bluuebunny/crossref_metadata_2025 huggingface dataset:
Early Generation Selection for Grain Yield in Narrow‐Leaf Lupin (Lupinus angustifolius L.)
Authors: Ratinam M. , Thuriling N.
Published: April 2006

Experiments were undertaken to identify an efficient method of selection for yield in early segregating generations of narrow‐leaf lupin crosses.

A first series of experiments involved simulation of F2 populations with mixtures of ten cultivars and advanced breeding lines. The performance of genotypes in mixtures sown at different densities was compared with their monoculture [commercial density) yields m the same and the following year. These comparisons provided a basis for assessing the value of different planting designs and different selection criteria in early generation selection for yield.

Correlated monoculture yield responses to simulated selection for single plant yield were similar for the honeycomb design and standard selection procedures at both low and commercial densities. These responses were much higher than that for grid selection in a low density population.

Correlated monoculture yield responses to selection for other plant characters were substantial only for flowering time and number of pod bearing branches under certain conditions. These responses were greatest for selection in a low density mixture and in the year following selection.

A procedure involving selection of the earliest flowering plants and selection within this group of plants with the highest number of pod bearing branches should be an effective approach to early generation yield selection in the narrow‐leaf lupin.
Pod Yield Comparison of Pure‐Line Peanut Selections Simultaneously Developed from Georgia and Zimbabwe Breeding Programs
Authors: Branch W. D. , Hildebrand G. L.
Published: April 2006

Crosses were made between two widely grown U.S. peanut (Arachis hypogaea L.) cultivars, ‘Florunner’ and Florigiant’, and two genotypes adapted to growing conditions on the plateau of tropical Africa, ‘Makulu Red’ and 486 GKP. F2 seed populations were equally divided between Georgia and Zimbabwe. Subsequently, pedigree selection was practised simultaneously at both locations in the early segregating generations. The highest yielding pureline selections were then interchanged, and combined yield evaluations were determined over three growing seasons at each location.

‘Florunner’, ‘Florigiant’, and the Georgia pureline selections tested at the Georgia location had significantly higher pod yields than ‘Makulu Red’, 486 GKP, and the Zimbabwe selections. Conversely, the mean yield of the Zimbabwe selections tested m Zimbabwe was significantly higher than that of the Georgia selections. Thus, the breeding environment under which selection is conducted among cross populations strongly influences the yield adaptability of selected peanut genotypes.
The HMW Glutenin Subunit and Gliadin Compositions of German‐Grown Wheat Varieties and their Relationship with Bread‐Making Quality
Authors: Rogers W. J. , Payne P. I. , Harinder K.
Published: April 2006

The HMW glutenin subunit and gliadin compositions of 57 German‐grown varieties of wheat were determined by 1D‐ and 2D‐polyacrylamide gel electrophoresis, respectively. A Glu‐1 quality score was calculated for each variety based on previously observed associations between individual HMW glutenin subuints and SDS‐sedimentation volume. The results indicated that approximately 30% of the variation in bread‐making quality of the varieties was accounted for by variation in the Glu‐1 quality score, and that this proportion was raised to 54 % if the presence or absence of chromosome 1BL.1RS was taken into account. It was also shown that allelic variation at the Gli‐1 and Gli‐2 loci had a relatively minor effect on quality; indeed, the only significant effect was associated with variation at Glu‐1, and the influence of this locus was principally due to the deterimental effect of 1BL.1RS.
Factors Affecting Fertilization Frequency in Crosses of Triticum aestivum cv. ‘Highbury’×Zea mays cv. ‘Seneca 60’;
Authors: Laurie D. A.
Published: April 2006

Crosses of ‘Highbury’×‘Seneca 60’ were studied to determine the effect of four crossing procedures on the frequency of fertilization. The procedures were: 1) glumes of emasculated florets left intact, 2) glumes cut to expose the stigmas, 3) intact glumes given a 75 mg 1‐1 GA spray 2 h after pollination, and 4) cut glumes given a 75 mg 1‐1 GA spray 2 h after pollination. Within each treatment florets with developmental ages ranging from 3 days before an‐thesis to 3 days after anthesis were pollinated. Fertilized florets were found in all four treatments. Overall, 20.2 % had only an embryo, 2.5 % had only an endosperm and 7.9 % had an embryo and an endosperm. Significant variation in the frequency of embryo formation, and hence in the frequency of potential plants, was found both between treatments and between developmental stages within treatments. The highest frequency (55.8 % of pollinated florets) was found in florets with intact glumes which had not received a GA spray and which had been pollinated on the day of anthesis. Cutting the glumes to expose the stigmas, pollinating earlier or later than the day of anthesis or application of a GA spray all tended to reduce the number of embryos. This was also the case when the total fertilization frequencies (embryos plus endosperms) were analyzed. The potential of wheat × maize crosses for wheat haploid production is discussed.
Effect of Bradyrhizobium Strain on Combining Ability for Nitrogen Fixation in Peanut (Arachis hypogaea L.)*
Authors: Phillips T. D. , Wynne J. C. , Elkan G. H. , Schneeweis T. J.
Published: April 2006

