bluuebunny/crossref_metadata_2025_split huggingface dataset:
Response to Mass Selection for Plant Height and Grain Yield in Amaranth (Amaranthus spp.)
Authors: Vaidya K. R. , Jain S. K. 
Published: April 2006

AbstractTwo landrace accessions of amaranth, UCC 192 (Amaranthus cruentus) and UCH 213 (A. hypochondriacus), were used in a mass selection experiment; five per cent of the tallest and highest yielding plants in both populations were selected for three cycles. Selection gain was largest in the first cycle for both traits. Realized heritability estimates for plant height were C.22 in the UCC 192 population and 0.49 in UCH 213, and 0.09 in both populations for yield. The results supported earlier findings for the existence of genetic variability within amaranth landrace populations.
Yield, Oil Content and Fatty Acid Composition Evaluated in Androgenetic Plants in Brassica juncea
Authors: George L. , Abraham V. , Suryavanshi D. R. , Sipahimalani A. T. , Srinivasan V. T. 
Published: April 2006

AbstractHomozygous diploids were obtained through anther culture in Indian mustard, Brassier juncea, cultivar TM‐4, Seeds could be harvested from 97 such plants in the A; generation. The androgenetic lines were further selected and the yield and yield components were compared in the A4 and A5 generations, Androgenetic lines showed variations for most of the characters studied including seed oil content and fatty acid composition. However, it was possible to recover seven lines out of 25 which were equal in seed yield and three equal in oil content compared TO the anther donor parent TM‐4.
Variation in Nitrate Tolerance of Nitrogen Fixation in the Pea/Rhizobium Symbiosis
Authors: Jensen E. S. 
Published: April 2006

AbstractThe short‐term effects of nitrate on symbiotic nitrogen fixation were studied in six cultivars of pea (Pisum sativum L.) using two strains of Rhizobium leguminosarum. Plants grown symbiotically for three weeks, in order to eliminate the effect of NO3 on nodule formation, were exposed to nil, 5 or 15 mM NO3 for a period of seven days. Nodule mass, nitrogenase activity by acetylene reduction and the NO2 and NO3 concentrations in nodules were determined.Exposure to nitrate reduced the total acetylene reduction activity (ARA) in all cultivars, and a significant cultivar × nitrate treatment interaction was found. Nitrate influenced the components of N2 fixation, nodule mass and specific ARA (ARA/mg nodule), differently within and among cultivars. Nodule mass was reduced in all cultivars, but a variation among cultivars in the degree of reduction was found. Nitrate also reduced the specific ARA to different extents in the cultivars‐ The specific ARA of nodules from NO3‐treated plants, expressed as per cent of the specific ARA of nodules from plants grown without NOT3 was negatively correlated with the concentration of NO3 in nodules. No relationship was found between the reduction of N2 fixation and the nitrite concentration in nodules.The results indicate that it is possible to improve the nitrate tolerance of symbiotic N2 fixation of the established pea/Rhizobium symbiosis by selection of suitable host plants.
Production and Cytogenetical Analysis of a Rye‐Cytoplasmic Tetraploid Triticale
Authors: Melz G. , Schlegel R. 
Published: April 2006

AbstractA rye‐cytoplasmic tetraploid triticale was found in Fs progenies of crosses between tetraploid rye‘No 1323’and hexaploid triticale‘KT 77′. In the tetraploid triticale, two complete rye genomes and two mixed wheat genomes, consisting of the chromosomes 1A. 2A, 4A, 7A, 3B, 5B, and 6B are present. The rye cytoplasm did not affect stability of rye chromosome pairing during metaphase 1, since rye chromosomes participated in pairing irregularities just as did wheat chramosomes, even on a larger scale. The fertility of F0, plants ranged from 0 to 75.6 %, always associated with high grain shrivelling. The analyzed pairing behaviour of induced triploid hybrids from crosses between the tetraploid triticale and diploid rye indicates the presence of at least one wheat‐rye translocation in one of the investigated triploid plants.
Callus Culture‐Derived Somaclonal Variation in the Tropical Pasture Legume Stylosanthes guianensis (Aubl.) Sw.
Authors: Godwins I. D. , Gordon G. H. , Cameron D. F. 
Published: April 2006

