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Oenothera laciniata Hill (Onagraceae) collected from Ajmer district is reported here as an addition to the Flora of Rajasthan State. A detailed description and color photograph as well as herbarium specimen are provided to facilitate identification.

Weed monitoring and survey was conducted to detect appearance of new weed species. Ten new weed species namely Galium spurium Linn. (family Rubiaceae), Geranium nepalense Sweet (family Geraniaceae), Lamium amplexicaule Linn. (family Lamiaceae), Evolvulus nummularius (family Convolvulaceae), Euphorbia thymifolia Linn.(family Euphorbiaceae), Oenothera laciniata Hill (family Onagraceae), Soliva anthemifolia (Juss.) R. Brown (family Asteraceae), Verbesina encelioides (Cav.) Benth. and Hook. f. ex A. Gray (family Asteraceae), Nicotiana plumbaginifolia Viv. (family Solanaceae) and Portulaca oleracea L. (family Portulacaceae) have been recorded in the last decade from different places of Punjab State. Out of these, weed species namely, O. laciniata, L. amplexicaule, S. anthemifolia and G. nepalense were mainly observed inhabiting the crop fields. Three weed species namely, G. spurium, N. plumbaginifolia and V. encelioides were observed growing along roadsides, wastelands, canal banks and uncultivated areas. P. oleracea and E. thymifolia were observed growing on bunds of agricultural fields. E. nummularius is a serious weed of lawns and landscapes. These weeds have now domesticated in the studied ecological niche and may potentially harm the biodiversity of those areas.

Laboratory and greenhouse studies were conducted to determine the effect of temperature, solution pH, water stress, and planting depth on cutleaf eveningprimrose germination and emergence. Field studies were conducted to measure growth parameters of cutleaf eveningprimrose throughout the fall season. When treated with constant temperature, cutleaf eveningprimrose germinated over a range of 15 to 32 C, with the optimum germination occurring at 24 C. Onset, rate, and total germination were greatest in an alternating 20/35 C temperature regime. Germination decreased as solution pH increased, with greatest germination occurring at solution pH of 4. Germination decreased when cutleaf eveningprimrose seed was subjected to increased water stress. Emergence was optimum when seed were buried at depths of 0.5 cm. Germination decreased with increasing burial depth, and no seed emerged from a depth of 10 cm. Cutleaf eveningprimrose control was maximized when 2,4-D was applied in mixture with glyphosate or pa...

We conducted field and culture experiments to study the effects of arbuscular mycorrhizal (AM) fungi on the establishment of the alien plant Oenothera laciniata (Onagraceae) in a coastal sand dune in Japan. We examined the distribution of plants, AM fungal colonization of their roots, and fungal spore density in the soil of a coastal sand dune at Keinomatsubara, Hyogo Prefecture, western Japan. Of the nine dominant plant species at the study site, six species, including O. laciniata, were heavily colonized by AM fungi. The spore density tended to decrease from inland toward the shoreline, but there were no significant relationships between the level of AM fungal colonization and spore density. Seedlings of O. laciniata inoculated with AM fungi, as well as uninoculated seedlings, were transplanted to the study site. No significant difference in survival rates was detected between the two groups of seedlings. We also examined the effects of AM infection and nutrient (N and P) application on plant g...

Three new dimeric hydrolysable tannins, oenotheins D, F and G, together with known tannins including the macrocyclic oligomers, oenotheins A and B, have been isolated from roots and stems of Oenothera laciniata. Their structures were elucidated on the basis of chemical and spectral evidence. Oenotheins D and F were macrocyclic dimers isomeric with oenothein B in relation to the orientation of the valoneoyl groups linking the monomers.

The objectives of this study were (i) to test the hypothesis that changes in phenology with CO2 are a function of the effect of CO2 upon growth and (ii) to determine if CO2-induced changes in phenology can influence competitive outcome. We examined the effect of 350, 525, and 700 μL∙L−1 CO2 on Guara brachycarpa, Gailardia pulchella, Oenothera laciniata, and Lupinus texensis. Plants were grown as individuals in 150-, 500-, or 1000-mL pots and in competition in 1000-mL pots. Growth and development were monitored at twice-weekly intervals by recording the number of leaves and noting the presence or absence of stem elongation, branching, flower buds, and open flowers. Elevated CO2 affected both growth and phenology, but the direction and magnitude of effects varied with species and soil volume. Elevated CO2 did not appear to affect development through its effect on growth. Those treatments in which there were significant effects of CO2 on growth were generally different from those treatments in which CO2 affected phenology. Rather than affecting phenology by changing plant size, CO2 appeared to affect phenology by modifying the size at which plants switched from one stage to the next. The level of CO2 changed competitive outcome; the importance of Lupinus increased whereas that of Oenothera decreased with increased CO2. These changes were more closely related to the effect of CO2 on growth than its effect on phenology. Key words: time of flowering, size at flowering, competition, photoperiod, rate of development.

