bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic variation in testcrosses of European maize inbreds for resistance to the European corn borer and relations to line per se performance
Authors: Kreps R. C. , Gumber R. K. , Schulz B. , Klein D. , Melchinger A. E. 
Published: April 2006

AbstractThe European com borer (ECB) Ostrinia nubilalis H. is a major pest in World maize Zea mays L. production. Objectives of this study were to (1) investigate the genotypic variance and covariance in testcrosses of European flint and dent inbreds for ECB resistance and agronomic traits, and (2) estimate the correlation between line per se and testcross performance for ECB resistance traits. A total of 16 flint and 24 dent inbreds and their testcrosses with two testers from the opposite germplasm pool were evaluated in four and three German environments, respectively. Using artificial infestation with ECB larvae, resistance was assessed by damage rating of stalks, tunnel length in dissected stalks, and relative yield of infested plots compared with protected plots. Yield losses due to ECB damage in testcross hybrids amounted to 40%. Significant genotypic variances between flint and dent lines and high heritabilities were found for damage rating of stalks for both line per se and testcross performance. Heritabilities were low or intermediate for tunnel length and relative grain yield. Correlations between line per se and testcross performance were tight for the damage rating of stalks and moderate for tunnel length and relative yield in both flint and dent germplasm. For damage rating of stalks, per se performance of lines tested in a few environments can be used to predict their testcross performance. In contrast, assessment of testcross performance for tunnel length and relative yield requires evaluating testcrosses with several testers in multi‐environment trials.
Polymorphism of waxy proteins in Iberian hexaploid wheats
Authors: Rodriguez‐Quijano M. , Nieto‐Taladriz M. T. , Carrillo J. M. 
Published: April 2006

AbstractA collection of 130 cultivars of bread wheat, 332 landraces of bread wheat and 144 spelt wheats was analysed for waxy proteins in the grain. The electrophoretic patterns showed very low polymorphism and most of the hexaploid wheats had the Wx‐Ala, Wx‐D1a and Wx‐B1 alleles of ‘Chinese Spring’. Two alleles were detected at Wx‐A1 (Wx‐A1a, and Wx‐A1b (null)), the latter was present in only 5.1% of the bread wheat landraces and 7.6% ofthe spelt wheats. No allelic variation was found at the Wx‐D1 locus and all the hexaploid wheats had the Wx‐D1a allele. Wx‐B1 was the most polymorphic locus, with three alleles detected: Wx‐B1a, Wx‐B1b (null) and Wx‐Blc coding for a Wx‐B1 protein with a slightly different mobility from Wx‐B1a. The null Wx‐B1b allele was found in 10.8% of the bread wheat cultivars, 21.4% of the bread wheat landraces and 12.5% of the spelt wheats. Among the 604 hexaploid wheats analysed, only two bread wheat landraces (0.6%) and two spelt wheats (1.4%) had the null allele at both Wx‐A1 and Wx‐B1 loci.
Comparison of intra‐ and inter‐pool crosses in faba beans (Vicia faba L.). II. Genetic effects estimated from generation means in Mediterranean and German environments
Authors: Schill B. , Melchinger A. E. , Gumber R. K. , Link W. 
Published: April 2006

AbstractGenetic diversity between parents is important for hybrid breeding and for maximum usefulness of a cross in pure line breeding. However, wide crosses may suffer from poor adaptation in the target environments and recombination losses owing to disruption of favourable epistatic gene combinations. In this study we investigated the importance of various gene effects for different traits in the parents and generations F1 to F5 derived from 99 intra‐ and inter‐pool crosses among 20 lines of the Minor, Major, and Mediterranean germplasm pools of faba bean in Mediterranean and German environments. Yield performance of parental inbreds and progenies of crosses in different selfing generations was high in the region of adaptation of the respective germplasm pool. Heterosis for yield was greatest in interpool crosses of Minor × Mediterranean germplasm, amounting to 106% in Mediterranean and 72% in German environments. Interpool crosses exhibited significantly greater heterosis compared with intrapool crosses in both mega‐environments. Generation means analysis revealed the importance of additive gene effects and dominance × dominance epistasis in Mediterranean and German environments. Dominance effects and additive × additive epistasis for yield were negligible in most crossing groups. Since intrapool crosses of Mediterranean germplasm in Mediterranean environments and crosses of Minor and Major germplasm in the German environments were most promising, we suggest crosses among adapted germplasm for hybrid breeding and for establishing new base material in line breeding in faba bean.
The influence of auxin type on the array of somaclonal variants generated from somatic embryogenesis of eggplant, Solanum melongena L.
Authors: Hitomi A. , Amagai H. , Ezura H. 
Published: April 2006

