Herbaceous Annual Research Articles

Study on Government Managed Gardens in Public Buildings of Kathmandu Valley

An area embellished with ornamental plants near the city area and office can give a pleasurable, picturesque and naturalistic effect which creates a refreshing and conducive working environment for both staff and service seekers. A study was carried out to elucidate the existing situation of the government managed gardens in public buildings located in the Kathmandu valley. The gardens were selected purposively and the study was made based on the number of plant species, composition of plants, styles of gardening, maintenance of garden and appreciation of the garden. The maintenance and the appreciation of gardens were evaluated by the Likert scale (1-4). The abundance of tree was higher followed by herbaceous perennial, herbaceous annual, shrub, cacti and succulent. The garden of Narayanhiti Palace Museum was found to be dominant in tree, shrub and herbaceous perennial while the Garden of Singha Durbar and Supreme Court was found to be dominant in herbaceous annual. The frequency of Thuja orientalis (tree), Bougainvillea spp (shrub), Cuphea hyssopifolia (herbaceous perennial), Calendula officinalis (herbaceous annual) and Petunia hybrida (herbaceous annual) were higher. This study shows that formal gardens (66.66%) dominated informal gardens (33.34%). It was found that the maintenance and the overall appreciation of gardens were fair to good. The gardens need improvements in various aspects to make them artistic and beautiful.

A foliar spray application of indole-3-butyric acid promotes rooting of herbaceous annual cuttings similarly or better than a basal dip

Foliar rooting hormone applications containing indole-3-butyric acid (IBA) to unrooted vegetative cuttings have gained popularity as they reduce labor costs and the risk of spreading diseases compared to standard basal dips. The objective of this study was to quantify if foliar applied 20% IBA promotes adventitious rooting of herbaceous annuals similarly to a basal dip application of IBA + 1-napthaleneacetic acid (NAA). Dahlia (Dahlia pinnata) Venti™ ‘Passion Fruit’, osteospermum (Osteospermum ecklonis) Serenity™ ‘Lavender Frost’, scaevola (Scaevola aemula) Scalora® ‘Brilliant’ and geranium (Pelargonium × hortorum) Sunrise™ ‘Lavender + Red Eye’ cuttings received a foliar spray of 0, 150, 300, or 600 mg·L–1 IBA at 0.2 L·m–2; 150 or 300 mg·L–1 IBA at 0.8 L·m–2; or a basal dip of 100 mg·L–1 + 50 mg·L–1 or 200 mg·L–1 + 100 mg·L–1 IBA + NAA. In most cases, cuttings receiving a foliar application of 300 mg·L–1 IBA at 0.8 L·m–2 had either comparable or greater root dry mass than cuttings receiving a basal dip of IBA + NAA and outperformed the control. After 14 d, root dry mass was generally greatest when cutting were treated with 300 mg·L–1 IBA at 0.8 L·m–2 and was an equal or better alternative to a basal dip. For the most effective results, rooting hormones should be utilized when the DLI integral is <12 mol·m–2·d–1.

Simultaneous optimization of ultrasonic-assisted extraction of antioxidant and anticoagulation activities of compounds from Leonurus japonicus Houtt. by response surface methodology.

Leonurus japonicus Houtt. is a herbaceous annual of the Lamiaceae family with pantropical distribution; it is called motherwort in China. It plays important roles in anticoagulation and antioxidation. This study aimed to explore the optimization of ultrasound-assisted extraction of multiple compounds from motherwort as well as their antioxidant and anticoagulation activities using response surface methodology. Box–Behnken design was employed to optimize three significant influences, namely extraction time, extraction temperature and ethanol concentration. The optimum extraction parameters acquired based on a combination of the yield of the target compounds and their antioxidant and anticoagulation activities were an extraction time of 38.2 min, an extraction temperature of 30.0 °C, an ethanol concentration of 48.9% (v/v), a solid–liquid ratio of 30.0 mL g−1 and an ultrasonic power of 500.0 W. Under the optimal conditions, the maximal yield of the anticoagulation and antioxidant compounds of motherwort was 0.994%; the thrombin time was 19.872 s; prothrombin time was 8.270 s; the activated partial thromboplastin time was 15.535 s; the fibrinogen was 1.420 g L−1; and the 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity was 1.503 mg mL−1. The optimized conditions model showed a good correlation between the predicted and experimental values. According to the results of our study, the optimization extraction significantly enabled study of the anticoagulation and antioxidant activities of compounds in motherwort; this may contribute to future research on the pharmacological activities of motherwort.

