White Genotypes Research Articles

CALLUS INDUCTION AND MORPHOGENESIS IN <i>DIOSCOREA DUMETORUM</i> FOR STEROID PRODUCTION

Diosgenin is characteristic of the genus Dioscorea (Dioscoreaceae), which is used in partial synthesis of steroid drugs. It was not detected in the crude sapogenin extract of Dioscorea dumetorum and in the calluses. Callus was induced from the meristem of the two genotypes and maintained successfully on Murashige and Skoog's medium (MS) supplemented with 0.1mg/l of 2, 4-dichlorophenoxyacetic acid (2,4-D). Shoots induced from nodal cuttings of the white and yellow genotypes regenerated plantlets, which were subsequently maintained on MS medium, and Linsmaier and Skoog's medium (LS) supplemented with 0.5mg/l kinetin. Control of microbial contamination was achieved with tetracycline. Microtubers were also obtained from the yellow genotype plantlet growing on the MS medium. Steroids, especially the Δ 5 , 3-hydroxy steroids were detected only in the yellow genotype callus. Keywords : Dioscorea dumetorum; diosgenin; 3-hydroxy steroids; callus; shoot culture; meristem culture; yellow genotype Nigerian Journal of Natural Products and Medicine Vol.7 2003: 5-8

DNA fingerprinting studies in coloured cotton genotypes

AbstractA collection of 11 coloured cotton Gossypium hirsutum genotypes and four white linted genotypes of different origin were evaluated by randomly amplified polymorphic DNA (RAPD) analysis. These 15 cotton genotypes were evaluated using 32 different 10‐mer primers of arbitrary sequences. All 32 primers were polymorphic ‐ in total, 287 amplified fragments were observed in these patterns. Out of the 287 fragments, 219 were polymorphic accounting for 76.31% of the total number of fragments. Similarity indices were calculated using the Dice coefficient and a dendrogram showing relationships between genotypes was obtained by Unweighted Pair Group Method of Arithmetic Average (UPGMA) cluster analysis. Cluster analysis showed clear‐cut separation of the coloured and white linted genotypes and thus formed three clusters (I, II and III). Among the coloured linted genotypes, all except ‘Parbhani American’ and ‘Lousiana brown’ clustered together. Cluster II contained white linted genotypes orginating from the same breeding station. The results indicate that RAPDs may constitute a relatively simple and efficient method for analysing genetic variation in coloured and white linted G. hirsutum collections.

Substrate suitability of different genotypes of sorghum in relation to Aspergillus infection and aflatoxin production.

Grain sorghum is often damaged by rain in the field and severely infected by grain mold, which includes Aspergillus infection and aflatoxin production. The objective of the study is to investigate the extent of aflatoxin production with Aspergillus infection in vitro in different sorghum genotypes with different pericarps, red, yellow, and white, the physical and chemical characteristics of grain during infection, and the changes in grain polyphenols and phytic acid in comparison to maize and groundnut. The physical characters and biochemical composition of sorghum grain contribute to make it less susceptible to Aspergillus infection and aflatoxin contamination compared to maize and groundnut. The lowest amounts of aflatoxin and ergosterol were observed in genotypes with red pericarp, whereas higher amounts of aflatoxin and ergosterol were found in white genotypes followed by maize and groundnut. All of the red genotypes differ in polyphenol composition and aflatoxin produced, showing resistance to mold damage. Another indication of resistance in red genotypes was the delayed peaking of aflatoxin production (9 days after infection). In red sorghum genotypes there was a significant, positive correlation existing between polyphenol content and aflatoxin produced at 3 and 6 days after infection, the r values being 0.589 and 0.513, respectively. The starch content decreased whereas the protein content in all sorghum genotypes increased during infection. Maximum phytic acid was observed in white sorghum genotypes. Phytic acid in yellow genotypes was found to have a significant negative correlation (r = -0.569) with aflatoxin produced.

