bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular characterization and expression analysis of a rice protein phosphatase 2C gene, OsBIPP2C1, and overexpression in transgenic tobacco conferred enhanced disease resistance and abiotic tolerance
Authors: Hu Xuebo , Song Fengming , Zheng Zhong
Published: April 2006

A full‐length cDNA of a rice protein phosphatase 2C gene, OsBIPP2C1, was cloned and identified. OsBIPP2C1 is predicted to encode a 569 amino acid protein that contains phosphatase domain at its C‐terminal and a relatively long N‐terminal extension. Expression profiles of OsBIPP2C1 in rice seedlings upon treatments with disease resistance inducers, pathogen infection, and mechanical wounding as well as various environmental stress conditions were analyzed. Expression of OsBIPP2C1 was activated upon treatments with benzothiadiazole (BTH), salicylic acid, and hydrogen peroxide, which are signal molecules in plant disease resistance responses, and was induced during the first 48 h after inoculation with Magnaporthe grisea in BTH‐treated rice seedlings. OsBIPP2C1 was also upregulated upon mechanical wounding and treatments with abscisic acid, high salt, low temperature, and drought stress. Transgenic tobacco plants overexpressing OsBIPP2C1 gene showed enhanced disease resistance against tobacco mosaic virus and Phytophthora paratisca and increased tolerance against salt and osmotic stresses. These results suggest that OsBIPP2C1 may play important roles in responses to biotic and abiotic stresses.
Freezing and desiccation tolerance of imbibed canola seed
Authors: Gusta Lawrence V. , Gao Yong‐Ping , Benning Nicole T.
Published: April 2006

Depending on the environmental conditions, imbibed seeds survive subzero temperatures either by supercooling or by tolerating freezing‐induced desiccation. We investigated what the predominant survival mechanism is in freezing canola (Brassica napus cv. Quest) and concluded that it depends on the cooling rate. Seeds cooled at 3°C h−1 or faster supercooled, whereas seeds cooled over a 4‐day period to −12°C and then cooled at 3°C h−1 to−40°C did not display low temperature exotherms. Both differential thermal analysis and nuclear magnetic resonance (NMR) spectroscopy confirmed that imbibed canola seeds undergo freezing‐induced desiccation at slow cooling rates. The freezing tolerance of imbibed canola seed (LT50) was determined by slowly cooling to −12°C for 48 h, followed with cooling at 3°C h−1 to −40°C, or by holding at a constant −6°C (LD50). For both tests, the loss in freezing tolerance of imbibed seeds was a function of time and temperature of imbibition. Freezing tolerance was rapidly lost after radicle emergence. Seeds imbibed in 100 μM abscisic acid (ABA), particularly at 2°C, lost freezing tolerance at a slower rate compared with water‐imbibed seeds. Seeds imbibed in water either at 23°C for 16 h, or 8°C for 6 days, or 2°C for 6 days were not germinable after storage at −6°C for 10 days. Seeds imbibed in ABA at 23°C for 24 h, or 8°C for 8 days, or 2°C for 15 days were highly germinable after 40 days at a constant −6°C. Desiccation injury induced at a high temperature (60°C), as with injury induced by freezing, was found to be a function of imbibition temperature and time.
Drought acclimation confers oxidative stress tolerance by inducing co‐ordinated antioxidant defense at cellular and subcellular level in leaves of wheat seedlings
Authors: Selote Devarshi S. , Khanna‐Chopra Renu
Published: April 2006

Wheat (Triticum aestivum L.) seedlings of a drought‐resistant cv. C306 were subjected to severe water deficit directly or through stress cycles of increasing intensity with intermittent recovery periods (drought acclimation). The antioxidant defense in terms of redox metabolites and enzymes in leaf cells, chloroplasts, and mitochondria was examined in relation to ROS‐induced membrane damage. Drought‐acclimated seedlings modulated growth by maintaining favorable turgor potential and RWC and were able to limit H2O2 accumulation and membrane damage as compared with non‐acclimated plants during severe water stress conditions. This was due to systematic upregulation of H2O2‐metabolizing enzymes especially ascorbate peroxidase (APX, EC 1.11.1.11) and by maintaining ascorbate–glutathione redox pool in acclimated plants. By contrast, failure in the induction of APX and ascorbate–glutathione cycle enzymes makes the chloroplast susceptible to oxidative stress in non‐acclimated plants. Non‐acclimated plants protected the leaf mitochondria from oxidative stress by upregulating superoxide dismutase (SOD, EC 1.15.1.1), APX, and glutathione reductase (GR, EC 1.6.4.2) activities. Rewatering led to rapid enhancement in all the antioxidant defense components in non‐acclimated plants, which suggested that the excess levels of H2O2 during severe water stress conditions might have inhibited or downregulated the antioxidant enzymes. Hence, drought acclimation conferred enhanced oxidative stress tolerance by well‐co‐ordinated induction of antioxidant defense both at the chloroplast and at the mitochondrial level.
Variation in Phenotype and Chromosome Number of Plants Regenerated from Protoplasts of Dihaploid and Tetraploid Potato
Authors: Sref Ramulu K. , Dijkhuis P. , Roest S. , Bokelmann G. S. , de Groot B.
Published: April 2006