Improving the host genotype is one method of increasing biological nitrogen fixation by Bradyrhizobium in symbiosis with peanut (Arachis hypogaea L.), but host‐strain interactions also must be considered. The objective of this study was to estimate the effect of Bradyrhizobium strains on the inheritance of traits related to nitrogen fixation. Eight parents and the F1 generation of a diallel cross were evaluated in symbiosis with two bacterial strains for combining ability in a factorial arrangement in the greenhouse. The parents represented three taxa of cultivated peanuts. The two Bradyrhizobium strains NC 92 and NC 123 produced different general and specific combining ability, maternal (reciprocal general) effects, and reciprocal specific effects for the host genotypes. With strain NC 92, the peanut cultivars NC 7 and NC Ac 2821 had the best general combining ability for all traits evaluated; while, with strain NC 123, Robut 33‐1 exhibited a high general combining ability (GCA) for nitrogenase activity and specific activity. Genotype NC Ac 2821, when inoculated with strain NC 123, had a negative GCA effect for nodule number, while with strain NC 92 this cultivar had the highest GCA effect. The importance of strain selection in evaluating lines in a breeding program is discussed.
The Use of Multivariate Analyses to Eliminate Redundant Variables when Evaluating Potatoes for Chip Quality
Authors: Loiselle F. , Tai G. C. C. , Tarn T. R. , Christie B. R.
Published: April 2006

Selection for good chipping clones in potato breeding often takes place during the middle and late selection stages. This is due to the considerable resources needed for the assessment of several characteristics. Objective multivariate methods for the elimination of redundant variables were applied to eight standardized chipping quality traits recorded on advanced clones over 15 years at two locations in New Brunswick, Canada. The clones were evaluated of specific gravity and the following chipping scores: direct from the field in August; after 10 days storage at 13 °C; from 4 °C storage in February; from 4 °C storage in February with 1 week, 2 weeks, 3 weeks and 4 weeks reconditioning at 16 °C. Five elimination methods produced a similar deletion order. In every subset obtained, specific gravity and direct chipping from the field were always retained. Reconditioning treatments from one to four weeks after cold storage were shown to be the most redundant. The reduction in the number of traits from eight to four by every technique could recover more than 80 % of the original variation, showing that redundant variables were effectively discarded.
Cytology and Fertility of Hybrids and Amphiploids between Aegilops caudata L. ×Triticum turgidum (L.) Thell
Authors: Simeone R. , Pignoni D. , Blanco A. , Attolico M.
Published: April 2006

Interspecific hybrids and amphiploids between Aegilops caudata L. (2n = 2x = 14, CC) and Triticum turgidum (L.) Thell. conv. durum Desf M. K. (2n = 4x = 28, AABB) were produced. Such hybrids can be used to introduce desirable traits such as disease resistance into cultivated durum wheats. One of the durum parents was a ph I mutation of the cv. ‘Cappelli’ used for testing the possibility of direct introduction of alien variation into cultivated species. The amphiploids were obtained both through colchicine chromosome doubling and as natural non‐reductional mciosis products.

In both hybrids and amphiploids, meiotic pairing and fertility were studied. Hybrids showed varying degrees of pairing and, in addition to the one involving the ph 1 mutant, one high pairing hybrid was found (Ae. caudata× cv. ‘Capinera’). Cytological examination of microsporogenesis in amphiploids revealed a high frequency of bivalent formation. Fertility proved to be a very variable character since some of the amphiploids were almost completely sterile. The use of amphiploids in breeding programmes is discussed in relation to meiotic and fertility data.
Haploid Production from Barley Yellow Dwarf Virus Resistant Clones of Lolium
Authors: Boppenmeier J. , Züchner S. , Foroughi‐Wehr B.
Published: April 2006

The investigation was earned out to obtain double haploid homozygous lines of Lolium. Lolium multiflorurm ssp. gaudini cv. ‘Liwelo’, 44 clones and five different cultivars (cv.) of L. perenne were tested with regard to their anther culture response on a solid medium. Callus production and plant regeneration of the different genotypes were investigated. Within L. m. ssp. gaudini green plants have been obtained. In L. perenne significant genotypical differences in the in vitro reaction could be demonstrated. A high‐responding genotype was selected which produced a maximum of 20 % green plants. A variety × temperature interaction was found for the L. perenne varieties ‘Premier’ and ‘Barlenna’. The production of 34 green plants out ot eight clones enables a first analysis to be made of the inheritance of Barley Yellow Dwarf Virus resistance in L. perenne.
Petal Removal as a New Method to Control Pollen Transfer in the White Lupin (Lupinus albus L.)
Authors: Gärditz W. , Aldag R.
Published: April 2006

The control of pollen transfer is important for determining the components of yield performance of lupins. By tearing off the first, second and third petals and leaving the fourth and fifth untouched, key signals of the flower are removed and pollen vectors are prevented from visiting the flower. Although this partial removal of petals alters the biomechanics of the flower selfing remains unimpaired. The technique allows autogamy in to be obtained lupins under natural conditions and with little expense.
Selection for Seed Yield Production of Egyptian Clover (Trifolium alexandrinum L.) C. V. Fahl
Authors: Bakheit Bahy R.
Published: April 2006

Modified mass and family selection for seed yield production of berseem clover (Trifolium alexandrinum L.) c.v. ‘Fahl’ were applied for two generations. Two hundred plants (5 % intensity of selection) were selected for seed yield in the first season, 1985/86. In the second season, 1986/87, selection between and within half‐sib families was practiced. In addition, equal parts of seeds from each of the 200 selected plants were bulked to form the C1 modified mass selection; after establishing, the same procedure was adopted to form the C2 generation. The cycles 1 and 2 of half‐sib families and modified mass selection along with the base population family were evaluated for forage and seed yields. The realized gains from modified mass selection were 6.03 and 9.51 % for fresh forage yield, 5.57 and 10.86 % for protein yield and 13.23 and 16.19 % for seed yield in cycles 1 and 2, respectively, over the base population. The realized gain from family selection in cycle 2 as a percentage of the base population mean amounted to 11.32, 13.35, 17.47 and 3.15% for forage, protein, and seed yield and seed index, respectively.