Genetic Variability in the Fodder Yield, Chemical Composition and Disappearance of Nutrients in Brown Midrib and White Midrib Sorghum Genotypes

Samples of eleven brown midrib (ICSU 96031, ICSU 93046, ICSU 96082, ICSU 96078, ICSU 96075, ICSU 95101, ICSU 96034, ICSU 96063, ICSU 45116, ICSA 93-3 and ICSA 3845 X 3816) and nine white midrib genotypes (ICSU 96050, ICSU 96030, ISU 95082, SSG 59-3, FSHI 93-1, FSHI 2219A X 3211, HC 171, ICSA 93-2 and ICSA 93-1) based on their phenotypic appearance were collected at 50 per cent flowering from the sorghum germplasm grown at Research farm of IGFRI, Jhansi. These genotypes were evaluated with respect to crude protein, fiber composition, in-sacco dry matter, OM, cell wall components disappearance/digestibility besides the fodder yield, total phenolic and availability index values. Brown midrib genotypes were lower (p 0.05) differences were observed in dry matter, crude protein and organic matter contents between brown midrib and white midrib genotypes. Phenolic contents were significantly (p 0.05) differences between genotypes in extent of fiber fraction degradability though in-sacco NDF and ADF degradability was more by 5 and 4 units, respectively in brown midrib genotypes vis-a-vis white midrib genotypes. Average fodder yield (green and dry g/plant) and availability index (%) values were significantly (p<0.05) higher for brown midrib (474.2, 129.8 and 80.4) genotypes than white midrib (375.0, 104.8 and 69.2) genotypes. Lignin contents had significant negative correlation with DM, OM, NDF and ADF degradability. The results of the study revealed that brown midrib genotypes are superior not only with regard to chemical entities and disappearance of DM and fiber fractions but also better in respect of fodder yield and availability index values. Thus, brown midrib sorghum strains may be useful in increasing digestibility, intake, feed efficiency and animal performance. (Asian-Aust. J. Anim. Sci. 2003. Vol 16, No. 9 : 1303-1308)

Southeast Asian patients with chronic hepatitis C: The impact of novel genotypes and race on treatment outcome

Hepatitis C virus (HCV) genotype and other host and viral factors influence treatment outcome in chronic HCV infection. We evaluated the effect of race and genotype on interferon and ribavirin treatment outcome in 70 Southeast Asian (SEA) and 50 white patients. Genotype was based on the 5' untranslated region (5'UTR) with a commonly used line probe assay (INNO-LiPA HCV II) that may mistype genotype 7, 8, or 9 as 1b. HCV core region sequencing resulted in reclassification of 8 genotype 1 and 25 genotype 1b SEA subjects as genotype 7, 8, or 9. Twenty-six SEA genotype 7, 8, and 9 (79%) and 10 SEA true genotype 1b (59%) patients achieved a sustained virologic response (SVR) compared with 15 (34%) white genotype 1b patients. Logistic regression analysis showed that SEA patients with genotype 7, 8, or 9 were more likely to achieve a SVR than white genotype 1b patients (OR 16.56; 95%CI 4.16, 65.91) as were SEA true genotype 1b patients compared with white genotype 1b patients (OR 4.63; 95%CI 1.19, 18.04). In conclusion, a proportion of SEA patients classified by INNO-LiPA as genotype 1b were in reality genotype 7, 8, or 9. In comparison with white genotype 1b patients, both SEA genotype 1b and SEA genotype 7, 8, and 9 patients showed a significantly greater SVR. HCV core sequencing was necessary to determine genotype accurately in persons potentially exposed to HCV genotypes 7, 8, or 9. This study also supports the concept that race and ethnicity are important determinants of treatment outcome in HCV infected patients.(H EPATOLOGY 2002;36:1259-1265.)

The relationships between plasma glucose and insulin concentrations, and growth performance in German Pietrain and Large White porcine genotypes

Insulin is a central regulatory factor in the control of nutrient partitioning during growth and development. It has been demonstrated that the rate of protein deposition is elevated in porcine muscle following insulin infusion (WrayCahen 1998), and that the degree of adiposity is positively associated with plasma insulin concentration (Wood et al., 1977; Polonsky 1995). The objective of the study was to examine the effect of plasma glucose and insulin concentrations on growth performance in two porcine genotypes.