An investigation was made on the origin and basis of somaclonal variation in potato. Plants were regenerated from protoplasts of dihaploid and tetraploid potato, and the degree of variation in phenotype and chromosome number was analysed. All the regenerants from dihaploid potato showed variation in chromosome number, while only part of these varied in plant morphology. In tetraploid potato, 60 % of the regenerants showed variation in chromosome number, all of which exhibited phenotypic changes. The data suggest that the explant source and the initial ploidy level of the genotype play an important role in influencing the degree of somaclonal variation.
Diallel Analysis of Grain Yield in Barley Using Doubled‐Haploid Lines*
Authors: Choo T. M. , Kotecha A. , Reinbergs E. , Song L. S. P. , Ffjer S. O.
Published: April 2006

Grain yields of seven barley cultivars (Hordeum vulgareL.) and 398 doubled‐haploid lines derived from their diallel crosses were evaluated in hill plots at two locations in Ontario. Additive × additive epistasis and linkage disequilibrium were detected in the seven cultivars. Additive × additive genetic variance was significantly greater than zero but additive genetic variance was not significantly greater than zero. The narrow‐sense heritability on the basis of line means was intermediate (0.33). It was predicted that 13.1% yield improvement could be realized in the next recurrent selection cycle using the doubled‐haploid method.
Comparison of Spring Barley Lines Produced by Single Seed Descent, Pedigree Inbreeding and Doubled Haploidy
Authors: Powell W. , Caligari P. D. S. , Thomas W. T. B.
Published: April 2006

Samples of inbred lines of Hordeum vulgare produced by pedigree inbreeding, doubled haploidy and single seed descent have been compared for a range of agronomic characters. Differences between the means of the in bred s produced by single seed descent and pedigree breeding were due to differing levels of inbreeding. The present study confirmed chat recombinant inbred families which out‐perform the higher scoring parent may be produced by either method. Caution should, however, be exercised when simply inherited characters controlled by major genes are fixed in early generations. Differences between the doubled haploid and single seed descent samples for the character thousand grain weight were attributable to coupling linkages involving epistatic genes. The production and evaluation of random inbred lines should be considered as an alternative to pedigree methods of barley breeding.
Patterns of Diversity of Ethiopian Wheats (Triticum spp.) and a Gene Center for Quality Breeding
Authors: Negassa M.
Published: April 2006

A collection consisting of 293 entries of tetraploid and hexaploid Ethiopian wheat was investigated for diversity of endosperm texture, seed color, kernel texture, flour color, gluten quality, seed size, and protein content. All characters, except gluten quality, showed high levels of diversity‐ Significant differences in protein content and gluten quality occurred among districts, and among provinces. Regional differences were also observed for seed size and flour color. The average estimate of diversity of these characters for Ethiopia was high (H̄= 0.77). Some of the characters showed clinal variations, and others, localized concentrations. Entries with combinations of good quality characters were observed, and their possible use as source materials in wheat breeding is discussed. A gene center for quality breeding was identified in Southern Ethiopia, and the participation of centers of diversity in the evaluation and utilization of genetic resources is considered as a very important tool in genetic conservation.
Potential for Incorporation of Early and Late Leafspot Resistance in Peanut*
Authors: Anderson W. F. , Wynne J. C. , Green C. C.
Published: April 2006

A detached leaf technique was used to evaluate components of resistance to both early and late leafspot caused by Cercospora arachidicola Hori and Cercosporidium personatum (Berk, and Curt.) Deighton, respectively, for F2 plants of two peanut (Arachis hypogaea L.) crosses (FESR 5‐P2‐B1 /PI 269685 and PI 35068Q/GP‐NC 343), No negative correlations were obtained when comparing components of resistance to early leafspot with components of resistance to late leafspot, indicating that the resistances are inherited independently. A small number of F2 plants had greater partial resistance to both leafspots than their parents when evaluated by an index including percent necrotic area, latent period and sporulation. Broad sense heritabilities of resistance components were moderate to high (0.4 to 0.8) for the F2 populations. A visual sporulation rating scale was significantly correlated (0.8 to 0.9) with conidia per lesion and conidia per necrotic area. The data suggest that peanut cultivars resistant to both leafspots can be developed.
Autofertility and Bee Visitation in Winter and Spring Genotypes of Faba Beans (Vicia faba L.)
Authors: Stoddard F. L.
Published: April 2006

Differences in the expression of autofertility and in the evidence of attractiveness to bees were investigated in both autumn‐sown and spring‐sown faba beans. All six winter stocks and one spring stock expressed very little autofertility, with averages of only 10% of flowers and 7% of ovules fertilized when undisturbed. Three other spring stocks, including a closed‐flower population, were moderately autofertile, with 22% of flowers and 17% of ovules fertilized when undisturbed. The remaining two spring stocks, both English cultivars, expressed good autofertility, with 50% of undisturbed flowers and 44% of ovules fertilized. Current levels of autofertility in the winter and closed‐flower stocks were inadequate to allow the development of a desirable distribution of pods without substantial bee visitation. If levels of autofertility could be raised simply by selection within populations, then they should have been much higher in these stocks. Therefore, autofertile parents will probably have to be included in programmes for breeding cultivars with improved levels of auto fertility.