The broad sense heritability, as estimated from the variance components was 89.63, 63.03, and 76.67 % for dry forage, seed yield and seed index, respectively.

Although, all these five traits (fresh, dry, protein, and seed yield and seed index) had positive correlation with each other, weak correlations were found between seed yield and forage yields. Furthermore, close associations were found among forage yield traits.
Inheritance of Corolla Size, Number of Stamens and Percentage of Plants with Petaloid Stamens in Evergreen Azaleas (Rhododendron Subsect. obtusa)
Authors: Heursel J , Garretsen Frida
Published: April 2006

Research has been carried out on the inheritance of corolla size, number of stamens and percentage of plants with petaloid stamens (double flower) in evergreen azaleas (Rhododendron Subsect. obtusa). For this purpose two incomplete diallel crosses were used. The first one included seven species and one cultivar and the second diallel 13 cultivars. In both diallels for all three characters the GCA mean squares were high. Also, the positive correlation between the parental values and the GCA estimates for flower size and number of stamens indicates that the expression of these characters is mainly determined by additive gene action. A negative correlation was found between GCA estimates for die n number of stamens and the percentage of plants with petaloid stamens. When breeding azaleas with large double flowers, parents can be directly selected on the basis of these characters since additive genetic variance dominates. As no genetic correlations were found between corolla size and number of stamens (percentage of plants with petaloid stamens) the breeding will not be hampered by unfavourable linkage of genes for these characters.
Early Embryo‐Sac Development and Intraspecific Variation in the Mean Endosperm Cell Cycle Time in Vicia narbonensis (L.)
Authors: Lazridou T. B. , Roupakias D. G. , Tsaitaris A. S.
Published: April 2006

The early endosperm development in seven Vicia narbonensis populations was studied under a 23/ 16 ° C day/night temperature regime. Double fertilization occurred in less than 24 h after pollination. Endosperm divisions were synchronous until the 8th division of the endosperm nuclei. Aberrant endosperm nuclei were first observed alter the 8th division and their number increased after the 10th division. Endosperm nuclei continued to divide until the 12th day after pollination. During the following days a decrease in the number of endosperm nuclei was observed together with a substantial increase in the number of aberrants. Endosperm nuclei finally disintegrated. Neither cellularization nor starch deposition was observed in the endosperm. A positive correlation (r 0.69) was recorded between early pod length and the number of endosperm nuclei found in the ovules within each pod.

In the populations studied the number of endosperm nuclei increased at a steady but different rate. This was followed by embryo development as well. It was concluded that intraspecific variation in the mean endosperm cell cycle time exists in Vicia narbonensis and that populations A 174 and A 202 should be more compatible to Vicia faba ev. ‘Polycarpe’ than population A 201.
Characteristics and Inheritance of Seed‐Ageing Induced Mutations in Lettuce (Lactuca sativa L.)
Authors: Rao N. K. , Roberts E. H.
Published: April 2006

Mutations affecting qualitative traits were induced by seed ageing in lettuce. The mutant plants were isolated in the A2 generation and included chlorophyll‐deficient types (chlorotica, lutescens, chlorina‐virescens, luteo and viridalbo maculate), and morphological variants (dwarf and narrow, thick and curly leaf types). The leaf mutants were found to be either partially or completely sterile. Segregation pattern of the mutants in A3 generation showed that, except for the maculata types, all chlorophyll deficiencies and the dwarf mutant are controlled by single recessive nuclear genes. The genetic status of the leaf mutants was not clear, due to possible pleiotropic effect of the mutant genes in inducing gametophytic sterility. The maculata mutants exhibited sorting out of the normal and chlorophyll deficient regions during vegetative development and segregated for different degrees of chlorophyll deficiency in selfed progenies. The maculata mutants probably originated by plastome mutations induced by nuclear mutator genes.
Evaluation of Differential Lines and a Collection of Sunflower Parental Lines for Resistance to Broomrape (Orobanche cernua) in Spain
Authors: Melero‐Vara J. M. , Dominguez J. , Fernandez‐Martinez J. M.
Published: April 2006

Broomrape (Orobanche cernua Loelf.) is a sunflower parasite which has become a potential threat to this crop in Spam with an increasing incidence in recent last years. In order to investigate the racial situation of the parasite in Spam and to evaluate the resistance of differentials and inbred lines currently used in breeding programmes, two experiments were carried out. In the first, two sets of European sunflower differentials were inoculated with three broomrape populations from different geographical origin. The second experiment studied the reaction to the parasite of 38 inbred lines in comparison with resistant and susceptible checks. Reactions of differential lines resistant to known European broomrape races ranged from complete immunity of lines P‐1380‐2A and ‘Jdanovski 8281’ to complete susceptibility of ‘Record’ and the universal suscepts. These results confirmed the existence of several physiological races of broomrape in Spain and a different racial composition from that of Eastern Europe. Results from the second experiment showed good resistance of half the restorer lines tested and 36 % of the maintainers and cms lines. This material together with the resistant differential lines constitutes good starting material to be used in developing cultivars resistant to broomrape populations in Spain.
Observations on the in vitro Production of Vernalized Sugar Beet (Beta vulgaris L.)
Authors: Sitbon Mireille
Published: April 2006

