Indigenous sward restoration by oversowing Microlaena stipoides into kikuyu (Pennisetum clandestinum) pasture

Management plans for the grazed parklands of the Auckland volcanic cones call for revegetation to restore a more natural and historic vegetation cover. The native grass Microlaena stipoides has been identified as a relevant species, and a field experiment was undertaken to determine the best approach for establishing this species into existing pasture. Seed obtained locally was broadcast or hydro-seeded in May 2007 onto kikuyu pasture, at three sowing rates (100, 250 and 750 seeds/m2) following control of the resident pasture with turf stripping or mowing and spraying, in a replicated factorial trial. After 12 months, the highest levels of Microlaena plant density (mean 56 plants/m2), cover (mean 50%) and accumulated herbage mass were observed on broadcast/sprayed plots at the highest sowing rate. Recovery of the resident pasture (dominantly Pennisetum clandestinum) occurred to a level of ~25% after 12 months, but was inhibited at the highest Microlaena sowing rate. Keywords: broadcast, hydro-seeding, kikuyu, Microlaena stipoides, re-vegetation

Download Full-text

Early productivity and crude protein content of establishing forage swards composed of combinations of native grass and legume species in mixed-grassland ecoregions

Canadian Journal of Plant Science ◽

10.4141/cjps2012-261 ◽

2013 ◽

Vol 93 (3) ◽

pp. 445-454 ◽

Cited By ~ 10

Author(s):

Jenalee M. Mischkolz ◽

Michael P. Schellenberg ◽

Eric G. Lamb

Keyword(s):

Protein Content ◽

Crude Protein ◽

Plant Density ◽

Warm Season ◽

Forage Yield ◽

Schizachyrium Scoparium ◽

Legume Species ◽

Crude Protein Content ◽

Native Grass ◽

Western Wheatgrass

Mischkolz, J. M., Schellenberg, M. P. and Lamb, E. G. 2013. Early productivity and crude protein content of establishing forage swards composed of combinations of native grass and legume species in mixed-grassland ecoregions. Can. J. Plant Sci. 93: 445–454. We evaluated the early establishment productivity of forage swards of native, perennial, cool and warm season grasses, and legumes as they have the potential to provide non-invasive, productive, and drought resistant rangelands. Seven species with agronomic potential and a broad native geographic distribution were selected for testing including: nodding brome [Bromus anomalus (Coult.)], blue bunch wheatgrass [Pseudoregneria spicata (Pursh)], western wheatgrass [Pascopyrum smithii (Rydb.)], side oats grama [Bouteloua curtipendula (Michx.)], little blue stem [Schizachyrium scoparium (Michx.)], purple prairie clover [Dalea purpurea (Vent.)], and white prairie clover [Dalea candida (Willd.)]. Forage swards, including all seven monocultures, 21 two-species mixtures and a mixture with all species, were planted in two sites, Saskatoon and Swift Current, Saskatchewan. Western wheatgrass (WWG) had the highest overall plant density and the strongest effect on the forage yield of the forage swards; however, productivity and crude protein content were not reduced when other species were also included in the forage sward. Dalea spp. did not establish as well as the other species, but had the highest crude protein concentrations. This work provides insight into forage sward development at the establishment stage; additional work is required to determine long-term species impacts for well established forage swards.

Download Full-text

Quantitative genetics of response to competitors in Nemophila menziesii: a field experiment.

Genetics ◽

10.1093/genetics/139.1.397 ◽

1995 ◽

Vol 139 (1) ◽

pp. 397-406 ◽

Cited By ~ 6

Author(s):

R G Shaw ◽

G A Platenkamp ◽

F H Shaw ◽

R H Podolsky

Keyword(s):

