皂质芦荟的组织培养

将皂质芦荟的茎段及幼苗作为外植体进行组织培养,试验结果表明：皂质芦荟的茎段经40d左右可诱导形成愈伤组织,再经20d萌生再生芽：幼苗培养需要30d左右基部直接分化再生芽。同时经试验筛选出愈伤组织形成、再生芽分化和生根的最适培养基为：MS＋6－BA 2.0mg/L NAA 0.1mg/L、MS 6-BA 3.0mg/L NAA 0.1mg/L和MS NAA 0.3mg/L。     

香叶天竺葵快速繁殖的研究

以柠檬香的皱波天竺葵 (Pelargoniucrispum)的叶片和茎段为外植体进行试管培养 ,结果叶片和茎段可诱导形成愈伤组织。经试验筛选结果为 :培养基MS BA 0 .75mg L NAA 0 .2 0mg L最适于愈伤组织的诱导 ,也适于不定芽分化和从生芽的分化增殖 ;培养基 1 2MS NAA 0 .3mg L IAA 0 .1mg L为根系诱导及生长的最佳配方 ,生根率达 1 0 0 %。     

蔊菜和珍珠露水草的组织培养

植物名称:蔊菜(Rorippa montana)珍珠露水草(Cyanotis arachnoidea)。材料类别:蔊菜茎段及珍珠露水草叶鞘。培养条件:基本培养基为MS。诱导愈伤组织和芽的培养基附加(1)NAA1mg/l(下同),2,4-D0.1,BA0.5;(2)NAA0.2,BA2;(3)NAA0.05,BA1。诱导生根培养基为1/2MS附加NAA0.1。培养温度25—28℃,每天光照12小时,光照度1500—2000lx。生长与分化情况:蔊菜茎经消毒后切成长约0.5cm的茎段,接种到培养基(1)上进行暗培养。外植体产生明显的肿胀状愈伤组织,并发生开裂,     

三叶香茶菜的组织培养及植株再生

1植物名称三叶香茶菜[Rabdosia ternifolia（D．Don）Hara]。 2材料类别带腋芽茎段。 3培养条件（1）诱导愈伤组织的培养基：MS＋6．BA2mg.L^-1（单位下同）＋NAA0．5;（2）芽分化及继代培养基：MS＋6．BA2＋IBA0．5：（3）诱导生根培养基：1／2MS＋IBA0．5＋NAA0．1。     

孔雀花的组织培养和快速繁殖

植物名称:孔雀花(Aster ericoidus)。材料类别;茎尖、带腋芽茎段。培养条件:以MS为基本培养基:附加不同激素。诱导分化培养基:(1)MS BA1.0mg/L(单位下同) NAA0.1;(2)MS BA1.0。增殖培养基:(3)MS BA0.5 NAA0.2;(4)MS BA1.0。生根培养基:(5)MS_0(不加生长激素)。培养温度25±2℃;每天光照12小时,光照度1000～2000lx。生长与分化情况:     

樱桃砧木Colt离体叶片再生

以樱桃砧木Colt试管苗的叶片为外植体 ,通过先诱导愈伤组织分化不定芽以及叶片直接分化不定芽两种途径诱导再生。结果表明 :在MS附加NAA 1 0mg/L、KT3 0mg/L、ZT0 2 5mg/L培养基中 ,愈伤诱导率可达 1 0 0 % ;诱导的愈伤在MS附加NAA 0 2mg/L、IAA0 5mg/L、6 BA 0 5mg/L、KT 1 0mg/L、GA 0 5mg/L培养基中 ,不定芽分化率为 2 1 3% ;在MS附加 6 BA 6 0mg/L、NAA 1 0mg/L、GA 0 5mg/L中 ,叶片 -叶柄不定芽诱导率可达 48 3%。     

地黄组织培养及植株再生的研究

以地黄根茎所获无菌苗为材料,对其愈伤组织诱导、分化和再生植株的获取进行了初步研究。结果表明：取叶片、茎段、叶柄进行愈伤组织诱导,筛选出最适培养基为MS附加2,4-D0．5mg／L、BA1．0mg／L,愈伤组织诱导率可达100％。将叶片接种在分化培养基中,诱导不定芽,其最适分化培养基为MS附加BA 3mg／L、NAA 0．1mg／L,分化率为77．5％。试管苗在改良的MS(大量与微量元素、铁盐和有机物质各1／2)附加NAA 0．05mg／L的培养基上,经过15～20d培养,生根率可达100％。     

叶子花的组织培养与微繁技术研究

叶子花茎尖、茎段接种在MS附加不同浓度组合的6-BA、IAA、IBA、NAA培养基上可诱导茎尖及腋芽的生长而获得无性系芽,无性系芽茎尖和茎段在MS附加6-BA0．5mg／L,NAA0．05mg／L进行继代培养,一般不形成丛生芽,以茎尖生长和腋芽萌生增殖,增殖系数为2．73;高度大于3cm的增殖芽在1／2 MS附加IAA lmg／L、IBA lmg／L、NAA0．2mg／L培养基上生根率为80．5％,生根苗用“二步法”移栽成活率在97％以上。无性系芽的幼叶、茎段在MS附加6-BA和NAA、2,4-D培养基上能高频产生愈伤组织,但愈伤组织在所试验的所有培养基上均无不定芽或胚状体的分化。     

芦荟的组织培养

植物名称:芦荟(Aloe),品种为中国芦荟(Aloe vera var.chinensis)美国芦荟(Aloe americanum)。材料类别:茎尖和带1～2个腋芽的嫩茎切段。培养条件:以MS为基本培养基。诱导分化与生长培养基为MS+BA2.0mg/L(单位下同)+NAA0.2;生根培养基为1/2MS+NAA0.05～0.1。     

大果良种沙棘愈伤组织诱导及植株再生的研究

大果良种沙棘的幼嫩茎尖,茎段外植体接种在MS,1／2MS附加不同浓度配比的IAA,IBA,BA,NAA培养基上可诱导茎尖及腋芽生长,将诱导产生的无性系芽接种在MS或1／2MS附加BA0．3－0．5mg/L,NAA0．05mg/L的培养基上可形成丛生芽,同时在小叶片和嫩茎上诱导产生愈伤组织,继续培养愈伤组织表面形成大量的绿色突起,进一步分化成不定芽,在相同培养基上,不定芽上可直接产生不定芽,从而形成多达数百个的不定芽族,不定芽长至3cm时切下转至1／2MS附加IAA或IBA 0．2mg/L的培养基上可生根而形成完整 的再生植株。     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.     

杆状病毒出芽病毒粒子膜融合蛋白的研究进展

杆状病毒是一类感染节肢动物的病原微生物,其基因组为双链环状DNA,大小为80～180kb.     

Inception of the Modern Public Health System in China and Perspectives for Effective Control of Emerging Infectious Diseases: In Commemoration of the 140th Anniversary of the Birth of the Plague Fighter Dr. Wu Lien-Teh

In this article, we systematically review Dr. Wu Lien-Teh's academic achievements and outstanding contributions in the prevention and control of the plague epidemic in northeast China and introduce the development of the earliest public health epidemic prevention system in China in order to commemorate the 140th anniversary of Dr. Wu Lien-Teh's birth. We hope that this article will provide insights into the effective prevention and control of emerging infectious diseases as well as the current worldwide pandemic of COVID-19, facilitating the improvement and development of public health systems in China and around the globe.