基于基因组预测和分析甘薯间座壳菌(Diaporthe batatas)分泌蛋白中效应因子

甘薯间座壳菌(Diaporthe batatas)是引起甘薯基腐病的病原菌之一,近年来在中国东南沿海发生较为普遍。由于效应因子在致病过程中发挥着重要作用,本研究采用SignalP 5.0、GPI-SOM、WoLF PSORT、TMHMM-2.0和EffectorP 3.0等生物信息学软件,对甘薯间座壳菌效应因子进行预测和分析。结果表明,从D.batatas全基因组编码的13864个蛋白质中筛选到359个候选效应因子,其中248个为质外体效应因子,68个为胞内效应因子,43个既可能是质外体效应因子又可能是胞内效应因子。在信号肽分析中,所有候选效应因子信号肽长度为14~37个氨基酸,在信号肽切割位点-3位到+2位出现频率最高的氨基酸分别为丙氨酸、丝氨酸、丙氨酸、丙氨酸、脯氨酸。利用HMMER、DIAMOND和eCAMI 3个软件对359个候选效应因子进行碳水化合物活性酶(CAZyme)类分析,结果表明,有89个蛋白质属于CAZyme,其中糖苷水解酶类最多。eggNOG-mapper分析结果显示,在359个候选效应因子中有227个具有功能注释,主要涉及碳水化合物转运和代谢,翻译后修饰、蛋白质周转、分子伴侣等生理过程。通过qRT-PCR检测9个候选效应因子基因在D.batatas侵染过程中的相对表达水平,发现有7个候选效应因子基因在侵染过程中显著上调,有2个没有显著变化。这些结果的获得为明确甘薯间座壳菌效应因子的功能,分析甘薯基腐病发病机理,筛选寄主抗性基因及研发特异性靶向农药提供了参考。

甘薯(Ipomoea batatas L.)遗传转化几个因素的研究

目的：提高甘薯的遗传转化率,为建立快速高效的甘薯遗传转化体系奠定基础。方法：以甘薯多个优良栽培品种无菌苗茎切段为受体,利用农杆菌LBA4404/pSP10Z做介导,研究了影响甘薯转化的几个因素。结果：接种侵染时间对转化效率影响很大,以2-15min为宜,最高转化率可达32.14%;不同基因型的转化受体之间转化率差别较大;在培养过程中最后30min加入终浓度为50μmol/L AS的接种菌侵染的外植体,转化率较对照提高了2.02倍;共培养培养基中加入终浓度为50μmol/L的AS,转化率较对照组提高了6.11倍;AS终浓度为50μmol/L同时pH为4.8的共培养培养基有利于转化的发生,转化率较对照组提高了1.73倍;共培养培养基中脯氨酸的添加并不能提高转化率。结论：该研究为快速高效甘薯遗传转化体系的建立提供了依据。

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。

克服甘薯组(Section batatas)种间杂交不亲和性研究再报

甘薯组A系列野生种I.triloba和B系列栽培种徐薯18杂交授粉后11～20天的胚珠培养获得了试管苗和杂种植株。观察比较了杂种和两亲的形态特征,进行了细胞学鉴定。在同一植株的不同细胞中,染色体数均多于30,但有变异,变动在38～56范围内。杂种植株的花器中,雌雄蕊结构发生变异,全部花朵没有出现雄蕊,雌蕊却有1～5套。用B系列2个野生种和栽培种的6个品种的花粉与杂种植株回交授粉,均不结实。这些异常表现都说明确是种间杂种。近来又应用RAPD鉴定甘薯组种间杂种,进一步证明了种间杂种的真实性。

甘薯(Ipomoea batatas(L.)lam)不定根根尖细微结构的初步研究

顶端分生组织细胞有高的核质比，胞质中可见前质体和其它细胞器．分化的组织原细胞中，皮层原细胞较中柱原和根冠表皮原细胞内前质体增多明显．组织原细胞内的前质体均匀散布高电子密度基质，并以溢痕方式分裂．淀粉颗粒最先出现在分化早期的皮层细胞和根冠表皮细胞中．较大液泡形成先见于根冠表皮细胞原和中柱内的分化早期细胞．外皮层细胞弦向壁纤维化增厚，径向壁薄，具凯氏带结构．提示甘薯不定根尖早期的外皮层细胞可以分化为既具支持保护作用也适应代谢转运功能的单位．

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。

甘薯(Ipomoea batatas)原生质体的分离、培养与根的分化

用甘薯品种农林17号(中紫)的叶柄分离原生质体,对其在添加各种浓度的萘乙酸和激动素的改良细胞薄层培养基中进行悬浮培养。培养1～2 d 后,原生质体再生细胞壁,培养2～3 d 后,再生细胞发生第一次分裂,持续的细胞分裂形成小愈伤组织。悬浮培养的结果表明萘乙酸和激动素的适宜浓度分别为2.0～5.0mg/L 和1.0～5.0mg/L。此后,将小愈伤组织转移到MS 固体培养基上培养,小愈伤组织迅速生长。本试验达到根的分化.