The closed‐flower population received significantly less bee visitation than the other stocks in the spring trial. No variation in attractiveness to bees was found among the open‐flowered spring stocks, nor among the winter stocks.
Pollination, Fertilization and Seed Development in Inbred Lines and F1 Hybrids of Spring Faba Beans (Vicia faba L.)
Authors: Stoddard F. L.
Published: April 2006

When the flowers are not disturbed, the yield of F1 hybrids of faba beans normally exceeds that in their inbred parents. The basis of this “heterotic autofertility” was investigated by examining flowers for pollination and fertilization throughout the flowering season and assessing the distribution of seeds and pods on mature plants. Six inbred lines and seven of their F1 hybrids were grown without protection from bee visitation, and their autofertility was estimated’ by comparing their fertilization with that of cytoplasmic male‐sterile line. The first direct evidence was obtained that heterotic autofertility acts by increasing; the proportion of flowers which were pollinated and fertilized. The autofertility was not perfect, especially in a closed‐flower hybrid, as many ovules remained unfertilized. Several factors contributed to the number of seeds per pod in F1 hybrids, being superior to parental means: (1) more ovules per flower, (2) greater fertilization of the basal ovules, (3) reduced abortion of the apical ovules and (4) greater overall maturation ovules.
Changes in Several Traits of Oats Caused by Selection for Vegetative Growth Rate*
Authors: Gupta S. C. , Frey K. J. , Cox D. J.
Published: April 2006

Growth rate and harvest index are the primary components that cause variation in gram yield or oats it growth duration of the crop is fixed as it is in mid western USA. Because harvest index for oats in that region has been optimized 45 %, growth rate is the only remaining trait for improving grain yield.

F2 derived oat lines from inter‐ (Avena sativa L. ×A. Sterilis L.) and intraspecific mating (among A. sativa cultivars) in F3 were selected for vegetative growth rate at maturity (GRM) with an intensity of 8.3%. Predicted genetic gain was 21.5% for GRM, and actual gain was 7%. Changes in grain, biological, and straw yields were higher than gains in GRM when expressed as percentages of the oat population means. Predicted genetic gains were very low for traits unrelated or negatively associated with GRM such as heading data and harvest index. This study suggests that indirect improvement can be made for gain, biological, and straw yields by selecting for GRM.
Heritability and Correlation Studies on Some Vegetative Traits in Nigerian Local White Onion, Allium cepa L.
Authors: Kadams A. M. , Nwasike C. C
Published: April 2006

Heritability estimates for soluble solids, bulb firmness and bulb weight were carried out in two ways, namely, parent‐offspring regression and half‐sib family intra‐class correlation. Leaf characters were estimated only by half‐sib intra‐class correlations. For soluble solids the values were high (72% and 58% respectively), while the values for bulb weight And bulb firmness were low (20% and 39%, and 32%, and 33% respectively) using the two methods. Some high additive genetic correlations were observed between bulb firmness and length of longest leaf (rA= 0.830), bulb weight and leaf area of longest leaf (rA= 0.704).
Investigations on Seedling Vigour in Cashew (Anacardium occidentale L.)
Authors: Faluyi M. A.
Published: April 2006

Seedlings from 27 open pollinated cas‐hew genotypes in two environments with five replications in each location were used to investigate the genetic, the environmental, and the nut size effects on cashew seedling vigour during the 12‐week pretransplantation period.

Enviromental variances, genotype × environment interactions, and broadsense heritability values for the eight studied traits indicated that emergence percentage (L %) and seedling height (SH) were more reliable indices for seedling vigour, since they were more heritable and less influenced by the environment. Seedlings from large cashew nuts were consistently more vigorous than those from small nuts, probably because of the larger food reserve in the two cotyledons.
Callus Production and Plant Regeneration from Mature Embryos of Poa pratensis L.
Authors: Boyd L. A. , Dale P. J.
Published: April 2006

Plant regeneration from callus cultures may provide a source ot somaclonal variation for the improvement ot the apomictic grass Poa pratensis L. It is first necessary to be able to induce callus and regenerate plants in this species at a high frequency. Variation was observed between 50 cutivars of Poa pratensis for callus induction and plant regeneration. Using the cultivars ‘Merion’ and ‘Victa’, three basal media were tested along with various media additives. Murashige and Skoog's basal medium with 0.2 mg 1−1 2,4‐dichlorophenoxyacetic acid, 0.1 mg 1−1 6‐benzylamanopurine, 100 mg 1−1 casein hydrolysate and 25 g 1−1 sucrose is considered to be a good medium for callus growth and plant regeneration. Embryo‐like structures were observed in the callus of some cultivars but plant regeneration appeared to be predominantly from shoot meristems on the callus surface. The majority of regenerated shoots were green, but chlorophyll deficient shoots were obtained from media containing coconut milk. Green plantlets could be transferred to soil without difficulty.
An Improved Culture Method of Mechanically Isolated Heterokaryons of Potato
Authors: Hein T. , Schieder O.
Published: April 2006

Fused protoplasts between different dihaploid genotype of potato were cultivated in small droplets of liquid medium. It was observed that divisions and sustained development of these protoplasts could only be achieved it they had contact via gas phase to other living cells. The factor being responsible for this effect could not be identified. Nevertheless it was possible under such a culture condition to regenerate somatic hybrid calli from heterokaryons of various fusion combinations of potato.
Substitution Analysis of Plant Regeneration from Callus Culture in Wheat
Authors: Galiba G. , Kovacs G. , Sutka J.
Published: April 2006

The genetic determination of the plant regeneration ability of tissue cultures arising from immature embryos was studied using a ‘Chinese Spring’/‘Cheyenne’ substitution series. Plant regeneration proved to be polygenically determined. In tile current experiment the chromosomes 7B, 7D and ID were found to be effective, although the possibility of other chromosome effects cannot be excluded.
Reinvestigation of the Architecture of the Vascular System within Racemes in Faba Beans
Authors: Ruckenbauer P. , Mollenkope K.
Published: April 2006