Field Experiment ◽

Genetic Variance ◽

Plant Density ◽

Additive Genetic Variance ◽

Natural Populations ◽

Plant Size ◽

Heterogeneous Environments ◽

Environmental Complexity ◽

Sources Of Variation ◽

Nemophila Menziesii

Abstract Recent investigations of evolution in heterogeneous environments have begun to accommodate genetic and environmental complexity typical of natural populations. Theoretical studies demonstrate that evolution of polygenic characters depends heavily on the genetic interdependence of the expression of traits in the different environments in which selection occurs, but information concerning this issue is scarce. We conducted a field experiment to assess the genetic variability of the annual plant Nemophila menziesii in five biotic regimes differing in plant density and composition. Significant, though modest, additive genetic variance in plant size was expressed in particular treatments. Evidence of additive genetic tradeoffs between interspecific and intraspecific competitive performance was found, but this result was not consistent throughout the experiment. Two aspects of experimental design may tend to obscure genetically based tradeoffs across environments in many previously published experiments: (1) inability to isolate additive genetic from other sources of variation and (2) use of novel (e.g., laboratory) environments.

Download Full-text

The influence of floral morph ratios and low plant density on mating and fertility in a tristylous colonizing species

Botany ◽

10.1139/cjb-2018-0032 ◽

2018 ◽

Vol 96 (8) ◽

pp. 533-545 ◽

Cited By ~ 1

Author(s):

Christopher M. Balogh ◽

Spencer C.H. Barrett

Keyword(s):

Field Experiment ◽

Seed Set ◽

Plant Density ◽

Pollen Limitation ◽

Lythrum Salicaria ◽

Long Distance ◽

Experimental Conditions ◽

Wide Range ◽

Morph Ratios ◽

Floral Morph

Sexual reproduction in heterostylous populations may be vulnerable to demographic conditions because of the small number of mating types in populations. Here, we investigate mating and fertility under natural and experimental conditions in tristylous Lythrum salicaria L., an invasive species that exhibits a wide range of floral morph ratios and demographic contexts. We grew 147 open-pollinated seed families from six populations with different morph structures to estimate intermorph mating (d). In a field experiment, we used progeny ratios from 47 spatially isolated individuals to estimate d, and measured the intensity of pollen limitation experienced by the morphs. The M- and S-morphs experienced high rates of d, regardless of population size or morph ratio. Estimates for the L-morph revealed low levels of intramorph mating in three dimorphic and two trimorphic populations, but near complete intramorph mating in a monomorphic population. Despite high levels of intermorph mating in the field experiment, the morphs experienced significant pollen limitation of fruit and seed set, but this did not differ in intensity among the morphs. Our field experiment demonstrates that although plant isolation was associated with pollen limitation of seed set, “long-distance” bee-mediated pollen flow served to maintain intermorph mating. Tristyly in L. salicaria is remarkably robust to the demographic variation associated with colonization.

Download Full-text

Effects of host-plant density on herbivores and their parasitoids: A field experiment with a native perennial legume

10.1603/ice.2016.108384 ◽

2016 ◽

Author(s):

Andrea Salas

Keyword(s):

Field Experiment ◽

Host Plant ◽

Plant Density ◽

Host Plant Density ◽

Perennial Legume

Download Full-text

Evaluation of legumes for introduction into native grass pastures on the North-west slopes of New South Wales

Australian Journal of Experimental Agriculture ◽

10.1071/ea9940449 ◽

1994 ◽

Vol 34 (4) ◽

pp. 449 ◽

Cited By ~ 7

Author(s):

RD FitzGerald

Keyword(s):

Plant Density ◽

New South ◽

New South Wales ◽

Subterranean Clover ◽

Soil Types ◽

Native Grass ◽

Lower Altitude ◽

North West ◽

The North ◽

South Wales

A range of pasture legumes was either broadcast or drilled into native grass pastures on the North-west Slopes of New South Wales to identify legumes that would persist in that environment and improve the quality of winter pastures based on native grasses. There were 2 experiments conducted over 12 sites. In the first, sites were selected to permit identification of effects of altitude and 2 soil types on legume adaptation. In the second, the lower altitude range was extended and a wider range of soil types was sampled. Subterranean clover (Trifolium subterraneum L.) was the most persistent and productive species, with cultivar performance varying with altitude. At the lowest altitude (340 m) the early-maturing cv. Dalkeith was the most productive, and at 500-600 m there was little difference between the tested cultivars. Stand density, herbage yield, and seed yield all declined as altitude increased, but the decline was greater with earlier maturing cultivars than with the later maturing cv. Woogenellup White clover (T. repens cv. Haifa) established poorly in native grass swards, but plants that did establish persisted during favourable seasons at higher altitudes. Herbage yields of woolly pod vetch (Vicia dasycarpa cv. Namoi) and rose clover (T. hirtum cv. Hykon) occasionally exceeded yield of subterranean clover at some lower altitude sites, but those species failed to persist at other sites where grazing management may have been unsuitable. Barrel medic (Medicago truncatula) established satisfactorily but did not persist on the more acidic soils (pH <6.0). Both drilling and broadcasting establishment techniques produced satisfactory legume stands. Legume plant density was generally greater on heavier soils of basaltic origin than on lighter soils of rhyolitic origin.