Growth habit and leaf economics determine gas exchange responses to high elevation in an evergreen tree, a deciduous shrub and a herbaceous annual.

Plant growth at high elevations necessitates physiological and morphological plasticity to enable photosynthesis (A) under conditions of reduced temperature, increased radiation and the lower partial pressure of atmospheric gases, in particular carbon dioxide (pCO2). Previous studies have observed a wide range of responses to elevation in plant species depending on their adaptation to temperature, elevational range and growth habit. Here, we investigated the effect of an increase in elevation from 2500 to 3500 m above sea level (a.s.l.) on three montane species with contrasting growth habits and leaf economic strategies. While all of the species showed identical increases in foliar δ(13)C, dark respiration and nitrogen concentration with elevation, contrasting leaf gas exchange and photosynthetic responses were observed between species with different leaf economic strategies. The deciduous shrub Salix atopantha and annual herb Rumex dentatus exhibited increased stomatal (Gs) and mesophyll (Gm) conductance and enhanced photosynthetic capacity at the higher elevation. However, evergreen Quercus spinosa displayed reduced conductance to CO2 that coincided with lower levels of photosynthetic carbon fixation at 3500 m a.s.l. The lower Gs and Gm values of evergreen species at higher elevations currently constrains their rates of A. Future rises in the atmospheric concentration of CO2 ([CO2]) will likely predominantly affect evergreen species with lower specific leaf areas (SLAs) and levels of Gm rather than deciduous species with higher SLA and Gm values. We argue that climate change may affect plant species that compose high-elevation ecosystems differently depending on phenotypic plasticity and adaptive traits affecting leaf economics, as rising [CO2] is likely to benefit evergreen species with thick sclerophyllous leaves.

Assessment of consumer acceptability and market potential of convenience foods developed from buckwheat (Fagopyrum esculentum)

Common buckwheat (Fagopyrum esculentum) is a broad-leafed herbaceous annual. It belongs to the family Polygonaceae, which is generally referred to as the buckwheat (Soral-CEmietana, 1987). Buckwheat has gained an excellent reputation for its nutritious qualities in the human diet. Its renewed popularity stems from its many bioactive components, which have been shown to provide various health benefits much sought after in natural foods (Eggum and Kreft et al., 1981). Convenience foods are a class of foods which impart convenience to the consumers by way of little or no requirements of major processing or cooking before their consumption. In the present study, consumer acceptability and market potential of convenience foods were assessed. Biscuit, Namkeen, Papad, Pasta, Idli mix were prepared through incorporation of buckwheat whole flour. Consumer acceptability and market potential were assessed through interview schedule. It was found that ready to eat foods as Biscuit and Namkeen were preferred more by consumers and shopkeepers as compared to ready to cook food and Idli mix.

The Biology of Canadian weeds. 150 Erechtites hieraciifolius (L.) Raf. ex DC.

Darbyshire, S. J., Francis, A., DiTommaso, A. and Clements, D. R. 2012. The Biology of Canadian weeds. 150 Erechtites hieraciifolius (L.) Raf. ex DC. Can. J. Plant Sci. 92: 729–746. Erechtites hieraciifolius, American burnweed, is a herbaceous annual in the Asteraceae native to forest zones of eastern North America, but introduced to parts of Europe and the Pacific region. Confusion sometimes arises in distinguishing it from other weedy rayless composites in Canada, such as Senecio vulgaris (common groundsel) and Conyza canadensis (Canada fleabane). A pioneer therophyte species of forest zones, it occurs in large numbers when associated with major disturbances such as forest fires, but is also common in areas of smaller scale disturbance such as shores, forest edges and wind-throws. Soil conditions may vary greatly in nutrient content, moisture content, pH and salinity. In Canada, it is generally considered a minor garden and agricultural weed. It is most common in crops such as lowbush blueberry (Vaccinium spp.), cranberry (Vaccinium macrocarpon), strawberry (Fragaria×ananassa) and vegetable crops; however, it occasionally occurs in other field and forage crops. Impacts include a variety of problems contributing to increased production costs or crop yield losses, including herbicide resistance, resource competition, and as a reservoir harbouring crop pathogens. It has been valued as a medicinal herb for treating a variety of ailments. Populations may grow rapidly in response to disturbances typical of managed landscapes, but E. hieraciifolius can usually be effectively controlled by chemical, cultural or manual weed control tactics.