AbstractPlants were regenerated from leaf‐derived callus cultures of five genotypes of Stylosanthes guianensis. There were substantial genotypic differences in morphogenetic potential, ranging from 95–100 % of cv.‘Graham' calh to less than 1% of cv,‘Oxley' calh forming shoots. A total of 1024 regenerants (SC1) were planted out, with 28.1 % surviving to set seed. Variant characters including albinism, reduced fertility, dwarfism and leaf morphology were observed. Variation in selfed progeny (SQ2) of 138 SC1 plants was assessed in a replicated field trial involving 2484 SO2 individuals. Variant phenotypes were observed in 55 (39.9 %) SC2 families. Many families were segregating for albinism, altered morphology or reduced fertility. Thirty families had lower yields than their parent and earlier and later flowering variants were found. Eight tetraploid families were identified. These were characterized by more erect habit, larger leaves, stems, flowers and seeds, reduced fertility and yield and a tendency to flower later.
Dihaploid Plant Production from 4 × ‐Genotypes of Potato by the Use of Efficient Anther Plants Producing Tetraploid Strains (4 × EAPP‐Clones) — Proposal of a Breeding Methodology
Authors: Uhrig H. , Salamini F. 
Published: April 2006

AbstractTetraploid clones of potato with a superior efficiency in producing androgenetic plants (4 × EAPP‐clones) have been obtained by culturing in vitro anthers of 2 × EAPP‐clones. The latter were isolated by three cycles of recurrent selection from diploid breeding material (UHRIG 1985 a). In this paper we report on the capacity of 4 × EAPP‐clones, when crossed to in vitro unresponsive 4 × genotypes, to transmit to their F1 their androgenetic potential, Five 4 ×× 4 × F1 crosses were considered, which produced on average 35 embryoids per flower – a value higher than that of nonresponsive 4 × genotypes (no embryoids obtained), but‐also significantly better than the value found for 4× EAPP‐clones (9.8 embryoids per flower). The hybrid families behaved differently from each other, with one producing up to 63 embryoids per flower. A range of per plant values was, moreover, found, revealing the existence of a large variability among sister plants belonging to the same F1 cross. The presented data indicate a rather simple inheritance of dominant genetic factors acting in favor ot androgenesis. They also suggest that the utilized 4× EAPP‐clones were possibly heterozygous for such genes.Data are also reported on the ploidy level of anther plants obtained from 4× and 2× EAPP‐clones. In this respect 2× EAPP‐clones show the interesting capacity of generating, via anther culture, a consistent fraction of tetraploid plants (13,7 %).Based on the findings reported in this paper we propose, for tetraploid S. tuherosum L., a cyclic breeding procedure making use of anther culture and where ploidy level alternates, within a cycle, between 2× and 4×.
The EEC Barley and Malt Committee Index for the Evaluation of Malting Quality in Barley and its Use in Breeding
Authors: Molina‐Cano J. L. 
Published: April 2006

AbstractA new statistical quality index, Q, is defined in order to facilitate the interpretation of the overall quality of malting barley varieties. Q ranges from O (feeding barley) to 9 (top quality malting barley), and is related to the Normal distribution. The varieties tested within the network of the European Brewery Convention are assessed for malting quality as an example of tire reliability of Q. In addition, the new index is used to study the genotype X environmental interaction for malting quality.
Cytogenetic Investigations in Wheat, Rye and Triticale
Authors: Hesmann C. U. , Pfeifer‐Schad B. , Martin J. 
Published: April 2006

AbstractIn two rye cultivars and four inbred lines, derived from two different source populations, the extent of polymorphism in the distribution of constitutive heterochromatin was investigated by means of the Giemsa C‐banding method. Between the source populations only slight differences appeared, therefore a close relationship has to be assumed. Within open‐pollinated cultivars a wide range of variation was found not only for telomeric, but also for interstitial chromosomal bands. Even intracellular polymorphism between homologous chromosomes was observed frequently in cultivars. On the other hand, polymorphism was detected in the lines to a small extent only.Inbred lines show a higher number of constant Interstitial bands than cultivars. In the latter there exist different variants of a certain band, but only one of these variants is manifested in an inbred line drawn from the same source population.Whether this manifestation takes place randomly, or low heterochromatin variants arc preferred, is discussed with regard to the problems of triticale breeding.
The Cytological Status of Plants Regenerated from Shoot‐Meristem Culture of Pisum sativum L
Authors: Ahmed Rina , Gupta S. Dutta , Ghosh P. D. 
Published: April 2006