The major phytotoxin produced by Pestalotiopsis oenotherae, a pathogen of evening primrose, has been identified as oxysporone, a compound not previously known as a phytotoxin. Pestalopyrone, a minor new toxin, has been shown to be 6-(1′-methylprop-1′-enyl)-4-methoxy-2-pyrone. The gibberellin synergists pestalotin and hydroxypestalotin, also produced by this fungus, are only weakly phytotoxic.

Growth of `Apache' pecan [Carya illinoinensis (Wangenh.) K. Koch] seedlings was evaluated for 3 years when grown in a 11.2-m2 weed-free area or when various combinations of one or two plants of cutleaf evening primrose (Oenothera laciniata Hill), a cool-season species, or Palmer amaranth (Amaranthus palmeri S. Wats.), a warm-season species, were grown 30 cm from the tree, with the rest of the 11.2-m2 area weed-free. Either weed species alone suppressed tree growth compared to the weed-free control. A temporal succession of primrose followed by amaranth reduced growth most. After 3 years, two plants of primrose followed in succession by two of amaranth caused a 79% reduction in cumulative current-season's growth.

Oenothera sinuata Linnaeus, Mantissa Plantarum Altera: 228. 1771. "Habitat in Virginia." RCN: 2659. Type not designated. Original material: Herb. Linn. No. 484.6 (LINN); [icon] in Plukenet, Phytographia: t. 203, f. 3. 1692; Almag. Bot.: 235. 1696. Current name: Oenothera laciniata Hill (Onagraceae)., Published as part of Jarvis, Charlie, 2007, Chapter 7: Linnaean Plant Names and their Types (part O), pp. 696-717 in Order out of Chaos. Linnaean Plant Types and their Types, London :Linnaean Society of London in association with the Natural History Museum on page 698, DOI: 10.5281/zenodo.291971

Oenotherin T(1) was isolated from leaves of Oenothera tetraptera as a major ellagitannin. Its structure, that of a macrocyclic trimer with a new acyl group, an isodehydrovaloneoyl group, was established. This compound was also produced by callus tissues induced from O. laciniata leaves.

Electrophoretic studies have revealed remarkable variability within and among populations of several unisexual animal species. Multiple genotypes, detected by various allozyme phenotypes, exist for unisexual insects (Parker et al., 1977; Suomalinen et al., 1977; Mitter et al., 1979), fishes (Schultz, 1977), lizards (Uzzell and Darevsky, 1975; Parker and Selander, 1976) and annelids (Christensen et al., 1976; Jaenike and Selander, 1979). The few studies employing allozymes as genetic markers for clonal plant species have either focused closely on one or a few populations (Solbrig and Simpson, 1974; Hancock and Wilson, 1976; Hancock, 1977; Steiner and Levin, 1977; Silander, 1979) or concentrated mainly on interpopulational differences (Solbrig, 1971; Levin, 1975; Levy and Winternheimer, 1977; Ellstrand and Levin, 1980a, 1980b). No study has yet described genotypic diversity both within plant populations and over the range of a clonal plant species. The object of this study is to obtain a minimal determination of levels of diversity in a clonal plant species and compare these levels with those exhibited within and among populations of unisexual animal species. The species chosen for study is Oenothera laciniata Hill, an annualwhich occurs in disturbed sandy soils from Texas east to the Atlantic coast and north to Illinois and New Jersey (P. Raven, pers. comm.). This species is a permanent translocation heterozygote, cytogenetically studied throughout its range (Hecht, 1950; Gregory and Klein, 1960; McMullen, 1966; Cleland, 1968; P. Raven and W. Dietrich, pers. comm.). Permanent translocation heterozygosity is an unusual genetic system which results in an effectively asexual mode of reproduction (for details, see Cleland, 1972). Oenothera laciniata is probably a derivative of 0. grandis Smyth, an outcrosser with a conventional genetic system, which occurs primarily in south and central Texas (Munz, 1965; Ellstrand and Levin, 1980b).

