Rye Pollen Research Articles

Determination of vitality of pollen on the basis of its amino acid content

During in vitro germination of corn pollen in media containing exogenous proline pollen tubes grew twice the length as in media without proline. Proline content in vital pollen is very high, in corn 1.5–2.5%, in rye 1.0–1.5% of the dry matter. In many plants vitality and fertility of the pollen is proportional to its proline content. A new staining procedure based on proline content was developed for the indication of vitality of corn ( Zea mays ) and rye ( Secale cereale ) pollen. The staining can be performed on living and on fixed pollen alike.

Standardisierung von Allergenextrakten ? am Beispiel des Roggenpollen

With the exception of ragweed antigen E all attempts to purify pollen allergens have been unsuccessful. Quantitations of allergens are conventionally based on parameters devoid of any relevance to allergenicity in vivo (e. g., Noon — units, w/v etc.). RABS (The Reference Allergen Bioassay Standardization) is carried out in isolated guinea pig mast cells and gives relative allergenicities compared to a standard allergen (Human serum albumin). RABS standardized rye pollen extracts were tested in the course of routine diagnostics in patients: the results of RABS standardization and the results of skin tests were found to agree very well.

Antibody response profiles to components of rye grass pollen extract in various strains of mice.

Using a combination of immunoprecipitation and polyacrylamide gel electrophoresis techniques, patterns of antibody responses to a number of components in rye pollen extract have been studied in hyperimmune mouse sera. Common laboratory strains of mice were investigated, including AKR, C3H/He, SwR, Ist, Asn, Balb/c, C57BL10, DBA2 and BD1:F1 hybrids. All strains responded vigorously to the immunisation protocol used (rye pollen extract/alum followed by a booster dose in aqueous media) when tested with non-discriminating assay procedures such as haemagglutination or passive cutaneous anaphylaxis directed against the whole rye pollen extract. However, markedly variable antibody responses were observed between strains and between murine and human sera when considered in relation to individual rye extract components. Particularly noteworthy was the relatively poor response of all mice to the low molecular weight rye antigen component (11,000 daltons). This material was readily detected by human sera derived from pollenosis patients. Notable also was the fact that no single rye component was detected by all mice sera. These results illustrate the complex serological response induced by heterogeneous antigen mixtures, such as grass pollen extracts.

Histamine release from isolated mast cells as a bioassay system for the standardization of allergens.

Standardization of allergen extracts is still a problems not yet satisfactorily resolved. Allergic sensitization involves not only the production of allergen-specific antibodies of a certain class (IgE) but also changes in the morphological and functional state of the mast cells that bind and carry IgE and react with the allergen. We therefore designed a bioassay which covers the total allergenicity and also antibody-independent allergen effects. It is based on the release of histamine from isolated mast cells of actively sensitized guinea pigs: outbred animals receive one s.c. injection of the allergen extract to be tested and human serum albumin (HSA) as reference (standard) allergen. Three weeks later the mesenteric mast cells of these animals are isolated and challenged in vitro with varying concentrations of the test allergen and HSA. The relationship of the histamine release caused by the reference allergen HSA to that caused by the test allergen (e.g. rye or grass pollen, alternaria, and even house dust) can be used to estimate the sensitizing and challenging potency of the test allergen. For example, 2 different batches of rye pollen gave different results although the values obtained by identical batches were almost identical within 9 months. In addition, irritating impurities of the allergen extract might be recognized.

The site of action of crossability genes (Kr 1, Kr 2) between Triticum and Secale. II. Proportion of pistils containing pollen tubes and effects of alternate pollination on seed set

Different wheat genotypes (T. aestivum) were crossed with rye to ascertain the site or sites of manifestation of the crossability genes, Kr1 and Kr2. By using fluorescence microscopy, it was found that the order of increasing proportion of wheat micropyles containing pollen tubes is strongly correlated with the levels of crossability with rye. High crossable genotypes have more micropyles containing pollen tubes than those of the low crossable ones. Most of the inhibition or retardation of pollen tubes occurred between the style base and top of the embryo sac, expecially with the low crossable genotypes where both Kr-genes are present. The results also indicate that Kr1 is a greater inhibitor than Kr2. Seed set is also highly correlated with the number or proportion of micropyles having pollen tubes. Alternate pollinations seem to support the view that rye pollen tubes do not reach the micropyles of the low crossable genotypes, and hence when repollinated with wheat selfed seeds are produced.

