甘薯近缘野生种Ipomoea Littoralis全基因组Survey分析

Ipomoea littoralis是甘薯的近缘野生种之一,对其全基因组的研究可为甘薯种质资源的创新提供参考,同时为全基因组精细图谱的绘制打下基础。本研究通过二代高通量测序技术（Illumina Hiseq 2500）,测序深度约为60×,经过滤后得到22.45 G数据,结合生物信息学手段估算基因组大小、杂合率、重复序列和GC含量等基因组特征。预估基因组大小经修正后为676.27 Mb。K-mer分析结果得出I. littoralis基因组中重复序列所占比率为60.98%,杂合率为0.81%;初步组装结果,contigs N50为0.684 kb,总读长为0.538 Gb,scaffolds N50为12.09 kb,总读长为0.602 Gb;GC平均深度及含量分布出现分层现象。本研究首次报道I. littoralis的基因组特征信息,为进一步全基因组深度测序提供参考。     

9份叶菜型甘薯种质在海南试种报告

报道了9份叶菜型甘薯种质在海南的试种结果。根据甘薯嫩茎叶食味的综合品尝评价,兼顾鲜嫩茎叶的产量及适应性,认为海南种植广薯菜1号和2号最为理想。同时,推荐继续试种福薯7-6和枝菜薯。     

紫红薯色素提取工艺的比较

[目的]选用2种提取工艺并进行比较,以期能获得在生产实践中的应用。[方法]利用水溶水浸提取工艺和酒精水溶液提取工艺对紫红薯色素的提取进行研究与比较。[结果]结果表明:采用水浸水溶提取工艺的样品色价为2~5,而采用酒精水溶液提取工艺的样品色价为10。[结论]酒精水溶液提取工艺明显有利于紫红薯色素的提取。     

污水浓度对水培净化系统净化效果的影响

在植物水培污水净化系统中对污水浓度与氮磷净化效果间的关系进行研究,蕹菜作为水培植物材料,对设置5%、10%、20%不同浓度的化粪池出口污水,分别于第0、2、4、6、8、11 d测定TN、NH4+-N、过滤后总氮(fTN)、总磷(TP)、PO43-P、过滤后总磷(fTP)、CODCr、过滤后COD(fCODCr).结果表明,TN、TP的去除率随污水浓度升高而升高,水培液中TN、TP浓度随污水浓度升高而降低.适当提高污水浓度有利于提高污水中TN、TP的去除效率.尽管蕹菜对污水中化学需氧量(COD)的去除没有影响,适当提高污水浓度也有利于提高COD去除率.污水浓度对铵态氮、磷酸根的去除影响不明显.     

化学药剂处理对蕹菜种子发芽的影响

采用培养皿发芽法,研究了化学药剂处理对蕹菜种子发芽的影响。结果表明,GA3 Ca2 混合液处理蕹菜种子,对促进种子发芽和提高种子活力表现加成作用,以50 g/L GA3 5mmol/L Ca2 处理较为适宜。蕹菜种子经稀盐酸预处理1 h后,以100 mg/L GA3浸种处理,可明显提高种子发芽势和活力指数,促进种子发芽。用30~50 mmol/L的低浓度NaCl胁迫处理蕹菜种子,能提高种子发芽率,但随着NaCl胁迫浓度的增大,对发芽抑制作用明显增强。低浓度(0.05%~0.07%)ZnSO4浸种可促进种子发芽,高浓度(>0.09%)则抑制种子发芽。     

甘薯肌醇-1-磷酸合成酶基因的克隆及序列分析

甘薯(Ipomoea batatas (L.) Lam.)新品系农大603是从感茎线虫(Ditylenchus destructor)病品种徐薯18的辐照后代中获得的一个抗茎线虫病的突变体。以农大603和徐薯18块根的mRNA为模板，根据植物抗线虫病基因NBS保守氨基酸序列设计引物，进行 RT-PCR分析，发现农大603的肌醇-1-磷酸合成酶(Myo inositol-1-phosphate synthase , MIPS)基因的表达量高于徐薯18。采用3'RACE技术扩增出MIPS基因的3'末端cDNA。根据植物MIPS基因 5'端一段保守的氨基酸序列设计兼并引物，并与3'端的特异引物组合，扩增出该基因的5'端cDNA序列。DNA序列比对表明，甘薯MIPS基因与大豆(Glycine max)、番茄(Lycopersicon esculentum )的MIPS基因同源性较高，分别达83.63 %和83.89 %。甘薯MIPS基因全长cDNA的克隆，有利于进一步研究该基因与抗甘薯茎线虫病的关系。     