A method is described which allows the visual demonstration of the vascular system of the receme of fava beans (Vicia faba L.). 150 recemes of plants of various breeding populations were investigated. It was possible to show the structure of the entire vascular system characteristic of faba bens. The existence of a system of completely independent vascular bundles (IVS), which according to GATES et al. (1983) might avoid the competition between flowers within a receme is though to be improbable.
Morphology, Cytology and Fertility of Avena sativa L. ×A. magna Murph. et Terrell Amphiploids
Authors: Premachandran M. N. , Choubey R. N. , Gupta S. K.
Published: April 2006

The genotypes of Avena sativa were crossed to A. magna Murph. et Terrell, from the sterile pentapliod F1 amphiploids were successfully developed after colchicine treatment. The C1 plants were observed for their morphology, cytology and fertility. These plants were characterized by longer and broader glumes, swollen pedicel attachment, pubescent lemmas, bold seeds and persistent spikelets. Other characters, viz., final plant height, rachis length, peduncle length and spikelets per panicle were intermediate. All plants hail the chromosome number 2n = 70 or close to. 7C. Due to stickiness of chromosomes, meiosis of only two decaploid plants could be studied in detail. The average chromosome Association was 1.3 I + 28.56 II + 1.4 III + 1.77 IV + 0.07 VI and 0.13 I + 28.7 II + 0.14 III + 2.09 IV + 0.59 VI; but in some cells up to 35 bivalents were observed. Seed set as well as pollen fertility and size exhibited great variation.
Tolerance of Triticum Species to Aluminum*
Authors: Berzonsky W. A. , Kimber G.
Published: April 2006

A total of 523 accessions of 25 Triticum species were screened for tolerance of aluminum in solution. Only 22 accessions were identified with some root re growth following exposure w culture solutions containing 12 ppm aluminum. Interestingly, 15 of these 22 accessions were species with the Un genome (T. uniaristatum). The level of aluminum tolerance of none of these 22 accessions is as high as that of the cultivar ‘Atlas 66’.
Modification of Heterosis for Protein and Yield Components by Bean Common Mosaic Virus in Phaseolus vulgaris
Authors: Sarrafi A. , Ecochard R.
Published: April 2006

The effect of bean common mosaic virus on yield, yield components, and seed protein content was studied in tour bean cultivars and their F1 hybrids. The results of this experiment showed 3 significant decrease for yield in diseased plants; the 100 seed weight was also significantly reduced in one of the diseased varieties. The percentage of protein was increased m virus‐diseased plants: this increase was due to non‐protein nitrogen. Usually, the percentage of heterosis in virus‐diseased F1 hybrid of two susceptible varieties was decreased while in F1 hybrids of “susceptible × resistant” varieties it was increased. This study shows the danger of drawing conclusions in quantitative genetic studies then dealing with both diseased and healthy plants.
Simple Genetic Control of Hybrid Plant Development in Interspecific Crosses between Phaseolus vulgaris L. and P. acutifolius A. Gray
Authors: Parker J. P. , Michaels T. E.
Published: April 2006

Crosses were performed between nine Phaseolus vulgaris lines (as females) and seven P. acutifolius lines (as‐ male to examine parental compatibility for the production of vigorous hybrid And backcross plants, in vitro embryo rescue techniques were required to secure hybrid and backcross proseny following interspecific crossing. Seedling development appeared to be dependent on which allele the P. vulgaris parent carried at an interspecific incompatibility locus. Seven of the nine P. vulgaris lines tested carried an allele at this locus which interacted with a nuclear factor in the P. acutifolius genome resulting in stunted, sub‐lethal hybrids. The lines, ICA pijao' and ‘Sacramento Light Red Kidney’ did not carry this allele and produced vigorous hybrid progeny in combination with all P. acutifolius parents. Intensive backcrossing produced progeny which also segregated for sub‐lethal and viable plant development. The observed segregation patterns suggest that a bridge crossing scheme would facilitate the introgression of P. acutifolius germplasm into incompatible P. vulgaris lines. Similarities, with an intraspecific incompatibility system are discussed.
Molybdenum Uptake and Nitrate Reductase Activity in Sorghum (Sorghum bicolor L. Moench). Evidence for Heterosis
Authors: Ramani Saradha , Kannan S.
Published: April 2006

The absorption of Mo by the roots and. transport to the shoot of intact seedlings of a sorghum hybrid and its parent cultivars were measured for 3 h from 10 to 100 μmol ammonium molybdate. The patterns of absorption revealed hybrid vigour and the hybrid followed the patterns of the male‐ parent 168. Studies on the effects of different amounts of Mo on the nitrate reductase activity also showed the occurrence of hybrid vigour in the‐ hybrid CSH‐7.
Cytological and Isozyme Evaluation of Tall Fescue × Italian Ryegrass Hybrids
Authors: Eizenga G. C , Buckner R. C.
Published: April 2006

Development of tall fescue (Festuca arundinacea Schreb., 2n = 6x ‐ 42) × Italian rye‐grass (Lolium multiflorum Lam., 2n = 2 ×= 14) hybrids would enhance efforts to improve the quality of tall fescue. Two ‘Kentucky 31’ tall fescue ×‘Lemtal Italian ryegrass hybrids were obtained via embryo rescue on MS media containing casein hydrolysate, ascorbic acid and sucrose. Chromosome pairing at metaphase I had an average of more than 12 bivalents per cell. Since Festuca‐Lolium pairing can account only for seven of the paired chromosomes, intergenomic as well as interspecific chromosome pairing is indicated. There was no cytoplasmic effect on chromosome pairing.

