Sicyos Angulatus Research Articles

Genetic diversity of Sicyos angulatus in central and north‐eastern Japan by inter‐simple sequence repeat analysis

SummaryFor the development of effective procedures to control invasive plants, it is necessary to learn about their mechanism of spread, for which an understanding of the plant’s genetic variation may be important. Sicyos angulatus is a widespread and invasive weed that grows among forage crops and natural vegetation in Japan. Inter‐simple sequence repeat (ISSR) genotyping was used to detect the regional patterns of genetic variation of S. angulatus in its introduced range in Japan. The goal of this research was to assess the introduction dynamics and mechanism of spread of S. angulatus in Japan. Four screened ISSR primers produced 15 reliable bands, and 12 of these were polymorphic among six areas in central and north‐eastern Japan. The analysis of molecular variance (amova) revealed that 88.4% of genetic variation occurred within areas rather than between the two regions (1.1%), or among areas within regions (10.5%). While the total gene diversity among areas (Ht) was 0.1684, the coefficient of gene differentiation was low among two geographically distinct regions (Gst = 0.053). The genetic diversity indices (h = 0.116; I = 0.173) of the Fuji river area, assumed to be near the first introduction site, were not higher than other areas (total h = 0.165; total I = 0.263). In contrast, those of the Chikuma river and Tenryu river areas were relatively high (h = 0.173 and 0.187; I = 0.276 and 0.277 respectively). The Mantel test showed no significant correlation between geographical and genetic distances. These results suggest multiple introductions from the same gene pools into both central and north‐eastern regions of Japan.

Extension and seasonal characteristics of Sicyos angulatus community on Kamitsu area of Inagawa-River.

Extension and seasonal characteristics of Sicyos angulatus community on Kamitsu area of Inagawa-River.

Chemical factors influencing the feeding preference of three Aulacophora leaf beetle species (Coleoptera: Chrysomelidae)

Three cucurbitaceous feeding leaf beetle species, Aulacophora indica, A. lewisii, and A. nigripennis, were investigated with regard to the relationship between feeding preference by the beetles and cucurbitacins B, E, I, and E-glucoside contents in the leaves of 18 cucurbitaceous plant species. HPLC analysis and TLC analysis of A. lewisii revealed that the cucurbitacin B and E-glucoside, which are strong feeding stimulants for A. indica and A. lewisii, were abundant in Lagenaria siceralia, Sicyos angulatus, and Cucumis melo leaves. In a feeding preference test using fresh leaves, A. indica preferred various cucurbitaceous plant species and methanol extracts regardless of the contents of the four cucurbitacins. A. lewisii mostly fed on Luffa cylindrica leaves in which the four cucurbitacins were not detected. A. lewisii was also stimulated to feed by the methanol extracts of Lagenaria siceraria and L. cylindrical, while A. nigripennis, which is only slightly stimulated to feed by the four cucurbitacins, fed primarily on Trichosanthes kirilowii var. japonica leaves. Among 18 cucurbitaceous plants, only Diplocyclos palmatus leaves were completely rejected by the three beetle species, and these beetle species did not even feed on D. palmatus leaves treated with the cucurbitacins. These results indicate that some leaf constituents as well as the four cucurbitacins play an important role in host plant selection by the three cucurbitaceous feeding beetle species.

Effect of Tillage, Row Spacing, and Herbicide on the Emergence and Control of Burcucumber (Sicyos angulatus) in Soybean (Glycine max)1

