Dioscorea Rotundata Research Articles

Effect of Plant Growth Hormones and Liquid Fertilizer on Rooting and Tuberization of Yam (<i>Dioscorea rotundata</i> Poir.) Vine Cuttings

Vine cutting is an effective solution to solve the problem of seed availability in yam cultivation. This study was conducted to improve the recovery and rooting rate of vine cuttings of Dioscorea rotundata. Two-node cuttings from five (5)-month-old hybrid plants were grown in liquid media consisting of phytohormones (AIA3 and GA3) and liquid fertilizer (NPK 8-8-8) at different concentrations. Observations were made weekly from the 21st day after transplanting and focused on the survival rate of the cuttings, the number of roots emitted and the number of minitubers initiated. The results obtained showed a significant effect of the different growing media on the survival rate, rooting and production of minitubers. The best survival rates were obtained for cuttings grown in NPK (8-8-8) at 0.25% (100%) and AIA3 at 25 ppm (93.3%). The highest averages root number was recorded with growing media containing 0.25% NPK 8-8-8 (20.3) and 25 ppm AIA3 (17.7). Growing media with 0.25% NPK (8-8-8) and 25 ppm AIA3 provided the highest average numbers of minitubers initiated, respectively 5 and 4.6. Growing medium containing 0.25% NPK 8-8-8 has been identified as the one that allows better roots emission and minitubers production by yam vines cuttings.

Evaluation of Crude Yam Starch from White Yam (Dioscorea rotundata poir.) as a Pharmaceutical Excipient in Tableting of Paracetamol

Evaluation of Crude Yam Starch from White Yam (Dioscorea rotundata poir.) as a Pharmaceutical Excipient in Tableting of Paracetamol

Comparative Effect of Poultry and Swine Manures on the Performance of White Guinea Yam (Dioscorea rotundata Poir) in an Ultisols Environment

White Guinea yam (Dioscorea rotundata Poir) is an important staple food in a number of African countries, including Nigeria and Ghana. However, the tuber yield in these areas is below its potential yield. The most probably constraint to low tuber yield is the low soil nutrient status. A field trial was conducted at the Experimental Farm of the Department of Crop Science, Faculty of Agriculture, University of Benin, Benin City, Nigeria, between April and November 2016 and 2017, to evaluate the effect of poultry and swine manures on the growth and tuber yield of white Guinea yam (D. rotundata) in an ultisols environment. The trial was laid out in a 2 × 3 split plot arrangement fitted into randomized complete block design with three replicates. The main plots were organic fertilizers (poultry and swine manures) and the sub-plots were represented by three rates (0, 300 and 450 kg N ha-1) of application. Data collection on growth characters were on vine length (cm), vine girth (cm), number of nodes, number of leaves and leaf area index. At harvest, tuber length (cm), tuber girth (cm), number of tubers per plant, tuber weight and tuber yield (t ha-1) were also evaluated. The results showed that growth and yield variables varied significantly (p < 0.05) with organic fertilizer types and application rates. Poultry manure treated plants produced higher (p < 0.05) number of nodes and leaves than swine manure treated plants. Application rates of 300 and 450 kg N ha-1 of poultry manure significantly increased vine length, vine girth, number of nodes and leaves as well as leaf area index. Tuber weight and yield were higher in plants treated with poultry manure with the application rates of 300 and 450 kg N ha-1 performed better than control in 2016, while the application rate of 300 kg N ha-1 had the highest tuber weight and yield in 2017. Application rates of 300 and 450 kg N ha-1 performed better than the control (0 kg N ha-1) in 2016. However, in 2017, application rate of 300 kg Nha-1 had the highest tuber weight and yield. The present study suggests that poultry manure at application rate of 300 kg N ha-1 could be adopted by white Guinea yam farmers for high productivity of the crop under intense and continuous cropping in humid ultisols environment.