Population Differentiation of Impatiens capensis (Balsaminaceae) at the Range Limit

A plant species that occupies a large geographic range must survive in a variety of environments. Impatiens capensis, an herbaceous annual that grows contiguously from the east coast of North America to the Colorado Rocky Mountains, prefers moist environments and is easily susceptible to drought. Impatiens populations at the species’ western range limit (Colorado) must endure a dramatically different environment than eastern populations do (Rhode Island and Illinois). This study investigated the stress response of a weedy annual at its range limit by examining how regional populations of I. capensis morphologically, physiologically, and phenologically adjust to drought. The results suggest that each population has evolved along a different evolutionary axis; each population exhibits a unique strategy for responding to drought stress. Rhode Island populations have evolved along a temporal axis to avoid stress with an accelerated phenology. An Illinois population has evolved along a physiological axis and exhibits a drought-tolerance strategy. Colorado populations have evolved along a morphological axis and tolerate drought. Thus, dealing with drought stress may involve population differentiation along different axes of functional plasticity.

The glycine decarboxylase complex multienzyme family in Populus

In plants, the glycine decarboxylase complex (GDC) cooperates with serine hydroxymethyltransferase (SHMT) to mediate photorespiratory glycine-serine interconversion. GDC is also postulated to be an integral component of one-carbon (C1) metabolism in heterotrophic tissues, although molecular evidence in plants is scarce. An initial report of a xylem-specific isoform of GDC component H-protein, PtgdcH1, in aspen (Populus tremuloides Michx.) provided molecular evidence consistent with an important role for GDC in plant C1 metabolism. PtgdcH1 is phylogenetically distinct from the leaf-abundant photorespiratory PtgdcH3, but both isoforms restored GDC activity in a yeast H-protein knockout mutant, suggesting their functional equivalence. The Populus genome contains eight transcriptionally active GDC genes, encoding four H-proteins, two T-proteins, and single P- and L-proteins. The two Populus T-protein isoforms, PtgdcT1 and PtgdcT2, exhibited differential expression in leaves and xylem, similar to PtgdcH3 and PtgdcH1. In silico identification of AC elements in the promoters of xylem-abundant PtgdcH1 and PtgdcT2, as well as many lignin biosynthetic genes of Populus is consistent with a prominent role for GDC in methyl-intensive lignification during wood formation. The AC element is absent from Arabidopsis GDC promoters, and GDC expression has not been linked to secondary growth in this herbaceous annual. Taken together, the results suggest that the association of distinct H-protein and T-protein isoforms with photorespiration and C1 metabolism is a distinguishing feature of Populus, and may signify molecular adaptation of GDC to cope with the C1 demands of lignification in woody perennials.

Performance of Selected Herbaceous Annual Ornamentals Grown at Decreasing Levels of Irrigation

This study was conducted to evaluate the growth, visual quality, and stress response of 17 species of bedding plants and Kentucky bluegrass (Poa pratensis L.) grown outdoors for 10 weeks during the summer of 2003 at three locations in Colorado. Plants were irrigated at 100% of the reference evapotranspiration (ET0) (amount required to maintain Kentucky bluegrass in an optimum condition) for 2 weeks followed by 8 weeks at five irrigation levels: 0%, 25%, 50%, 75%, and 100% ET0. Begonia carrieri Hort. `Vodka', Lobelia erinus L. `Cobalt Blue', and Viola ×wittrockiana Gams. `Crown Gold' grew well with a minimum of 50% or more ET0 based on Kentucky bluegrass. Impatiens walleriana Hook. fil. `Tempo White' grew well only with 100% ET0. Antirrhinum majus L. `Sonnet Yellow', Dianthus L. `First Love', Lobularia maritima (L.) Desv. `Carpet White', and Pelargonium ×hortorum L.H. Bailey performed well with 25% to 50% ET0. The species Catharanthus roseus (L.) G. Don `Peppermint Cooler', Rudbeckia hirta L. `Indian Summer', Senecio cineraria D.C. `Silver Dust', Tagetes erecta L. `Inca Yellow' and T. patula L. `Bonanza Gold', Zinnia angustifolia Kunth., and Salvia farinacea Benth. `Rhea Blue', which are adapted to midsummer heat and low water, performed well with 0% to 25% ET0. Species considered to be heat or drought tolerant—Petunia ×hybrida hort. ex. E. Vilm. `Merlin White' and Glandularia J.F. Gmel. `Imagination'—required little or no irrigation. The bedding plant species evaluated in this study that required 25% or less ET0 are well adapted for low-water landscape installations.

