金银花扦插繁殖技术研究

以四倍体金银花1～2 a生木质化枝条为试材,研究插穗蘸取根宝2号+遮阳网,插穗蘸取根宝2号、无遮阳网,仅有遮阳网,既无遮阳网、也没蘸取根宝2号4种条件对金银花扦插效果的影响。结果表明,插穗在蘸取根宝2号并有遮阳网的条件下,扦插效果最好,既无根宝2号、又没遮阳网的扦插效果最差。     

罗非鱼染色体组操作研究现状与展望

罗非鱼属鲈形目(Perciformes),丽鱼科(Cichlidae),约有700种,主要分布于非洲。按照Trewavas[1]分类法,可把罗非鱼分为3个属,即Tilapia属、Sarotherodon属和Oreochromis属。目前,有生产应用价值的主要是Oreochromis属的尼罗罗非鱼(O.niloticus)、奥利亚罗非鱼(O.aureus)以及莫桑比克罗非鱼(O.mossambicus)[2]。罗非鱼具有生长快、食性杂、繁殖快、产量高和味道鲜美而少刺等优良特征,近年来,全球罗非鱼养殖产量逐年递增,现已成为世界性主要养殖鱼类之一。这就迫使人们不断对养殖罗非鱼进行遗传改良,以防其种质退化。当前,国内外除了人工选…     

除草剂Oryzalin诱变西瓜四倍体及倍性鉴定

 以两个二倍体西瓜自交系为实验材料,研究除草剂Oryzalin不同滴苗浓度（30,40,50,60mg/L）和不同处理时间（1,2,4,6d）对西瓜四倍体的诱变效果,同时进行变异植株的外部形态和气孔观察及染色体鉴定。结果表明：以50mg/L浓度,2d滴苗处理诱变效果最佳,两个材料四倍体诱变率分别达到1563%和1719%。其变异植株通过染色体计数法鉴定得出染色体数为44,确定为四倍体植株,植株表现为叶片钝圆而厚,叶色深绿,叶缘多锯齿,花瓣颜色深黄,花瓣增宽、增厚;叶片气孔密度明显减小,保卫细胞体积增大。Oryzalin对不同基因型的四倍体诱变效果具有一定差异。     

小鼠电融合胚胎发育影响因素的研究

电融合技术，是获得四倍体胚胎的主要手段．本试验研究了各种不同因素，对小鼠电融合胚发育的影响．结果表明，电刺激前后，使用不同的操作液对融合胚发育有影响．电刺激前使用Ｍ２液、电刺激后在Ｗｈｉｔｔｅｎ氏液中融合，然后转入ＣＺＢ液中培养，这一操作体系（Ｍ／Ｗ—ＣＺＢ）效果最好，融合胚的囊胚发育率为８０．５％，显著高于Ｍ／Ｗ—Ｗ，Ｗ／Ｗ—Ｗ，Ｗ／Ｗ—ＣＺＢ组，后者的囊胚发育率分别为０，０，５４．５％（Ｐ＜０．０５）．试验还发现，刺激强度为１．０ｋｖ／ｃｍ，８０μｓ；１．０ｋｖ／ｃｍ．４０μｓ和０．８ｋｙ／ｃｍ，８０μｓ时，融合囊胚的发育率分别为７９．０，８１．９和７１．１％．ＨＣＧ注射后４７ｈ、４８ｈ的２—细胞胚胎的融合胚发育率，显著高于（Ｐ＜０．０１）ＨＣＧ注射后４２ｈ、４４ｈ和４６ｈ的，囊胚发育率分别为８２．９，８０．６，０，０和２２．８％．     

同源四倍体泡桐体外植株再生系统建立

以叶片为外植体,建立了同源四倍体兰考泡桐和白花泡桐体外植株再生系统.结果表明,同源四倍体兰考泡桐和白花泡桐幼苗叶片愈伤组织诱导的最适培养基分别为MS NAA 0.3 mg.L-1 BA 8 mg.L-1和MS NAA 0.1 mg.L-1 BA 10 mg.L-1;愈伤组织芽诱导的最适培养基分别为MS NAA 0.7 mg.L-1 BA 14mg.L-1和MS NAA 0.1 mg.L-1 BA 12 mg.L-1;幼芽生根的最适培养基皆为1/2 MS.     

