Tuberous Roots Of Sweet Potato Research Articles

Bacterial endophytes of sweet potato tuberous roots affected by the plant genotype and growth stage

This study aimed to characterize the endophytic bacterial communities in the tuberous roots of three sweet potato genotypes, IPB-149, IPB-137 and IPB-052. The hypothesis is that plant genotype and growth stage influence bacterial composition. Using cultivation-independent (Polymerase chain reaction-denaturing gradient gel electrophoresis–PCR-DGGE–based on 16S rRNA gene fragments and DNA sequencing) and cultivation-dependent (bacterial isolation) methods it was shown that plant growth stage influenced the endophytic bacterial communities, and that plant genotypes also significantly influenced these communities, but only at the first sampling (three months after planting). A total of 93 strains were isolated from the roots of the different genotypes, and 59 groups were revealed by BOX-PCR. Bacteria from the Proteobacteria, Actinobacteria and Firmicutes phyla were found, and Bacillus strains predominated in the roots of IPB-052 and IPB-149 (72% and 79%, respectively). Almost half of the strains isolated from IPB-137 roots (47%) were Gammaproteobacteria. In addition, the isolates were tested for antimicrobial substance and indole acetic acid production, organic and inorganic phosphate solubilization, siderophore production and for the presence of nitrogenase gene. All isolates with antagonistic activity against the sweet potato-pathogenic fungus Plenodomus destruens belong to the genus Bacillus. Indole acetic acid production was predominantly found among the strains isolated from IPB-137; once again suggesting an influence of the sweet potato genotype on its endophytes.

Effects of several Factors for Ridge on the Tuberous root of Sweetpotato

Effects of several Factors for Ridge on the Tuberous root of Sweetpotato

Temporal patterns of gene expression associated with tuberous root formation and development in sweetpotato (Ipomoea batatas).

BackgroundThe tuberous root of sweetpotato is undisputedly an important organ from agronomic and biological perspectives. Little is known regarding the regulatory networks programming tuberous root formation and development.ResultsHere, as a first step toward understanding these networks, we analyzed and characterized the genome-wide transcriptional profiling and dynamics of sweetpotato root in seven distinct developmental stages using a customized microarray containing 39,724 genes. Analysis of these genes identified temporal programs of gene expression, including hundreds of transcription factor (TF) genes. We found that most genes active in roots were shared across all developmental stages, although significant quantitative changes in gene abundance were observed for 5,368 (including 435 TFs) genes. Clustering analysis of these differentially expressed genes pointed out six distinct expression patterns during root development. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that genes involved in different processes were enriched at specific stages of root development. In contrast with the large number of shared expressed genes in root development, each stage or period of root development has only a small number of specific genes. In total, 712 (including 27 TFs) and 1,840 (including 115 TFs) genes were identified as root-stage and root-period specific, respectively at the level of microarray. Several of the specific TF genes are known regulators of root development, including DA1-related protein, SHORT-ROOT and BEL1-like. The remaining TFs with unknown roles would also play critical regulatory roles during sweetpotato tuberous root formation and development.ConclusionsThe results generated in this study provided spatiotemporal patterns of root gene expression in support of future efforts for understanding the underlying molecular mechanism that control sweetpotato yield and quality.Electronic supplementary materialThe online version of this article (doi:10.1186/s12870-015-0567-5) contains supplementary material, which is available to authorized users.

Sweet Potato Production for Bio-ethanol and Food Related Industry in Indonesia: Challenges for Sustainability

As an underground crop, tuberous root of sweet potato (Ipomoea batatas) is the main economical yield expected from various level of cultivation. Aside rich in carbohydrate, sweet potato root contains vitamin and mineral. The degree of utilization reflects the level of subsistence to commercialization, where the desire or needs can be easily met was defined as prosperity. Supplying continuously the demand of sweet potato for subsistence and commercialization oriented to bio-ethanol and food related industries depend on the sustainable production system. To sustain sweet potato production system, the severe biotic and a-biotic stresses have to be alleviated.