A review of the biology and ecology of Florida beggarweed (Desmodium tortuosum)

Florida beggarweed is native to the Western Hemisphere but is naturalized around the world. During the last century, the mechanization of agriculture has transitioned Florida beggarweed from an important forage component to a weed of significance in the coastal plain of the southeast United States. This herbaceous annual is naturalized and found in fields and disturbed areas throughout the southern United States. The characteristics that made Florida beggarweed a good forage crop also make it a formidable weed. This review describes the importance of Florida beggarweed as a weed in the southern United States and the taxonomy of this species and details the distribution throughout the world and within the United States. The ecology of Florida beggarweed and its interactions with crop plants, insects, nematodes, and plant pathogens also are summarized. Finally, management of Florida beggarweed in agricultural systems using cultural practices and herbicides is reviewed.

Night-time conductance in C3 and C4 species: do plants lose water at night?

Significant night-time stomatal conductance and transpiration were found for 11 out of 17 species with a range of life histories (herbaceous annual, perennial grass, shrub, tree), photosynthetic pathways (C(3), C(4)), and habitats in the western United States. Across species and habitats, higher night-time conductance and transpiration were associated with higher daytime values. The prevalence, mechanisms and ecological implications of substantial night-time water loss deserve further investigation.

Competitive Ability of Alliaria petiolata (Garlic Mustard, Brassicaceae), an Invasive, Nonindigenous Forest Herb

Alliaria petiolata (Bieb.) Cavara & Grande (garlic mustard, Brassicaceae) is a Eurasian herb that is currently invading forested areas throughout portions of the northern United States and southern Canada. Alliaria petiolata enters plant communities in an aggressive fashion, often displacing resident understory species. One possible mechanism that may enable garlic mustard to successfully invade these areas is hypothesized superiority as a competitor. In order to determine the competitive potential of A. petiolata, a multiple deWit replacement series was conducted in the greenhouse between A. petiolata and three native species: Impatiens capensis, an herbaceous annual, and Acer negundo and Quercus prinus, two woody perennials. Each target species was grown in mixture with A. petiolata, and all species were grown in monoculture. After 21 wk, plants were harvested and dried. Aboveground dry‐weight biomass (yield) was then used to calculate the relative yield per plant, relative yield total, and mean aggress...

Changes in mass and chemistry of plant roots during long-term decomposition on a Chihuahuan Desert watershed

We studied the spatial and temporal patterns of decomposition of roots of a desert sub-shrub, a herbaceous annual, and four species of perennial grasses at several locations on nitrogen fertilized and unfertilized transects on a Chihuahuan Desert watershed for 3.5 years. There were few significant differences between the decomposition rates of roots on the NH4NO3 fertilized and unfertilized transects. Decomposition of all roots followed a two-phase pattern: early rapid mass loss followed by a long period of low mass loss. Rates of decomposition were negatively correlated with the initial lignin content of the roots (r=0.90). Mass loss rates of the roots of the herbaceous annual, Baileya multiradiata, were significantly higher than those of the grasses and the shrub, probably as a result of subterranean termites feeding on B. multiradiata root material. The only location where mass loss rates were significantly different was the dry lake bed, where mass loss rates were lower than those recorded on the upper watershed. The spatial differences in mass loss rates in the dry lake were attributable to the high clay content of the soils, which reduced water availability, and to the absence of termites. Non-polar substances in decomposing roots decreased rapidly during the first year, then decreased at a low but fairly constant rate. Water-soluble compounds decreased rapidly (50–60% of initial concentration) during the first 3–6 months. Lignin concentrations of roots of perennial grasses were higher than those of herbaceous annual plants and woody shrubs. Lignin concentrations increased in all species during decomposition. The chemical changes in decomposing roots followed the patterns described for decomposing litter in mesic environments.

