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Maize (Zea mays L.) grain endosperm is triploid (3n), of which 2n come from the male (transferred by pollen) and only 1n from the female plant, thus a major impact of the male form can be expected on grain quality parameters. A good example of this relationship is the phenomenon of xenia. The aim of this study was to determine the effect of pollen on grain quality. The field experiment was conducted in 2011; seeds were harvested from eight cultivars: Bosman, Blask, Tur, Kozak, Bielik, Smok, SMH 220 and Kresowiak, derived from free pollination and controlled self-pollination of maize. Analyses of nutrient contents and starch content in the grain were conducted in the laboratory. In addition, 1000 grain weight and the hectoliter weight of all grain samples were recorded. The results confirmed differences in grain quality of maize hybrids obtained by self-pollination and by open pollination. Grain of maize plants obtained by open-pollination was characterised by higher contents of N-free extract and starch, and lower protein content. Undertaking further studies on this subject may indicate specific recommendations for agricultural practice, such as mixtures of hybrids with good combining abilities, which will contribute to improved grain quality without additional costs.

A new xenicane-type diterpenoid, xeniaoxolane, containing tetrahydrofuran, was isolated from the Okinawan soft coral of the genus, Xenia along with xeniolide-A and xenialactol. The relative configuration of xeniaoxolane was determined based on spectroscopic analysis. The absolute configuration of xeniolide-A was determined using the modified Mosher's method and those of xeniaoxolane and xenialactol, by chemical conversions.

Carl Correns (1864-1933) came to recognize Mendel’s rules between 1894 and 1900 while trying to find out the mechanism of xenia, that is, the direct influcence of the fertilizing pollen on the mother plant in maize and peas among other species. In this paper, I am concerned with the ten years of Correns’ work after the annus mirabilis of 1900 until 1910, when the main outlines of the new science of genetics had been established. It is generally assumed that after 1900 Correns quickly began probing the limits of Mendelian inheritance, both as far as the explanatory force of formal transmission genetics and the generality of Mendel’s laws are concerned. A careful examination of his papers however shows that he was much more interested in the scope of Mendelian inheritance than in its limits. Even his work with variegated Mirabilis plants, which historiographical folklore still presents as a result of Correns’ growing interest in cytoplasmic inheritance, can be shown to have been conducted to corroborate just the opposite, namley, the validity of the nuclear paradigm. The paper will show that Correns’research results in those years (among them the Mendelian inheritance of sex in higher plants) were the outcome of a complex experimental program which involved breeding experiments with dozens of different species.

Six new xenicane diterpenes have been isolated from the acetone extract of the soft coral Xenia florida. Two of them are diterpenes containing a bicyclic [4.3.1] ring system. Three of them seem to be precursors for diterpenes possessing the bicyclic [4.3.1] ring system. One is a common monocarbocyclic diterpene with a cyclononane skeleton.

Seven new xenia diterpenes have been isolated from the soft coral, Xenia florida. Four of them possess a bicyclic [4.3.1] ring system. The three others, which contained a cyclononane skeleton with an epoxide, seem to be precursors for diterpenes with a bicyclic [4.3. 1] ring system.

The agronomic profitability of nut production in pistachio (Pistacia vera L.) is hampered by several factors such as the production of empty nuts, the small size and dry weight of the edible kernel and the low percentage of endocarp dehiscence. The causes underlining these problems are still unknown. The effect of pollinations with pollen from P. atlantica and six different P. vera genotypes on several fruit, nut and embryo characters was compared to study possible xenic and/or metaxenic effects. The use of P. atlantica pollen affected some traits, but there were no clear differences when the pollen of the different P. vera genotypes was used suggesting that, at the intraspecific level, the main limitation to pistachio fruit production problems might not be due to pollen factors.