Sweet potato tuberous roots yield under different soil managements

Este trabalho objetivou avaliar a produtividade de raízes tuberosas de batata-doce em diferentes sistemas de preparo do solo e épocas de colheita. O delineamento experimental foi em blocos ao acaso, em esquema de parcelas subdivididas. As parcelas corresponderam a quatro sistemas de preparo do solo: preparo convencional com palha de Urochloa decumbens incorporada e confecção de leiras (PCCP), preparo convencional sem palha e com confecção de leiras (PCSP), preparo reduzido com manutenção de palha na superfície (PRCP) e preparo reduzido sem palha (PRSP); e as subparcelas, a quatro épocas de colheita: 90, 120, 150 e 180 dias após plantio. Entre os sistemas estudados, a cultura da batata-doce apresenta maiores produtividades total e comercial de raízes tuberosas em função de maiores números total e comercial de raízes tuberosas em solo manejado sob preparo convencional, tanto com (PCCP) como sem palha (PCSP). Assim, o preparo convencional do solo é mais adequado ao cultivo da batata-doce.

Propriedades físicas de solo em diferentes sistemas de preparo para o cultivo da batata-doce

This study aimed to assess the impact of tillage systems on physical properties of an Alfissol type soil and on the growth of sweet potato tuberous roots. To assess the soil physical properties, an experiment was conducted in randomized blocks design, in split-plot scheme. The plots consisted of the treatments conventional tillage with making mounds and straw incorporated, conventional tillage with making mounds and without straw, reduced tillage with straw on the soil surface and reduced tillage without straw; and the subplots, to collect periods. The soil physical properties evaluated were soil bulk density, total soil porosity, soil macroporosity and soil microporosity, soil resistance to penetration and gravimetric soil water. For the assessment of the growth of sweet potato tuberous roots, it was adopted an experiment where the plots corresponded to the soil management forms and subplots to four collect periods: 90, 120, 150 and 180 (DAP). The length / roots diameter of individual roots relations were avaluated. It was concluded that the reduced tillage gives greater soil resistance to penetration of roots, by reducing the vertical growth of roots, and the presence of straw incorporated in the conventional tillage favors maintenance of lowest soil bulk density and highest soil macroporosity along the time.

Relationship between invertase gene expression and sucrose concentration in the tuberous roots of sweet potato (Ipomoea batatas L. Lam.) during cold storage

SummaryLow sweetness in freshly-harvested tuberous roots is an undesirable characteristic of the sweet potato (Ipomoea batatas L. Lam.) cultivar, ‘Kokei 14’. In the present study, we sought to characterise the biochemical and molecular aspects of sucrose accumulation in the tuberous roots of ‘Kokei 14’ during cold storage in comparison with another sweet potato cultivar, ‘Beniazuma’. The tuberous roots of both cultivars were harvested and stored at 4ºC for 30 d. The sucrose, fructose, and glucose concentrations, the activities of two sugar-metabolising enzymes, and the expression of six sucrose-cleaving acid invertase (AI) genes were monitored. Exposure to chilling temperatures (4ºC) for up to 30 d increased the sucrose concentration in the tuberous roots of ‘Kokei 14’, but not in those of ‘Beniazuma’. In line with this phenomenon, we found that the activity of AI was suppressed to approx. 0.4-times the pre-treatment value in ‘Kokei 14’, but increased to 2.7-times the pre-treatment value in ‘Beniazuma’ during cold storage for 30 d.The patterns and levels of expression of six genes encoding AIs indicated that the protein encoded by IbAINV1 was the main AI that degraded sucrose in the tuberous roots of both cultivars. IbAINV1 gene expression increased transiently and reached a maximum (2.3-times the pre-treatment value) at 20 d in ‘Beniazuma’, whereas it decreased to approx. 0.14-times the pre-treatment value by 10 d in ‘Kokei 14’ and remained low for the duration of the experiment. Sucrose concentrations did not change in the tuberous roots of ‘Kokei 14’ stored at 13ºC for 20 d. Therefore, we conclude that the accumulation of sucrose in the tuberous roots of ‘Kokei 14’ was caused mainly by suppression of IbAINV1 gene expression in response to chilling.