甘薯组(Section Batatas)A系列与B系列种间杂种植株形态变异观察

通过甘薯组 A 系列野生种 I.triloba(2n=30)和 B 系列栽培种甘薯(J.batatas)(2n=90)种间杂交的胚珠培养获得种间杂种植株。对杂种植株生物学特性观察发现:①杂种植株在叶形、叶色、茎粗细、生根习性、开花习性和抗寒性等方面均产生变异。②杂种植株的花器中,雌雄蕊结构发生变异,全部花朵没有出现雄蕊,雌蕊却有1～5枚。③杂种植株体细胞染色体数目变动于2n=27—56范围内,观察平均数为2n=37.25,可确定种间杂种为混倍体。

Cloning and Functional Analysis of Lycopene ε-Cyclase (IbLCYe) Gene from Sweetpotato, Ipomoea batatas (L.) Lam.

This paper reported firstly successful cloning of lycopene ε-cyclase （lbLCYe） gene from sweetpotato, lpomoea batatas （L.） Lam. Using rapid amplification of cDNA ends （RACE）, lbLCYe gene was cloned from sweetpotato cv. Nongdafu 14 with high carotenoid content. The 1 805 bp cDNA sequence oflbLCYe gene contained a 1236 bp open reading frame （ORF） encoding a 411 amino acids polypeptide with a molecular weight of 47 kDa and an isoelectric point （pI） of 6.95. IbLCYe protein contained one potential lycopene ε-cyclase domain and one potential FAD （flavinadenine dinucleotide）/NAD（P） （nicotinamide adenine dinucleotide phosphate）-binding domain, indicating that this protein shares the typical characteristics of LCYe proteins. The gDNA oflbLCYe gene was 4 029 bp and deduced to contain 5 introns and 6 exons. Real-time quantitative PCR analysis revealed that the expression level of IbLCYe gene was significantly higher in the storage roots of Nongdafu 14 than those in the leaves and stems. Transgenic tobacco （cv. Wisconsin 38） expressing [bLCYe gene accumulated significantly more ^-carotene compared to the untransformed control plants. These results showed that lbLCYe gene has an important function for the accumulation of carotenoids of sweetpotato.

Development of SRAP Markers Linked to a Gene for Stem Nematode Resistance in Sweetpotato, Ipomoea batatas (L.) Lam.

Sequence-related amplification polymorphism （SRAP） markers closely linked to stem nematode resistance gene were developed in sweetpotato, lpomoea batatas （L.） Lam. Using bulked segregant analysis （BSA）, 200 SRAP primer combinations were screened with the resistant and susceptible bulked DNA from the 196 progenies of an F1 single-cross population of resistant parent Xu 781xsusceptible parent Xushu 18, 77 of them showed polymorphic bands between resistant and susceptible DNA. Primer combinations detecting polymorphism between the two bulks were used to screen both parents and 10 individuals from each of the bulks. The results showed that primer combination A9B4 produced 3 specific bands in the resistant plants but not in the susceptible plants, suggesting that the markers, named Nspl, Nsp2 and Nsp3, respectively, linked to a gene for stem nematode resistance. Primer combination A3B6 also produced a SRAP marker named Nsp4 linking to the resistance gene. Amplified analysis of the 196 F1 individuals indicated that the genetic distance between these markers and the resistance gene was 4.7, 4.7, 6.3, and 9.6 cM, respectively.

Analysis of drought tolerance and genetic and epigenetic variations in a somatic hybrid between Ipomoea batatas (L.) Lam. and I. triloba L.