Primary studies on tissue culture from mature embryos in diploid and tetraploid wheat

Using mature embryos (MEs) as the explants, the callus induction, embryogenic callus differentiation, plantlet regeneration and culture efficiency in diploid and tetraploid wheat of four genotypes were studied. The tested four genotypes wheat included cultivable emmer wheat (Triticum dicoccum Schuble), durum wheat (Triticum durum Desf.) and the common wheat progenitors Triticum dicoccoides and Triticum aegilopides. Results indicated that there were significant differences in the efficiency of callus induction, callus differentiation and plant regeneration among the tested genotypes. The efficiency of differentiation and regeneration shows strong genotype dependence. The rates of callus induction, embryogenic callus differentiation, plantlet regeneration and culture efficiency respectively were 95.00%, 90.00%, 32.40%, and 27.70% in cultivable emmer wheat, which were significantly higher than other tested genotypes. Therefore, this study has provided a basis for genetic transformation, gene cloning and molecular plant breeding in wheat and other related species. __________ Translated from Molecular Plant Breeding, 2007, 5(4): 480–484 [译自: 分子植物育种]     

Primary Study on Experiment of Tetraploid Induction in Haliotis discus hannai with PEG

The experiment was performed on induction tetraploid of Haliotis discus hannai at two-cell stage through cell fusion with PEG treatment. In this paper, the orthogonal experiment of three factors and three levels [L9 (34)] was used. Three factors and three levels were molecular weight of PEG: 8 000, 6 000, 4 000 mol·g-1; PEG concentration: 45%, 50%, 55%; treatment duration time: 1, 2, 3 min, respectively. The results showed that the optimal pattern of three factors and three levels on inducing tetraploid of Haliotis discus hannai at two-cell stage through using PEG treatment were: molecular weight 4 000, concentration 55%, treatment duration time: 2 min. The highest tetraploid induction rate was 10.8% at embryo period. The three factors treatment sequence was treatment duration time→concentration→molecular weight.     

Harvest management based on leaf stage of a tetraploid vs. a diploid cultivar of annual ryegrass

Leaf stage‐dependent defoliation is linked to the plant's physiological status and may be a more suitable criterion than time‐based intervals for harvesting forage grasses, but no reports of research with annual ryegrass (Lolium multiflorum Lam. var. westerwoldicum) were found. To address this, a 2‐year field study was carried out at Raymond, MS, on a Loring silt loam soil (fine‐silty, mixed, thermic Typic Fragiudalfs). Forage production, morphological characteristics and nutritive value responses to defoliation based on leaf stage (2, 3 and 4 leaves per tiller) and two residual stubble heights (RSH; 5 and 10 cm) of a tetraploid (“Maximus”) vs. a diploid (“Marshall”) cultivar of annual ryegrass were quantified. Forage harvested, in 2011, increased linearly as leaf stage increased from 7.3 to 8.8 Mg/ha, but during 2012 was least (7.0 Mg/ha) at 3‐leaf stage and similar at the other two leaf stages (7.6 Mg/ha). Tiller density was less for Maximus (1,191 tillers/m²) than for Marshall (1,383 tillers/m²). Leaf blade proportion decreased with increasing leaf stage and was greater by 9% for Maximus than for Marshall. Generally, forage nutritive value became less desirable with increasing leaf stage. There was a dichotomy in forage harvested and nutritive value responses, but maximum forage productivity was achieved when annual ryegrass was defoliated at the 4‐leaf stage interval.     

马铃薯栽培种色素遗传研究进展

分别对近一个世纪以来二倍体马铃薯栽培种(2n=2x=24)和四倍体马铃薯栽培种(2n=4x=48)的色素遗传研究进行了归纳和总结,比较分析了Salaman遗传模型和Dodds遗传模型的异同,认为色素在二倍体和四倍体栽培种中的遗传位点是相同的,以Dodds的二倍体遗传理论为基础发展和完善后的色素遗传模型可以解释色素在二倍体和四倍体栽培种中的遗传现象。