Rooted shoots of sugar beet were vernalized in vitro for three months and then transplanted into the field without acclimatization. All surviving plants bolted two months later.
Components of a Cytoplasmic Male Sterility System in Resynthesized and Cultivated Forms of Oilseed Rape (Brassies napus L.)
Authors: Chen B. Y. , Heneen W. K. , Gertsson B. , Halldén C.
Published: April 2006

Male sterile Brassica napus L. plants were found in breeding material which was used for the development of yellow‐seeded oilseed rape. The genetic studies indicated that the male sterility was conditioned by the presence of maintamer genes in the nuclear backgrounds of two newly resynthesized B. napus lines, No7076 and No7406, in combination with a male sterility‐inducing cytoplasm (S) which is frequently found in cultivated forms of B. napus. Test crosses with nap maintainer and restorer lines support the conclusion that the observed male sterility is of nap type. Furthermore, the Eco RI restriction pattern of mitochondrial DNA of the (S) cytoplasm was identical to that of the nap cytoplasm. Hence, we conclude that we have uncovered a new source of maintainer lines for the nap system which could potentially lead to the production of a better maintainer/restorer system for use in hybrid oilseed rape breeding programmes. However, more work is needed to reduce the glucosinolate content of the maintainer lines and to determine the factors controlling the phenotypic expression of the system.
Effects of Growth Regulator and Genotype on Production of Wheat and Triticale Polyhaploids from Anther Culture*
Authors: Hassawi Dhia S. , Qi Jiahua , Liang G. H.
Published: April 2006

Homozygous doubled‐haploid plantlets derived from anther culture of wheat (Triticum aestivum L.) and triticale (×Triticosecale Wittmack) are useful breeding materials. However, efficiency of an‐drogenesis needs improvement. We used media (basic components, are the same as 85DI2) each containing one of the seven auxins [2,4,5‐trichlorophenoxyacetic acid (2,4,5–T), P‐chloraphenoxyacetic acid (pCPA), 3,6‐dichloro‐o‐anisic acid (dicamba), 4‐amino‐3,5,6‐trichloropicolinic acid (picloram), indole‐3‐butrytic acid (IBA), indole‐3‐acctic acid (IAA), and 2,4‐dichlorophenoxyacetic acid (2,4‐D) as a control] in combination with 6‐furturyl‐aminopurine (kinetin). In addition, each of the four cytokinins [6‐benzylaminopurine (6‐HA), 2‐isopenlylnyl adenine (2‐ip), 6‐(4‐hydroxy‐3‐meihylbut‐2‐enylamino) purinc (zeatin), and kinetin as a control] was tested in combination with 1‐naphthalene acetic acid (NAA). Anthers containing microsporcs at miduninucleatc stage from live wheat cultivars (Angus, Centurk, Chris, K.itt, and Pavon 76) and two octoploid trilicale lines (T81, T82) were tested mainly for callus induction and polyhaploid production on each of the 11 media. The cultivar × medium interaction was not significant, When averaged over all growth regulators, Pavon was (he best cultivar which produced 14.4 % calli and 23 % polyhaploid plantlets. Averaged over all cultivars, the medium containing 2, 4‐U produced the highest calli (13.9 %). Undifferentiated calli were regenerated on 87T1 medium, which contained IAA (1 mg/1) and kinetin (2 mg/1).
Stability Analysis of Yield in Maize, Wheat and Sorghum and its Implications in Breeding Programs*
Authors: Yue Guilan , Perng S. K. , Walter T. L. , Wassom C. E. , Liang G. H.
Published: April 2006

Six stability statistics: (bi, s2di, , , and ) were estimated for maize, wheat and sorghum in different environments by using three statistical models. The significant linear portion of genotype × environment interaction for maize indicates different hybrids responded differently to environments, whereas the non‐significant genotype × environment interaction (linear) were found for wheat and sorghum suggest that all genotypes responded similarly as the environments change. However, the highly significant pooled deviations (deviation from regression) for all three crops make yield predictions from the model less reliable. When regression coefficients (bi) were non‐significant, s2di, became an important statistic in estimating stability. It appears that the regression coefficient, bi, was best used to estimate genotypic adaptability, whereas s2di, for stability. Maize and sorghum had negative correlations between the mean yield and stability statistics, s2di, , and , suggesting that high yield and stability are not mutually exclusive in the range of environments used in this study; however, such correlations did not occur in wheat. Thus, maize and sorghum hybrids with high yield potential and high stability could be identified and selected. Correlations between mean yield and bi, or , were positive and significant for maize and sorghum but were non‐significant for wheat, indicating that such relationships may be species specific. Under a given set of testing environments, the stability ranking associated with each maize hybrid is correlated to and depends on other hybrids included in the analysis.
Independent Inheritance of Flower Colour and Male‐Fertility Restorer Characters in Brassica napus L.
Authors: Chen B. Y. , Heneen W. K.
Published: April 2006

Available material of oilseed (Brassica napus L., AACC) comprises two yellow‐flowered breeding lines and a white/pale‐flowered line of resynthesized rape. The flower colour white/pale is dominant over yellow, and is controlled by a gene located in the C‐genome. The yellow‐flowered genotypes acted as restorer lines and the white/pale‐flowered genotype as a maintainer line in a cytoplasmic male sterility system. The segregation pattern of flower colour and male fertility restorer characters were studied in F2 generations of crosses between these lines, also in a three‐way cross additionally including a yellow flowered B. campestris (AA) line. Evidense was obtained in support of the conclusion that the flower colour and male fertility restorer characters are monogenically controlled and independently inherited. Whether the male fertility restorer gene is located in the A or C genome remains to be determined.
A Survey of the Anther Culture Response of Brassica oleracea L. Cultivars Grown Under Field Conditions
Authors: Arnison P. G. , Keller W. A.
Published: April 2006