The somatic hybrid KT1 was previously obtained from protoplast fusion between sweetpotato （Ipomoea batatas （L.） Lam.） cv. Kokei No. 14 and its wild relative I. triloba L. However, its genetic and epigenetic variations have not been investigated. This study showed that KT1 exhibited significantly higher drought tolerance compared to the cultivated parent Kokei No. 14. The content of proline and activities of superoxide dismutase （SOD） and photosynthesis were significantly increased, while malonaldehyde （MDA） content was significantly decreased compared to Kokei No. 14 under drought stress. KT1 also showed higher expression level of well-known drought stress-responsive genes compared to Kokei No. 14 under drought stress. Amplified fragment length polymorphism （AFLP） and methylation-sensitive amplified polymorphism （MSAP） analyses indicated that KT1 had AFLP and MSAP band patterns consisting of both parent specific bands and changed bands. Fur- ther analysis demonstrated that in KT1. the proportions of Kokei No. 14 specific genome components and methylation sites were much greater than those of I. triloba. KT1 had the same chloroplast and mitochondrial genomes as Kokei No. 14. These results will aid in developing the useful genes ofI. triloba and understanding the evolution and phylogeny of the cultivated sweetpotato.

Identification of QTLs for Starch Content in Sweetpotato(Ipomoea batatas(L.) Lam.)

Sweetpotato （Ipomoea batatas （L.） Lam.） breeding is challenging due to its genetic complexity. In the present study, interval mapping （IM） and multiple quantitative trait locus （QTL） model （MQM） analysis were used to identify QTLs for starch content with a mapping population consisting of 202 F1 individuals of a cross between Xushu 18, a cultivar susceptible to stem nematodes, with high yield and moderate starch, and Xu 781, which is resistant to stem nematodes, has low yield and high starch content. Six QTLs for starch content were mapped on six linkage groups of the Xu 781 map, explaining 9.1-38.8% of the variation. Especially, one of them, DMFN 4, accounted for 38.8% of starch content variation, which is the QTL that explains the highest phenotypic variation detected to date in sweetpotato. All of the six QTLs had a positive effect on the variation of the starch content, which indicated the inheritance derived from the parent Xu 781. Two QTLs for starch content were detected on two linkage groups of the Xushu 18 map, explaining 14.3 and 16.1% of the variation, respectively. They had a negative effect on the variation, indicating the inheritance derived from Xu 781. Seven of eight QTLs were co-localized with a single marker. This is the first report on the development of QTLs co-localized with a single marker in sweetpotato. These QTLs and their co-localized markers may be used in marker-assisted breeding for the starch content of sweetpotato.

Hematological effects of Ipomoea batatas(camote) and Phyllanthus niruri(sampa-sampalukan) from Philippines in the ICR mice(Mus musculus)

Objective:To analyze the hematological effects of administering Ipomoea batatas(I.batatas)and Phyllanthus niruri(P.niruri) in the ICR mice.Methods:Powdered leaves of /.batatas and P.nintri were fed to mice for 4 weeks.A total of six groups were used to determine the effect of the plants to the complete blood count of the mouse.Group A(blank control) mice were feed with pellets only;Group B(negative control) mice were fed with pellets coated with honey;Group C(low dosage) mice were fed with honey-coated pellets and powdered leaves of 1.batatas at 10 g/kg body weight of the mouse;Group D(high dosage) mice were fed with honey-coated pellets and powdered leaves of I,batatas at 20 g/kg body weight of the mouse;Group E(low dosage) mice were fed with honey-coated pellets and powdered leaves of P.niruri at 10 g/kg body weight of the mouse:and Group F(high dosage) mice were fed with honey-coated pellets and powdered leaves of P.niruri at 20 g/kg body weight of the mouse.Complete blood count was performed on Days 0.14 and 28.Results:It was shown that I.batatas can increase the values of hematocrit and hemoglobin on both the low dose and high dose at Day 28 and red blood cells(RBC) on both Days 14 and28 of testing.On the other hand.P.niruri can increase RBC.hematocrit and hemoglobin on Day 28 with only the low dose.There were no significant differences with white blood cell,absolute granulocyte,lymphocyte and monocyte,and platelet counts observed for both plant samples.Conclusions:I.batatas and P.niruri have effects on the hematocrit,RBC and hemoglobin levels in mice.

Correlation of phytochemical content with antioxidant potential of various sweet potato (Ipomoea batatas) in West Java, Indonesia

Objective: To determine antioxidant activity and phytochemical content from various tubers extracts of sweet potato(Ipomoea batatas) and to explore the correlation of phytochemical content with their antioxidant activities. Methods: Antioxidant activities were tested using DPPH and FRAP assays. Total phenolic was calculated by Folin-Ciocalteu reagent, flavonoid content by Chang's method and correlation with their antioxidant activities were analyzed by Pearson's method. Results: PO2 showed highest antioxidant activity, which had the lowest IC50 DPPH(10.54 μg/m L) and the lowest EC50 FRAP(11.14 μg/m L). PO2 showed the highest total phenolic(11.91 g GAE/100 g) and total flavonoid content(17.83 g QE/100 g). There were significantly negative correlation between total phenolic content and flavonoid content in sample PO with their IC50 DPPH and EC50 FRAP. IC50 DPPH of sample PP and PO showed significantly positive correlation with their EC50 FRAP. Conclusions: Result of DPPH method shows that all different ethyl acetate and ethanolic tubers extracts of four varieties of sweet potato are classified as strong and very strong antioxidant. Result of DPPH and FRAP methods indicates that phenolic and flavonoid compounds in sample PO contributes together to antioxidant activities. Antioxidant activities of sample PP and PO by DPPH method are linear to FRAP method.