Produtividade da cultura da batata-doce em diferentes sistemas de preparo do solo

Trabalhos sobre preparo reduzido em solos cultivados com raízes e tubérculos são escassos e controversos. Este trabalho objetivou avaliar e comparar a produtividade de raízes tuberosas de plantas de batata-doce cultivadas em argissolo vermelho-amarelo sob preparo convencional (aração seguida de gradagem niveladora e posterior levantamento de leiras com sulcador) e sob preparo reduzido com manutenção de palhada superficial (sem revolvimento do solo, exceto nas linhas de plantio). O delineamento experimental foi em blocos ao acaso, em esquema de parcelas subdivididas. As parcelas principais corresponderam aos tratamentos preparo convencional (com confecção de leiras) e preparo reduzido, e as subparcelas, às quatro épocas de coleta: 90, 120, 150 e 180 dias após plantio. Foram avaliadas as características: produtividades total e comercial, números de raízes tuberosas total e comercial, e massa de matéria fresca individual média das raízes tuberosas consideradas comerciais. A cultura da batata-doce apresentou produtividades total e comercial de raízes tuberosas 68 e 75% superiores no plantio convencional, respectivamente, em relação ao preparo reduzido, em função de maiores números total e comercial de raízes tuberosas em solo preparado de maneira convencional. Não houve diferença entre os manejos de solo quanto à massa de matéria fresca individual de raízes tuberosas. Concluindo, o preparo convencional do solo é mais adequado ao cultivo da batata-doce.

In situ observation of crystallinity disruption patterns during starch gelatinization

Twelve starches were isolated from the tuberous root of sweet potato, the rhizomes of lotus and yam, the tuber of potato, the corm of water chestnut, and the seeds of pea, bean, barley, wheat, lotus, water caltrop, and ginkgo. Their gelatinization processes were in situ viewed using a polarizing microscope in combination with a hot stage. Four patterns of crystallinity disruption during heating were proposed. The crystallinity disruption initially occurred on the proximal surface of the eccentric hilum, on the distal surface of the eccentric hilum, from the central hilum, or on the surface of the central hilum starch granule. The patterns of initial disruption on the distal surface of the eccentric hilum and on the surface of the central hilum starch were reported for the first time. The heterogeneous distribution of amylose in starch granule might partly explain the different patterns of crystallinity disruption and swelling during gelatinization.

A proteomic analysis of storage stress responses in Ipomoea batatas (L.) Lam. tuberous root

During post-harvest storage, tuberous roots of sweet potato (Ipomoea batatas L. Lam.) usually undergo a biotic and abiotic stress influencing protein expression pattern and substance contents. This research compared the change of total proteins and carbohydrate content in tuberous roots of sweet potato during the storage period. The result of the two-dimensional electrophoresis analysis demonstrated that there were 25 differentially expressed proteins between day 0 and day 75 during the storage. Among these proteins, 11 proteins were down-regulated and the other 14 were up-regulated. The results from MALDI-TOF-TOF/MS analyses and mascot database searching showed that 11 of the 25 differentially expressed proteins were identified as store-stress regulated proteins. It was also found that the proteins involved in the energy metabolism and the stress-response were drastically up-regulated, whereas those in biomacromolecule synthesis were markedly down-regulated. Meanwhile, under the experimental conditions, the content of the starch and the cellulose was decreased by more than a quarter and the amylase activity was increased moderately.

Batatins III–VI, glycolipid ester-type dimers from Ipomoea batatas

Batatins III–VI ( 1– 4), glycolipid ester-type dimers, were isolated from the tuberous roots of sweet potato ( Ipomoea batatas) using recycle high performance liquid chromatography. Their structures were characterized by means of several high-resolution NMR and mass spectrometry techniques. These compounds are the first examples of ester-type dimers which consist of two units of the heterotetrasaccharide operculinic acid C. Each unit was esterified by a different amount and type of acid residues: (2 S)-methylbutanoic, cinnamic, decanoic (capric) and dodecanoic (lauric) acids. Batatins III–VI ( 1– 4) are an example of the presence of a large number of resin glycoside congeners in each morning glory species caused by partial acylation of their constitutive saccharide cores.