Anther culture studies were conducted on a wide variety of different vegetable Brassica oleracea L. cultivars grown under field conditions. Representative selections were included from different varieties including: broccoli, var. italica; heading broccoli, var. botrytis; Brussels sprouts, var. gemnifera; Chinese Kale, var. alboglabra; Kales, vars. acephala, medullosa, ramosa, selensia; cauliflower, var. botrytis; kohlrabi, var. gongylodes; and cabbage, vars. capitata and sabanda. At least some microspore derived embryos were recovered from the majority of cultivars tested; however, rates of embryo formation were sometimes lower than those obtained under controlled environmental conditions. In general the anther culture response was greatest for cabbage and other vegetables that required vernalization for flowering. Results were lower for materials exposed to high temperature stresses before culture. Nevertheless, it is clear that the use of anther culture procedures in breeding programs is possible without access to extensive controlled environmental facilities.
Production of Haploid Sugar Beet (Beta vulgaris L.) by Culturing Unpollinated Ovules
Authors: Lux H. , Herrmann L. , Wetzel Claudia
Published: April 2006

The culture of unpollinated ovules is shown to be a suitable system for the production of haploid sugar beet (Beta vulgaris L.). The yield of haploids depended upon the genotype and varied between 0 and 13 % with a mean of 1.0 %. Haploid plants could be produced from approximately 50 % of all genotypes examined.

The majority of the haploids isolated (about 90%) maintained the haploid genome level during the in vitro culture and propagation; 10% of the haploid clones showed a spontaneous doubling to the diploid genome level.
Further Studies on the Restoration of Fertility in Triticum durum×T. timopheevi Hybrids
Authors: Pandey H. N. , Rao M. V. , Singh S. V.
Published: April 2006

Twenty one F1 hybrids involving three Triticum durum cultivars and eleven forms of T. timopheevi were backcrossed to their respective durum parents. Backcross fertility (BC1 grain set) of these sterile hybrids improved with the rise in temperature at the time of pollination. A mean temperature of less than 20 °C results in poor seed set while higher mean temperatures around 24 °C result in increased seed set. It is suggested that a large number of backcross seeds can be produced by pollinating these hybrids late in the season, i.e., after 20th of March in northern India.
Relationship Between Gluten Strength and Glutenin Proteins in Durum Wheat Cultivars
Authors: Carrillo J. M. , Vazquez J. F. , Orkellana J.
Published: April 2006

An electrophoretic study of gliadin and glutenin proteins, mainly low‐molecular‐weight (LMW) Glutenin Subunits, was undertaken to investigate possible assoeiations between these proteins and gluten strength. Thirty‐eight durum wheat cultivars having different origins and currently grown in Spam were analysed. Different electrophoretic methods were used to analyse the seed storage proteins. Protein grain content was estimated and gluten strength was measured by the SDS‐sedimentation test. New patterns for LMW glutenins were observed. Besides the known patterns of LMW‐1, associated with γ‐gliadin 42, and LMW‐2 associated with γ‐gliadin 45, six cultivars had LMW‐2− associated with γ‐gliadin 43, one cultivar showed LMW‐2* associated with γ‐gliadin 44, and another cultivar, null for γ‐42 and γ‐45, had LMW‐1−. Significant differences for gluten strength were found among groups of cultivars with different LMW patterns. High molecular weight glutenins were found in general to be poor indicators of viscoelastic properties, although band 20 showed a negative influence on quality. The results are discussed in relation to development ol cultivars with good gluten strength.
Variation of Seed Glucosinolates in Lines of Brassica napus
Authors: Kräling K. , Röbbelen G. , Thies W. , Herrmann M. , Ahmadi M. R.
Published: April 2006

The glucosinolate (GSL) pattern of 93 resynthesized (resyn) repeseed lines was examined over three years, and five stable genotypes with distinct GSL profiles were identified. Typically the resyn B. napus profile exhibited progoitrin as the main GSL, but contained sinigrin. The different GSL patterns of the four deviating lines are discussed with respect to the proposed biosynthetic pathway. Within the resyn and further extensive breeding materias, screening for low indolyl GSL contents resulted in finding one genotype with an extremely low 4‐hydroxy‐gluco‐brassicin and glucobrassicin content. Furthermore, other lines were identified, over a wide range of indolyl GSL contents. The values were stable over two years.
Genotypes of Perennial Ryegrass (Lolium perenne L.) with High Anther‐Culture Response through Hybridization
Authors: Halberg N. , Olesen A. , Tuvesson I. K. D. , Andersen S. B.
Published: April 2006

Anther‐culture response in Lolium perenne was studied in the hybrid populations from three responsive diploid parent clones to obtain genotypes with superior anther‐culture response through hybridization. Genetic variation for anther‐culture response was significant both within and between the four hybrid families and their parents. A reciprocal effect was indicated for embryo formation and regeneration percentages for one of the cross combinations. Among 55 hybrid clones tested in two environments, 6 clones were identified with an anther‐culture response level superior to their parents. While the parents produced one green plant or less per 100 anthers, these superior clones produced from 11 to 59 green plants/100 anthers, mainly as the result of improved embryo formation and improved percentages of regenerated plants being green. A significant correlation (r = 0.397**) was observed between embryo formation and percentage of green plants. The results are discussed with regard to the possible transfer of anther‐culture response to non‐responsive breeding material through hybridization.
Callus Formation and Plant Regeneration from Protoplasts Derived from Suspension Culture of Rice (Oryza sativa L. cv. ‘Taipei 177’)
Authors: Biswas G. C. Ghosh , Zapata F. J.
Published: April 2006