Cross-reactivity between grass and corn pollen antigens.

Analogous reactions of grass and corn pollen extracts in skin tests on patients suffering from pollinosis might suggest an antigenic relationship between grass and corn pollens. This problem was studied using the RAST inhibition test. Tests were performed with cellulose discs labelled with commercial skin test extracts containing grass, rye, wheat, barley, oat and maize pollens. Different mutual inhibitions were measured showing various grades of antigenic relationship. Only grass pollen antigens could strongly inhibit all other antigen-antibody reactions. Thus, we suppose that the investigated grass pollen extract also contains all antigens typical of corn pollen. Therefore, exclusive use of this extract seems to be possible in diagnosis and perhaps therapy of combined grass and corn pollen allergy.

Studies on antigenic relationship between grass- and cult. rye pollens by skin-test, RAST and RAST-inhibition-test in patients with pollinosis (author's transl)

Skin tests on patients suffering from pollinosis suggest frequently an antigenic relationship between various grass and cult. rye pollens. This problem was further studied using both, RAST and RAST inhibition test. The tests were performed with commercial grass pollen discs as well as with self-prepared disc labeled with cult. rye pollens and a combination of various grass antigens. Good agreement was found between self-made and commercial (single antigen) grass pollen discs (95.9%). RAST and skin test correlated also extremely well (92.3%). Mutual inhibition between grass and cult. rye pollens was measured by RAST inhibition test using self-prepared discs. High antigenic relationship between grass and cult. rye pollens was found, however, it could be demonstrated that the antibody pattern varies and contains "grass specific" antibodies.

Jahreszeitliche Veränderungen des Pollengehaltes der Luft

The pollen content of the air in Darmstadt was determined during 6 years (1965 to 1970) using a Hirst spore trap, later a Burkard spore trap. Samples were taken continuously 24 hours a day. The mean changes of the pollen content in defined volumes of air during the years are summarized in two tables, showing the most frequently and rarely found pollen types at the sampling site. Pollen of at least 55 taxa were registered. 70% of all pollen could be associated with 5 taxa, namely with nettle, birch, grasses, pine, and oak. A survey of rye pollen in the air was accomplished to determine the area from which the collected pollen could be originated.

The crossing of common wheat (Triticum aestivum L.) with cultivated rye (Secale cereale L.). I. crossability, pollen grain germination and pollen tube growth

The crossing of common wheat (Triticum aestivum L.) with rye (Secale cereale L.), and especially the action of the crossability genes of wheat, was studied using the readily crossable wheat cv Chinese Spring (genotype kr 1 kr 1 kr 2 kr 2 >), the poorly crossable wheat cv Hope (genotype Kr 1 Kr 1 Kr 2 Kr 2 ), as well as the disomic substitution line of chromosome 5B of Hope into Chinese Spring (CS/Hope 5B, genotype Kr 1 Kr 1 kr 2 kr 2 ). By comparing crossability and actual fertilization, the poor crossability with rye of both cv Hope and the CS/Hope 5B substitution line was shown to result from absence of fertilization. Studies of pollen grain germination and pollen tube growth showed that the dominant alleles of the crossability genes manifested themselves through retardation and eventually inhibition of pollen tube growth at the style base and in the ovary wall. In Hope the growth of all pollen tubes was inhibited, whereas in CS/Hope 5B rarely fertilization was achieved. The recessive alleles of the crossability genes do not seem to have an influence on the growth of rye pollen tubes in wheat pistils.

Pollen production in hexaploid triticale

Comparative studies were made of the pollen characteristics of triticale, wheat, and rye. Measurements were made of the anther length, width, and percent extrusion; pollen viability; size and number of pollen grains per anther; and dispersal on 10-mm2 slide area pollen traps. Triticale anthers were intermediate in length between and significantly different from both wheat and rye. Rye pollen grains per anther were four and two times greater in number than those of wheat and triticale, respectively. Pollen viability was not significantly different between species. Rye pollen grains were smaller than those of wheat and of some triticale cultivars. Simple correlations between anther length and anther width, pollen grains per anther, pollen grain trapped per 10 mm2 slide area, and plant height were significantly positive.