Effect of Dioscorea batatas on longitudinal bone growth rate in adolescent female rats

OBJECTIVE The root of Dioscorea batatas,rich in steroidal saponins,alkaloids,tannins,phytosterols,and starch,is an herbal medicine of tonifying qi and nourishing stomach after invigorating spleen with a long history of safe use for treatment of chronic dysentery and weakness of the spleen and stomach in Korea.This study was aimed to investigate the effect of D.batatas on longitudinal bone growth rate in adolescent female rats.METHODS D.batatas was extracted with 30% EtOH for 3h at 90℃in a reflux apparatus.In two groups,we administered a twice daily dosage of D.batatas extract(at 30 and 300mg·kg-1,respectively)per os for 4d,and in a control group,we administered vehicle only under the same conditions.Recombinant human growth hormone(rhGH)was subcutaneously injected once daily.All rats were born at same day(33d-old).On day 3,tetracycline was injected intraperitoneally to form a fluorescent band on the growth plates.RESULTS The bone growth rate in groups administered D.batatas 300mg·kg-1 and rhGH was significantly increased to 343.8±20.7,and 359.6±30.2μm·d-1 respectively from control group,320.7±23.2μm·d-1.No difference was observed in the amount of food intake or mean body weight among all groups during the acclimation or administration period.CONCLUSION These results suggest that D.batatas extracts have the potential to induce height increase;however,further research,including clinical trials,is necessary.

Identification and Quantification of Allelochemicals from Selected Sweet Potato (<i>Ipomoea batatas</i>(L.) Lam.) Cultivars

Allelopathic compounds have the potential to inhibit the growth and development of other organisms in a diverse manner ranging from shifting nutrients and enhancing their growth to inflicting diseases. In addition, these compounds influence seedling growth and seed germination of various crops. The goal of this study was to identify and quantify different allelochemicals in various sweet potato cultivars through high-performance liquid chromatography techniques. Selected sweet potato slips (weight: 2.0 - 2.5 grams/slip) were propagated in separate glass tubes filled with 10.0 mL distilled water. Water extract from each glass tube was collected after 2, 4, and 6 weeks after transplanting (WAP) to identify and quantify allelochemical compounds by comparing their peaks with the retention time of standards. Results show that the concentration of allelochemicals in water extract was increased from 2 to 4 WAP but remained constant in the sixth week. Quantitative analysis revealed that the amount of chlorogenic acid was higher in all sweet potato cultivars compared to other allelochemicals. Some sweet potato cultivars, A5 and A39, exhibited higher allelopathy (18.28 - 19.37 ppm/slip) and reduced the height and biomass of Palmer amaranth the most due to the presence of increased concentration of combined allelochemicals, while other cultivars produced lesser allelochemicals (10.90 ppm/slip) and did not reduce the growth of the weed species. Allelopathic sweet potato cultivars high in chlorogenic acid production can effectively suppress Palmer amaranth with minimal dependence on chemicals to manage weeds and harmful pests under sustainable agricultural system.

Cloning and Characterization of Eukaryotic Translation Initiation Factor 4E (eIF4E) Gene Family in Ipomoea batatas L. (Lam) for Understanding Hexaploid Sweetpotato-Virus Interactions