Protoplasts were isolated from young inflorescence‐derived suspension cultures of a japonica rice cultivar ‘Taipei 177’. The isolated protoplasts which were cultured either in liquid, agar on Sea plaque agarose underwent sustained division. Maximum plating efficiency of 1.06% occurred in a medium containing macroelements of KM, microelements and vitamins of B5, 0.5 % Sea plaque agarose, 1.0 mg/l of 2,4‐D, and glucose as an osmotic stabilizer. Green and albino plants were regenerated from the protocalli in MS semisolid medium containing 4 mg/l BAP, 0.5 mg/l NAA and 500 mg/l casein hydrolysate (MS18–2).
Transfer of Tomato Leaf Curl Virus Resistance from Lycopersicon hirsutum f. glabratum to L. esculentum
Authors: Kalloo  , Banerjee M. K.
Published: April 2006

Six lines, i.e., H‐2, H‐11, H‐17, H‐23, H‐24, and H‐36, resistant to Tomato Leaf Curl Virus (TLCV) have been developed with controlled introgression of L. hirsutum f. glabratum into Lycopersicon esculentum. The disease incidence, 120 days after inoculation, of those lines derived from L. hirsutum f. glabratum ranged from 8.3 to 35.0 %, whereas in susceptible varieties it ranged from 95.0 to 100 %. The coefficient of infection (CI) values in the resistant lines were very low, ranging from 0.25 to 4.55, whereas in susceptible varieties CI values ranged from 60.56 to 88.96. Line H‐2 had the highest resistance by showing the least disease incidence and CI values. The fruit size and days to maturity in resistant lines were close to those of cultivated susceptible varieties. These lines have the scope for being used as varieties in the TLCV infested areas or as foundation lines for further genetic improvement.
Selection in Early Generations of Dried Peas, Pisum sativum L. II. Significance of the Environment of Selection
Authors: Stelling D. , Ebmeyer E. , Snoad B.
Published: April 2006

In early generations peas arc frequently grown widely‐spaced against wire netting under growing conditions considerably different from the commercial cultivation practice of dense stands. In 1985 and 1986, five morphologically different pea varieties were grown both widely‐spaced against wire and in dense stand in plots. In the plot stands no methods to prevent the peas from lodging were used. Grain yield and yield‐related traits were recorded in both environments of selection, i.e. ‘wire netting’ and ‘plot stand’. Data were analyzed with respect to the suitibility of the environment ‘wire netting’ for selection for grain yield to be realized in commercial stands of the crop.

Against wire, the grain yield, number of podded lateral branches, number of podded nodes/main stem, and the profile of grain yield/node on the main stem were the most responsive characters as compared to the standard plot with a dense stand. The relative increase differed between genotypes, which was also indicated by highly significant genotype × environment interactions. Only small changes consistent over genotypes were observed for thousand grain weight (slightly lower), number of seeds/pod (slightly increased) and grain yield/pod (slightly higher).

Against wire, the expression of varietal variation was higher for most characters. In addition, single plant error was lower, so that at the wire heritability values based on individual plants were larger than in the plots.

The significance of the present results and the effects of competition on selection in early generations in dried peas are discussed.
In‐vitro Fertilization of Ovules of Some Species of Brassicaceae*
Authors: Zenkteler M.
Published: April 2006

The method of in‐vitro fertilization of ovules can be successfully applied to various species of Brassincaceae. Mature embryos and plants were obtained after in‐vitro pollinating the ovules of Arabis caucasica, Brassica napus, B. oleracea var. sabellica (kale), B. oleracea var. italica (broccoli), Diplotaxis tenuifolia, Moricandia arvensis and Sisymbrium Loeselli. In the case of Sinapis alba fertilization and embryo development did not occur. The same method has been successfully used for obtaining hybrid immature embryos at different stages of development from crosses between B. napus X D. tenuifolia, B. napus X M. arvensis, B. oleracea var. italica X D. tenuifolia, D. tenuifolia x B. napus, D. tenuifolia. X M. arvensis and D. tenuifolia X S. Loeselli. The present findings show that in‐vitro pollination of ovules of various species of Brassicaceae makes it possible to (a) perform the whole process of fertilization and embryogenesis; and (b) obtain intergeneric hybrid embryos.
Comparative Morphological Studies of Microspore Derived and F2 Plants Obtained from an Interspecific Rice Hybrid Oryza sativa Linn. ×O. rufipogon Griff.)*
Authors: Rout J. R. , Sarma N. P.
Published: April 2006

Anther culture of an interspecific rice hybrid from a cross of Oryza sativa× O. rufipogon was attempted. Of the 117 regenerated pollen clones, 56 could survive to maturity. A majority of these were either haploids or doubled haploids and very few turned out to be chromosomal variants. Comparative study of doubled haploids and the seed derived F2 plants indicate the distinct advantages of anther culture techniques. (1) Androgenic plants, though few in number, showed greater ariation for all the traits with the exception of ear bearing tillers. (2) Predominance of recombinants with wild traits was observed in F2 segregation. (3) It was possible to recover indica type recombinants among the anther‐derived plants with one or two traits introgressed from O. rufipogon. These results suggest the feasibility and utility of anther culture in distant hybridization for incorporation of alien variation into cultivated rice.
Genetic Variation in Alfalfa, Sweet Clover and Fenugreek for the Activity of Symbiosis with Rhizobium meliloti
Authors: Provorov Nicolai A. , Simarov Boris V.
Published: April 2006