Intraspecific variation in seed dispersion of Lepidium campestre (Brassicaceae)

Intraspecific variation in seed dispersion provides the initial context for frequency‐dependent and density‐dependent processes affecting seed/seedling survival. We examined intraspecific variation in seed dispersion in a ballistically dispersed herbaceous annual, Lepidium campestre, in both the presence/absence of vegetation to determine the magnitude of variation in seed dispersion among parents, the relationship of this variation to parental architecture, and the effect of the presence of vegetation both on the variation and on its relationship to parental architecture. We quantified seed dispersion by placing concentric rings of traps around individual parents out to a distance of 2 m in the presence/absence of vegetation in an old‐field plant community. In the absence of vegetation, parents differed in the distance and direction that their seeds traveled. Parental height and infructescence length explained a significant proportion of the variation in mean and standard deviation of seed dispersal distance, as well as skewness and kurtosis of the distribution of seed number as a function of distance. The mean direction that seeds traveled was correlated with all architectural traits. When plants dispersed their seeds in sites with dense vegetation, mean dispersal distance and standard deviation in distance decreased, and dispersal distributions were more right‐skewed and leptokurtic. The presence/absence of vegetation explained some of the variation among parents in the moments of the distance distribution, but architectural traits also contributed to these descriptive models. Directional components of dispersal were not affected by vegetation. Correspondence analysis, a multivariate technique that examined distance and direction simultaneously, revealed that architectural attributes related to variation in dispersion were different from analyses of distance alone. These results suggest that architectural attributes of the parent contribute not only to the distance that seeds travel, but also to other axes of variation, i.e., skewness and kurtosis of the distance distribution or multivariate axes of seed dispersion. Surrounding vegetation alters seed dispersion, but parental attributes can still explain some of the residual variation. This variation in seed dispersion among parents creates the opportunity for selection on parental dispersal traits.

Decomposition of roots in a Chihuahuan Desert ecosystem.

Mass losses of tethered buried roots of two woody shrubs and two herbaceous annuals buried in plots irrigated at 25 mm·month-1, 6 mm·week-1 and no irrigation were measured. At the end of 1 year, 10-15% of the mass of the herbaceous annual roots remained and 60% of the mass of woody shrub roots remained. There were no differences in mass loss attributable to added water. Rates of mass losses of roots in the Chihuahuan Desert were equal to or higher than those reported from mesic ecosystems. Roots of woody shrubs had relatively constant C:N ratios through the experiment. There was significant N immobilization in Baileya multiradiata roots. Percent mass loss of grass roots, Erioneuron pulchellum, and herbaceous annual roots, B. multiradiata, in plots with termites was 62% and in plots without termites was 15%. These data suggest that subterranean termites are responsible for most of the mass loss and mineralization of carbon and nitrogen in dead grass and herbaceous roots in the northern Chihuahuan Desert.

