水蕹菜植生型混凝土对克氏原螯虾养殖污水除磷效果的研究

[目的]为克氏原螯虾的健康养殖提供可借鉴的基础参数。[方法]共设8组处理,对克氏原螯虾养殖污水进行25d净化处理．定期检测各处理组水体中的总磷含量（TP）。[结果]水蕹菜植生型混凝土（处理）对水体TP去除效果显著大于单纯的混凝土或水蕹菜,并呈现出一定的时间和生物量效应;通过统计分析拟合出TP、水蕹菜初始生物量密度（D）和处理时间（t）的二元函数模型。[结论]水蕹莱植生型混凝土对水体TP去除效果的函数模型可以为实践提供理论参数,     

美国紫薯试管苗微型繁殖的研究

为满足人们对经过热处理的美国紫薯试管苗种苗的大量需求,以微型嫩茎段为材料,采用组织培养和微型扦插的方法,进行了试管苗微型繁殖的研究。结果表明：在1/2MS＋IAA0．2 mg?L‐1＋蔗糖15 g?L‐1培养基上,以具有2个生长点和2个叶片的微型茎段繁殖试管苗,1株试管苗每年能繁殖200多万株试管苗;以具有2个生长点和2个叶片的苗微型茎段扦插到苗床上,其繁殖速度提高了1．8倍。定植的微型扦插试管苗生长较旺盛,美国紫薯的产量提高48．9％。     

甘薯(Ipomoea batatas(L.) Lam.)试管苗种质保存技术研究进展

甘薯种质资源的大田种植保存面临着严重的病毒感染以及病虫害、自然灾害的影响.由茎尖分生组织培养成无病毒苗并进行试管保存,是当前既经济又实用的方法.     

水培蕹菜使用吡唑醚菌酯的水生生态系统风险评估

为研究水培蕹菜使用吡唑醚菌酯对水生生物的潜在影响,在水培蕹菜白锈病发病初期,喷施25%吡唑醚菌酯悬浮剂和9%吡唑醚菌酯微囊悬浮剂,测定水培蕹菜和水体中的吡唑醚菌酯残留量,并结合毒理学数据评估其对水生生态系统的暴露风险。结果表明：吡唑醚菌酯在水培蕹菜和水中降解较快。悬浮剂和微囊悬浮剂在植株中的消解半衰期分别为2.9 d和3.9 d,微囊悬浮剂较悬浮剂在植株上的持效期更长。两种剂型在水中的消散半衰期都小于2 d,微囊悬浮剂在水中的有效浓度小于悬浮剂。基于暴露浓度峰值和时间加权平均浓度进行风险评估,悬浮剂对水生脊椎动物和无脊椎动物的急性和慢性风险商值,及其对初级生产者的慢性风险商值均大于1;微囊悬浮剂对每一类水生生物的风险商值都小于悬浮剂,但其对水生生物的急性暴露风险同样不可接受（风险商值仍大于1）,慢性风险商值仅在基于时间加权平均浓度计算时小于1。研究表明,吡唑醚菌酯在水培蕹菜上使用对水生生态系统的风险不容忽视,应重点关注鱼和无脊椎动物的暴露风险。建议在水生蔬菜生产中谨慎使用吡唑醚菌酯,同时修订吡唑醚菌酯在水生蔬菜上的限量标准。     

甘薯糖蛋白的免疫调节作用研究

初步研究了经ＤＥＡＥ５２和ＳｅｐｈａｄｅｘＧ１００柱层析纯化的北京２号薯糖蛋白的免疫的免疫调节作用。结果表明甘薯糖蛋白浓度达５０μｇ／ｍｌ时可促进ＰＨＡ人外周血淋巴细胞转化,１００μｇ／ｍｌ或者１５０μｇ／ｍｌ时间可显著提高ＰＨＡ刺激的人外周血淋巴细胞转化,刺激指数分别达到６．５和４．５（Ｐ〈０．０５）。腹腔注射甘薯糖蛋白８０ｍｇ／ｋｇ．ｄ可促进小鼠腹腔巨噬细胞的吞噬功能,吞噬指数和吞噬百分数均高     