The hypothesis that outcrossers are competitively superior to close relatives with specialized genetic systems was tested. Interspecific competition between three closely related Oenothera species was examined in common garden environments. Oenothera grandis, an obligate outcrosser, is competitively superior to its derivative, 0. laciniata, an obligate chromosomal heterozygote. Both of these species are superior to 0. mexicana, a closely related facultative selfer. These relationships were consistent over two levels of density stress. Therefore, in this species triad, the outcrosser has a competitive advantage over its close relatives with derived breeding systems.

SYNCHYTRIUM FULGENS was first described by Schroeter (1873) as a parasite of Oenothera biennis in Germany, and since that time it has been reported from Switzerland, Ecuador, Japan and the United States of America on the same host and on other species of Oenothera as well as Epilobium and Clarkia. From specimens present in herbaria in the U.S.A. and elsewhere, it is evident that it has been collected on additional species of the Onagraceae in other localities also. Until recently, S. fulgens was believed to be the only long-cycled species on members of this family, and nearly all herbarium specimens bear this label. However, in 1954 and 1955, the author found that what had been reported as S. fulgens on Oenothera laciniata (Cook, 1945) and an unidentified species on Epilobiuzm francissicum were quite different from Schroeter's species in that the initial cell of the so-called summer cycle functions as a prosorus instead of sorus. Accordingly, for this and for other reasons he named these species S. brownii and S. epilobii, respectively. The discovery of prosori in these species raised the question whether or not they might be present in the summer cycle of S. fulgens also and had been overlooked by Schroeter and Kusano (1930a, b). To answer this question it was necessary to study carefully collections of S. fulgens from various parts of the world where it has been reported to occur. Accordingly, specimens labeled as S. fulgens were obtained from several herbaria, soaked thoroughly in water, fixed in a vacuum to remove air, embedded, sectioned, and stained. Although such specimens are unfavorable for study of developmental stages because of their dried and shrunken condition, sections of sporangial galls usually reveal evidence of the presence or absence of prosori. As the author (1955a, b) has shown, for many species with prosori, a clearly recognizable plug of densely stainable material is deposited in the former exit pore between the empty prosorus and sorus of sporangial galls and persists as long as the remainder of the herbarium specimens do. The presence of this plug indicates that the initial cell has functioned as a prosorus, although the latter may be empty, collapsed and hardly recognizable as such in herbarium material. The presence of a prosorus is very difficult to detect by dissection of dried herbarium specimens, and cytological tech

Synchytrium brownii was established by Karling (4) for a parasite of Oenothera laciniata in Louisiana which Cook (2) had previously collected and identified as S\ fulgens. Subsequently it was found on 0. biennis in a field in Indiana, and a study of its host range showed that it is capable of infecting a number of other onagraceous species in the greenhouse. As described previously by the author (14), the reac? tion of the majority of these hosts to infection by incipient prosori or resting spores manifests itself primarily by a marked enlargement of the infected cell. This is usually accompanied by division and subse? quent enlargement of the surrounding epidermal, palisade and collenchyma cells causing the development of composite galls. In addition to the reactions of susceptible hosts, abortion reactions occur in some resistant taxa of the Onagraceae, and the present contribution concerns the cytology of these reactions. Somewhat similar abortions have been reported to occur in cases of infection by various species of Synchytrium by Cartwright (1), Koehler (6, 7, 8, 9, 10), Kusano (11, 12, 13), Gaumann (3) and Karling (5). In non-susceptible potato varieties Cartwright found that 5. endobioticum is as capable of infecting such varieties as readily as highly susceptible ones. She discovered that the death of the fungus occurred a few days after it penetrated the host cell; and concluded that resistance, in this case, was not due to mechanical failure of the fungus to enter the cell but to some physiological characteristic of the cell. Koehler (6, 7) continued this work and described the infected and adjacent cells of resistant varieties as undergoing acute or chronic necrotic abortion. In the case of acute abortion the fungus died within a few hours or days; in the latter reaction the parasite died within several weeks. According

The evolutionary origins of permanent translocation heterozygosity remain largely a matter of speculation. Two routes have been posited: (1) interspe- cific or interpopulational hybridization and (2) gradual accumulation of transloca- tions within a population. To test these hypotheses for one such chromosomal het- erozygote, Oenothera laciniata, allozyme data were collected for this species and other members of its subsection. These data show that 0. laciniata is very closely related to the self-incompatible 0. grandis (Nei's D = 0.003), which it resembles in mor- phology and ecology as well. The allozyme data suggest that 0. laciniata is a stabilized hybrid, though not an interspecific one; instead, the data collected here and else- where suggest that 0. laciniata arose more than once as an interpopulational hybrid of 0. grandis.