AbstractThe cytological status of plantlets regenerated from shoot apical meristems of Pisum sativum was investigated. Chromosome counts in root apices of in vitro regenerated plants showed a preponderance of diploid cells. Moreover, the karyotypes of root‐tips from plants derived from culture and from normal plants were basically the same. Topics such as the treatment of chromosomal armlength data, simple statistical comparison of samples derived from normal and regenerated plants are discussed.
Studies on Intergenotypic Competition in a Wheat Multiline Using Alternative Row Design
Authors: Prakish K. S. , Gautum P. L. , Rao B. P. 
Published: April 2006

AbstractDifferences between the isolines in a multiline may result in differences in competitive ability and lead to changes in the frequency of the components after a few cycles of multiplication. Alternative‐row design of Hanson et al. (1961) was used to detect and characterize the presence of intergenotypic interactions among eight isolines of a multiline of bread‐wheat‘Kalyansona’. The material was grown in 1.5 meter row plots using a unique sequence of arrangement. The observations were recorded with respect to plant height and grain yield per plan:. The results of the analysis showed the components of variance for average competitive ability and specific combination to be highly significant, indicating the existence of intergenotypic interactions. Significant genotypic differences between isolines revealed that the genotype of the recurrent parent had not been fully reconstituted. On the basis of the effect of the border genotype averaged over all the genotypes (Ck.), the genotypes were classified into four groups, viz. a) highly depressive, b) mildly depressive, c) mildly cooperative and d) highly cooperative. Categories c and d were indicated as useful for the synthesis of multilines.
Field Performance of Androgenetic Doubled Haploid Spring Wheat Lines in Comparison with Lines Selected by the Pedigree System
Authors: Winzeler H. , Schmidand J. , Fried P. M. 
Published: April 2006

AbstractA total of 316 doubled haploid lines (DH) of spring wheat were compared with 621 lines selected in a pedigree system (PS) under field conditions in a breeding nursery. The lines originated from 21 crosses and the samples tested represent mean values for variables comprising the main breeding goals such as disease resistance, baking quality, and agronomic traits. In general, the DH lines were later in days to heading and shorter than PS lines of different homozygosity levels. Except for leaf rust (Puccinia recondite), the DHs were more resistant to the artificially infected diseases such as powdery mildew (Erysiphe graminis), stripe rust (Puccinia striiformis), and septoria nodorum blotch (Septoria nodorum). These differences, which were relatively small for practical selection purposes, were probably due to easier and more precise disease assessment of the homozygous DH lines. For quality characters, the DHs had a higher protein level, while the rest of the parameters were similar for both origins.The data analyzed suggest so far that androgentic doubled haploids in spring wheat are very similar to lines selected in a pedigree system in respect to all the agronomic characters tested. However, the DH lines were produced in a much shorter period of time. It is suggested that androgenetic doubled haploids be produced from F1 hybrids and that the well‐established bulk method should continue to allow selection bulk method should continue to allow selection for rare recombinants as soon as homozygosity is reached.
Genetics of Resistance in Vicia sativa L. to Orobanche crenata Forsk.
Authors: Gil J. , Martin L. M. , Cubero J. I. 
Published: April 2006

AbstractThe genetics of resistance of common vetch (Vicia sativa L.) to broomrape (Orobanche crenata Forsk.) was studied for two years by using the P1, P2, F1, BC1, BC2, F2 F3, and F4 generations obtained from crosses between resistant and susceptible lines. Resistant lines were selected by screening a world collection m a naturally infested plot. Resistance was tested both under field and greenhouse conditions. The best index to measure resistance was the number of emerged broomrapes per host plant. The results fit the additive‐dominance model. The main component of the variation was additivity; dominance and interaction effects seemed to depend on the environment. When dominance is expressed, a low number is dominant over a high number of broomrapes per host plant.
Doubled Haploids of Cocoa (Theobroma cacao L.) 1. Observations of Fertility
Authors: Lanaud C. 
Published: April 2006