Download Full-text

Anthropic expansion of Paraty in Serra da Bocaina National Park, Mata Atlântica Biome

Ambiente & sociedade ◽

10.1590/1809-4422asoc20200023r1vu2021l2ao ◽

2021 ◽

Vol 24 ◽

Author(s):

Camila Coelho Welerson ◽

Winne Nayadini Barão ◽

Brunna Araújo Quireli ◽

Vanêssa Lopes de Faria ◽

Nívea Adriana Dias Pons ◽

...

Keyword(s):

Land Use ◽

Vegetation Cover ◽

National Park ◽

Management Plan ◽

Park Management ◽

Native Vegetation ◽

Landsat 8 ◽

Master Plan ◽

Municipal Planning ◽

Management Plans

Abstract This paper analyzed the anthropic expansion of the municipality of Paraty-RJ in relation to the Serra da Bocaina National Park. In addition to the bibliographic and documentary revision of the Municipal Master Plan and the Park Management Plan, geoprocessing tools were used for chronological analyzes of land use and occupation change in 2001, 2006 and 2018, using images from the satellite Landsat 5 and Landsat 8. It was verified the growth of the anthropic occupation in a diffuse way in relation to the Park, without respect to the municipal planning, reflecting in the decrease of the native vegetation cover. Both the Master and Management Plans have been inefficient in terms of their objectives, justifying the need for improvements in Paraty and Park management through the responsible agencies.

Download Full-text

Analysis of vegetation dynamics using the normalized difference vegetation index (NDVI) at the archipelago of Fernando de Noronha, Pernambuco, Brazil

Interações (Campo Grande) ◽

10.20435/inter.v21i4.2432 ◽

2020 ◽

pp. 885-901

Author(s):

Kardelan Arteiro da Silva ◽

Soraya Giovanetti El-Deir ◽

José Jorge Monteiro Júnior ◽

João Paulo de Oliveira Santos ◽

Emanuel Araújo Silva

Keyword(s):

State Government ◽

Vegetation Cover ◽

Vegetation Index ◽

Normalized Difference Vegetation Index ◽

Management Plan ◽

Landsat 8 ◽

Conservation Policies ◽

Management Plans ◽

Landsat 7 ◽

Fernando De Noronha

Island environments have specific biotic and abiotic characteristics, as fragility, limitation of natural resources, geographic isolation, and fragmentation are determining factors that directly affect these areas. Thus, it is relevant to understand the natural evolution of the landscape in the islands, considering the anthropic actions and climate changes in the transformation of vegetation cover, as a means of time series and study of satellite images. This paper aims to analyze the dynamics of the landscape (changes in vegetation cover) of the Fernando de Noronha Archipelago concerning urban development, and other anthropic activities that occurred between 1999 and 2018, through remote sensing images, to establish comparisons with the Island Management Plans that were elaborated in the years of 2005 and 2017. Also, this study intends to raise elements to assist in the spatial management of the Archipelago and to establish Public Conservation Policies for Fernando de Noronha and other island areas. Images from Landsat 7 and Landsat 8 were obtained for scenes from 1999 and 2017, respectively. These images were preprocessed and analyzed in Quantum GIS 2.18 software. And applied the NDVI calculation. It was also used the database found in the sustainable management plan of the archipelago provided by the state government of Pernambuco. With these data, it was possible to diagnose a vegetative growth on the island of about 45.36% in 17 years corroborating with the changes found in the data coming from the island's management plan. However, there are no changes in the phytosociological diversity of the island, this cause is pointed out to the invading and ruderals species of the island that are established and propagate.