Changes in enzyme activities and aflatoxin elaboration in sorghum genotypes followingAspergillus parasiticus infestation

Sorghum is a relatively poor substrate for aflatoxin production compared with high-risk agricultural commodities like maize and groundnut, even though it is susceptible to fungal attack. Fungal infestation of sorghum results in a varied biochemical composition of the deteriorated grain. In this study, six sorghum genotypes (red—AON 486, IS 620; yellow—LPJ, IS 17 779; white—SPV 86, SPV 462) were inoculated with a toxigenic strain of Aspergillus parasiticus (NRRL 2999) in order to evaluate the changes in the activities of various hydrolytic enzymes (α- and β-amylases, protease and lipase) in comparison with those in uninfected grains. Enzyme activities were measured at different times after fungal infestation, and the enzymatic activities were correlated with the aflatoxin production. Alpha-amylase activity was observed to be greater than β-amylase activity in all six genotypes under both healthy and infected conditions. The increase in α-amylase activity during the period of infection was higher in white genotypes than in red sorghum genotypes. Alpha-amylase activity in all the genotypes increased up to day 6 after fungal infection, but was significantly lower in infected grains than in healthy grains. The variability in the basal enzyme activities among the six sorghum genotypes was quite high compared with the amount of induction of each specific enzyme due to infection and germination. Higher protease activity was observed in the infected grains than in healthy grains. The enzyme activities in high tannin red genotypes were less than those in yellow and white genotypes. The α- and β-amylase activities were positively correlated (r = 0.406 and 0.436; P < 0.05) to aflatoxin production. Inherent lipase activity was highest (on day 0) in AON 486, SPV 462 and SPV 86, as compared with the activity in infected grains. The total aflatoxins produced (quantified by TLC-fluorodensitometry) were lower in red genotypes than in yellow and white genotypes, suggesting that red genotypes were least susceptible to aflatoxin elaboration among the various genotypes tested. All four aflatoxins, (B1, B2, G1 and G2) were present in five genotypes (IS 620, LPJ, IS 17 779, SPV 86 and SPV 462) at all the stages of infection, but, aflatoxin could not be detected in the red genotype AON 486 on day 3 after infection. White genotypes SPV 86 and SPV 462) showed maximal aflatoxin (total) production on day 6 after infection. © 2000 Society of Chemical Industry

Response of white clover genotypes to evaluation environments of dense and spaced planting, and implications for selection

Twelve genotypes were grown for two years asmonocultures in the evaluation environments (EE) ofspaced planting (SP) and dense planting (DP). Drymatter (DM) yield, seed yield and their contributingtraits were recorded. The environments were comparedfor: i) genotype performance, and selection efficiencyfor the target environment of DP, and ii) estimates ofgenetic correlations between traits. DP was obtainedby close transplanting of clonal cuttings. EE × Ginteraction occurred for DM yield over harvests, andstolon density, petiole length, inflorescenceproduction and number of florets per inflorescence averagedover repeated measurements. Interaction effectsleading to relatively higher DM yield in SP tended tobe associated positively with those for the othertraits and featured the genotypes with greater abilityto colonize bare soil by stolon production. Theinteraction effects decreased with time and generallydisappeared (p < 0.05) by the end of the experiment,when the environments reached a similar DM yield andstolon density. EE × G interaction also occurred forseed yield (p < 0.08), recorded at the second year.Indirect selection in SP for performance in DP waspredicted to be less efficient for DM yield (–40%),seed yield (–23%) and the other traits subject to EE ×G interaction, compared with direct selection in DP.Evaluation under SP led to identification of severalgenetic correlations that were not confirmed under DP.DP compared with the traditional SP evaluationtechnique is more labour-demanding but allows for i)increasing the selection efficiency and/or decreasingthe time needed for a reliable evaluation, and ii)obtaining a more reliable estimation of geneticcorrelations for ordinary agricultural environments.

Meat quality of Large White pig genotypes selected for components of efficient lean growth rate