An experiment was conducted in 1998 and 1999 in southeastern Pennsylvania to examine the effect of tillage and soybean row spacing on burcucumber emergence and growth. A second experiment evaluated postemergence (POST) soybean herbicides on burcucumber control. In the tillage and row spacing study, a glyphosate-resistant soybean variety was planted in no-till and reduced-tillage systems in 38- and 76-cm row spacings. In the POST herbicide experiment, chlorimuron, glyphosate, CGA-277476, thifensulfuron, and several combinations of these herbicides were applied at two different POST application timings in 38-cm row soybean planted in a reduced-tillage system. In the tillage and row spacing study, burcucumber emergence was greatest starting in late May through mid-June and mostly ceased by early July, regardless of tillage system or row spacing. Although there was no difference in germination period in either tillage system, preplant tillage increased the number of emerged plants by 110% in 1997 and 70% in 1998 compared to the no-till system. Row spacing had no effect on burcucumber emergence or biomass production. In general, most POST herbicide programs controlled burcucumber, and there was no difference between early POST and mid-POST application timings. Chlorimuron at 13 g ai/ha, chlorimuron plus thifensulfuron, glyphosate, glyphosate plus chlorimuron, and glyphosate plus CGA-277476 provided 87% or greater control of burcucumber 12 wk after planting. These herbicides reduced burcucumber density and biomass by more than 56% in 1997 and 96% in 1998.Nomenclature: CGA-277476 (proposed name, oxasulfuron), 2-[[[[[4,6-dimethyl-3-pyrimidinyl]amino]carbonyl]amino] sulfonyl]benzoic acid, 3-oxetanyl-ester; chlorimuron; glyphosate; thifensulfuron; burcucumber, Sicyos angulatus L. #3 SIYAN; soybean, Glycine max (L.) Merr.Additional index words: Cultural control, emergence period, herbicide application timing, herbicide-resistant crops.Abbreviations: EPOST, early postemergence; GDD, growing degree days; LPOST, late postemergence; MPOST, mid-postemergence; POST, postemergence; WAP, weeks after planting.

Tillage and Herbicides Affect Burcucumber Management in Corn

The effect of tillage and herbicide application timing was examined on established populations of burcucumber (Sicyos angulatus L.) in corn (Zea mays L.). The field study consisted of three tillage regimes (moldboard plow/disk, chisel plow/disk, and no‐tillage) and three herbicide treatments: atrazine [6‐chloro‐N‐ethyl‐N′‐(1‐methylethyl)‐1,3,5‐triazine‐2,4‐diamine] plus the dimethylamine salt of dicamba; 3,6‐dichloro‐2‐methoxybenzoic acid applied preemergence (PRE) or postemergence (POST); and no atrazine plus dicamba (no broadleaf herbicide). Postemergence treatments were applied to 3‐ to 6‐leaf corn and cotyledon to 8‐leaf burcucumber. In two of three field locations, late‐season burcucumber dry weight was approximately 65% less in no‐tillage than in the moldboard plow treatment, while no difference in burcucumber dry weight was observed between chisel plow and no‐tillage treatments. Regardless of tillage system, atrazine plus dicamba applied POST was more effective than PRE applications. Corn grain yield was not affected by tillage treatment, but was higher in both the PRE and POST treatments than in the no broadleaf herbicide treatment. Depth of burcucumber seedling emergence was examined in the greenhouse. Pre‐germinated burcucumber seeds were placed in the soil at 0, 1, 3, 5, 10, 15, and 20 cm deep. Percent emergence was highest in the 1 to 5 cm depth. Less burcucumber emerged from depths of 10 cm or greater or when burcucumber was placed on the soil surface. These data suggest that tillage and herbicide timing can influence burcucumber control.

Evaluation of Several Herbicides for Burcucumber (Sicyos angulatus) Control in Corn (Zea mays)

A postemergence (POST) timing study was conducted on established populations of burcucumber (Sicyos angulatus) in corn (Zea mays), and a second study examined the residual activity of several herbicides for burcucumber control under greenhouse conditions. In the field study, flumiclorac, halosulfuron, primisulfuron, CGA 152005, and CGA 152005 + primisulfuron (45, 71, 40, 40, and 20 + 20 g ai/ha, respectively) were applied at two POST timings. CGA 152005, primisulfuron, and the combination provided greater than 85% control of burcucumber 14 wk after planting (WAP). Flumiclorac and halosulfuron provided 60% control or less by 8 WAP. Timing of the POST applications did not influence burcucumber control by 11 WAP with any herbicide. In the greenhouse, germinated burcucumber seeds were placed in soil treated with atrazine, chlorimuron, primisulfuron, or CGA 152005 at normal field use rates. All treatments provided similar residual control early; however by 4 wk after treatment (WAT), control from atrazine was less than 10% compared to 69% for chlorimuron and about 50% for primisulfuron and CGA 152005. This research suggests that CGA 152005 and primisulfuron can both be effective for managing burcucumber in corn, whereas flumiclorac and halosulfuron proved ineffective.