AbstractSomaclonal variation is a possible source of variation in plant breeding. To apply this approach to eggplant breeding, somaclonal variations were observed among plants regenerated through somatic embryogenesis induced by 1‐naphthaleneacetic acid (NAA) or 2,4‐dichlorophenoxyacetic acid (2,4‐D). Variations including leaf shape, plant height, flower number per cluster, fruit shape, anther number per flower and pollen fertility were compared among ≅ 300 plants (R0). Although these variations were confirmed among plants regenerated using both auxins, the frequencies of somaclonal variations in leaf shape, plant height, fruit shape and pollen fertility in the NAA experiment were higher than those in the 2,4‐D experiment. Variations in flower number and anther number were also confirmed among plants from both experiments, although no significant differences in their frequency were observed. Subsequently, the inheritance of variations (leaf shape, fruit shape, and flower number) observed in R0 was investigated from generation to generation (R1). Variations in leaf shape and fruit shape were inherited while those in flower number were not. From these results we concluded that, although a high frequency of somaclonal variations were observed among plants from both methods, embryogenesis with NAA was more efficient than 2,4‐D in eggplant.
Pollen storage at low temperature as a procedure for the improvement of cold tolerance in spring rape, Brassica napus L.
Authors: Lyakh V. A. , Soroka A. I. , Kalinova M. G. 
Published: April 2006

AbstractThe possibility of selecting spring rape for cold tolerance at the mature pollen grain stage was studied by investigating the effects of pollen storage at low temperatures on the quality of pollen grains and on the cold tolerance of the plants generated from them. Pollen treatments of F1 hybrids affected fertilization ability much more than viability and even after 10 days storage at 3 or 10°C the pollen germination percentage was reasonably high. Pollen storage for 7 or 10 days at 3 or 10°C significantly increased the cold tolerance of F2 seed germination, with 3°C being more effective. Pollen storage for a shorter time had no effect upon the number of resulting genotypes tolerant to low temperature. This approach may be successfully applied in plant breeding to enrich segregating plant populations with cold‐tolerant genotypes.
AMMI analysis of rainfed lowland rice (Oryza sativa) trials in Nigeria
Authors: Abamu F. J. , Alluri K. 
Published: April 2006

AbstractThe additive main effects and multiplicative interaction (AMMI) model is used to analyse the grain yield data of 13 rice genotypes grown in 12 rainfed lowland rice environments. The trials were organized by the International Network for Genetic Evaluation of Rice in Africa (INGER‐Africa) and conducted in Nigeria. Main effects due to environments (E), genotypes (G) and G × E interaction were found to be significant (P = 0.001). Cross validation analysis suggested that an AMMI model with one interaction principal component axis (IPCA) was most useful predictively, whereas Gollobs’ test declared two components, IPCA1 and IPCA2, statistically significant (P = 0.01). The IPCAl, however, accounted for most (47.8%) of the G × E sum of squares. Correlation and regression analysis, and relative scatter of genotype and environment points on the AMMI biplot suggest that the interaction partitioned in IPCA1 resulted from differences in the days to flowering among the genotypes. The paper discusses these in relation to the occurrence of Fe toxicity at the test sites and varietal tolerance to the stress.
Tetralocular mustard, Brassica juncea: New promising variability through interspecific hybridization
Authors: Katiyar R. K. , Chamola R. , Chopra V. L. 
Published: April 2006