AbstractResponses in carcass composition and meat quality after seven generations of selection for components of lean growth rate were examined in a population of Large White pigs. There were four selection groups in the study, with divergent selection for lean growth rate on ad libitum (LGA) or restricted (LGS) feeding regimes, lean food conversion ratio (LFC) and daily food intake (DFI). In generations six and seven, two offspring from each of 10 sires, within each selection line, were to be allocated for half-carcass dissection and measurement of meat quality. There were 320 animals in the study, with 40 animals from each of the high and low selection lines and, within each selection line, two offspring per sire.Responses in carcass composition were similar in the three selection groups given food ad libitum, but rates of lean and fat growth rate differed between selection lines. Intramuscular fat content was reduced with selection for high LGA and high LFC but was increased with selection for low DFI (-1·7 and -3·2 v. 2·7 (s.e.d. 0·7) mg/g), which was unexpected given the higher carcass fat content of the low DFI line, relative to the high line (249 v. 190 (s.e.d. 7) g/kg). Muscle colour was darker, as measured by trained sensory panel assessment, in selection lines which reduced the rate of fat deposition to achieve a leaner carcass (high LFC and low DFI) but there was no response in muscle colour with selection for LGA (0·4 and 0·3 v. 0·0 (s.e.d. 0·1)). Responses in muscle shear force (5·3 v. 4·4 (s.e.d. 0·4) kg) and flavour liking (4·0 v. 4·3 (s.e.d. 0·12)) were limited to the LGA and LFC selection groups, respectively. There were no significant responses in muscle moisture content, muscle pH or myofibrillar fragmentation index, nor were there any responses in meat quality with selection on LGS. Therefore, decreasing the rate of fat deposition was associated with darker meat and increasing the rate of lean growth was associated with higher shear force. There were selection strategy specific responses in the fatty acid composition of intramuscular fat, which may have contributed to the responses in eating quality.In general, responses in meat quality were small, such that incorporation of meat quality traits in selection objectives, which are primarily focused on increasing the efficiency of lean meat production, may not be necessary. However, it would be pertinent to evaluate periodically genotypes of breeding companies for muscle quality traits.

Response of white clover genotypes to intergenotypic and interspecific interference

Six white clover genotypes that were easily distinguishable from each other on the basis of leaf lamina marks and morphology were grown at Lodi, Italy, during 1990 and 1991 in dense swards, under field conditions and a mowing regime, as (i) pure stands, (ii) a complex mixture of all genotypes, (iii) binary mixtures of each genotype with each of two ryegrass varieties, and (iv) complex mixtures of all clover genotypes in binary association with each grass variety. The grass components were of known, different vigour. The study assessed both intergenotypic and interspecific interference and related dry matter yield responses to morpho-physiological traits of the clovers, and also determined whether a high level of morpho-physiological heterogeneity conferred a yield advantage on clover populations.Greater heterogeneity (i.e. a complex mixture of clover genotypes) did not produce higher clover yields either in the presence or absence of interspecific interference from grass; thus, the use of blends of varieties or the development of varieties with a fairly high degree of heterogeneity was not recommended for short-term meadows in environments with relatively low spatial and temporal variability. Interactions for yield occurred between clover genotypes and the presence or absence of intergenotypic interference (P&lt;0·001), and between clover genotypes and the presence or absence of interspecific interference from the grass variety characterized by greater vigour and aggressiveness (P&lt;0·01). The variance of the former interaction tended to be consistently larger than that of the latter interaction, indicating that competitive effects were greater between clovers than between the clover and grass components. A lower Spring [ratio ] Summer yield ratio and taller canopy tended to confer a competitive advantage under intergenotypic interference. Relatively better performance under interspecific interference was related to higher stolon density, suggesting that selection for this trait may increase the general ecological compatibility of large-leaved white clover types grown with vigorous grass companions.

Dysarthria and Apraxia of Speech Associated With FK-506(Tacrolimus)

Dysarthria and Apraxia of Speech Associated With FK-506(Tacrolimus)

Inheritance of mitochondrial DNA in interspecific crosses of Piceaglauca and Piceaomorika

Fifteen interspecific hybrids of Serbian spruce (Piceaomorika (Panc) Purkyne) and white spruce (Piceaglauca (Moench) Voss) representing five separate crosses, including reciprocals, were used to demonstrate maternal inheritance of mitochondrial DNA. Total DNA was extracted from foliage samples of Serbian spruce (S), white spruce (W), and both S(♂) × W(♀) and W(♂) × S(♀) hybrids, digested and probed with one of two maize mitochondrial genes, ATPaseα or COXII. ATPaseα generated diagnostic Serbian and white spruce genotypes for all five enzymes tested, while COXII differentiated between the two species for four of five enzymes. Maternal inheritance was indicated in all hybrids for every diagnostic enzyme–probe combination. No paternal or nonparental bands were detected. A dilution experiment indicated that the Serbian and white spruce mitochondrial DNA restriction fragment length polymorphisms could be detected in as little as 60 and 500 ng of total DNA, respectively. It appears that the mechanism that controls the inheritance of mitochondria in Picea is still functional in wide interspecific crosses.