Fungicidal Effect of Some Plant Extracts against Tuber Dry Rot of White Yam (Dioscorea Rotundata Poir) Caused by Aspergillus Niger

In vitro study was carried out to test the efficacy of Azadirachta indica A. Juss. (Neem), Nicotiana tabacum Linn. (Tobacco), rhizomes of Zingiber officinale Rosc. (Ginger) leaves of Carica papaya Lam. (pawpaw) and seeds of Piper nigrum Linn. (Black pepper) and a chemical fungicide (mancozeb) at three concentrations of plant extracts (30, 60 and 90 g/L) and mancozeb (4, 8 and 12 g/L). The concentrations were amended in potato dextrose agar (PDA). A. Niger was isolated from rotted tissues of yam tubers obtained from Kadarko in Keana Local Government Area of Nasarawa State, Nigeria. The research was conducted at Advanced Plant Pathology Laboratory, Federal University of Agriculture, Makurdi, Nigeria. Results revealed that P. nigrum and Z.officinale were the best in fungi toxicity against A. niger at their respective concentrations throughout the period of incubation. This was followed by C. papaya, A. indica and N. tabacum respectively. Mancozeb gave 100 % inhibition at all concentrations tested throughout the period of incubation. Though all the extracts at all concentrations produced significant inhibitory effect (P ≤ 0.05) on mycelial growth of A. niger; the concentrations of 60 g/L and 90 g/L of the plant extracts and 4 g/L of mancozeb were considered more effective and are therefore, recommended for the control of A. niger. This has shown that there is high potential in these natural plant products for the control of yam disease if properly harnessed to replace chemical fungicide which are often harmful to the environment, toxic to man and very costly to purchase. Keywords: A. Niger; Concentrations; Fungitoxic; Inhibition; Mancozeb; Plant extracts;

Non-destructive shoot biomass evaluation using a handheld NDVI sensor for field-grown staking Yam (Dioscorea rotundata Poir.)

ABSTRACT Crop phenotyping is a key process used to accelerate breeding programs in the era of high-throughput genotyping. However, most rapid phenotyping methods developed to date have focused on major cereals or legumes, and their application to minor crops has been delayed. In this study, we developed a non-destructive method to predict shoot biomass by measuring spectral reflectance in staking yam (Dioscorea rotundata). The normalized difference vegetation index (NDVI) was evaluated using a handheld sensor that was vertically scanned from the top to the bottom of a plant alongside the stake. A linear regression model was constructed to predict shoot biomass through Bayesian analysis using NDVI as a parameter. The model well predicted the observed values of shoot biomass, irrespective of the growth stage and genotypes. Conversely, the model tended to underestimate the shoot biomass when the actual shoot biomass exceeded 150 g plant−1; this was compensated for when the parameter green area, calculated from plant image, was included in the model. This method reduced the time, cost, effort, and field space needed for shoot biomass evaluation compared with that needed for the sampling method, enabling shoot biomass phenotyping for a large population of plants. A total of 210 cross-populated plants were evaluated, and a correlation analysis was performed between the predicted shoot biomass and tuber yield. In addition to the prediction of tuber yield, this method could also be applied for the evaluation of crop models and stress tolerance, as well as for genetic analyses.

Preparation of biodegradable films based on modified Colombian starches from Ipomoea batatas, Manihot esculenta, Dioscorea rotundata and Zea mays

ABSTRACTThe purpose of this study was to determine the effect of different chemical modifications such as hydrolysis, esterification with docecinyl succinic anhydride (DDSA) and octenyl succinic anhydride (OSA), and acetylation with acetic anhydride on the physicochemical, morphological properties of 3 native Colombian starches selected for research (Ipomoea batatas, Manihot esculenta, Dioscorea rotundata and Zea mays) and USP Zea mays, as well as the influence on the mechanical properties of the biodegradable films prepared by the casting method. The physicochemical, mechanical and morphological properties were determined by Fourier Transform Infrared Spectroscopy (FTIR), Traction test and Scanning Electron Microscopy (SEM), respectably. The results obtained showed that the starch films modified by using DDSA were more strong and rigid, while the films modified with OSA and AA were more flexible and ductile.

Characterization of the techno-functional properties of starch from Purple yam (Dioscorea alata), Hawthorn yam (Dioscorea rotundata) and Diamante 22-type yam

This study is aimed at evaluating the techno-functional properties of starches from several yam species (Purple yam, Hawthorn yam and Diamante 22-type yam). Analytical procedures were performed according to the methods described by different authors in order to calculate waterabsorption index (WAI), water-solubility index (WSI), swelling power (SP) and syneresis. Likewise, descriptive statistics and experimental designs for interpretation of the results were also performed. The results showed that Hawthorn yam has the highest WAI (15.15 g gel/g sample, at 90°C). While WSI was similar for all species, SP is dependent on the temperature with values of 16.10 g gel/g sample (Purple yam and Hawthorn yam), and 11.25 g gel/g sample at 90°C (Diamante 22-type yam). All yam species underwent progressive reduction in syneresis, which suggests that these types of starches could be used to manufacture foods that require maintaining moisture levels.