AbstractLines of Brassica juncea with tetralocular (four‐valved) pods were produced by interspecific hybridization between dilocular (two‐valved) B. juncea var. Pusa Barani and tetralocular yellow‐seeded turnip rape (Brassica rapa ssp. trilocularis) var. YID‐1. Some selected lines were significantly superior to their parents for some agronomic traits, including seed yield and harvest index. Line 11 was the best among these and recorded 70% yield advantage in plot yield.
Genetic mapping of sedimentation volume across environments using recombinant inbred lines of durum wheat
Authors: Blanco A. , Bellomo M. P. , Lotti C. , Maniglio T. , Pasqualone A. , Simeone R. , Troccoli A. , Di Fonzo N. 
Published: April 2006

AbstractSDS‐sedimentation volume (SV) is a biochemical index widely used to evaluate flour quality in durum and bread wheats. Significant association between SV and endosperm proteins (gliadin, high‐molecular‐weight‐ and low‐molecular‐weight‐glutenin subunits) have been reported. Protein loci, however, account for only a portion of the total genetic variability. The objective of this study was to identify and locate quantitative trait loci (QTLs) associated with SV in a set of recombinant inbred (RI) lines, derived from a cross between the cv.‘Messapia’ of durum wheat and the accession MG4343 of the var. dicoccoides, and characterized for 259 genetic and molecular (RFLP) markers. Significant differences were detected for the quality index in the six environments examined, while the pattern of variability was that of a quantitative trait. Regression analysis of marker loci and sedimentation volume indicated, as expected, that chromosome 1B, on which are located the Gli‐B 1/Glu‐B 3 loci for some gliadin and glutenin subunits, is important for wheat quality. Two additional regions located on chromosomes 6AL and 7BS, and four regions on 1AL, 3AS, 3BL and 5AL, were shown to have single‐factor effects on sedimentation volume at P < 0.001 and P < 0.01, respectively. Positive effects were contributed by both parents. A multiple linear regression model consisting of seven significant loci on different chromosomes explained 62–91% of the genotypic variation of the trait. The availability of linked markers to QTLs may facilitate the genetic dissection of quantitative traits and the early selection in wheat breeding programmes.
Genetic variation of β‐amylase thermostability among varieties of barley, Hordeum vulgare L., and relation to malting quality
Authors: Kihara M. , Kaneko T. , Ito K. 
Published: April 2006

AbstractTo investigate variation in the thermostability of β‐amylase among varieties of barley, Hordeum vulgare L., crude enzyme was extracted from the seeds, and the relative remaining activity was calculated after heat treatment. Our results indicated that the varieties tested were divided into three groups (types A, B and C). All the latest Japanese malting varieties showed high themostability (type A), while European, North American and Australian varieties showed intermediate (type B) or low thermostability (type C). Isoelectric focusing (IEF) of β‐amylase was also investigated. Type B varieties divided into two subtypes (types B1 and B2) based on two different IEF patterns (types I and II), whereas those of types A and C showed only one IEF pattern (type II). We also examined their thermostability in the varieties based on the pedigrees of the Japanese malting barley. Our results indicated that the thermostability of β‐amylase had a close relationship to fermentability for the production of beer. This fact suggests that the thermostability of β‐amylase has a significant influence on the malting quality of barley.
Genotypic variation for in vitro criteria and relationships with in vivo digestibility in forage maize hybrids
Authors: Argillier O. , Barrière Y. , Dardenne P. , Emile J. C. , Hébert Y. 
Published: April 2006

AbstractThe aim of this work was to study the genotypic variation for in vitro digestibility and composition traits within maize elite hybrids, and their relationships with in vivo digestibility traits. Experiments using 58 maize hybrids were carried out in four French environments in 1995. Near‐infrared reflectance spectroscopy (NIRS) was used to determine in vitro digestibility (whole‐plant and cell‐wall digestibility) and biochemical composition (starch, soluble carbohydrates, neutral detergent fibre, acid detergent lignin, protein and ash contents). The 58 hybrids were also studied at INRA, Lusignan, France, within a long‐term experiment to determine their in vivo digestibility of organic matter and of crude fibre using standard sheep. Genotypic variation was studied and relationships between hybrid mean values for in vitro parameters and in vivo digestibilities were examined. For evaluation and breeding purposes, it is possible to discriminate maize elite hybrids according to their digestibility, especially for discarding low‐value genotypes. in vitro parameters, such as in vitro whole‐plant digestibility and cell‐wall digestibility associated with cell‐wall content, can be routinely investigated with NIRS. Accurate criteria that are satisfactorily relevant to reference data of in vivo digestibility evaluated with standard sheep can be obtained to explain about 60% of the variation.
Anther culture response of wild Oryza species
Authors: Tang K. , Sun X. , He Y. , Zhang Z. 
Published: April 2006

