bluuebunny/crossref_metadata_2025_split huggingface dataset:
Combining Ability for Resistance to Field Aflatoxin Accumulation in Maize Grain*
Authors: Gorman D. P. , Kang M. S. , Cleveland T. , Hutchinson R. L. 
Published: April 2006

AbstractPrevious genetic studies on resistance to aflatoxin production in maize (Zea mays L.) only used a limited amount of germplasm. The objective of this study was to determine general (GCA) and specific combining abilities (SCA) for resistance to prehar‐vest aflatoxin accumulation in grain, utilizing A619 Lfy syn, A632 Lfy syn, B73 Lfy syn, Hy Lfy syn, Mol7 Lfy syn, Wf9 Lfy syn, and 914 Lfy syn. We evaluated 21 F1 crosses (diallel) for aflatoxin accumulation in grain in three environments. Twenty‐one days after mid‐silk, ears were slash‐inoculated with Aspergillus parasiticus (Speare). Samples were analyzed for aflatoxins Bl B2, G1 and G2. Significant differences for aflatoxin accumulation were detected among environments, with the environment that experienced drought stress showing the highest concentration for all four aflatoxins. The GCA and crosses mean squares were not significant for any aflatoxin and the SCA mean square was significant (P = 0.1) only for aflatoxin G2. Relatively small quantities of aflatoxin accumulation on, and nonsignificant differences among the 21 F1 crosses might be indicative of their inherently high resistance levels. The SCA sums of squares constituted two thirds or more of crosses sums of squares, which indicated a preponderance of dominance and/or epistatic effects for aflatoxin accumulation. The Hy Lfy syn GCA effect tended to increase aflatoxin Bl and Wf9 Lfy syn tended to reduce aflatoxin accumulation as it showed a significant (P = 0.1), negative GCA effect for aflatoxin G1. The F1 cross Wf9 Lfy syn × 914 Lfysyn showed significant, negative SCA effect for af‐latoxins B1 and G1, whereas A619 Lfy syn × 914 Lfy syn and Mo17 Lfy syn × Wf9 Lfy syn tended to increase one or more aflatoxins. For aflatoxin Br, a significant environments (E) × crosses (C) interaction was largely due to E × GCA interaction, which, in turn, was due to an interaction of the B73 Lfy syn GCA effect with E. This interaction effect tended to reduce aflatoxin BS. The E × C interaction for aflatoxin G2 was due to both E × GCA and E × SCA interactions. B73 Lfy syn GCA × E tended to reduce aflatoxin G, and Mo17 Lfy syn GCA × E tended to increase aflatoxin G. Additive genetic correlations based on GCA effects among the four aflatoxins were significant (0.76 to 0.96), except the correlation between aflatoxins B, and G2 (0.43), suggesting that, in general, increasing resistance to one toxin may lead to resistance to the other three toxins.
Reproductive Deterioration in Buckwheat (Fagopyrum esculentum) under Summer Conditions
Authors: Guan L. M. , Adachi T. 
Published: April 2006

AbstractTo resolve the problem of low and unstable yield in buckwheat under unsuitable environmental conditions, five varieties were grown and compared in summer and autumn. Vegetative and reproductive growth characteristics were investigated, and embryo development was observed with Nomarski's differential interference contrast (DIG) microscopy. In summer, under high temperatures and longer day‐length, autumn‐type varieties showed faster vegetative growth and later reproductive development as compared to summer‐types. In the autumn, with generally good climatic condition for buckwheat growth in southern part of Japan, the embryo sacs and zygotes of both types developed normally. At 3 days after pollination (DAP), the embryos reached the globular stage. In summer, however, mostly abnormal embryo sacs were observed 3 DAP, leading to incomplete development, failure of fertilization or abortion of embryo. The abnormal embryo sacs were classified into 6 types. Abnormality of either type occurred in 91—100 % of the tetraploids, which is higher than in the diploids (50—77 %). The present study, conducted to clarify the factors causing low seed set in buckwheat under summer conditions, provides detailed information for further breeding of environment‐tolerant buckwheat. Di‐ploid genotypes which are less sensitive to unfavourable conditions and, thus, show more efficient fertilization in summer, should be considered for use as breeding material in buckwheat.
The Concept of Varietal Ability for Partially Allogamous Crops
Authors: Link W. , Ederer W. 
Published: April 2006