To determine if enzymes could be used as genetic markers for distinguishing hybrids from self‐contaminants in crosses, zymograms of PGI, 6‐PGD, MDH, GOT and ACPH were obtained from parents and hybrids using starch gel etectrophoresis. PGI, 6‐PGD and MDH had fewer bands in the diploid ryegrass, as compared with the hexaploid tall fescue and the tetraploid hybrid.
Divergent Selection for Heading Date in Barley
Authors: Tuberosa R. , Sanguineti M. C. , Conti S.
Published: April 2006

Divergent selection for heading time was performed in two F2 barley population. Five populations were obtained for each cross: F5 SSD (unselected control), 3E and 3L (from three cycles of selection for earliness or lateness), 2E1L and ZL1E (from two cycles of direct and one of reverse selection). These populations, together with corresponding parents and F2 generations, were evaluated over two years. The response to selection was 5.6 and 6.5 days inane direction (earlier heading) and 7.7 and 6.7 clays in the other direction (later heading) in the two crosses, respectively. 3E and 3L populations were highly transgressive as compared to their parents. A sizeable amount of genetic variability was still present after two cycles of selection. Heading was probably controlled by a polygenic system with prevailing additive effects and alleles for earliness and earliness somewhat equally distributed in the parents. Selection fur heading time led to significant changes in plant height, yield and kernel weight. Early progenies were higher yielding than lace ones.
Triple Test Cross Analysis in F2 Populations of Four Promising Crosses of Field Pea
Authors: Singh B. B. , Singh U. P. , Rai B. , Singh R. M.
Published: April 2006

The components of genetic variation were studied in four F2 crosses (PG3× 5064, T163× B.V., T163× Arkel and 5064 × ED) for quantitative characters such as days to flowering, plant height, pod number, seed number, test weight and yield/plant. The overall epistasis (T type) was, in general, a major contributor for genetically controlling the expression of the characters in all the‐ four crosses except for the character seed number in crosses 1 and JV, where the j + l component at epistasis played a significant role in determining the expression of this attribute:. Though the ‘j + l’ component of the epistasis was significant, it was relatively less important than the ‘i’ type epistasis. Both the additive and dominance components of the genetic variation were highly significant for all the trans studied in all die four sets of crosses. The expression of the dominance was directional only for a few characters in certain crosses. The degree of dominance lies in the partial range, and heritability estimates obtained were high for most of the trails. The possible application of cross prediction in the isolation of superior recombinant inbred lines in pea is discussed.
Use of the Single Seed Descent Method in Breeding Safflower (Carthamus tinctorius L.)
Authors: Fernandez Martinez J. , Dominguez Gimenez J. , Jimenez A. , Hernandez L.
Published: April 2006

The single seed descent (SSD) method of selection has been evaluated in safflower (Carthamus tinctorius L.). The initial population of this study was a BC2F1 from a cross between a well adapted and a high oil cultivar. Transgressive segregation for yield and oil content producing lines with considerably higher values than the better parent was observed in BC2F4 and BC2F5 generations. These results and the great saving of time and effort makes the SSD method a very desirable tool for safflower breeders.
Genetical and Physiological Investigations on Mutants for Polyenoic Fatty Acids in Rapeseed (Brassies napus L.) III. Breeding Behaviour and Performance*
Authors: Brunklaus‐Jung Blisabeth , Röbbellen G.
Published: April 2006

Rapeseed oil is marked by, 1 too low content of linoleic acid and a too high, content of linolenic acid to meet the nutritional quality requirements. First mutants with a considerably improved poly en OIL fatty acid (t.a.) pattern were low in vigour and seed yield. The present experiments were set out to analyze their mode of inheritance and to check the hypothesis chat a low linolenic acid content of the thylakoid membranes inhibits sufficiently high yields of such mutants for physiological reasons.

Six independently induced mutants transmitted the high linoleic and low (or in one cast high linoleic acid content of their seed oil by one recessive gene: two expressed allele mutated allele in an intermediate fashion. Of six double mutants of various origin, three revealed an independent, additive action of two loci for the changed polyenoic f.a. contents, while in the three others the mutant alleles exerted partial dominance over their plus alleles.

One or two backcrosses with productive varieties improved the performance of the mutants stepwise over the original types. It is therefore, concluded that mutations towards the desired polyenoic f.a. convent are not necessarily incompatible with high seed yields, when the responsible genes are transferred into an appropriate genetic background. But strong effects of environment on yield, oil content and polyenoic f.a. content of the mutants were still seen in a yield test of second backcross progenies.
Genetic Analysis of Resistance to Green Leafhopper in Rice
Authors: Tomar J. B. , Tomar Shiksha D.
Published: April 2006

The inheritance of resistance to green leafhopper, Nephotettix impicticeps Ichi, was studied in 11 cultivars of rice, Oryza saliva L. These resistant cultivars were crossed with the susceptible cultivar ‘TN1’. The materials consisted of F1, F2 and F3 populations including parents which were assessed by the bulk screening test. It was found that resistance in the cultivars TR36′, UPR254‐35‐3′‐2′, ‘Jhingasail’, ‘Govind’, ‘RP825‐45‐1‐3’, ‘MRC603‐303’, ‘RD4’, and ‘Irat104’ was conditioned by a single dominant gene, whereas resistance in ‘Ptb8’ IR9805‐97‐1′, and ‘BG367‐7’ was controlled by one recessive gene.