Uptake of phosphorus from different sources by Lotus Pedunculatus and three genotypes of Trifolium Repens .1. Plant yield and phosphate efficiency

The breeding of phosphate (P) efficient pastoral legumes could reduce the amount of fertiliser required on pastoral farms. In this study, Lotus pedunculatus and 3 genotypes of white clover (Trifolium repens L.) known to differ in their ability to respond to added P were grown on unfertilised soil and soil to which either monocalcium phosphate (MCP) or North Carolina phosphate rock (NCPR) were added. White clover genotype 8D (a selection line from Crau) had a greater (P &lt; 0.05) internal P efficiency (shoot DM production per unit plant P) than 1A (a selection line from Gwenda) or lotus on unfertilised soil, whereas on fertilised soil, lotus had a significantly higher (P &lt; 0.05) internal P efficiency than 2 of the white clover genotypes on MCP-fertilised soil (P &lt; 0.01) and all 3 white clover genotypes on NCPR-fertlised soil (P &lt; 0.01). Lotus also had a higher (P &lt; 0.01) external P efficiency (total P uptake) than all 3 white clover genotypes on the 2 fertilised treatments. This was due to a greater root length, not a greater P uptake per unit length.

Phosphorus response of white clover(Trifolium repensL.) genotypes selected for tolerance of aluminium toxicity

Abstract Phosphorus (P) responses for two white clover (Trifolium repens L.) genotypes, previously selected for aluminium (Al) tolerance, were compared with those for two P‐efficient genotypes over a range of soil‐extractable Al levels. The Al‐tolerant genotypes had similar P response characteristics to the P‐efficient genotypes. One of the P‐efficient genotypes showed as much Al tolerance as the genotypes originally selected for Al tolerance. The implications for plant breeding are that it is possible to select white clover genotypes that are Al‐tolerant without increasing the need for P fertiliser.

Germination of cut seeds and seedling growth of ash (Fraxinus spp.) in vitro

Nonstratified seeds of different genotypes of Fraxinusamericana L. (white ash), Fraxinuspennsylvanica Marsh, (green ash), and Fraxinusangustifolia Vahl. ssp. oxycarpa (narrowleaf ash, of Afghanistan origin) were surface disinfested, cut, and germinated in vitro on agar-solidified MS (Murashige and Skoog) medium containing sucrose and various plant growth regulators. Before placing in vitro, approximately one-third of the seed opposite the radicular end was excised and discarded, or the apical and basal 1 mm tips of the seed were aseptically excised. Within 1 week, viable seeds germinated. Cotyledons emerged, elongated, expanded, and turned green. After 2 weeks hypocotyls and radicles elongated. White and green ash genotypes germinated at different rates; generally &gt;80% of seeds placed in vitro germinated. Genotype and the presence of thidiazuron in the medium had an effect on seedling development (hypocotyl and epicotyl elongation). Immature as well as nonstratified mature seeds germinated and grew. Epicotyls were excised, rooted, and established in the greenhouse.

Extent of Cross-pollination of One Sweet Corn Genotype onto Another in Adjacent Plantings

Recommendations for culture of sweet corn (Zea mays) suggest separation of genotypes for color and/or sweetness by considerable distance since corn is generally wind-pollinated and unwanted pollination may result in undesired color or sweetness effects. Many small-scale producers lack adequate acreage to separate plantings by more than a short distance. To determine the extent of cross-pollination, `Golden Queen' yellow sweet corn was seeded in a circular pattern of 16 rows in 1989 and eight rows in 1990. White `Silver Queen' was then planted in 20 rows around the yellow genotype. The circular pattern enabled detection of pollen carried by wind in any direction. Yellow kernels on `Silver Queen' were attributed to cross-pollination. Depending on wind speed and direction, cross-pollination ranged from 50% on adjacent rows to none as close as eight to 10 rows from the yellow type. Consumer acceptance of a white genotype with a few yellow kernels was not determined.