An improved method for the isolation of leaf mesophyll protoplasts ofSolanum tuberosum L. cvs. Xenia and Bintje, their culture and regeneration to plants is described. The improvements involve the culture of nodal stem explants on Schenk and Hildebrandt (SH) medium supplemented with AgNO3 (7.5 mg 11) and Alar 85 (5 mg 1−1), and the pre-treatment of donor plants for 2–3 weeks at a short photoperiod (6 h), a low irradiance (17 (μmol m−2s−1) and a low temperature (20 °C). Regeneration of cell wals was observed within 2–3 d and cell divisions within 7–12 d after resuspending freshly isolated protoplasts in Sidorov et al. (SW) medium. The resulting microcalli were cultured on solid media containing zeatin (1–2,5 mg 1−1) and/or NAA (0.1 and/or 0.01 mg 1−1) and subsequently on medium with BAR (0.25 mg1−1) and GA−3 (0.1 mg 11) for shoot regeneration.

Although xenia is widespread in plants and has applications in genetics, physiology, breeding and production, its mechanism remains poorly understood. Here I briefly discuss several previous explanations for xenia, and propose an mRNA action hypothesis, which is consistent with Darwin's Pangenesis.

Gerbera (Gerbera jamesonii, Hook.), named in honour of Traug Gerber, is commonly known as Transvaal Daisy, or Barberton Daisy. It is a dwarf perennial herbaceous plant growing in clumps with solitary flower heads on long slender stems which grow well above the foliage. The flowers come in a wide range of colours including yellow, white, orange, pink, crimson and purple. Gerberas are good for beds, borders, rock gardens, pot culture and cut flowers. The flowers suit very well in different floral arrangements. Gerberas can be successfully grown both on plains and in the hills. In western countries they are usually grown in greenhouses, but in mild weather are even grown outdoors on the south-west side. Cultivars of commercial importance are Maroon, the Clementine series, Xenia, Flamengo, Delphi, Apple Blossom and Uranus [1].

With the aim of promoting radiological research, the Xenia Forsselliana Fund was established in 1941 on Gosta Forssell's 65th birthday. In 1942, it was decided that a Xenia Forsselliana Prize shoul...

Two new xenia diterpenoids, xeniatine A (1) and xeniaether A (2), the latter containing a tetrahydrofuran, have been isolated from a soft coral, Xenia sp.

Floridicin 1, a diterpene containing a [4.3.1] bicyclic ring system, has been isolated from the soft coral Xenia florida, and represents a new class of tricarbocyclic diterpenes.

Xenia and metaxenia are phenomena dealing with the effects that pollen from different sources have on certain characteristics exhibited by seeds and fruits in a variety of species. A review of dictionaries, textbooks, and the scientific literature reveals that there is widespread confusion with regard to the nature of these phenomena and how they are to be distinguished. This discussion will attempt to clarify the boundary between these related phenomena by examining both the origins of the terms and our present understanding of the metabolism and anatomy involved. From this perspective, we contend that xenia applies to pollen effects as exhibited in the syngamous parts of ovules, that is, the embryo and endosperm only. Metaxenia applies to such effects found in any structure beyond the embryo and endosperm, this is, in tissues which derive wholly from mother plant material. Metaxenia then encompasses effects found in seed parts such as the nucellus and testa as well as those found in carpels and accessory tissue.

Investigation of the terpenoid content of three soft corals from the Gulf of Eilat (The Red Sea), Xenia macrospiculata, X. obscuronata and X. lilielae resulted in the isolation of 8 new diterpenes Two of the new compounds belong to the xeniolides (xenialactol-D ( lOa ) and xeniolide-E ( 1 )) and the other six (4,14-diepoxyxeniaphyllene ( 15 ), 4,5 - epoxyxeniaphyllan - 14,15 - diol ( 17 ), 4,14 - diepoxy - xeniaphyllenol - A ( 21a ), xeniaphyllenol-B ( 23a ), xeniaphyllenol-C ( 24a ) and xeniaphyllantriol ( 25 )) are new xeniaphyllanes (prenylated caryophyllanes). The structure determination of the various compounds is based on chemical transformations as well as on the 1 H and 13 C NMR spectra. Several known caryophyllene derivatives have been synthesised for 13 C NMR spectra and chemical comparisons. The 13 C NMR has proven to be an excellent probe for structural and stereochemical determinations.