Influence of pollen on germination of conidia of Claviceps purpurea

The in vitro effect of rye, wheat, rape, and tobacco pollen on germination of conidia of Claviceps purpurea was studied at a number of pollen concentrations. Pollen and spore suspensions were incubated together for 24 h before pollen effect was assessed. All pollen stimulated germination of conidia, with rye pollen causing the greatest increase. Wheat pollen had a similar stimulatory effect to rye pollen at comparable concentrations. Rape pollen caused similar stimulation at high concentrations, but less of an effect at low concentrations. Tobacco pollen was less effective than rye pollen at all concentrations. Pollen from host and non-host species was shown to stimulate germination, but the greatest effect was always caused by pollen from the natural host, rye.

THE DURATION OF MEIOSIS IN A DIPLOID RYE, A TETRAPLOID WHEAT AND THE HEXAPLOID TRITICALE DERIVED FROM THEM

Meiosis and pollen development were timed in diploid rye, Secale cereale L. cv. Prolific; tetraploid wheat, Triticum turgidum L. var. durum cv. Stewart; and a hexaploid, Triticale hexaploide cv. 6A190, derived from them. At 20 C the duration of meiosis was about 51 hr in Prolific rye, 31 hr in Stewart wheat, and 37 hr in 6A190 triticale. Pollen development at 20 C lasted about 16 days in Prolific rye, about 9.5 days in Stewart wheat, and about 10 days in 6A190 triticale. These times are in close agreement with estimates previously made for diploid rye, cv. Petkus Spring; tetraploid Triticum dicoccum; and hexaploid triticale cv. RosnerThe high nuclear DNA content of rye pollen mother cells (PMC's) determines a longer meiotic time in both diploid and tetraploid rye than that determined by the lower nuclear DNA contents of PMC's in diploid and tetraploid wheat. The data available may be interpreted to indicate that the relative effect of the wheat and rye genomes in determining the rate of meiotic development in wheat/rye amphiploids varies according to the ratio of wheat to rye genomes. In diploid and tetraploid rye and in 6A190 triticale the proportion of the total meiotic time taken by zygotene and pachytene together (about 40%) differs from the proportion of meiosis which they take in hexaploid wheat and octoploid triticale (about 25%). This difference may be causally correlated with differences between the meiotic stability of rye chromosomes in wheat/rye amphidiploids at the hexaploid and octoploid levels.

The rôle of saprophytic fungi in antagonism against Drechslera sorokiniana ( Helminthosporium sativum) on agar plates and on rye leaves with pollen

About 50 isolates from each of the four dominant groups in the phyllosphere of rye ( Secale cereale) were tested for inhibitory effects against Drechslera sorokiniana ( Helminthosporium sativum) in agar culture. The most antagonistic fungus was Aureobasidium pullulans, followed by the Sporobolomyces spp. group and then the “White yeasts” (mainly Cryptococcus spp.). There was considerable variation in inhibitory activity within each group on agar. Isolates of Cladosporium spp. did not show any antagonistic effect against Drechslera in vitro. Inoculations of living rye leaves with D. sorokiniana and isolates from each group of saprophytic fungi always resulted in a remarkable reduction of infection in the presence of rye pollen, contrasting with the varying degrees of antagonistic effect observed in agar culture. Development of superficial mycelium of the pathogen on the rye leaf surface and the subsequent severity of necrosis are positively correlated. Both on leaves and on slides coated with agar, it was the enhanced superficial mycelial growth of the pathogen in the presence of pollen which was inhibited by the saprophytes. Germination of the Drechslera spores was not affected.