AbstractGeneral (GVA) and specific (SVA) varietal ability quantify the value of genetic stocks as components for synthetic varieties. Additionally, these parameters can be used to predict the performance of the synthetics. The concept of varietal ability is known for completely allogamous crops. It has not yet been worked out for partial allogamy with a genotype‐dependent degree of cross‐fertilization. We have developed formulae to calculate GVA and SVA referring to generation Syn 1 in this general situation. The concept of varietal ability considers the influence of the components' per se performance on the resulting synthetic variety. This influence increases with decreasing degree of cross‐fertilization. Thus, our formulae should be of special benefit to partially allogamous crops.The formulae are illustrated by a numerical example taken from our research on Vicia faba L. To estimate the relevant parameters for Vicia fabe L., we propose to use two morphological markers (flowers and seed colour) simultaneously.
Influence of Different Cytoplasms and Nuclear Genes Involved in the cms System of Chives (Allium schoenoprasum L.) on Microsporogenesis
Authors: Ruge Brigitte , Potz Heidi , Tatlioglu T. 
Published: April 2006

AbstractMicrosporogenesis of different, temperature‐ and tetracycline‐sensitive cms plants, and male fertile genotypes was investigated.The microsporogenesis of cms plants [(S)xx] and fertile plants [(N)xx or (S)X.] is similar up to the tetrade stage. During the tetrade stage, microspores of cms plants start to die off. The effect of the (S)‐cytoplasm on microsporogenesis is overcome by the restorer gene X, the temperature gene T and by tetracycline gene a. Whereas the X gene acts independently of environmental conditions, the gene T is expressed at constantly high temperature of 24 °C, and the tetracycline gene a acts after tetracycline treatment. After temperature‐ and tetracycline treatment, respectively, the sensitive genotypes need 10—14 days to change from male sterile into male fertile. This period seems to be most interesting to study the influence of the defined nuclear genes on mitochondrial transcription and translation.
Graphical Genotype of Maize Inbred B86 Revealed by RFLPs
Authors: Fahr S. , Messmer M. M. , Melchinger A. E. , Lee M. , Woodman W. L. 
Published: April 2006

AbstractThe objective of this study was to investigate the origin of chromosome segments of maize (Zea mays L.) inbred B86 from its parental inbreds B52 and Oh43 using RFLPS. B86 was selected to combine resistance to the first and second brood of the European corn borer with the favorable agronomic performance of Oh43. RFLP analyses of the three inbreds were performed with three restriction enzymes (EcoRI, EcoRV, HindIII) and 178 DNA probes covering all ten maize chromosomes. For two DNA probes in combination with one enzyme, B86 showed a new RFLP pattern not present in the two parents. Based on results from 119 polymorphic DNA probes, the proportion of the B86 genome contributed by B52 (51.3 %) and Oh43 (48.7 %) was almost equal.
Anther Culture‐Derived Regenerants from Hordeum vulgare × H. bulbosum Crosses
Authors: Pickering R. A. , Fautrier A. G. 
Published: April 2006

Abstract Hordeum bulbosum has several desirable attributes, including disease resistance, which would be worthwhile transferring to H. vulgare. Despite homoeologous chromosome pairing in the interspecific hybrids, there have been few reports of successful gene introgression between the two species. A possible explanation for this is that recombinant male gametes are at a competitive disadvantage with normal balanced gametes during post‐pollination events. To circumvent this problem, the possibility of obtaining plants directly from immature pollen grains was investigated. Anthers from diploid, triploid and tetraploid H. vulgare × H. bulbosum hybrids were cultured on defined media. Only hybrids with dehiscent anthers in vivo responded in culture, and after transfer of calli and embryoids to regeneration medium, 36 albino and 12 green plants were obtained. Seven of the green regenerants survived, one of which contained 15 H. vulgare chromosomes (including one acrocentric chromosome) and one H. bulbosum chromosome. Another regenerant (Ac166) resembled a diploid H. vulgare × H. bulbosum hybrid but had partial anther dehiscence and a slightly modified chromosome constitution. Mostly normal H. vulgare progeny were obtained from crosses between H. vulgare cv.‘Emir’ and Ac166, but three plants involved chromosome additions and substitutions.
The Lack of a Relationship between Bitterness and Resistance of Cucurbits to Red Pumpkin Beetle (Aulacophora foveicollis)
Authors: Dhillon N. P. S. 
Published: April 2006

