于红粒济宁3号,而落黄性、籽粒饱满度、千粒重、产量均略低于红粒济宁3号,该品种累计种植面积10余万亩。 相似文献
13.
14.
Xiong Zhang Ming-You Peng En-Ming Feng Qing-Dan Li Lu Chen Hu-Cheng Yang Bing Guo Hong Liang Ying-Tong Di Lei Tang Ying Yan 《化学与生物多样性》2023,20(10):e202301061
Three previously undescribed diterpenoids, helioscopnoids A–C, and eight known compounds were isolated from the whole plants of Euphorbia helioscopia. Their structures were established by extensive analysis of spectra and data comparison with previous literatures. Among them, compound 4 was identified as 24,24-dimethoxy-25,26,27-trinoreuphan-3β-ol with revised configurations of C-13, C-14, and C-17 (13R*, 14R*, 17R*). Cytotoxicity assays revealed that all compounds exhibited varying levels of cytotoxicity against H1975 cells, with compound 9 displaying the most potent activity, as indicated by cell viability rates of 18.13 % and 20.76 % at concentrations of 20 μM and 5 μM, respectively. This study expands the understanding of E. helioscopia terpenoids’ structural diversity and biological activities, contributing to the exploration of potential therapeutic applications. 相似文献
15.
Shumin Guo Jie Wu Zhaoqiang Han Zhutao Li Pinshang Xu Shuwei Liu Jinyang Wang Jianwen Zou 《Global Change Biology Bioenergy》2023,15(4):478-493
Existing studies suggest that biochar application can reduce soil nitrous oxide (N2O) emissions, mainly based on short-term results. However, it remains unclear what the effects (i.e., legacy effects) and underlying mechanisms are on N2O emissions after many years of a single application of biochar. Here, we collected intact soil columns from plots without and with biochar application in a subtropical tea plantation 7 years ago for an incubation experiment. We used the N2O isotopocule analysis combined with ammonia oxidizer-specific inhibitors and molecular biology approaches to investigate how the legacy effect of biochar affected soil N2O emissions. Results showed that the soil in the presence of biochar had lower N2O emissions than the control albeit statistically insignificant. The legacy effect of biochar in decreasing N2O emissions may be attributed to the reduced effectiveness of the soil substrate, nitrification and denitrification activities, and the promotion of the further reduction of N2O. The legacy effect of biochar reduced the relative contribution of nitrifier denitrification/bacterial denitrification, nitrification-related N2O production, and the relative abundance of several microorganisms involved in the nitrogen cycle. Our global meta-analysis also showed that the reduction of N2O by biochar increased with increasing application rate but diminished and possibly even reversed with increasing experimental time. In conclusion, our findings suggest that the abatement capacity of biochar on soil N2O emissions may weaken over time after biochar application, but this remains under further investigation. 相似文献
16.
DISCOVERY OF VERTEBRATE FOSSILS AND PALEOLITHIC ARTIFACTS IN DANJIANG SUBMERGING AREA AND ITS IMPLICATIONS 总被引:1,自引:1,他引:0
IntheareatobefloodedinthesecondengineeringstagefortheDanjiangreservoir,wediscovered16vertebratefossillocalitiesand52Paleolithicsitesin1994,andcollected603artifactsandmanyfossils.Ofthel6new1yfoundvertebratefossillocalities,threearereptilesitesrepresentedbydinosaureggsandlimbbones,andl3producemamma1s,including4Pale0gene,2Ne0geneand7Quaternarysites'ThemammalianlocalitiesareofPale0cene,Eocene,EarlyMiocene,andPli0ceneorEarlyPleistocene,MiddleandIntePleistocene,respectively.Theyfillinsomestrat… 相似文献
17.
Diuron treatment for weed control greatly increased anthurium root rot caused by Pythium splendens, P. spinosum, P. vexans and Calonectria crotalariac. Diuron in agar medium was inhibitory to the growth of mycelium, formation and germination of sporangia of P. splendens. Sporangia of P. splendens produced in diuron-amended medium did not differ in pathogenecity to anthurium roots from those produced in diuron-free medium. When diuron was applied to kill weeds in the planting medium, the population of P. splendens in it was not decreased during the test. Diuron was inhibitory to a number of micro-organisms in the platiting medium. Exudation of anthursum roots was not increased by diuron treatment. Increase in severity of anthurium root rot by diuron treatment was similar whether the experiments were performed in the presence or absence of planting medium, suggesting that the enhancing effect of diuron on root rot is mainly due to an increase in susceptibility of the host plants. 相似文献
18.
小麦返白系与不同基因型小麦品种杂交后代IPO表达的研究 总被引:3,自引:1,他引:2
以小麦返白系和对照矮变1号以及返白系与各不同生态类型的冬性、半冬性、春性小麦的杂交、回交F1、F2代为材料,研究这些不同基因型品种在返白期间过氧化物酶同工酶(IPO)基因表达模式的动态变化特点。结果表明,在返白期间以返白系为母本的各杂交、回交品种的白化苗中,IPO的个别酶分子表现了可逆的基因阻遏和去阻遏的表达现象。这种表达特点在正、反杂交后F1代中表现一致,从遗传模式上分别属于质-核互作型的分子遗 相似文献
19.
RFLP tagging of a salt tolerance gene in rice 总被引:10,自引:0,他引:10
A salt tolerant rice mutant (M-20) was obtained through selection in vitro. Its tolerance was stably inherited over eight generations and most traints between M-20 and its sensitive original 77–170 (Oryza sativa) were very similar. By deriving an F2 population of M-20 × 77–170 and splitting every F2 individual into two parts, with one part planted in normal conditions and another part in saline conditions, the inheritance of salt tolerance in rice was studied. Under normal conditions, there was no apparent segregation among F2 individuals. Under saline conditions, however, the segregation of traits was obvious. According to our standards, the ratio of salt sensitive:moderately-tolerant:tolerant plants was 25:42:18, in accordance with a 1:2:1 ratio. It suggested that the improvement of salt tolerance in our materials was induced by the mutation of a major tolerant gene which showed incomplete dominance. By use of 130 RFLP probes distributed throughout the rice genome, the gene was tagged by a single copy DNA probe, RG4, which was located on chromosome 7. The genetic distance between the salt tolerant gene and RG4 was 7.0 ± 2.9 cM. Based on the split method, a method which could be currently used to evaluate the damage of salt stress in rice was proposed. 相似文献
20.
应用标志-释放-回收技术研究小皱蝽成虫的主要种群特征,结果如下:(1)成虫扩散的偏离度Ku=2.4,为一阶峻开曲线;(2)分别用Peterson和Jackson方法对种群蜜度进行了估计,结果表明,Jackson的方法较好;(3)雄虫平均寿命40-45,虫平均寿命120-130。天。 相似文献