The test on the allelic relationships of the resistance genes in the test cultivars with the known genes Glb1 and Glb2 revealed that the single dominant gene that conveyed the resistance in ‘UPR254‐35‐3‐2’ and ‘Jhingasail’ was allelic to Glh1 and segregated independently of Glh2. The resistance in ‘Govind’ and ‘RP82S‐45‐1‐3’ was governed by the Glh2 gene which was independent of Glh1. The test cultivars ‘IR36’;. ‘MRC603‐303’, ‘RD4’. and Irat104’ had a dominant gene for resistance which was nonallelic to Glb1 and Glb2. The recessive gene which conditioned the resistance in ‘Ptb8’, ‘IR9805‐97‐1’, and ‘BG367‐1’ segregated independently of Glh1 and Glh2.

Eleven trisomics in an ‘TR36’ background were crossed with ‘Java’, a cultivar susceptible to green leafhopper. The segregation pattern of the F2 and backcross generations revealed that the Glb6 gene was located on chromosome 5.
Confirmation of a 1A/1R Wheat‐Rye Chromosome Translocation in the Wheat Variety ‘Amigo’
Authors: Schlegel R. , Kynast R.
Published: April 2006

Differential chromosome staining by using the Giemsa C‐ banding technique and test crosses have revealed rye chroma tin in the hexaploid wheat variety ‘Amigo’ which resulted from wheat crosses with the octoploid triticale ‘Gaucho’. The results demonstrated a pair of translocated wheat chromosomes involving the short arm of rye chromosome 1R and the long arm of the homoeologous wheat chromosome 1A (1Aq/1Rp translocation). The localization of the translocation breakpoint is supposed 10 be within the centromeric region.
Variation, Heritability and Response to Selection in Natural Populations of Caper Spurge (Euphorbia lathyris L.)
Authors: Hondelmann W.
Published: April 2006

Ten natural populations of caper spurge (Euphoria lathyris L.) were evaluated in two greenhouse experiments. It appeared that the ‘between population’ component of variance predominated for most characters. Heritability values Fit into the general picture of seed oil‐containing wild species. From estimates of response to selection it is concluded that for developing caper its genetic‐ base has to be broadened.
Pachytene Chromosomes of Brachiaria ruziziensis Germain et Evrard
Authors: Do Valle C. B. , Singh R. J. , Miller D. A.
Published: April 2006

Brachiaria ruziziensis is a sexual diploid tropical grass species of wide adaptation and good forage quality. Pachytene chromosomes were studied in morphological detail and all nine chromosomes were identified by their length, centromere position, and size and distribution of chromomeres. The idiogram prepared for the first time in this species consists of four median and five submedian chromosomes.
Barley Isolines with Genes for Resistance to Erysiphe graminis f. sp. hordei in the Recurrent Parent ‘Siri’
Authors: Kølster P. , Stølen O.
Published: April 2006

A group of 17 spring barley isolines with genes for race specific resistance to barley powdery mildew were developed by backcrossing using the cultivar ‘Siri’ as the recurrent parent. A test with 22 isolates of powdery mildew showed that each of the 17 isolines had the same reaction as its donor parent, and that 17 different resistance genes or gene combinations are present among the lines‐ The isolines are very similar to ‘Siri’ in morphology and agronomic performance.
Variation in the Carbohydrate Composition of Wild Barley (Hordeum spontaneum) Grain
Authors: Henry R. J. , Brown A. H. D.
Published: April 2006

The carbohydrate content of Hordeum spotaneum lines collected from 23 diverse environments in Israel was investigated. The range in composition was sucrose: 0.83—1.15%; trisaccharides): 0.48—1.16% total free and combined fructose: 1.2—4.2%; pentosans: 4.2—9.9%; and fl→3), (1→4)‐β‐glucans: 4.5—13.2%. The high pentosan and β‐glucan content in some lines would cause quality problems if found in malting barleys.
Plant Regeneration from Protoplasts of Trifolium repens and Lotus corniculatus
Authors: Judith Webb K. , Woodcock S. , Chamberlain D. A.
Published: April 2006

Protoplasts were isolated from leaves of Lotus corniculatus and Trifolium repens and from cotyledons of L. corniculatus. These protoplasts divided and produced colonies. The plating efficiency of protoplasts of both species was improved when agarose was used as a supporting medium. Plants were regenerated more regularly and in larger numbers from colonies of L. carniculatus than T. repens. The use of a culture line of T. repens that had been selected for its response in culture markedly increased the proportion of protoplast‐derived cultures which regenerated shoots. One regenerant of T. repens (P6) was analysed for morphological and cytalogical variation. This plant was abnormal and highly aneuploid with a wide range of chromosome numbers.
The Influence of Dicamba on Somatic Embryogenesis and Frequency of Plant Regeneration from Cultured Immature Embryos of Wheat (Triticum aestivum L.)
Authors: Hunsinger H. , Schauz K.
Published: April 2006

An investigation was made to discover the influence of dicamba on the somatic embryogenesis of winter wheat cultivars‐. Immature embryos of Triticum aestivum cv, ‘Sage’, ‘Caribo’ and ‘Kanzler’ were cultured, on modified N6‐medium with the addition of 1 mg/13,6 dichlor‐2‐methoxy benzoe acid (dicamba).