The aim of this work was to examine variation for activity of symbiosis with Rhizobium meliloti in alfalfa, sweet clover and fenugreek. Seed specimens were obtained from the collection of the All‐Union Research Institute for Plant Breeding and Rhizobium strains from the All‐Union Research Institute for Agricultural Microbiology, both in Leningrad. Sterile methods of vegetative culture were employed. Statistical analysis of data on inter‐ and intracultivar variation allow one to suppose that in alfalfa and sweet clover, nitrogenase activity and symbiotic efficiency (ability of plants to increase biomass after inoculation) are controlled by different groups of genes. The latter symbiotic property is more strictly controlled by host genotype than the former. Fenugreek appeared to be more variable in its capacity for symbiosis than alfalfa and sweet clover. Differences between genotyyes in symbiotic activity correlate with division into subspecies and are inherited in self‐fertile progeny of fenugreek plants. Differences between R. meliloti strains for the efficiency of symbiosis with heterogceic natural fenugreek population are expressed to a lesser degree than with plants of more homogenic cultivar populations.
Utilization of Intervarietal Chromosome Substitutions in Breeding Winter Wheat
Authors: Meinel A. , Holldorf A. , Jakuszeit C.
Published: April 2006

Using monosomic lines of wheat cultivars ‘Palur’ and ‘Compal’ as recipient parents as well as disomic substitution lines of chromosomes 5A and 5D of the wheat cv. ‘Atlas 66’, F3‐populations and BC1′‐ to BC3′‐populations with limited and free recombination of the 20 and 21 parental chromosomes, respectively, were realized and tested in field trials in comparison to the corresponding recipient cvs. ‘Palur’ and ‘Compal’. F3‐ and BC'‐populations with the homozygous chromosomes 5A and 5D of the wheat cv. ‘Atlas 66’ expressed higher and more stable grain protein values than the comparable populations with free recombination of the same chromosomes. The grain protein content of populations with limited recombination was significantly increased compared with the recipient cultivars. Some advantages of using intervarietal substitutions in wheat breeding are discussed.
Effective Diploidization of Microspore‐Derived Haploids of Rape (Brassica napus L.) by In Vitro Colchicine Treatment
Authors: Mathias Regine , Röbbelen G.
Published: April 2006

A technique for the in vitro colchicine treatment of microspore‐derived haploids of rape (Brassica napus L.) is presented. This allows effective and time‐saving chromosome doubling. The most effective method consists of an application of 50 mg/1 colchicine in a liquid B5 medium to the rooted micro‐spore‐derived plantlets for 4–8 days. By this treatment more than 50 % of the plants developed at least diploid sectors. A change of medium after some days may even increase this diploidization rate.
Breeding Potential of Root Chicory (Cichorium intybus L. var. sativum)
Authors: Frese L. , Dambroth M. , Bramm A.
Published: April 2006

The objective of this study was to investigate the breeding potential of the inulin‐containing root chicory which has potential as a new industrial crop. Polycross families and reference varieties were grown in field experiments at 3 locations to assess their performance and the amount of variation available for breeding. Significant variation between polycross families for all characters except for glucose content and the ratio total sugar/dry matter content was observed. Compared to ‘Fredonia’, 12 out of 72 polycross families gave between 15 % and 24 % more total sugar yield. Preliminary estimates for the heritability of two yield components were calculated by means of the parent‐offspring regression analysis. Additive genetic variance seems to determine the inheritance of fructose and total sugar content. All findings suggest that the total sugar yield of root chicory can be considerably increased by breeding.
The Effect of Colchicine as a Chromosome Doubling Agent for Wheat‐Rye Hybrids as Influenced by pH, Method of Application, and Post‐Treatment Environment
Authors: Taira Tomoaki , Shao Z. Z. , Hamawaki H. , Larter E. N.
Published: April 2006

Hybrids of wheat (Triticum durum) × rye (Secale montanum) (2n = 21) were treated with a 0.06 % solution of colchicine. In the induction of fertile plants, fertile spikes, and seed‐set per spike, the root immersion technique was 21.7 %, 14.1 %, and 4.4 % respectively more effective than the use of the inverted vial. Colchicine solutions ranging in pH from 3.5 to 7.5 with the root immersion technique reached the highest frequencies of fertile (or partially fertile) hybrids (77.7 %), and fertile spikes (68.9 %) at a pH 5.5 used for the treatment, although the highest overall percentage of large Q seeds resulted from treatments at low pH (3.5). The overall mean frequency of induced fertile plants was six‐fold higher when treated in a growth chamber (19/15 °C day/night temperature and 18 h photoperiod) compared to treatments conducted in a greenhouse. The frequency of euploidy (2n = 42) was found to be highest in the large seed class and lowest, i.e. just about 50 %, in the class of small seeds.
Endopeptidase EP‐1 as a Marker for the Eyespot Resistance Gene Pch‐1 from Aegilops ventricosa in Wheat Line ‘H‐93‐70’
Authors: Vahl Ute , Müller G.
Published: April 2006

Biochemical marker endopeptidase EP‐1 was used to determine that an eyespot resistance gene, transferred from Aegilops ventricosa to the hexaploid wheat line ‘H‐93‐70’ is located on the long arm of the chromosome 7D.
Methods for Selection of Low‐Temperature Tolerant Mutants of Chrysanthemum morifolium Ramat. Using Irradiated Cell Suspension Cultures II. Preselection in vitro under Low‐Temperature Stress
Authors: Preil W. , Huitema J. B. M. , De Jong J.
Published: April 2006