AbstractThirteen different wild species of the genus Oryza were investigated for their response to anther culture and plant regeneration. Callus induction from microspores of anthers was found to be strongly dependent on the species. Although large numbers of anthers from wild Oryza species, including O. barthii, O. latifolia, O. australiensis, O. minuta, O. nivara, O. paraguagensis and O. eichingeri, were cultured, no calli could be obtained. However, calli were produced from anthers of O. punctata, O. perennis, O. alta, O. ridleyi and O. rufipogon, although the frequency of callus induction was different. Similar species‐dependence was observed in plant regeneration from microspore‐derived calli. In total, 62 plants were derived from anther culture, including 47 albino and 15 green plants (of which 26.7% were haploids) from O. perennis; for the first time, six albino plants were obtained from O. ridleyi. Phytohormone combinations in the callus induction medium were found to influence callus induction and different wild Oryza species exhibited their own preferred phytohormone combinations for anther culture. In general, NK medium containing suitable concentrations of auxin and cytokinin may be successfully applied for anther culture of selected wild Oryza species.
Genomic structure of androgenic progeny of pentaploid hybrids, Festuca arundinacea × Lolium multiflorum
Authors: Zwierzykowski Z. , Lukaszewski A. J. , Lesniewska A. , Naganowska B. 
Published: April 2006

AbstractTo assess the usefulness of the doubled haploid (DH) method in the breeding of forage grasses, a sample of anther‐derived progeny of pentaploid F1 hybrids of Festuca arundinacea × Lolium multifiorum was karyotyped using genomic in situ hybridization (GISH). The technique allowed scoring of the total number of chromosomes, the number of chromosomes contributed by each parent, and the number and positions of the Festuca‐Lolium translocation breakpoints. Among 27 plants analysed, 13 belonged to three clones, effectively reducing the number of different progeny karyotyped to 17. These included 10 haploids, five doubled haploids and two plants for which the origins could not be explained. In all plants analysed, a mixture of chromosomes of both parents was present, including an average of 1.88 intergeneric translocations per plant. The translocation breakpoints were distributed along almost the entire length of the chromosome arms. Chromosome variation among androgenic progeny appeared much wider than that in the conventional backcross but low vigour and high mortality suggest that this additional variation may be difficult to exploit directly in breeding. However, a change in the pattern of recombination makes the entire genome accessible to manipulation.
High frequency of plant regeneration from anther culture in flax, Linum usitatissimum L.
Authors: Chen Y. , Kenaschuk E. , Dribnenki P. 
Published: April 2006

AbstractThe effects of induction medium compositions on flax anther culture were investigated in order to improve the efficiency of callus induction and plant regeneration. Anthers were inoculated onto the modified MS medium supplemented with five different combinations of plant growth regulators. The medium containing the combination of 2mg/l 2,4‐ dichlorophenoxy‐acetic acid (2,4‐D) and 1 mg/1 6‐benzylaminopurine (BAP) produced a significantly higher number of calli forming shoots/100 responded anthers and a significant increase in overall efficiency of regeneration than the same basal medium containing 1 mg/1 a‐naphthalene‐acetic acid (NAA) and 2 mg/1 BAP (CK). Among the five levels of thiamin hydrochloride tested, the modified MS medium containing 10 mg/1 thiamin hydrochloride significantly increased the number of calli forming shoots/100 responded anthers and the overall efficiency of regeneration compared with the same basal medium containing 0.1 mg/1 thiamin hydrochloride. Maltose concentration had a significant effect on the percentage of anthers producing call, the number of calli forming shoots/100 responded anthers and the overall efficiency of regeneration. The medium containing 6% or 9% maltose produced the highest overall efficiency of regeneration among the five levels of maltose evaluated. Sucrose concentration significantly affected the number of calli forming shoots/100 responded anthers and the overall efficiency of regeneration, and dramatically affected the frequency of microspore‐derived plants and the frequency of spontaneous chromosome doubling in microspore‐derived plants. The efficiency of doubled haploid line production obtained in this study appears adequate for applied breeding programmes.
Multiple changes in tobacco mitochondrial DNA populations during tissue culture
Authors: KANAZAWA A. 
Published: April 2006