Effect of mineral nutrition on anthracnose disease by Colletotrichum gloeosporioides Penz and rot by Botryodiplodia theobromae pat in Dioscorea rotundata variety Efuru

Effect of mineral nutrition on anthracnose disease by Colletotrichum gloeosporioides Penz and rot by Botryodiplodia theobromae pat in Dioscorea rotundata variety Efuru

Vine Cuttings Technique for Evaluating the Reaction of Dioscorea rotundata Varieties to Root-Knot Nematodes

Root-knot nematodes (Meloidogyne spp.) contribute to low productivity and post harvest losses of white yam (Dioscorea rotundata). This study evaluated yam cultivars for resistance to Meloidogyne spp. using plants generated from single node vine cuttings. Forty accessions of D. rotundata were selected for the study and laid out in a randomized complete block design with 10 plants per replicate, three replicates and two treatments (Meloidogyne-inoculated and uninoculated). Vines were planted in vertically hanging bags and inoculated four weeks after with 500 eggs of Meloidogyne spp. Plants were harvested sixteen weeks after inoculation and data were collected on weight of tubers, nematode populations in tubers and soil, and nematode damage to tubers. Vine survival was up to 60%, although inoculated vines had lower rates of survival. All the surviving vines produced tubers of various sizes which differed between the control inoculated tubers. Based on galling index (damage) and reproductive factor, five accessions were designated as resistant with the remaining accessions being susceptible. The use of vine-cuttings was found to be effective for screening yam varieties for resistance to Meloidogyne spp.

Evaluation of Cd(II) Ion Removal from Aqueous Solution by a Low-Cost Adsorbent Prepared from White Yam (Dioscorea rotundata) Waste Using Batch Sorption

An agricultural residue, white yam (Dioscorea rotundata) tuber peel (YTBS), was used for the removal of Cd(II) ion from an aqueous solution using a batch method. The adsorbent was characterized using FTIR, TGA, SEM, EDX, N2 BET, XRD, and XRF. The optimization of sorption variables such as pH, contact time, adsorbent dose, and initial metal ion concentration at 25 °C were also carried out. The results indicated the dependence of sorption on the adsorbate pH and adsorbent dose, while the adsorption system reached equilibrium in 180 min. The sorption kinetics was fitted to three models (pseudo first order, pseudo second order, and Elovich) to validate the kinetics, and the pseudo first order was the best model for the description of Cd(II) uptake. Equilibrium isotherm modelling was also carried out using the Langmuir, Freundlich, and Temkin models, with the Langmuir isotherm giving the best fitting to the experimental results. The maximum loading capacity (qmax) of the adsorbent for Cd(II) obtained from the Langmuir isotherm model was 22.4 mg∙g−1 with an isotherm constant (KL) of 3.46 × 10−3 L·mg−1 and r2 value of 0.99. This result indicates that the YTBS residue was a good adsorbent for the removal of Cd(II) ion from aqueous system.

Optimisation of the Processing Conditions on the Culinary Qualities of Pressure-Cooked Boiled Yam

ABSTRACTYam (Dioscorea rotundata) is consumed in various ways. Boiled yam, in particular, has various culinary applications in Africa, but its preparation by conventional cooking consumes time and energy. Pressure cooking offered suitable alternatives but requires careful management of cooking conditions to assure quality. This study optimised cooking condition [thickness of yam slices (1–12 cm), cooking time (5−60 min) and post-cooking resident time (2−15 min)] for the pressure boiling of yam slices on their culinary (texture and absorbed water) and sensory (appearance, texture and taste) qualities. Response surface methodology was used for the study with the aid of the Design Expert Software. Data comparing the proximate and colour qualities of the boiled yam from conventional and pressure-cooked samples was also analysed using Independent sample t-test. Boiled yam produced at verified optimisation solution (3.09 cm, 15.58 min and 3.10 min) compared favourably with that produced by conventional methods as there were no significant (p < 0.05) difference in proximate composition (t = 0.003, df = 12, p = 0.4985, 1-tailed) and colour quality (t = 0.003, df = 12, p = 0.4895, 1-tailed) of pressure-cooked and conventionally cooked boiled yam samples.