AbstractPurified cucurbitacin B and E act as feeding stimulants for the red pumpkin beetle, but on testing three pairs of isogenic bitter (Bi) and non‐bitter (bi) lines of cucumber, no relationship was found to exist between the bitter gene and the degree of damage caused by this beetle. In summer squash, both resistant and susceptible lines contain cucurbitacin at the susceptible plant growth stage (cotyledon) but there was no correlation between the quantity of total phenols, free amino acids or reducing sugars in this material and resistance. Bitter gourd, which has cucurbitacin in the cotyledons, was not preferred by the beetle.
Fertility Improvement in Autotetraploids of Pea — Selection for Seed‐Set and Disjunction Index
Authors: Kumar H. , Mercykutty V. C. , Srivastava C. P. 
Published: April 2006

AbstractFour seed‐set groups of plants, viz. unselected ‘general’ and selected ‘high’, ‘medium’ and ‘low’ were constituted in C1 generation from randomly selected autotetraploids of two pea cultivars, T 163 and 5064‐S. In C2 generation, ten plants were selected at random in each of the four groups. Two seeds each from selected autotetraploids were drawn and bulked to make 20 seeds in each of the four groups to raise C3 generation. Selection resulted in a gradual shift in seed‐set, though the magnitude and nature varied with the group and generation. Improvement in the seed‐set from C1 to C3 generation was associated with the increase in bivalents per cell, disjunction index and total chiasmata. Increase in total chiasmata was mostly due to an increase in proximal ones. Increase in seed‐set was reflected in improvement of grain yield per plant.
Chromosomal Location of Resistance to Septoria nodorum in a Synthetic Hexaploid Wheat Determined by the Study of Chromosomal Substitution Lines in ‘Chinese Spring’ Wheat
Authors: Nicholson P. , Rezanoor H. N. , Worland A. J. 
Published: April 2006

AbstractResistance to Septoria nodorum was investigated in seedlings of an amphiploid generated from Triticum dicoccum Shübl. and Aegilops squarrosa Tausch, and in a series of substitution lines of single chromosomes from this synthetic hexaploid into Triticum aestivum cv. ‘Chinese Spring’ in three tests to determine the chromosomal location of resistance. From the Ae. squarrosa parent (D genome), chromosome 5D was found to confer a high level of resistance, reducing lesion cover to near that of the amphiploid in the three tests. Chromosomes 3D, and to a lesser extent, 7D were also found to confer significant resistance to the amphiploid. Three chromosomes, 2A, 3B and 5A, from the T. dicoccum parent (AB genomes) also conferred resistance but to a lesser extent than 7D. Two chromosomes, 2B and 2D, caused a significant decrease in resistance. ‘Chinese Spring’ may thus carry genes for resistance to S. nodorum on these chromosomes which are absent in the synthetic hexaploid.
A Rapid Screening Method for Testing the Resistance of Cotyledons to Downy Mildew in Brassica napus and B. campestris
Authors: Gröuntoft M. 
Published: April 2006

AbstractSeveral hundred breeding lines of summer and winter forms of turnip rape as well as winter rape, were sown on greenhouse tables filled with soil. A week later the cotyledons were artificially inoculated and covered with a plastic tunnel. Approximately two weeks later the average percentage of the wilted leaf area was estimated.The method is rapid and demands little labour. It is therefore suitable for testing large numbers of breeding lines. The response to Peronospora parasitica (Pers. ex Pers.) Fr. in the rape material varied from being highly susceptible to highly resistant. Only minor differences were detected between lines with high and low glucosinolate contents. All the turnip rape material had very high resistance to P. parasitica at the cotyledonous stage.
Effects of Interspecific Competition on the Inheritance of Quantitative Traits in White Clover *)
Authors: Hill J. 
Published: April 2006

AbstractAnalysis of a half diallel cross among four white clover cultivars, grown as monocultures and in mixtures (duocultures) with two separate perennial rye‐grass cultivars, confirmed that for stolon and leaf number a higher proportion of the genetic variance in duocultures was non‐additive. For canopy height and dry weight, however, this proportion was less affected by inter‐specific competition. An additive‐dominance model of gene action sufficed for all four characters in monocultures, but in duocultures epis‐tasis was just one of the factors complicating the genetic picture. This, coupled with short‐term reversals in the direction of dominance, merely illustrates the complexity of breeding white clover cultivars. Possible future developments in the breeding of white clover are discussed in the light of these results.
Inbreeding Depression and Other Genetic Effects in Populations of Maize Containing Highland Tropical Germplasm
Authors: Eagles H. A. , Hardacre A. K. 
Published: April 2006