1. Contractions of the polyps of the soft coral Xenia elongata were studied by suspending the polyps in an organ bath and recording changes in tension. 2. Spontaneous contractions included regular oscillations in tension occurring at a frequency of approximately 1/min due to contractions of the column of the polyp. Contractions of the tentacles were superimposed on the column contractions and occurred with frequencies of 10–20/min. 3. The methyl ester of 15-epi-acetoxy PGA; and the diterpenes-(−)sarcophytoxide and thunbergol, isolated from soft coral eggs, stimulated contractions of the polyps. 4. Acetylcholine, methacholine, histamine, dimethylsulfoxide and the diterpene pukalide did not have any effects on the isolated polyps. 5. It is concluded that the egg-specific PGA2 and some diterpenes caused contractions of soft coral polyps and could be involved in the expulsion of eggs during spawning.

Eleven Na-azide induced barley shrunken endosperm mutants expressing xenia (sex) were characterized genetically and histologically. All mutants have reduced kernel size with kernel weights ranging from 11 to 57% of the wild type. With one exception, the mutant phenotypes are ascribable to single recessive mutant alleles, giving rise to a ratio of 3∶1 of normal and shrunken kernels on heterozygous plants. One mutant (B10), also monofactorially inherited, shows a gene dosage dependent pattern of expression in the endosperm. Among the 8 mutants tested for allelism, no allelic mutant genes were discovered. By means of translocation mapping, the mutant gene of B10 was localized to the short arm of chromosome 7, and that of B9 to the short arm of chromosome 1. Based on microscopy studies, the mutant kernel phenotypes fall into three classes, viz. mutants with both endosperm and embryo affected and with a non-viable embryo, mutants with both endosperm and embryo affected and with a viable embryo giving rise to plants with a clearly mutant phenotype, and finally mutants with only the endosperm affected and with a normal embryo giving rise to plants with normal phenotype. The mutant collection covers mutations in genes participating in all of the developmental phases of the endosperm, i.e. the passage from syncytial to the cellular endosperm, total lack of aleurone cell formation and disturbance in the pattern of aleurone cell formation. In the starchy endosperm, varying degrees of cell differentiation occur, ranging from slight deviations from wild type to complete loss of starchy endosperm traits. In the embryo, blocks in the major developmental phases are represented in the mutant collection, including arrest at the proembryo stage, continued cell divisions but no differentiation, and embryos deviating only slightly from the wild type.

Recruitment of soft corals (Octocorallia: Alcyonacea) on concrete plates was studied in the reefs of the Nature Reserve of Eilat at depths of 17 to 29 m over 12 yr. Xenia macrospiculata was the pioneering species, appealing on the vast majority of the plates before any other spat. This species remained the most conspicuous inhabitant of the substrata throughout the whole study. Approximately 10 % of the plates were very extensively colonized by X. rnacrospiculata, resembling the percentage of living coverage by the species in the surrounding reef, thus suggesting that during the study X. rnacrospiculata populations reached their maximal potential to capture the newly available substrata. The successive appearance of an additional 11 soft coral species was recorded. The species composition of the recruits and their abundance corresponded with the soft coral community in the natural reef, indicahng that the estabhshed spat were progeny of the local populations. Soft coral recruits utilized the edges and lower surfaces of the plates most successfully, rather than the exposed upper surfaces. Such preferential settling of alcyonaceans allows the spat to escape from unfavourable conditions and maintains their high survival in the established community.