Increased Arginine Biosynthesis during Phosphorus Deficiency

The accumulation of arginine in leaves of four citrus rootstock cultivars during P deficiency has been demonstrated to be due to increased de novo synthesis rather than decreased catabolism or increased protein degradation (E Rabe, CJ Lovatt, 1984, Plant Physiol 76: 747-752). In this report, we provide evidence (a) that the increased activity of the arginine biosynthetic pathway observed for citrus rootstocks grown under P-deficient conditions for 7 months is due to an increase in the concentration of ammonia in leaves of P-deficient plants and (b) that ammonia accumulation and removal through arginine systhesis are early responses to phosphorus deficiency for both a woody perennial, rough lemon (Citrus limon), and an herbaceous annual, summer squash (Cucurbita pepo). Transferring 5-day-old squash plants to a phosphorus-deficient nutrient solution for only 10 days resulted in a 2-fold increase in the concentration of nitrate in the youngest fully expanded leaves (YFE). Concomitantly, the specific activity of nitrate reductase doubled and the ammonia content of P-deficient YFE leaves increased to a concentration significantly greater that of leaves from healthy control plants (P < 0.05). Consistent with increased availability of ammonia, the incorporation of NaH(14)CO(3) into arginine plus urea doubled during phosphorus deficiency and arginine accumulated. Despite the accumulation of nitrate and ammonia in YFE leaves during phosphorus deficiency, the total nitrogen content of these leaves was less than that of the healthy control plants. Similar results were obtained for rough lemon. Nitrate content of the YFE leaves increased 1.5- and 3.0-fold in plants deprived of phosphorus for 6 and 12 weeks, respectively. Ammonia content of the leaves increased as P deficiency progressed to 1.4 +/- 0.08 mg (+/- se, n = 4) per gram dry weight, a level 1.8-fold greater than that of the P-sufficient control plants. During P deficiency de novo arginine biosynthesis in rough lemon increased 10-fold. Immersing the petiole of YFE leaves from P-sufficient squash and rough lemon plants in 50 millimolar NH(4) (+) for 3 hours resulted in the accumulation of ammonia in the leaves, and a 4-fold increase in the incorporation of NaH(14)CO(3) into arginine plus urea. Taken together, these results provide strong evidence that the accumulation of nitrate and ammonia in leaves is an early response of both woody and herbaceous plants to P deprivation. The data are consistent with the hypothesis that increased de novo arginine biosynthesis in leaves during P deficiency is in response to ammonia content of the leaves.

QUANTITATIVE GENETICS OF SURVIVAL AND GROWTH IN IMPATIENS CAPENSIS.

When variation in life-history characters is caused by many genes of small effect, then quantitative-genetic parameters may quantify constraints on rate and direction of microevolutionary change. I estimated heritabilities and genetic correlations for 16 life-history and morphological characters in two populations of Impatiens capensis, a partially self-pollinating herbaceous annual. The Madison population had little or no additive genetic variance for any of these characters, while the Milwaukee population had significant narrowsense heritabilities and genetic correlations for several traits, including adult size, which is highly correlated with fitness. All genetic correlations among fitness components were positive, hence there is no evidence for antagonistic pleiotropy among these traits. Dissimilarity of heritabilities in the two populations supports theoretical predictions that long-term changes in genetic variance-covariance patterns may occur when population sizes are small and selection is strong, as may occur in many plant species.

Diversity Relations and Succession in Californian Coastal Sage Scrub

The facultatively drought—deciduous shrublands of coastal California and Baja California are lowest in species richness of the four Mediterranean—climate regions where this physiognomic type occurs. Alpha richness in the North American coastal sage scrub varies primarily with the abundance of herbaceous annual species. Herb levels in turn vary with differences in levels of precipitation, favorableness of temperature during the winter and spring growing season, shading by shrubs, soil nitrogen, and air pollution. Levels of herbaceous annuals are highest in the growing season following fire, and show a second pulse of abundance in stands 15—25 yr old. Mature stands of coastal sage scrub are typically low in species equitability, due at least in part to the shade—intolerance of the herbaceous understory and to reduced levels of soil nitrogen. Symbiotic nitrogen—fixing organisms are virtually absent from stands which have not burned in 20 yr or more. The pattern of postfire succession varies markedly with fire intensity; dominant shrubs sprout abundantly from root crowns only following less intense fires. While there are °50 widespread sage scrub species, more than half of the 375 species encountered in the present study of the sage scrub flora are rare in occurrence within the habitat range. In view of the reduction of the area of coastal sage scrub in California to 10—15% of its former extent and the limited extent of preserves, measures to conserve the diversity of the flora are needed.

Kenaf Versus Forests as a Source of Paper Pulp

SUMMARY Kenaf (Hibiscus cannabinus L.), an herbaceous annual, is a potential source of raw material for the pulp industry. It is adapted to warm growing conditions and is capable of high productivity. Pulping tests have shown that the bark and wood fractions of the stem can be pulped by conventional processes to give pulps comparable with commercial wood pulps. The seed and the leaves could also be valuable by-products. A preliminary appraisal of its potential is made on the basis of field trials conducted at Kimberley Research Station in the Ord Irrigation Area. Comparisons are made with forests in relation to productivity, production economics, land resources and environmental impact. It is concluded that there are reasonable prospects of kenaf being grown profitably under irrigation in northern Australia if it could be sold at the present U.S.A. f.o.b. price for woodchips. However, profitable production would require utilisation of the leaves and seed.