Attempts to define and mimic the effects of pollen on the development of lesions caused by Phoma betae inoculated onto sugarbeet leaves

SUMMARYExpanding lesions resulted when conidia of Phoma betae Frank, mixed with rye pollen, were inoculated on to sugarbeet leaves by a standard technique. Conidia without pollen generally caused non‐expanding necrotic spots; these could be made to spread later by covering them with pollen or orange juice, but not with water.Germ‐tube growth was quicker on water agar than on sugarbeet leaves. Pollen extract stimulated germ‐tube growth on leaves 10 h after inoculation and resulted in the production of knots of hyphae overlying areas where intercellular hyphae could be discerned and where expanding lesions developed.Some inorganic salts mimicked the stimulatory effect of pollen on germtube growth on agar slides, but only a mixture of hexose sugars with boric acid reproduced the effect of pollen on both numbers and size of expanding lesions caused by P. betae on sugarbeet leaves, and numbers of expanding lesions caused by Botrytis cinerea Pers. ex Fr. on bean leaves.

Allergens from common rye grass pollen ( Lolium perenne)—II : The allergenic determinants and carbohydrate moiety

The chemical structures of the carbohydrate moieties of both prominent group I rye pollen allergens appeared to be identical; however, it seems unlikely that these moieties are essential for allergenic activity. From investigations of both chemically-modified and enzymically-digested allergen molecules, it is concluded that an intact, or partially intact, tertiary structure is required for full allergenic activity. The demonstration that the group I allergens dissociated into smaller fragments under suitable conditions (e.g. in solutions containing sodium dodecyl sulphate) suggests a possible mechanism whereby these molecules permeate the mucous membranes, causing allergic response in susceptible individuals.

Allergens from common rye grass pollen ( Lolium perenne)—I : Chemical composition and structure

The amino-acid compositions of two prominent rye pollen allergens of the so-called ‘major group’ (I-B and I-C), showed many striking similarities. Molecular weights of 27,000 and 26,700, respectively, were calculated from these analyses. Both tryptic and chymotryptic ‘fingerprints’ of allergen I-B were very similar to the corresponding fingerprints of I-C, but showed marked differences from those of a further allergenic fraction, II-B, of rye allergenic group II. Peptides containing specific amino acids, including cystine, were also located on the fingerprints of the group I allergens. The above results provided further substantiation for the classification of rye grass pollen allergens into the groups of isoallergens suggested by previous physical and immunological data.

'Isoallergens' from rye grass pollen.

SEVERAL methods for the purification of allergens from pollens and from other vegetable and animal sources have been reported1–9, but recently, by utilizing highly selective chromatographic procedures, it has been possible to obtain allergens of much higher purity than hitherto described10,11. At least two groups of allergens have been found in rye pollen, a major group, active in the majority of sensitive patients, and a minor group, active in only a small proportion. It seems likely that such groups also exist in other grass and ragweed pollens causing hay-fever.

A gene mutation in wheat concerning the crossability with rye.

1) In the crossmg expenment performed with rye vanety "Petkuser" (Secale cereale L ) more than 50 plants of a wheat vanety "Nisimura" ( Triticum aestivum L.) showed a ihigh crossability, but one plant failed to set any seed in 1948. . I.n the following generation the latter when selfed gave seven plants showrng low crossability (0.0-8%) The low crossability continued in the progeny, except one mutation plant given rise to in 1958 (Tab. 1). This strain was named "Nisimura-kawari" which means a mutant from "Nisimura ". 2) From a further crossing experiment it was clearly established that crossability of "Nisimura" with rye pollen was 56. 6-74. 6%, while that of "Nisimura-kawari" 1. 1-4.1 %only. 3) Gene analysis of crossability was made in F1 and F2 hybrids of "Nisimura x Nisimurakawari" and its reciprocal cross. The low crossability "C" of "Nisimura-kawari': was found to be completely dbminant over the high crossability "c" of original " Nisimura ". The genotype of " Nisimura " is cc, and that of "N1srmura kawan " CC. " Nisimurakawari" seems probably to have arisen from "Nisimura" by mutation of one gene .c->C.

Grass pollen extracts. IV. The biological activity of rye pollen extracts and their fractions.

Grass pollen extracts. IV. The biological activity of rye pollen extracts and their fractions.

Grass pollen extracts. III. Some chemical and physical properties of fractions from rye pollen extracts.

Grass pollen extracts. III. Some chemical and physical properties of fractions from rye pollen extracts.