AbstractOvule and pollen fertility have been studied in doubled haploids of cocoa derived from spontaneous haploids, doubled by colchicine treatment. The two measures of fertility were very variable; occasionally, the levels were as high as those of the parent plant, but most were lower. The low fertility was not improved either by changing pollinators or after grafting. Pollen fertility also varied seasonally more in doubled haploids than in their parents.The lack of differentiation of embryo sacs seemed to be the cause of low values of ovule fertility. Both of these unfavourable characteristics were not observed in the progeny of doubled haploids, The low fertility is described in terms of homozygote depression, forced, on normally allogamous plants, its consequences for the use of doubled haploids in the production of hybrid seeds are discussed.
Effects of Competition upon the Productivity of White Clover‐Perennial Ryegrass Mixtures. Seasonal Trends
Authors: Hill J. , Michaelson‐Yeates T. P. T. 
Published: April 2006

AbstractSeasonal trends among those characters, affecting productivity in white clover‐perennial ryegrass mixtures were investigated m a set of 20 mixtures using clover material derived from a. diallel cross between four contrasting white clover varieties. The productivity and associated vegetative characters showed the familiar pattern of high grass production in spring, and early summer, with a secondary peak of growth in autumn, whilst clover achieved its; highest productivity levels in mid‐summer. A significant linear relationship was established between clover canopy height and ryegrass canopy height for all 20 mixtures. Although no significant heterogeneity was detected among the fitted regression lines, there was an indication that the linear regressions provided a better fit to the data in those mixtures having ‘Skomer’ as the grass companion. An analysis of the differences in canopy height between ryegrass and clover indicated that the ‘Menna ‘/’S. 23’ mixture had a reduced seasonal range compared to the other mixtures. Consequently, during the early par', of the growing season, when the tallest canopies occurred and. when shading of clover by the grass was most intense, the difference in canopy height between ‘S. 23’ and ‘Menna’ was relatively low. There was a pronounced effect of grass companion upon canopy height difference, due entirely to the taller growth habit of the ‘Skomer’ ryegrass variety, These interrelationships are discussed briefly in the context of improving the productivity of white clover‐perennial ryegrass mixtures.
Cryopreservation of Embryogenic Callus Cultures from Barley (Hordeum vulgare L.)
Authors: Hahne G. , Lörz H. 
Published: April 2006

AbstractEmbryogenic callus cultures of barley (Hordeum vulgare L.) were frozen in the presence of a cryoprotector and subsequentjy stored in liquid nitrogen. After thawing, a high percentage of cultures resumed growth after a lag‐period of 2–4 weeks. Plant regeneration was achieved at a frequency comparable to that observed in control cultures.
A Possible Association Between Heading Time and the GM‐A2 Locus in Bread Wheat
Authors: Laflandra D. , Margiotta B. , Porceddu E. 
Published: April 2006

AbstractA line without expression (null form) o: the α‐gliadins controlled by the 6A chromosome was found when screening electrosboretically single seeds of the bread wheat ‘Raeder’. Differences in heading time were also observed between this null line and the normal one. A linkage between 6A gliadin genes and heading time gene(s) is hypothesized.
Genetic Control of Tetracycline Sensitivity of Cytoplasmic Male Sterility (cms) in Chives (Allium schoenoprasum L.)
Authors: Tatlioglu T. , Wricke G. 
Published: April 2006

AbstractThe expression of cms in chives is controlled by a cytoplasmic factor (5), a restorer gene X/x (Tatlioglu 1982) and a temperature gene T/t (Tatlioglu 1987). In recent investigations (Tatlioglu 1986) it could be shown that tetracycline also influences the expression of 0731. To obtain information about the genetic control of tetracycline sensitivity of cms, tetracycline‐sensitive and tetracycline‐insensitive cms plants were crossed with each other as well as with maintainers and the reaction of their progeny to tetracycline base was investigated.The results indicated that the promotion of fertility due to high‐temperature conditions (24°C/24 °C, day/night) and tetracycline · base are independent of each other. The results of crosses can be explained by a nuclear gene, A/a, causing the tetracycline sensitivity when recessive. By using different genotypes of the three loci for restoration, temperature and tetracycline sensitivity highly advantageous material can be constructed for the investigation of the interaction between the nuclear and the mitochondrial genome in higher plants, for the molecular and functional basis of cms and for its use in plant breeding.
Economic Valuation of Varieties and Breeding Objectives
Authors: Müller P. , Zeddies J. 
Published: April 2006