The young embryos were placed with the embryo axis on to the medium. Under this condition the scutella of the embryos at different stage of development produced compact calli and embryoids which regenerated plants with a high frequency (70 %) four to: six weeks later. The results suggest that dicamba could be of value in the induction of somatic embryogenesis.
Performance of Diploids and Induced Autotetraploids of Catharanthus roseus under Different Levels of Nitrogen and Plant Spacings
Authors: Kulkarni R. N. , Rajagopal K. , Chandrashekar R. S. , Dimri B. P. , Sresh N. , Rajeshwar Rao B. R.
Published: April 2006

Two bulk experimental strains of induced autotetraploids,‘Purple tetraploid bulk’ (PTB) and ‘White tetraploid bulk’ of Catharanthus roseus were evaluated along with the diploid ‘Purple’ variety (PDB) and a diploid pure line selection PS‐3 in four environments consisting of combinations of two levels each of plant spacing and nitrogen at Bangalore and Hyderabad during 1983—84 and in two additional environments at Bangalore during 1984—85. PTB, in general, performed better than PDB at closer plant spacings, especially in the absence of nitrogen application. The highest increase in economic yield (leaf + root yield) over PDB was recorded by PTB with 45 × 30 cm plant spacing and no nitrogen fertilization. The highest economic yield of PTB (obtained with 30 × 30 cm spacing and 100 kg N per ha) was 26 % higher than the highest economic yield of PDB. There were no significant differences between PTB and PDB for content of total alkaloids in leaves within all the environments during both years. Strain × environment interactions were significant for content of total alkaloids in roots during 1983—84. During 1984—85, PTB and PDB did not significantly differ from each other for content of total alkaloids in roots.
Evaluation of Self and Polycross Progeny Testing in Birdsfoot Trefoil (Lotus corniculatus L.) for Forage and Seed Yield
Authors: Onokpise O. U. , Boinley S. R. , Tomes D. T. , Twamley B. E.
Published: April 2006

Self and cross fertility, forage and seed yield of parents, self (Sl), and polycross (PX) progenies were measured in a selected and an unselected population of birdsfoot trefoil (Lotus corniculatus L.), Self fertility was significantly less than cross fertility in both populations. In a field planting S1 progenies had lower forage yield in 1979 and 1980 and seed yield (relative to the parents) was less in the selected population than the unselected in 1979. All correlation coefficients between years and progenies were non‐significant for forage yield bur the parents‐poly cross progeny correlation was significant for seed yield in the selected population. Percentage survival of plants after cutting in 1980 was higher in the selected population, and the parents and PX progenies survived better than S1 progenies in both populations. The better performance of the selected population may be due, in pan, to higher frequency of favorable genes resulting from four cycles of recurrent selection, S1 progeny testing does not appear to be worth while in birdsfoot trefoil because of low self fertility and the reduced vigour of the progeny.
Effects of Competition upon the Productivity of White Clover‐Perennial Ryegrass Mixtures. Analysis of and Interrelations between Characters
Authors: Hill J. , Michaelson‐Yeates T. P. T.
Published: April 2006

A diallel crossing programme amongst tour contrasting white clover varieties was used to generate material for studying the interrelationships amongst those characters which affect the productivity of white clover‐ perennial ryegrass mixtures under a cutting‐only management regime. Such a regime favoured clover growth. All the clover characters exhibited strong positive correlations with mixture yield. However, this combination of clover characters did not promote growth of the grass companion. For this a low growing variety with a dense stolon network appeared preferable. Path analysis indicated that differences existed between the two companion grass varieties used for this experiment in their upon clover characters.
Variation in Relative Amounts of Isolectins in Bread Wheat (Triticum aestivum) Landraces from Northern Nigeria and Chad
Authors: Zeven A. C. , Peumans W. J.
Published: April 2006

Wheat germ agglutin (WGA) present in the embryo of a bread wheat grain is a mixture of three isolectins, viz CLA, CLB and CLD which are coded by genes located on die chromosomes 1A, 1B and 1D. Their respective absolute amounts were determined in 62 Nigerian and five Chad landraces. Added was the Madagascar variety ‘Kanem’ which is stated to be selected from Chad material. Some of the Nigerian landraces were formerly identified as derived from Indian Pakistani wheat varieties/landraces introduced into Northern Nigeria before 1940. These had relatively high CLD/GLA and CLB/CLA ratios. Other Nigerian landraces with such high ratios were postulated to come from India/Pakistan, too.

The Chad wheats, except ‘Kanem’, have WGA amounts and‐ratios similar to those native to Northern Nigeria. This may point to a common history. ‘Kanem’ is said to be bred in Madagascar from Chad wheats. Apparently it has a different origin.

So the determination of the WGA amount and its isolectin composition is a helpful means to identify the history of a land race or of an improved variety.
Testing the Efficiency of Pollination Bag Materials
Authors: McAdam N. J. , Senior J. , Hayward M. D.
Published: April 2006

Crossing bags manufactured from three grades of polyester and three types of paper bags were tested for their permeability to grass pollen. Bags were placed on L. perenne plants of known PGI isozyme genotype. Any pollen passing through the crossing bag and pollinating the plant was detected by assaying its progeny for PGI isozymes. The results obtained allowed differentiation of the various materials for their suitability for pollen proofing.
Comparison of Anther Culture and Hordeum bulbosum Method for the Production of Doubled Haploid in Winter Barley I. Production of Green Plants
Authors: Devaux P.
Published: April 2006

The relative response to two‐major techniques of producing haploids in barley – anther culture and the Hordeum bulbosyum method – were compared using seven F1 hybrids from a winter barley breeding programme. Both techniques were Applied to the same plants with the same number of replications.

358 viable green plants were obtained from 420 spikes ot donor plants used: 147 through anther culture and 211 through the H. bulbosum method.

From the data analysis we found that the response to the two techniques was not significantly different, genotype effect and genotype × technique interaction were highly significant.