AbstractA variety cross diallel of five populations of maize (Zea mays L.) was evaluated in a cool, temperate environment. Two of the parental populations were Corn Belt Dent synthetics (AS3 and BS22), one was developed from selected lines from a CIMMYT population developed for highland regions of the tropics and four Corn Belt Dent inbred lines (NZS3), and the other two had the pedigrees ‘Criollo de Toluca’× AS32 (NZS1) and ‘San Gerónimo’× BS222 (NZS2). ‘Criollo de Toluca’ is from the highlands of Mexico and ‘San Gerönimo’ is from the highlands of Peru. The objective was to study the influence of introgressing highland tropical germplasm into elite Corn Belt Dent synthetics on genetic effects, especially inbreeding depression, and to develop recommendations for the utilization of the introgressed populations.Inbreeding depression explained the greatest proportion of the variation among entries for grain yield, days to silking and plant height, but not for grain moisture at harvest and root lodging. For grain yield, NZS1, NZS2, and NZS3 had high levels of inbreeding depression and the difference between NZS1 and AS3 was statistically significant. High levels of root lodging were associated with NZS1 and high grain moisture at harvest with NZS2. These results indicate that a recurrent selection method, such as S1 selection, which effectively reduces inbreeding depression, should be used in early cycles of selection with introgressed populations containing highland tropical germplasm.
Effect of Abscisic Acid on Pollen Germination and Tube Growth of Maize Genotypes1
Authors: Frascaroli E. , Tuberosa R. 
Published: April 2006

AbstractAs a preliminary step to using gametophytic selection to obtain genotypes of maize, Zea mays L., differing for abscisic acid (ABA) content and/or sensitivity, the influence of ABA on the in vitro germination and tube growth of maize pollen and the presence of genetic variability for these traits was investigated. In a first experiment, pollen samples of three genotypes were germinated on substrates containing increasing amounts of ABA. Low ABA concentration (0.5 νM) significantly increased pollen germination and tube growth, while 500 νM ABA significantly decreased both traits, thus indicating that ABA can influence the growth of maize pollen in vitro. In a second experiment, eleven inbred lines were screened for the in vitro reactivity of their microgametophytes to ABA. The lines differed significantly for the response (% of control) of tube length, but not of pollen germination to ABA.
Segregation Analysis of Isozyme Markers on Isolated Microspore‐Derived Embryos in Brassica napus L.
Authors: Foisset N. , Delourme R. , Lugas M. O. , Renard M. 
Published: April 2006

AbstractThe segregation of isozyme genetic markers was studied on embryos arising from isolated microspore cultures in live rapeseed F1 hybrid genotypes. Out of the ten isozyme genes considered, live (Aco‐1, Aco‐3, Lp‐1, Pgm‐3, Tpi‐1) did not segregate according to expected Mendelian ratios in at least two F1 crosses. F2 plants, generated from the same hybrids, included in the analysis, were tree of segregation distortions. Linkage analysis between each segregating enzyme locus in each progeny revealed independance between these markers.In this paper, the results of the linkage analysis as well as the origins of the distortions are discussed. The existence of androgenic embryogenesis genes may be responsible for the abnormal segregations of the five isozyme genes.
Self‐Fertile Doubled Haploid Plants of Perennial Ryegrass (Lolium perenne L.)
Authors: Madsen S. , Olesen A. , Andersen S. B. 
Published: April 2006

AbstractThe self‐fertility of chromosome‐doubled haploid lines of perennial ryegrass and their first (I1) and second (I2) generation selfed offspring was studied. The overall seed set was low, 0—0.4 seeds per spike, as would be expected for chromosome‐doubled haploids of a self‐incompatible species. Nevertheless, significant genetic variation was observed for self‐fertility within three of the six lines studied. Within one line, three I2‐clones showed increased self‐fertility, while in two other lines one and three I1‐clones, respectively, showed significantly increased self‐fertility. Selection, during selfing, of rare pollen grains with mutations in the self‐incompatibility system could explain the observed changes and would lead to a general breakdown of self‐incompatibility in Lolium perenne during repeated selfing of chromosome‐doubled haploids.
Mutagenic Effects of Combined and Single Doses of Gamma Rays and EMS in Opium Poppy*
Authors: Chauhan S. P. , Patra N. K. 
Published: April 2006