密度和收割对水蕹菜净水效果的影响

通过在水桶试验中设置2种不同处理方式(密度和收割),研究水蕹菜(Ipomoea aquatic Forsk)对富营养水质的净化特性及效果。结果表明:室外培养12 d,高密度组(10 g/L)对NO2-、NO3-、PO32-、TN、TP和Chl-a的平均去除率最高,分别为90.88%、93.98%、98.96%、82.36%、88.89%和89.33%,显著高于对照组(0 g/L);收割有助于刺激植物加速分蘖、促进植物对N、P元素的吸收固定,并改善水体的DO;水蕹菜组织N、P含量在试验前后发生变化,并与生长水体中的N、P浓度呈正相关关系;植物固定对水体中N、P去除的贡献率与植菜密度呈正相关关系,占高密度组水体中TN、TP去除总量的52.05%和40.41%,为试验组水体中N、P去除的主要途径。     

Patterns of defoliation and their effect on the plant growth and photosynthetic characteristics of Ipomoea cairica

In order to determine the susceptibility of Ipomoea cairica to herbivory, the compensatory growth and photosynthetic characteristics of I. cairica plants were measured after simulated herbivory by leaf trimming in three patterns: leaf‐apex removal, leaf‐edge removal, and perforation. The leaf‐edge removal resulted in a significantly reduced total biomass and root biomass of the plants, but the leaf‐apex removal and perforation had no significant influence on the plant growth. The defoliation patterns had significant effects on the photosynthesis of I. cairica. The net photosynthetic rate and stomatal conductance of the plants whose leaf edges had been removed were the highest among the three defoliation patterns and the fraction of absorbed light that is used in Photosystem II photochemistry increased greatly, while the fraction of light energy that is dissipated thermally decreased. The increased photosynthetic rate as a result of the leaf‐edge removal treatment could be attributed to a decrease in stomatal limitation and an increase in the Rubisco content, as well as higher photosynthetic efficiency and less light energy being dissipated as heat. Increased photosynthesis in the plants whose leaf edges had been removed changed the carbon allocation and resulted in less root development. As the expansion of I. cairica primarily depends on clonal growth, smaller roots could limit its uptake of nutrients from the soil. These direct and indirect effects indicate that leaf‐edge‐feeding herbivores could have potential in the biological control of I. cairica.     

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。     

蕹菜对镉吸收积累及应用研究进展

综述了镉对蕹菜生长的影响,蕹菜对镉的吸收积累和相关机理,以及蕹菜在修复土壤镉污染和安全生产两方面的前景,为研究及应用蕹菜吸收积累镉提供理论参考。     

Highly polymorphic AFLP markers as a complementary tool to ITS sequences in assessing genetic diversity and phylogenetic relationships of sweetpotato (Ipomoea batatas (L.) Lam.) and its wild relatives

Comparative analyses of genetic diversity and phylogenetic relationshipsof sweetpotato (Ipomoea batatas (L.) Lam.) and its wildrelatives in Ipomoea series Batataswere conducted using amplified fragment length polymorphism (AFLP) and sequencedata from the internal transcribed spacer (ITS) region of the ribosomal DNA. LowITS divergence among thirteen species of ser. Batatasresulted in poorly resolved relationships. More variable AFLP characters werefound to be more efficient in characterizing genetic diversity and phylogeneticrelationships at both intra- and interspecific levels within ser.Batatas. Highly informative AFLP fingerprints of 36accessions representing 10 species of ser. Batatas weregenerated using only six primer combinations. Of the species examined,I. trifida was found to be the mostclosely related to I. batatas, whileI. ramosissima andI. umbraticola were the most distantlyrelated to I. batatas. The highlypolymorphic AFLP markers are a valuable tool in assessing genetic diversity andphylogenetic relationships of sweetpotato and its wild relatives.