The Effect of Low Root Temperature on Growth and Lipid Composition of Low Temperature Tolerant Rootstock Genotypes for Cucumber

In the framework of research directed to diminish energy consumption of glasshouse cucumber production, three low temperature tolerant rootstock genotypes for cucumber were compared. Firstly, growth at low root temperature of one Cucurbita ficifolia and two Sicyos angulatus genotypes was studied to determine which was the one most suitable as a cucumber rootstock at suboptimal root temperatures. Secondly, differences in lipid composition were examined. Thirdly, lipid composition of these rootstock genotypes was compared with that of low temperature sensitive cucumbers (Cucumis sativus L.; cv. Farbio and CPO inbred lines 79345 and 81354) studied earlier, to determine whether observed differences in lipid composition were consistent with differences in growth at low temperature of related species. Plants were grown at an air temperature of 20-degrees-C d/12-degrees-C n and at constant root temperatures of 20-degrees-C, 16-degrees-C or 12-degrees-C. Although growth decreased at 12-degrees-C for all genotypes, both Sicyos angulatus genotypes were more tolerant to low root temperature than Cucurbita ficifolia. Low root temperature affected root lipid composition only. An increased phospholipid and a markedly lower sterol and sterol ester level resulted in a strongly decreased sterol/phospholipid ratio at 12-degrees-C. Growth at low root temperature was inversely related with the sterol/phospholipid ratio but no correlation between growth and sterol/phospholipid ratio of the rootstock genotypes within one temperature regime was observed. So, this ratio is not an appropriate selection criterion for growth capacity.

24-Methylene-25-methyllathosterol: A sterol from Sicyos angulatus

A new sterol isolated from the aerial parts of Sicyos angulatus has been shown to be 24-methylene-25-methyllathosterol.

Rinvenimenti floristici in Piemonte

Abstract New discoveries concerning the Piedmont Flora. – The Author's research on the Piedmont Flora – corried on from 1969 up to 1974 – led to the discovery of new stations of the following entities, that are to be considered of special interest for the Flora in Piedmont. Here they are: Cyperus strigosus L.; Scirpus atrovirens Willd.; Platanus orientalis L.; Ulmus levis Pall.; Rumex paluster Sm. (= Rumex maritimus L. var. limosus (Thuill.); Mollugo verticillata L.; Cardamine flexuosa Wth.; Diplotaxis erucoides DC.; Spiraea japonica L.; Physocarpus opulifolius (L.); Potentilla supina L.; Acer saccarinus L.; Impatiens glandulifera Royle; Euphorbia prostrata Ait.; Euphorbia humifusa W.; Sicyos angulatus L.; Cyclamen hederifolium Aiton; Erigeron karwinskyanus DC. var. mucronalus DC.; Artemisia annua L.; Siegesbekia orientalis L.; Bidens frondosa L.; Ambrosia trifida L. On the ground of the present contribution it results that some species – considered as rare or at least not very numerous in Piedmont – are probably more frequent than it was known in the past. The Author's assumption that some of them – seen along the streams – are more widely distributed should proverright.

Detoxification of 2,4-D by Several Plant Species

The amount of free, unaltered (2,4-dichlorophenoxy) acetic acid (2,4-D) in resistant and susceptible plant species 1, 4, and 8 days after treatment was determined by three procedures. Centrifugation and chromatography of plant homogenates was a more reliable assay than trichloroacetic acid (TCA) precipitation or dialysis procedures. The foliar penetration of 14C-2-4-D and radioactivity which moved from roots into the growth media following foliar application of 14C-2,4-D varied from one plant species to another, but no general correlations with 2,4-D resistance was observed. The resistant burcucumber (Sicyos angulatus L.) and oats (Avena sativa L.) were not fatally injured primarily because unaltered 2,4-D was immobilized in the treated leaves and unaltered, free 2,4-D was reduced to nontoxic concentrations. The 2,4-D in susceptible cocklebur (Xanthium sp.) remained largely as free and mobile 2,4-D, and the treated plants were near death 8 days after treatment.