In progeny lines selected from bulk hybrid populations which had been grown the genera-tion accelerating conditions in greenhouse, the degree of fixation for some agronomic chara-cters was often lower than that expected from the degree of generation advance. In order to clarify the causes of this phenomenon the amount of outcrossing was inves-tigated by observing xenia grains on glutinous rice varieties grown in mixtures which non-glutinous varieties under different planting patterns in a greenhouse in 1974 and 1978 (Table 1). The percentage of xenia grains varied between O and 92. 9 per 'cent, depending on crop-ping season and planting density (Table 3 and 4). High percentage of xenia grains was observed under high planting density. This may presumably a result of pollen abnormity under unusual conditions such as low temperature or close spacing in the greenhouse. As expected, the xenia grains increesed when a glutinous variety was interplanted in close proximity to a non-glutinous variety and percentage of ripened grains of the glutinous variety was low (Table 4, Fig. 1). These results were consistent with the reports that the amount of outcrossing was promoted by the cool weather and close distance in the field. It can be presumed that of genetic segregation of several agronomic characters observed after rapid generation advance was patially caused by outcrossing between plants in the gteenhouse.

Der neue Naturstoff (I) fand sich erstaunlicherweise nur in Bestanden, die vor Heron Island (Australien) gesammelt wurden, nicht dagegen inExemplaren von der Picnic Bay, Magnetic Island (Australien) oder von den Fidschiinseln.

The settling behaviour and substratum preferences of the planulae of the Red Sea soft corals Xenia macrospiculata Gohar and Parerythropodium fulvum fulvum (Forskl) were examined in the laboratory. The planulae of the two species have a short pelagic phase and they tend to settle immediately upon leaving the parent colonies. Mucous secretion is used by the larvae for crawling and adhering to the substratum. They exhibit an aggregated pattern of settlement. The developing polyps are found in depressions or pits of the substratum. The planulae preferentially settle on rough substrata and avoid smooth surfaces. They search for substrata covered with an organic coating, composed of turf or crustose coralline algae. Such substrata create better conditions for larval settlement and metamorphosis. The planulae of P. f. fulvum exhibit a striking preference for upside-down attachment on undersides of the substrata, while Xenia macrospiculata utilizes both substratum faces for settlement. Light intensity seems insignificant in determining attachment sites. The findings of the experiments correspond well with the distributional patterns of juveniles of the two species as found in the natural environment. The specific requirements for settling of both species increase their chances of successful development and thus enhance their survival.

Genotypic frequency data at two loci governing blue vs. white aleurone color in barley showed that composite cross (CC) populations grown at Davis varied in the changes in allelic frequencies as well as heterozygosity levels. The blue class increased steadily over 20 generations in CC V and CC XXI along with an excess of heterozygotes over expected under high selfing rates, fluctuated without a directional shift in CC XIV, and declined in CC XVI. Utilizing the xenia feature of this character, nearly 100 Bl/bl Bl2/bl2 individuals were randomly drawn from the CC XVI and CC XXI populations and used in a paired-plot study of some yield components for comparing the blue and white isogenic classes within lines in the varied genetic backgrounds of different lines. For seed number blue vs. white isogenic class differences were significant only in one out of four populations (CC XXI-F8) whereas differences among the lines were significant in CC XVI-F12, CC XXI-F3 and CC XXI-F8. Thus, specific locus effects were relatively much smaller than the genetic background component although overall the genotypic frequency changes at the aleurone color loci were found to be consistent with the relative average seed output per plant in the three genotypic classes.

The devastating tornado of April 3, 1974, provided Xenia, Ohio, with an opportunity to rebuild while avoiding past mistakes in planning and zoning. A comprehensive redevelopment plan stressing downtown revitalization, housing reconstruction, and floodplain zoning, was approved. Simultaneous approval of “overlay zoning,” however, permitted the reemergence of pretornado forces to affect redevelopment of the impacted area. Three years after the tornado, elements of the “old Xenia” are appearing in renewed strip development and continued downtown decline, a reaffirmation of residential discard in “undesirable” areas, and continued uncoordinated environmental development. This article focuses on the persistence of these predisaster motivations and their probable effect on Xenia's future.