AbstractBreeding planning and variety valuation can be supported only if weighting factors for the economically relevant performance traits are available. In plant breeding they are necessary for the calculation of selection indices as well as for the comparison of varieties and for quantifying the monetary impact of breeding progress.In this article the economic weights for the most important performance traits of sugar beet are calculated from the farmer's, the sugar factory's, and the national economy's point of view. Based upon economic weights for beet yield, sugar content, potassium, sodium, and ammo nitrogen content, a total of 19 varieties was compared with regard to physical and economic performance. The investigation shows that “best” and “worst” varieties differ in gross margin per ha by 270.— to 330.— DM.Indications were given for possibilities and limitations of the application of economic weights in breeding planning.
Rye Chromatin Variation in Yugoslavian Wheats
Authors: Petrovic S. , Dera A. R. , Gustafson J. P. 
Published: April 2006

AbstractC‐banding, which stains the heterochromatic regions of chromosomes, was utilized in order to ascertain whether or not several varieties from a Yugoslavian wheat‐breeding program contained a 1RS/1BL substitution or a 1RS/1BL translocation. Only one variety contained the 1R (1B) substitution, while in the remaining sixteen varieties, the 1RS/1BL translocation was present. The C‐banding results were confirmed utilizing an SDS‐PAGE analysis, and the results indicated that both techniques should be used together. In all of the Yugoslavian wheats containing observable rye chromatin, the C‐band corresponding to the nucleolus organizing region (NOR) was clearly reduced over that found in the wheat parents used in Yugoslavia or the other wheats from around the world containing either the substitution or the trans location. Some unknown selection pressure applied in the Yugoslavian wheat program in Novi Sad over the years has evidently caused a deletion of most of the rye NOR region.
A New Source of Resistance to Puccinia striiformis f. sp. tritici in Spring Wheats (Triticum aestivum)
Authors: Wellings C. R. , McIntosh R. A. , Hussain M. 
Published: April 2006

AbstractThe use of P. striiformis f. sp. tritici pathotypes virulent or avirulent with respect to both Yr6 and a previously undescribed source of resistance, designated YrA, allowed the recognition of the corresponding host resistance genes m a range of Australian and exotic spring wheats. The phenotypes conferred by the YrA resistance varied when exposed to contrasting light intensities in the post‐inoculation phase. The implications of the results in international studies of host resistance to P. striiformis f. sp. tritici are discussed.
Tan‐Spot Resistance Screening of Aegilops Species
Authors: Alam K. B. , Gustapson J. P. 
Published: April 2006

AbstractTwo hundred and twelve accessions of 8 diploid and 10 polyploid species of Aegilops were evaluated for resistance to tan‐spot disease of wheat, caused by Pyrenophora tritici‐repentis (Died.) Drechs., under greenhouse conditions. One or more accessions of Ae. bicornis, Ae. biuncialis, Ae. Crassa, Ae. columnaris, Ae. cylindrica, Ae. speltoides, Ae. squarrosa. Ae. triaristata. Ae. triuncialis, and Ae. Ovata showed resistance following a 24‐hour post‐inoculation wet period. With a 36‐hour wet period, diploids became only slightly or moderately susceptible and resistant polyploids became susceptible. A 48‐hour wet period resulted in still greater susceptibility of both diploid and polyploid species.
Comparison of Anther Culture and the Hordeum bulbosum Method for the Production of Doubled Haploids in Winter Barley
Authors: Devaux P. 
Published: April 2006

AbstractThe comparison, between the efficiency of anther culture and the Hordeum bulbosum method in barley was extended to the chromosome number distributions of all planes derived from the two techniques and the proportions of fertile doubled haploid plants which survived until maturity.The frequencies of haploid and spontaneously doubled haploid plants which were useful for practical breeding purposes were found to be around 90 % for both techniques. The remainder consisted of polyploid, mixoploid and aneuploid variants in the case of microspore‐derived plants and diploid interspecific hybrids in the progeny of the H. bulbosum method. The ploidy level distributions of the microspore‐ and H. bulbosum‐derived plants appeared to be independent of the genotype of the donor.There were no significant differences between techniques regarding the proportions, of plants which survived a severe winter and the production of fertile doubled haploid plants. Both techniques can therefore complement each other in a breeding programme and their relative merits are discussed.Possible ways of improving doubled haploid production in barley are suggested for increasing its use in breeding schemes.