Characterization of genes related to sweetpotato viral disease resistance is critical for understanding plant-pathogen interactions, especially with feathery mottle virus infection. For example, genes encoding eukaryotic translation initiation factor (eIF)4E, its isoforms, eIF(iso)4E, and the cap-binding protein (CBP) in plants, have been implicated in viral infections aside from their importance in protein synthesis. Full-length cDNA encoding these putative eIF targets from susceptible/resistant and unknown hexaploid sweetpotato (Ipomoea batatas L. Lam) were amplified based on primers designed from the diploid wild-type relative Ipomoea trifida consensus sequences, and designated IbeIF4E, IbeIF(iso)4E and IbCBP. Comparative analyses following direct-sequencing of PCR-amplified cDNAs versus the cloned cDNA sequences identified multiple homeoalleles: one to four IbeIF4E, two to three IbeIF(iso)4E, and two IbCBP within all cultivars tested. Open reading frames were in the length of 696 bp IbeIF4E, 606 bp IbeIF(iso)4E, and 675 bp IbCBP. The encoded single polypeptide lengths were 232, 202, and 225 amino acids for IbeIF4E, IbeIF(iso)4E, and IbCBP, with a calculated protein molecular mass of 26 kDa, 22.8 kDa, and 25.8 kDa, while their theoretical isoelectric points were 5.1, 5.57, and 6.6, respectively. Although the homeoalleles had similar sequence lengths, single nucleotide polymorphisms and multi-allelic variations were detected within the coding sequences. The multi-sequence alignment performed revealed a 66.9% - 96.7% sequence similarity between the predicted amino acid sequences obtained from the homeoalleles and closely related species. Furthermore, phylogenetic analysis revealed ancestral relationships between the eIF4E homeoalleles and other species. The outcome herein on the eIF4E superfamily and its correlation in sequence variations suggest opportunities to decipher the role of eIF4E in hexaploid sweetpotato feathery mottle virus infection.

Comparison of Physicochemical,Organoleptic and Nutritional Abilities of Eight Sweet Potato(Ipomoea batatas)Varieties

In Martinique (F.W.I.), biodiversity of vegetable varieties remain unexploited due to public unawareness or supply problems. To further enhance the sweet potato, physicochemical, sensory and nutritional characteristics of eight varieties of sweet potato were established. The eight sweet potatoes cultivars were noticeably diverse with phenotypic, sensory, physicochemical and nutritional characteristics which were very varied. The eight cultivars grown in Martinique were advantageously positioned in relation to the globally identified sweet potato, regarding fibre, starch, potassium, copper, vitamin B1, B3 and B9 contents. Compared to the ordinary potato, Martiniquan sweet potatoes have a much better nutritional potential. Energy value and vitamin C levels were twice as much as in normal potatoes. Martiniquan sweet potatoes cultivars were also richer in minerals and vitamins, with 2.7 times more vitamin B9 and 63 times more beta-carotene than the ordinary potato.

甘薯(Ipomoea batatas L.Lam.)基因启动子在根癌农杆菌中的作用

作者曾用自行构建的启动子探针型载体ｐＳＵＰＶ４，从甘薯（ＩｐｏｍｏｅａｂａｔａｔａｓＬ．Ｌａｍ．）总ＤＮＡ中克隆到了６５个在大肠杆菌中具有启动基因表达功能的ＤＮＡ片段．现研究发现，甘薯基因启动子片段在根癌农杆菌中也具有启动基因转录的功能，其启动功能的大小与启动子片段在大肠杆菌中启动卡那霉素抗性基因表达活性呈正相关，即原来卡那霉素抗性越高的，ＧＵＳ基因的酶活性越高．利用重组子ｐＩＢ２中插入片段所做的Ｓｏｕｔｈｅｒｎ杂交实验证实，该ＤＮＡ片段来源于甘薯基因组．

Different Susceptibility in the Two Sympatric Sweet Potato Weevils, Cylas formicarius and Euscepes postfasciatus, to the Entomopathogenic Fungus Metarhizium anisopliae

Laboratory and field experiments were performed to evaluate the pathogenicity of an isolate of the entomopathogenic fungus Metarhizium anisopliae to the two sympatrically occurring weevil species, Cylas formicarius and Euscepes postfasciatus. In the laboratory bioassays, suspension of conidia, ≥106 CFU/mL, caused mortalities > 80% on adults of both weevils in seven days after inoculation. It took longer time 20 days for grain formulation of the isolate adhered on rice grains of ≥5 g/m2 (107 CFU/g) to attain similar mortalities of E. postfasciatus, but no evident mortality was obtained in C. formicarius. The grain formulation was thus less effective on C. formicarius than the suspension. Field trials were carried out over two years from 2013 to 2014, in which adults of E. postfasciatus were released two times during the field experiments for enhancement of damage on plants by this weevil, whereas the other weevil species was left to naturally invade the experimental plots by flying. The results of the experiments revealed in both years that two applications of the isolate in grain formulation, equivalent to 50 kg/hectare, sprayed manually over the ground surface reduced the infestation of plants and tuber damage by weevils of both species as much as the conventional chemical insecticide applications. The occurrences of weevils at harvest were not significantly different among treatments. The potential and possible uses of the fungus are discussed for the management of these two weevil species.