Proximate Content, Phenol and Mineral Fertilizer Effects on Infection and Weight Loss in Dioscorea Rotundata (Three Varieties) and D. Alata) (One Variety) Incubated with Botryodiplodia Theobromae

Proximate Content, Phenol and Mineral Fertilizer Effects on Infection and Weight Loss in Dioscorea Rotundata (Three Varieties) and D. Alata) (One Variety) Incubated with Botryodiplodia Theobromae

Physicochemical and Structural Characterization of Yam (&lt;sup&gt;Dioscorea rotundata&lt;/em&gt;) Mucilage

The objective of the present study was to characterize physicochemical and structural mucilage of yam ( Dioscorea rotundata ). The extraction of the mucilage was done by the continuous bubbling method, whose basis is flotation, then proximal composition, physicochemical properties (pH, acidity, dietary fiber, starch content and color) and structural characteristics (differential scanning calorimetry, Infrared spectroscopy and thermogravimetric analysis). The proximal composition shows that the yam mucilage is a product with high protein content (27.18), minerals (18.94%) and low lipid content (1.06%), it shows physicochemical properties such as pH (6.63), acidity (0.52%) and starch content (3.99%) low average values, a high brightness percentage (L* = 82.37), a high dietary fiber content (9.73%), a glass transition of 118.29°C with a multi-stage decomposition that allows its use up to temperatures below 220°C and has as its characteristic trademark a stretching C = O present in the peptide bond R-CO-N corresponding to the amide group, all these results reflect that the yam mucilage can be used in food matrices with potentialities as a functional ingredient.

Functional and Rheological Properties of Yam (&lt;em&gt;Dioscorea rotundata&lt;/em&gt;) Mucilage

The objective of the present study was to evaluate the functional and rheological properties of mucilage of Hawthorne bread of yam ( Dioscorea rotundata ). The extraction of mucilage was performed by continuous bubbling method and then its functional (solubility at 30 to 70°C, water absorption index, water solubility index, swelling capacity, stability and clarity of the paste, oil absorption capacity, emulsifier activity, stability of emulsion, total phenols and antioxidant capacity) and rheological (stationary test and viscoamilogram) properties were evaluated. The results indicate a greater solubility (96.96% to 30°C and 88.76% to 70°C) and stability of emulsion (68.89%); however, total phenol content and antioxidant capacity lower to other mucilage, possibly due to the extraction method employed (bubbling). The method that best represented the rheological behavior of suspensions of mucilage of yam was that of Oswald de Waele, categorizing it as dilatant fluid (n>1) and the viscoamilogram demonstrates the low starch content in mucilage, showing a setback of 11.43 mPa.s, which indicates high stability of this polymer. The functional properties show the potential of mucilage as emulsifier and its easy inclusion in food matrices.

Antinutritional Factors the ‘Biomolecules’ Mediated Natural and Induced Host Defence in Food Crops

Tuber crops is one of the major food crops which provide food to millions of people around the globe. Especially the tropical tuber crops viz. cassava ( Manihot esculenta Crantz), sweet potato ( Ipomoea batatas L.), taro ( colocasia esculenta L.), yams ( Dioscorea alata, Dioscorea rotundata and Dioscorea esculenta ) and chinese potato ( Solenostemon rotundifolius ) are now getting worldwide importance as economical source of energy. Tubers of all these crops are also rich in vitamins and minerals and can be a good source of dietary supplement. Leaves rich in protein, vitamins and minerals are used as fodder.

Effects of Sesame Seed Enrichment on Physico-Chemical and Nutritional Characteristics of Flour from Two Cultivars of White Yam (Dioscorea rotundata Poir)

Effects of Sesame Seed Enrichment on Physico-Chemical and Nutritional Characteristics of Flour from Two Cultivars of White Yam (Dioscorea rotundata Poir)

A comparative assessment of nutrients and anti-nutrients contents of varieties of fried yam (&lt;i&gt;Dioscorea specie&lt;/i&gt;) commonly consumed in Nigeria