表达bar基因的抗除草剂转基因甘薯的获得

用农杆菌介导法将bar基因导入甘薯主栽品种徐薯18的胚性悬浮细胞中,获得了抗除草剂的转基因植株.农杆菌菌株EHA105携带的双元载体pCAMBIA3300上含有bar基因.来自于徐薯18胚性悬浮细胞的直径为0.7～1.3 min的280个胚性细胞团用于遗传转化.共培养3 d后,首先在含有2 mg/L 2,4-D、100 mg/L Carb的液体MS培养基中培养1周,然后将胚性细胞团转移到添加2 mg/L 2,4-D、100 mg/L Carb 和0.3 mg/L PPT的固体MS培养基上进行选择培养.选择8周后,将获得的37个PPT抗性愈伤组织转移到添加1 mg/L ABA、100mg/L carb和0.3 mg/L PPT的固体MS培养基上,其中的34个愈伤组织诱导得到体细胞胚并发芽形成小植株,共获得了164株拟转基因植株.PCR分析表明,其中的123株为转基因植株.Southern blot和Northern blot分析表明,bar基因稳定整合到转基因植株的基因组中并正确表达.除草剂喷洒试验结果表明,转基因植株具有高度除草剂抗性.     

甘薯（Ipomoea batatas (L.) Lam.）及其近缘野生种原生质体的植株再生

对甘薯品种高系14号及其近缘野生种I.triloba L、和I.lacunosa L,进行原生质体植株再生研究。从离体培养植株的叶柄分离出原生质体,将其培养在含有0.05mg/L 2,4-D和0.5mg/L激动素(KT)的MS培养基中,从原生质体获得了高频率的愈伤组织。培养8-12周后,将直径达2—3mm的小愈伤组织转移到添加0.05mg/L 2,4-D的MS培养基上。转移3-6周后,将愈伤组织进一步转移到添加吲哚乙酸(IAA)和6-苄基嘌呤(BAP)的MS培养基上,一些愈伤组织再生出植株。未再生植株的愈伤组织进一步在MS基本培养基上培养,它们也再生出植株。本研究从I.triloba原生质体获得高频率的植株再生;首次从I.lacunosa原生质体再生出植株;从高系14号原生质体也再生出完整植株。     

Regression analysis of genotype x environment interaction in sweet potato

Summary Two experiments, each involving a set of 10 sweet potato clones, were conducted for three years at 4 sites (Ekona, Ebolowa, Nkolbisson, and Bambui Plain) in Cameroon. Data obtained were subjected to analysis of variance to determine the presence of genotype x environment (G x E) interactions, and to regression analysis to assess the performance of clones across anvironments. Environments were assessed in two ways: (i) the mean response of all clones (dependent assessment), and (ii) the average performance of a different set of clones (independent assessment).The first experiment (Expt 1) produced higher yields but had fewer stable clones than the second (Expt 2).The analysis of variance revealed that the clones interacted significantly with environments for all traits.The study has identified high yielding and stable sweet potato clones for distribution to growers in the major areas of cultivation in the tountry. Despite slight differences in numbers of clones judged stable by the various regression indices in the two methods of environmental assessments, the rankings of clones on the basis of their linear regression coefficients were similar. In a developing country like Cameroon, with limited resources and where sophisticated equipment for obtaining physical or biological measures of the environment may be lacking, the mean performance of genotypes may still be the most reliable measure of environment in evaluating the stability of performance of crop cultivars.     

Overcoming self-incompatibility in Ipomoea cairica by IAA

Summary Ipomoea cairica Sweet (Convolvulaceae) exhibits sporophytic self-incompatibility. This has partially been overcome under in vitro conditions, by treating the pollen and/or stigma with 10^-5–10^-1M indole-3-acetic acid (IAA), the optimum being 10^-2M. The self-pollen. which otherwise does not even stick to stigma. germinates after self-pollination provided only one or both the partners are treated. The pollen tubes not only penetrate stigmatic papillae but also traverse the whole length of the style, at least in optimum experimental combinations.