The possibility of combining the two techniques in a doubled haploid production programme is discussed.
Effects of Inbreeding and Genetic Variation on Forage Quality Traits and Dry Matter Yield in Dactylis glomerata L. Subspecies
Authors: Santen E. van , Casler M. D.
Published: April 2006

Cultivated 4× clones, 2× germplasm and their respective S; progeny were utilized in this study. Dry matter yield and forage quality data (in vitro dry matter disappearance, cell wall constituents, total nitrogen) were obtained on composited vegetative plant material harvested during four successive 4‐week growth periods in the greenhouse. There was no detectable average inbreeding effect for any of the traits. The group mean of the diploids was significantly lower for in vitro dry matter disappearance than the tetraploid group mean. However, two out of six diploid 51 families exceeded the highest tetraploid family for this trait. The diploids had significantly higher cell wall constituents than tetraploids except for acid detergent lignin. There was more variation for any trait at the diploid level than at the tetraploid level among S1 families as well as within families. Dry matter yield and total nitrogen were significantly correlated in diploids and in tetraploids. However, little variation was detected lot total nitrogen at either ploidy level. The results suggest that selection for improved quality in progeny from interploidy crosses may be more efficient by first selecting at the diploid level followed by scaling to the tetraploid level, rather than selection at the tetraploid level after hybridization.
Isolation of a Spontaneous Chromosome Translocation in Common Wheat
Authors: H Liu B.
Published: April 2006

The genes Ms2 for male sterility and Rht10 for dominant dwarfing located on the short arm of chromosome 4D in common wheat arc closely linked. Male sterile, dwarf F1 plants from the cross of male sterile‘Chinese Spring’× dwarf‘Ai‐bian’were backcrossed with the variety‘Chinese Spring, From this offspring a spontaneous chromosome translocation was isolated resulting in a recombinant male sterile and dwarf genotype.
Genetic Study of Non‐Ear Characters in Maize
Authors: De Ron A. M. , Ordás A.
Published: April 2006

Seventy three populations of maize (Zea mays L.) were grown for two years at two locations in Spain in order to study the heritability and constancy of the non‐ear traits days to silking, days to anthesis, plant height, ear height, and leaf number.

The differences among populations were highly significant in the individual analyses, as well as in the combined analyses for all the traits.

The interaction components of variance were in general small. Broad‐sense heritabilities ranged from 0.844 to 0.869. Constancies were high, in all cases above 1.0.

It is concluded that the non‐ear trails studied can be confidently used in a numerical classification of populations of maize.
Genetic Variation in Enzyme Phenotypes among Yugoslav Wheat Cultivars
Authors: Vapa L. , Hart G. E.
Published: April 2006

The zymogram phenotypes of 14 enzymes were determined for 80 Yugoslav wheat cultivars in order to identify probable allelic variants at structural gene loci. Enzyme phenotypes that differ from the one produced by Triticum aestivum cv.‘Chinese Spring’ were detected for six enzymes, namely, aromatic alcohol dehydrogenase‐1, aconitase‐1, amino peptidase‐l, lipoxygenase‐1, NADH dehydrogenase‐1 and endopeptidase‐1, and one or more probable allelic variants at the Aadb‐B1, Aco‐A1, Aca‐B1, Amp‐Al, Amp‐B1, Ep‐A1, Ep‐B1, Lpx‐A1, Lpx‐B1 or Lpx‐D1, and Ndh‐B1 loci were identified.
Description and Breeding Behavior of Two Partial Male Sterile Guar Plants
Authors: Staford K. E.
Published: April 2006

This investigation describes two partial male sterile plants of guar, Cyamopsis tetragonoloba (L.) Taub. (MS‐1 and MS‐II), and gives results of their hybridization with a fertile cultivar. Detectable natural crossing between MS‐1 plants and a fertile cultivar averaged 20.6%, with maximum crossing of 70 %. Crossing between MS‐II plants and a fertile culuvar averaged 5.0 5.0 % about the same as previously reported for fertile × fertile, crosses. Honeybees, Apis mellifera (L.), caged with MS‐II plants and a fertile cultivar did not increase seed set on male sterile plants. Hand separation of mature pods into short‐ and long‐pod groups was only partially effective in identifying hybrid seed produced on the male sterile plants.
Plant Regeneration from Protoplasts in Linum*
Authors: Ling H. Q. , Binding H.
Published: April 2006

Protoplasts of eight wild Linum species and 14 genotypes of flax, isolated from different parts of seedlings and from shoot apices, were regenerated to callus in medium V‐KM (Binding and Nehls 1977). Plant regeneration was obtained in L. alpinum, L. amurense, L. hologynum, L. perenne, L. salsoloides and eight genotypes of L. usitatissimum on agar media B5 (Gamborg et al. 1968), B5C (Binding et al, 1981), MS (Murashige and Skoog 1962) and MSC (MS with 5% coconut endosperm) containing 2.5μM 6‐BA. An adventitious embryo was regenerated in L. alpinum. Callus differentiation like sponge parenchyma, was observed in protoplast‐derived tissues of L. usitatissimum. Shoots organized roots under slightly divergent conditions in the different species.
Facilitation of Wide‐Crossing Through Embryo Rescue and Pollen Storage in Interspecific Hybridization of Cultivated Allium species
Authors: Gonzalez L. G. , Ford‐Lloyd B. V.
Published: April 2006

Up to 70% success has been achieved using a simple technique of in ovulo embryo rescue for generating progeny From crosses between Allium cepa and A. fistulosum and other wild species of Allium. Pollen storage in liquid nitrogen has overcome problems associated with lack of synchrony of flowering between Allium species. The use of pollen tube growth for predicting crossability is brought into question.