The expulsion of zooxanthellae by octocorals (Xenia macrospiculata and Heteroxenia fuscescens), the scleractinian coral Stylophora pistillata, and the hydrocoral Millepora dichotoma, was measured in the field. The numbers expelled did not exceed 0.1% of the total standing stock of symbiotic algae per day, the rate of expulsion was less than 4% of the rate at which cells are added to symbiotic populations, and the carbon lost represented 0.01% of the total carbon fixed on a daily basis. Expulsion of zooxanthellae is therefore not a significant sink for fixed carbon in these symbiotic associations. In contrast to field populations, expulsion by X. macrospiculata increased 5-fold or more in the laboratory, suggesting that laboratory conditions may introduce stress.

A b s t r a c t : The inheritance of four endosperm variants of sorghum that exhibit xenia effects was studied in the F-|, F2, and backcross seed of crosses among variants and with the normal type. It was concluded that the endosperm variants vani, sugary {su), and high lysine (hf) are controlled by three independent single recessive alleles and that dimpled endo­ sperm is controlled by a single recessive allele (dp) allelic to that controlling the vani endosperm trait. S e v e r a l natural endosperm variants exhib­ iting shrivelled or deformed grains are known in sorghum {Sorghum bicolor L. M oench). Dimpled seed exhibit a depression on the grain and are controlled by a single recessive allele designated as d p 1. Sugary grains are characterized by a hard and crystalline endo­ sperm and large depressions or pitting near the stylar as well as hilar ends, thus giving the grain a wrinkled appearance. Karper and Quinby4 found that sugary grains were con­ trolled by a single recessive allele (su ). Vani sorghums, popularly used in the M aharash­ tra state o f India to make a sweet snack called hurda, are characterized .by grains with a soft endosperm exhibiting a dimple on the side opposite to the hilum. Karper and Quinby4 discussed the inheritance of vani grains reported from India and concluded that the alleles governing vani and sugary grains were synonymous. Schertz and Ste­ phens7 recommended the gene symbol su for the characters sugary and dimpled. It was found that the endosperm variants sugary, dent, and defective were controlled inde­ pendently by single recessive alleles3. Murty et al.5 reported the inheritance o f dimpled grains exhibiting the basmati (scented) char­ acter in the sorghum cultivar, K EP-472 (IS 19907), and found that dimpled and scented characters were controlled by two independ­ ent recessive alleles. During the course of these investigations the authors observed that crosses of the dimpled basmati (hereaf­ ter called dimpled) with vani and sugary variants resulted in contrasting behavior. We therefore undertook a detailed study o f the interrelationships among, the alleles control­ ling the sugary, vani, and dimpled endosperm variants. Another important endosperm vari­ ant exhibiting shrivelled seed, namely, high lysine (h l ) % also was included in these stud­ ies. This paper presents the results obtained from intercrosses of these four endosperm variants with a normal parent and among themselves.

The anatomy of seven species of aeolid opisthobranch molluscs is described. They are all considered to be specialized feeders on alcyonarian coelenterates and to belong to one genus Phyllodesmium (Glaucidae; Favorininae). Two species are considered to be new. Favorinus horridus Macnae, Aeolidia poindimiei Risbec, Cratena macphersonae Burn and another species not studied in this paper, Hervia serrata Baba, are transferred to Phyllodesmium from the genera in which they are currently placed. Myrrhine Bergh, Babaiella Risso-Dominguez and Phyllodesmiopsis Risso-Dominguez are considered synonyms of Phyllodesmium. The two new species feed on Xenia and P. poindimiei feeds on Telesto. It is shown that the species of Phyllodesmium exhibit an evolutionary series in the development of symbiosis with zooxanthellae. The zooxanthellae are obtained from the alcyonarians upon which the aeolids feed. Morphological peculiarities present in some members of the genus are considered to be associated with the symbiosis.