Effects of Storage Conditions on Deterioration of Mechanically Injured Sweet Potato Tuberous Roots, Especially on Induction of Ipomeamarone

Effects of Storage Conditions on Deterioration of Mechanically Injured Sweet Potato Tuberous Roots, Especially on Induction of Ipomeamarone

Proteomic Alteration During Dormant Period of Curcuma Longa Rhizomes

Proteins involved during storage of Curcuma longa have not been investigated in detail. Proteins and nucleic acids are considered to be essential for the sprouting period. As numerous applications of proteomic approaches have been reported in many areas of biology, biochemistry and biomedicine, we chose to use proteomic technology to study the protein expression of Curcuma longa (Khaminchun) rhizome during dormancy and sprouting. Microscale solution-phase isoelectric focusing (Zoom) was employed to enrich the low abundance proteins in the pH range of 5.4-10 and improve the separation of those proteins in the acidic range from 3-5.4. Samples were drawn at seven-day intervals from harvest until the commencement of sprouting. The proteomic patterns of the storage period (0, 14, 21, 42, and 70 days) were studied and identified by LC/MS/MS in these two pH ranges. High levels of glyceraldehyde-3-phosphate dehydrogenase, a glycolytic enzyme, were present and in glycosylated and phosphorylated forms. Sporamin, the major storage protein of the tuberous roots of sweet potato, was highly expressed in the dormant period and lower expression was detected in the sprouting period. Moreover, the enzyme for catalyzing the synthesis of catechin, leucoanthocyanidin reductase, was found for the first time in the Curcuma longa rhizome. These results represent the first proteomic patterns during the storage period of Curcuma longa. For the rhizomes of Curcuma longa, visible sprouting was observed within 70 days after harvest.

Proteomic Alteration During Storage of Curcuma Longa Rhizomes

The rhizomes of genus Curcuma are extensively used as spices, food preservatives, coloring materials, cosmetics and medicines. The Curcuma becomes dormant during the dry season. The changes in proteins during storage of Curcuma longa have not been investigated in detail. We employed proteomic technology to study the protein expression from the day of harvest to the commencement of sprouting of Curcuma longa. The two dimensional gel electrophoresis patterns (pH 4-7) of the rhizomes showed a high abundance of proteins with pI in the range of 3-5 and low abundance with pI in the range of 5-7. Microscale solution-phase isoelectric focusing (Zoom) was employed to enrich the low abundance proteins in the pH range of 5.4-10 and improve the separation of those proteins in the acidic range from 3-5.4. The total storage period was 77 days. Samples were drawn at an interval of 7 days from the harvest until sprouting. The proteomic patterns of the storage period (0, 7, 14, 21, 35, 42, 49 and 70 days) were studied in these two pH ranges. In the pH range from 3-5.4, the expression of ribulose 1, 5-bisphosphate dehydrogenase, actin, anionic peroxidase swpa4, maturase and photosystem I assembly protein ycf4 were increased and putative oxygen evolving enhance protein I, hypothetical protein MeviPp13 and MLP_like protein 423 were decreased from 0 to 70 days, while in the pH range from 5.4-10, the expression of eight identified proteins were expressed only at 70 days. Sporamin, the major storage protein of the tuberous roots of sweet potato was highly expressed in the dormancy period and lower expression seen in the sprouting period

Effects of application of sucrose and cytokinin to roots on the formation of tuberous roots in sweetpotato (Ipomoea batatas (L.) Lam.)

Effects of sucrose and cytokinin (trans-zeatin riboside (t-ZR)) on the formation of tuberous root of sweetpotato (Ipomoea batatas (L.) Lam.) were studied by directly applying these substances to young roots. In the roots that originally contained approximately 9 μg of en- dogenous sucrose per milligram of fresh weight (FW), further increase in the sucrose level did not necessarily result in tuberous root formation, whereas t-ZR application invariably induced tuberous root formation. However, t-ZR did not induce morphogenesis when the sucrose level in the root was lowered to approximately 2 μg mg -1 of FW. Our results imply that high levels of en- dogenous sucrose are necessary for tuberous root formation and that in the presence of high sucrose concentrations, cytokinins can trigger tuberous root formation.

Non-contact Measurements of Storage Organ Growth in Fruit and Root Crops

Continuous measurement of the growth of a storage organ is often required for analyzing environmental effects on crop production. Various techniques have been used for measuring storage organ growth. Non-contact methods are desirable for the growth analysis of an intact storage organ. Recently, laser beam-based measuring devices have been widely utilized in the industry for non-contact measurements of the width, length, or thickness of an object. These devices can also be effective tools for evaluating storage organ growth in plants. This article presents successful examples of the use of laser beam-based devices for non-contact growth measurements of two different types of storage organs, i.e., a tomato fruit and a sweetpotato tuberous root.