AbstractChanges in the composition of mitochondrial DNA (mtDNA) in tobacco during the processes of long‐term tissue culture and regeneration were detected by DNA gel blot analyses using several mtDNA fragments as probes. The changes in mtDNA were identified by differential accumulations of mtDNA fragments in cultured cells that were hybridized with probes atp6, cob, and nad3‐rpsl2. The changes detected by each probe did not appear to be linked, since they were different with each probe and in different subcultures of calli. Based on the current results and previous detailed analyses of the changes detected by atp6, a possible model that explains the alterations in mtDNA during tissue culture is presented. In this model, the changes are attributed to multiple shifts in the equilibrium that was maintained between different subgenomic mtDNA molecules.
Genetic diversity in mung bean germplasm revealed by RAPD markers
Authors: SANTALLA M. , POWER J. B. , DAVEY M. R. 
Published: April 2006

AbstractKnowledge of the genetic relationships among landraces is useful to gene bank managers because it permits a better organization of the crop's gene pool management, more efficient sampling of the available germplasm resources and better access to useful genetic variation for breeders. Genetic diversity of 19 landraces of the cultivated mung bean, Vigna radiate, and three weedy and wild relatives including Vigna mungo, Vigna luteola and Vigna radiate var. sublobata, was investigated at the DNA level with the random amplified polymorphic DNA (RAPD) procedure. Sixty random decamer primers were employed in amplification reactions; 28 of these were informative and yielded 246 bands, of which 229 were polymorphic with a mean of 8.2 bands per primer. A genetic distance matrix based on Nei and Li coefficient was converted to a dendrogram and a two‐dimensional plot using multidimensional scaling (MDS). The accessions studied were separated into three main clusters, which included V. radiate landraces, V. mungo and V. luteola, respectively. The variation of this cluster supports the view that the genetic distance of V. mungo and V. luteola varies considerably from the accession VO2955 (V. radiata). The multidimensional scaling plot confirmed that V. mungo, V. luteola and most of the accessions of V. radiata formed distinct clusters with no overlap, and two mung bean accessions (PI177493 and VO4134–1 from Turkey and India, respectively) were genetically distant from other V. radiata landraces. V. radiata and V. mungo are positioned in separate botanical species and V. radiata var. sublobata is classified within other V. radiata landraces. Based on the limited range of accessions tested, the approach holds promise for the classification of mung bean germplasm, identification of mung bean landraces and applications of molecular markers to mung bean breeding.
Production of diploid and triploid interspecific hybrids between Lilium concolor and L. longiflorum by in vitro ovary slice culture
Authors: Arzate‐Fernández A.‐M. , Nakazaki T. , Tanisaka T. 
Published: April 2006

AbstractSuccessful hybridization between Lilium concolor and Lilium longiflorum has not been reported but ovary slice culture technique, after cut‐style pollination has now been used to produce diploid and triploid interspecific hybrids between these species. Reciprocal crosses between diploid cultivars (2n= 2x= 24) were conducted. 5, 10, 15, 20, 25, 30, 35, 40, and 45 days after pollination (DAP), ovaries were sliced and cultured on a modified Murashige and Skoog (MS) medium without growth regulators and NH4NO3, supplemented with 6% sucrose, 50 mg/1 yeast extract and 0.25% gelrite at pH 6.3. For the L. concolor × L. longiflorum cross, embryo germination was found to be best at 20 DAP, while for the L. longiflorum × L. concolor at 25 DAP. After transfer to a MS (half‐strength) medium supplemented with 1.5% sucrose, 0.25% gelrite and 0.2% active charcoal at pH 5.8, diploid and triploid hybrid plants were developed. All regenerated plants were identified as hybrids on the basis of karyotype and isozyme analyses. Ovary slice culture technique as a method of producing polyploids is discussed.