There is limited information on nutrients composition of Nigerian foods. As a result, nutrients intake from Nigerian foods is in most cases estimated using foreign food composition tables. This research determined and compared proximate composition, minerals and anti-nutrients in pre- boiled fried New and old White Yam ( Dioscorea rotundata ), Water Yam ( Dioscorea alata ) and Yellow Yam ( Dioscorea cayenensis ) purchased at Yankura market, Kano, Northwestern Nigeria. Samples were peeled, boiled and fried. Fried yam samples were analysed for moisture, protein, carbohydrate, fat, ash, fiber and mineral contents using methods of the Association of Official Analytical Chemist. Phytate and cyanide were estimated bytitration. Results were analyzed using ANOVA in GraphPad Instat software. New White Yam exhibited significantly (P<0.05) higher content in moisture (52.5 ± 8.40 g/100g), fiber (2.0 ± 0.02 g/100g), calcium (13.7 ± 0.5 mg/100g); lower concentration of phytate (11.3 ± 0.08 mg/kg) and moderate concentrations of other parameters studied. Water yam contains significantly (P<0.05) higher protein (5.77 ± 0.2 %), potassium (683 ± 3.6 mg/100g) and moderate amount of other parameters studied. Yellow Yam contains significantly (P<0.05) higher magnesium (16.3 ± 1.52 mg/100g), phytate (31.2 ± 0.40 mg), lower fiber (0.9 ± 0.03 g/100g) and moderate amount of other parameters. Old White Yam contains significantly (P<0.05) higher carbohydrate (37.47 ± 0.5 g/100g), lower cyanide (3.2 ± 0.15 mg/kg) and moderate amount of other parameters studied. The fried yam samples studied have variable amount of nutrients and anti-nutrients. Apart from being excellent energy sources, all yam samples studied could contribute to intake of micronutrients. Keywords: Fried yam, proximate content, micronutrients, anti-nutrients

A comparative study of using a wooden storage box and storage platform for white yam tuber storage

The study was undertaken to evaluate the performances of an experimental box and platform, as storage structures for white yam tubers (Dioscorea rotundata Poir.). The criteria used for evaluation were the degree of mass loss during storage, tuber sprouting and rotting during the 20 weeks storageperiod: March - June 2015. Measurements of temperatures and relative humidity of the storage environment were taken three times daily during the period. Mass loss in each tuber was measured weekly while sprouts were removed from tubers weekly. Results show that the average temperature and relative humidity in the experimental box were 29.7 °C and 78.6 % respectively, while for the platform, they were 30.7 °C and 76.5 %., respectively. Rotting was completely absent on tubers in both storage approaches. White yam tubers stored in the box exhibited a cumulative mass loss of 9 %, while on the platform, it was15.0 %. The experimental box performed better in respect to mass loss and nutritional composition.

Analysis of Yam Minisett technique adoption in Nigeria

ABSTRACTWhite yam (Dioscorea rotundata Poir.) is an important tuber crop grown throughout West Africa, the Caribbean, and Latin America. Propagation of the crop is primarily vegetative, through the use of small whole tubers (seed yams) and cut pieces of tuber (setts) planted to produce the larger tubers (ware yams) that households consume and sell. The Yam Minisett Technique (YMT) was introduced in Nigeria in the late 1970s as a means of increasing the production of seed yams. The YMT is different from many other agricultural technologies in that it requires farmers to do something – cut their tubers into small pieces – which they feel based on experience is potentially damaging as it causes rot. Indeed, the existing literature suggests that adoption of the YMT tends to be low and variable. However, to date there has been no systematic analysis of the existing literature on YMT adoption designed to explore which factors are reported to be the most important and why. Hence, the objective of this paper is to analyze the YMT adoption studies published to date to explore which factors are particularly important, and how this may help guide future research in YMT adoption. The results suggest that uncertainty – risk and ambiguity aversion – as perceived by farmers is a key consideration in YMT adoption and needs to be considered in future work.

Carotenoid profiling of yams: Clarity, comparisons and diversity

Screening carotenoids of elite accessions of yam (Dioscorea spp.) used in the global yam breeding program has been conducted to quantitatively determine the carotenoid composition of the crop. Comparisons to previous data reporting cerotenoid levels in yam has been made, in order to deduce greater perspectives across multiple studies. Characterisation of complex species and accession -specific profiles have shown a rich base of diversity that can inform breeding strategies. Key findings include; (i) the identification of accessions rich in β-carotene which can aid provitamin A biofortification, (ii) Data disputing the commonly held belief that yellow Guinea yam (D. cayennensis) has higher β-carotene content than that of white Guinea yam (D. rotundata), and (iii) the tentative identification of C25-epoxy-apocarotenoid persicaxanthin with potential implications for tuber dormancy.