Interference Effects in Grass Varieties Grown as Pure Stand, Complex Mixture and Binary Mixture with White Clover

The study aimed at: i) assessing the agronomic value of the pure stand (PS), of the complex mixture (CM) and of the binary mixture with each of six white clover genotypes (MWC) of eight grass varieties belonging to four species and contrasting for earliness of flowering; and ii) investigating the relationships of competitive abilities in CM and MWC with some morpho-physiological traits of the grass varieties. CM showed a 24 % dry matter yield (DMY) advantage over mean value of PS but did not outyield the pure stand of the best yielding component. For grass-white clover associations, the DMY advantage as Relative Yield Total over PS of the components averaged 43 %. DMY of the grass varieties averaged across MWC conditions was related positively to total DMY (r = 0.99) and negatively to associated clover DMY (r = - 0.96). Competitive abilities as Relative Yield of the grass varieties in CM and in MWC correlated (r = 0.84) and were both positively associated to DMY, canopy height and inclination of leaves in PS. The results suggested that association of white clover with a grass of moderately high vigour, intermediate earliness and relatively erect leaves may provide the best option for rotational meadows in the experiment environment.

Sensory evaluation of a hard white compared to a hard red winter wheat

AbstractTraditionally bread wheats grown in the USA have been hard red genotypes. Introduction of hard white genotypes provides an opportunity for the comparison of the products and evaluation of consumer acceptance. MT 7811, a hard white wheat, and ‘Norwin’, a hard red winter wheat, were grown in adjacent plots in each of two years. Grain from each was divided, with half milled into whole wheat flour (wholemeal) and the other half milled into white flour (milled flour). Breads made from wholemeal and milled flour from each wheat genotype were tested by panelists for differences. Color differences were easily detected. The Wilcoxon‐Mann Whitney rank sums test was used to evaluate signal detection data. Both crust and crumb differences between the two wheats could be detected by some panelists. Differences could be detected between the two wheat types in either wholemeal or milled flour bread. Crust differences were often greater than crumb differences. Trained panelists commented on some bitterness in red wheat products and a sweetness in white wheat products.

Identification of gerbera cultivars based on differences in phenolic compounds in ray florets

SummaryA method is described for the identification of gerbera cultivars using HPLC-analysis of phenolic compounds from ray florets. Anthocyanins and flavonoid copigments were analyzed in 65 genotypes. Different criteria for minimum peak area (pamin = 50, 100 or 1000 mVs) and peak matching (maximum difference in peak area, pdmax = factor 2 or 10) were used. The discrimination capacity for anthocyanins ranged from 92.3% of all 2080 pairwise comparisons, using pamin = 50 and pdmax = 2, to 70.5%, using pamin = 1000, pdmax = 10. For flavonoid copigments, the discrimination capacity ranged from 98.9% (pamin = 100, pdmax = 2) to 89.9% (pamin = 100, pdmax = 10). By combining the anthocyanin data (with pamin = 50) and the copigment data (with pamin = 100), using pdmax = 2, a discrimination capacity of 99.5% was obtained. No relation was found between copigment composition and floret colour. For anthocyanins, the yellow and white genotypes formed one cluster. Generally, the reddish and pinkish/purplish genotypes w...

Variation for Preharvest Sprouting Resistance in Durum Wheat

Preharvest sprouting may reduce end‐use quality and is thus an important grading criterion in all market classes of wheat (Triticum spp.). There are few reports in the literature of genetic variation in preharvest sprouting resistance in durum wheat (T. turgidum L. var durum), and the only apparent attempts to breed sprouting resistant durums have been to transfer resistance from red common wheat (T. aestivum L.). Use of resistance sources within the durum species would be easier, so this study was undertaken to assess the variation for sprouting resistance in durum. Sprouting resistance of 185 durum genotypes was evaluated in 1990. Unreplicated samples of 10 spikes from each genotype were evaluated in an artificial rain chamber. Sixty of these genotypes were re‐evaluated in a replicated study in 1991. The 1990 study indicated that the durums had a similar range in sprouting score (spikes out of 10 showing visible sprouts) to the common wheat checks. The sprouting scores of the red (5.8 ± 3.7, n = 30) and white (6.5 ± 3.0, n = 149) genotypes were not different (P &lt; 0.05). Sprouting score measured in 1991 was correlated with that of 1990 (r = 0.55, n = 60). We conclude that there is considerable genetic variation in sprouting resistance in durum that can be more easily exploited by durum breeders than common wheat sources of resistance.