The effect of in vitro cold treatment (+6°C, 90 days) on selection of low‐temperature tolerant (LTT) mutants was investigated using X‐irradiated (15 Gy and 20 Gy) and non‐irradiated cell suspensions of Chrysanthemum morifolium cv. ‘Parliament’. Low temperature reduced significantly the number of regenerating calli, especially in the irradiated cultures. After the end of the cold stress 684, 197 and 54 plants were obtained from the 0 Gy, 15 Gy and 20 Gy treated cultures, respectively. Testing these plants in the greenhouse (+12 °C, winter low‐light) most of the early flowering variants were selected from the 15 Gy population.
Segregation Pattern of Decumbent, Climbing and Bushy Growth Habits in Vigna unguiculata (L.) Walp.
Authors: Uguru M. I. , Uzo J. O.
Published: April 2006

F1 and F2 data from crosses of cowpea accessions with three different growth forms showed that the inheritance of growth habit is governed by two allelic pairs, AA and BB. The genetic ratio obtained implicated a modifier gene interaction in which the genotype A‐B‐ has the decumbent growth habit; the genotype aaB‐ has the climbing and aabb has the bushy habit. While the decumbent growth habit was dominant and epistatic over the climbing habit, the decumbent and the climbing growth forms were each monogenically dominant over the bushy habit.
Donor Plant Growth Conditions and Regeneration of Fertile Plants from Somatic Embryos Induced on Immature Zygotic Embryos of Sunflower (Helianthus annuus L.)
Authors: Jeannin G. , Hahne G.
Published: April 2006

Immature zygotic embryos of the sunflower inbred line ‘Ha 300’, cultivated on a modified MS medium containing 6‐benzyladenine and a high amount of sucrose, regenerated fertile plants via direct somatic embryogenesis. Plant regeneration from immature sunflower embryos is generally characterized by a relatively high experimental variability resulting from the interactions of multiple factors. We present here a study of some of the factors acting on the donor plants and their influence on the capacity to regenerate plants.

Repeated experiments during a 2‐year period with greenhouse‐grown as well as field‐grown plants led to the following conclusions: (i) The use of pesticides, unavoidable in the greenhouse, is compatible with routine regeneration of fertile plants, (ii) The plant growth retardants tested were useful for the production of healthy plants in the greenhouse and had no effect on the regeneration capacity.
Critical Discussion on Abortive Interspecific Crosses in Brassica
Authors: Nishiyama I. , Sarashima M. , Matsuzawa Y.
Published: April 2006

In most interspecific hybridization among diploid Brassica species (n = 8, 9, 10), few or no hybrids are obtained, and the three crosses of tetraploid (n = 17, 18, 19) by diploid species are usually only partially successful, especially in one of the reciprocal crosses. Such a cross‐incompatibility complex is explained in this paper by a polar‐nuclei activation (PNA) hypothesis which proposes two reversible functions, a normal reproduction and a sexual barrier, of double fertilization in higher plants. The first, i.e. the relative activating value (AV) of diploid species, was estimated as 1.0–3.5, whereas that of tetraploid species was 2.7–5.2. In addition, crosses with a polar nuclei activation index (AI) of about 15–87 % were compatible but those beyond the two limits were incompatible, 50 % of those showing normal seed development after self‐pollination.
Genetic Variation in Commercial Varieties and Natural Populations of Sheep's Fescue, Festuca ovina s.l.
Authors: Weibull P. , Ghatnekar L. , Bengtsson B. O.
Published: April 2006

Genetic variation in two commercial varieties, ‘Liwally’ and ‘Barok’, and two Swedish natural populations of sheep's fescue, Festuca ovina s.l., was studied by means of starch gel electrophoresis. Variation in allele frequencies was found at the Dial, Gpi2, Got2, Pgdl, Pgm, Tpil and Tpi2 loci. ‘Liwally’, belonging to ssp. vallesiaca, showed clear differences compared to the other samples which belong to ssp. capillata and ssp. vulgaris. Genetic diversity, as measured by per cent polymorphic loci, number of alleles per locus and frequency of heterozygotes, was high in all samples in agreement with what has been found in other perennial, outcrossing mono‐cotyledonous species with a wide distribution. The bred varieties and the wild populations did not statistically differ with respect to frequency of heterozygotes or number of alleles, though the last value was lower in the domesticated lines than in the natural populations. No significant deviation from the expected Hardy‐Weinberg proportions was found in any of the samples.
Confirmation of a 4BL/5RL Wheat‐Rye Chromosome Translocation Line in the Wheat Cultivar ‘Viking’ Showing High Copper Efficiency
Authors: Schlegel R. , Werner T. , Hülgenhof E.
Published: April 2006

The N‐ and C‐banding patterns of the chromosomes of the hexaploid wheat cultivar ‘Viking’, and the hairy‐necked line derived from it, were described. Except for chromosome 4B (formerly 4A), no significant variation in banding patterns were found between the two genotypes. In addition to a 5BS.7BS (5BL.7BL) translocation in both genotypes, the presence of a small 5RL rye segment in a terminal position on the long arm of chromosome 4B was suggested by banding and confirmed by meiotic analysis, and by the hairy neck marker as well as by rye‐specific leaf esterase bands in the translocation line. The translocation breakpoint is presumed to be located in the distal 4BL2.2 and/or 5RL2.3 band. The hairy‐necked ‘Viking’ was shown to be copper efficient. Its utilization in wheat breeding programmes is proposed.