Download Full-text

The scientific background of competitive maize production

Acta Agraria Debreceniensis ◽

10.34101/actaagrar/150/1700 ◽

2018 ◽

pp. 33-46

Author(s):

János Nagy ◽

Adrienn Széles

Keyword(s):

Field Experiment ◽

Crop Production ◽

Plant Density ◽

Crop Protection ◽

Maize Yield ◽

Soil Conditions ◽

Maize Production ◽

Production Factors ◽

Term Field

The effect and interaction of crop production factors on maize yield has been examined for nearly 40 years at the Látókép Experiment Site of the University of Debrecen in a long-term field experiment that is unique and acknowledged in Europe. The research aim is to evaluate the effect of fertilisation, tillage, genotype, sowing, plant density, crop protection and irrigation. The analysis of the database of the examined period makes it possible to evaluate maize yield, as well as the effect of crop production factors and crop year, as well as the interaction between these factors. Based on the different tillage methods, it can be concluded that autumn ploughing provides the highest yield, but its effect significantly differed in irrigated and non-irrigated treatments. The periodical application of strip tillage is justified in areas with favourable soil conditions and free from compated layers (e.g. strip – strip – ploughing – loosening). Under conditions prone to drought, but especially in several consecutive years, a plant density of 70–80 thousand crops per hectare should be used in the case of favourable precipitation supply, but 60 thousand crops per hectare should not be exceeded in dry crop years. The yield increasing effect of fertilisation is significant both under non-irrigated and irrigated conditions, but it is much more moderate in the non-irrigated treatment. Selecting the optimum sowing date is of key importance from the aspect of maize yield, especially in dry crop years. Irrigation is not enough in itself without intensive nutrient management, since it may lead to yield decrease. The results of research, development and innovation, which are based on the performed long-term field experiment, contribute to the production technological methods which provide an opportunity to use sowing seeds, fertilisers and pesticides in a regionally tailored and differentiated way, adapted to the specific needs of the given plot, as well as to plan each operation and to implement precision maize production.

Download Full-text

Variation in seed yield and its components in the Australian native grass Microlaena stipoides as a guide to its potential as a perennial grain crop

Australian Journal of Agricultural Research ◽

10.1071/ar04204 ◽

2005 ◽

Vol 56 (3) ◽

pp. 309 ◽

Cited By ~ 12

Author(s):

C. L. Davies ◽

D. L. Waugh ◽

E. C. Lefroy

Keyword(s):

Seed Yield ◽

Seed Weight ◽

Seed Set ◽

Cropping Systems ◽

Spikelet Number ◽

Native Grass ◽

Plant Seed ◽

Grain Crop ◽

Microlaena Stipoides ◽

Perennial Grain

This research investigated the potential to domesticate an Australian native grass (Microlaena stipoides) to produce a perennial grain crop. Perennial grain crops offer a new solution to the long-standing problems of salinity and soil erosion associated with conventional cropping systems based on annual plants. Seed yield and its components (culm number, spikelet number per culm, seed set, seed weight) were measured in 46 accessions of Microlaena stipoides (microlaena, meadow or weeping rice grass) from Western Australia and New South Wales to quantify potentially useful variation in the species. A high degree of variability was found to exist, with a 20-fold range in seed yield (0.1–2.4 g/plant), 5-fold range in seed weight (129–666 mg per 100 seeds), 2-fold range in spikelet number (14–30 per culm), 8-fold range in seed set (12–98%), and a 5-fold range in culm number (11–59 per plant). Seed yield was positively and significantly (P < 0.05) correlated with culm number, seed set, and seed weight (r > 0.55 for all). No correlation was found between seed yield and spikelet number per culm (r = –0.14). The range in seed yield and its components suggests that there is sufficient variation within microlaena to make selections for higher yielding lines. This variation will enable breeders to exploit genetic diversity more efficiently and identify useful accessions for further work. High priority traits for future work include synchronous maturity and resistance to shattering.

Download Full-text