Endogenous Hormone Concentration in Developing Tuberous Roots of Different Sweet Potato Genotypes

A field trial was conducted to investigate the changes of endogenous hormone concentration (EHC) during formation and thickening of tuberous roots in sweet potato ( Ipomoea batatas L.) of different genotypes: Xushu 18, Minamiyutaka, and I. trifida-K123. The results of this study suggested that the concentrations of zeatin riboside (ZR), dihydro-zeatin riboside (DHZR), abscisic acid (ABA), indole-3-acetic acid (IAA), and isopentenyl-adenine (IPA) of Xushu 18 and Minamiyutaka were significantly higher than those of I. trifida-K123. Dry tuberous root yields were positively correlated with the concentration of ABA, ZR, and DHZR at 1 or 5% significant level, but were not obviously correlated with the concentrations of IAA, IPA, and GA 4. The concentrations of ABA, ZR and DHZR played very important roles in the tuberous root formation and thickening in sweet potato. The concentrations of ZR, DHZR, ABA, and IAA in the upper or inner portion of tuberous roots were significantly higher than those toward the end of the root or its outer portion. Meanwhile, EHC of large-sized tuberous roots were significantly higher than those of medium- or small-sized tubers during the early thickening period. In the rapid thickening period of tuberous roots, EHC of medium-sized tubers were the highest. However, at the late-thickening period, EHC of small-sized tubers ranked the highest.

New gene construction strategy in T-DNA vector to enhance expression level of sweet potato sporamin and insect resistance in transgenic Brassica oleracea

Sporamin, an abundant storage protein in tuberous roots of sweet potato, possesses strong inhibitory activity against trypsin and pest-resistance. To promote consistent high-level expression of sporamin and insect resistance in transgenic Brassica plants, a wound-responsive sporamin promoter (Pspoa) alone or combined with matrix-attached-region-like DNA segment (spoMAR) were constructed for driving sporamin cDNA. The results showed the transgenic plants containing Pspoa-drived sporamin and spoMAR displayed the highest level and low inter-transformant variability of sporamin expression, and the ability of insect resistance of transformants positively correlated with sporamin activity. Furthermore, expressions of Pspoa-drived sporamin especially combined with the spoaMAR retains high and steady levels in the T1 and T2 generations, in marked contrast to the variable expression patterns observed in CaMV35S promoter-driven transformants. This study evidently indicates that the Pspoa and spoaMAR would be very efficient for high transgene expression in plants and obtaining inherently stable transformants in consecutive progenies.

Purification of Trypsin Inhibitor from Sweet Potato by Applying Immobilized Trypsin on Glutaraldehyde Activated Chitosan Beads

Immobilized trypsin on the glutaraldehyde activated chitosan beads was employed to purify trypsin inhibitor from the tuberous roots of sweet potato by means of affinity chromatography. The optimum conditions for the preparation of immobilized trypsin were investigated, and a maximum trypsin activity of 10 unit/g-beads was achieved in this study. Fifty-six percent of the activity of the trypsin inhibitor in the crude extract of sweet potato could be recovered through affinity chromatography. Seven visible bands by SDS-PAGE were suspected to be trypsin inhibitors, and all of the molecular weights were more than 20kDa.

Changes in Carbohydrate Content and Gene Expression During Tuberous Root Development of Sweet Potato

To understand the carbohydrate metabolism during the developmental process of tuberous roots in sweet potato (Ipomoea batatas), changes in carbohydrate content of the tuberous roots and expression of three genes, encoding granule-bound starch synthase, sporamin and β-amylase responsible for the synthesis of two major abundant components, starch and protein, were examined during different stages of tuberization. Results showed that the expression of genes, starch and sucrose content were highly correlated with the size of tuberous roots suggesting that fresh weight should be more suitable than growing-day to serve as an indicator for defining developmental stages. Increase in sucrose concentration during development might play an important role in starch accumulation; not only it functions as a substrate for starch synthesis but it can also stimulate the transcription of granule-bound starch synthase gene.