AbstractMutagenic effects of gamma rays and EMS using both single and combined dosages were examined in opium poppy (Papaver somniferum L.). For inducing both macro‐ and micro‐mutations in the present study, combined mutagenic doses, especially 5 kR + 0.4 % EMS appeared to be greatly superior to all single doses of the two mutagens: gamma rays and EMS. The lowest dose of combined mutagen (5 kR + 0.2 % EMS) was about twenty times more effective than the most effective dose (15 kR) of gamma rays and twice as effective as the most effective concentration (0.4 %) of EMS. The combined dose 5 kR + 0.4 % EMS enhanced morphine content (%) to 0.98 as against 0.64 in the control. In accordance with earlier findings (GAUL 1964) the study revealed a correlation between induced macro‐ and micro‐mutations.
Genetic Variability of Rubisco in Tetraploid Wheats (Triticum turgidum)
Authors: Nicco C. , Sarrafi A. , Piquemal M. , Cavalie G. 
Published: April 2006

AbstractNineteen tetraploid wheats (Triticum turgidum), differing in their agronomical behaviour and geographic origins were grown in two experiments and analysed for the following physiological traits: soluble leaf protein content, rubisco content, initial and potential carboxylase activities of this enzyme as well as its relative content in percentage of protein, the specific activity of the enzyme and its activation state.The results show a high genetic variability for all studied traits and more particularly for the initial carboxylase activity. High phenotypic correlation was observed between the rubisco content and its potential activities, in the first experiment. Correlation between souble leaf protein and rubisco content was significant in 9 genotypes of the second experiment.
Protein Phosphorylation and Protein Patterns in Developing Endosperms of Barley
Authors: Yupsanis T. , Shewry P. R. 
Published: April 2006

AbstractThe SDS‐soluble protein‐fractions of barley endosperms (2 and 3 weeks after anthesis) were compared using 1‐D SDS‐PAGE and 2‐D IEF/SDS‐PAGE. Similar procedures have been followed after in vivo phosphorylation of isolated endosperm with 32PO4.Protein patterns were similar when 1‐D SDS‐PAGE was used. On the other hand, 2‐D IEF/SDS‐PAGE revealed several major differences, the most important being the appearance of a major protein of Mr about 40,000 in the 3‐weeks old endosperm. By contrast, the patterns of phosphorylated proteins, with both methods, were relatively simple. Only two phosphorylated bands showed up in the 3‐weeks old endosperm: a highly labelled band of Mr about 65,000, and a band of about 75,000. In the case of 2‐weeks old endosperm, where the phosphorylation was more active, these and several others were also labelled, but the Mr 75,000 band was labelled more intensely.
Milling Energy Polymorphism in Hordeum spontaneum Koch in Israel and its Potential Utilization in Breeding for Malting Quality
Authors: Ellis R. P. , Nevo E. , Beiles A. 
Published: April 2006

AbstractVariation for grain milling energy in Hordeum vulgare is associated with differences in grain size, shape and composition. Genetic polymorphisms within and between populations were found across the ecogeographical range of Hordeum spontaneum in Israel. Low milling energy estimates were positively correlated with and predictable by the aridity index. Milling energy in H. spontaneum, collected in Israel, ranged from the lowest values seen in making barley to twice the highest values seen in feed cultivars. It is concluded that H. spontaneum elite genotypes could be effectively identified by milling energy for use in the breeding of new cultivars.
Genetics of Panicle Exsertion in Cold‐Tolerant Rice (Oryza sativa)
Authors: Pandey D. K. , Gupta H. S. 
Published: April 2006

AbstractFour cold‐tolerant rice varieties, viz. ‘Khonorullo’, ‘Namyi’, ‘Abor B’ and ‘Meghalaya‐1’ were crossed with two cold‐susceptible ones, viz. ‘Pusa 33’ and ‘Subhadra’ (DR92), in all possible combinations to study the inheritance of gene(s) governing panicle exsertion and their allelic relationship among cold‐tolerant varieties. F1 hybrids of all the crosses showed complete panicle exsertion indicating dominance of this trait. Segregation pattern of panicle exsertion in F2 and backcrosses show that all the four cold‐tolerant varieties possessed a single dominant gene designated as Ctr‐1. Absence of segregation for panicle exsertion in an F2 generation obtained from intercrosses of cold‐tolerant varieties suggests that the dominant genes in all the four cultivars are allelic.