The Experts below are selected from a list of 84 Experts worldwide ranked by ideXlab platform
D F Chapman - One of the best experts on this subject based on the ideXlab platform.
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ranunculus acris control in dairy pasture a comparison of herbicides plant growth promoters a bioherbicide and pregraze mowing
New Zealand Journal of Agricultural Research, 2019Co-Authors: Shona L Lamoureaux, Sarah Jackman, Alasdair Noble, D F ChapmanAbstract:The efficacy of control tactics for Ranunculus acris was quantified on poorly- and well-drained soils in a factorial experiment conducted over three years in 18 dairy pastures. Soil drainage, gibberellic acid and Nitrogenous Fertiliser (growth promoters), and a bioherbicide utilising Sclerotinia sclerotiorum had no effect on the cover of R. acris. The herbicides aminopyralid and aminopyralid+triclopyr, by contrast, gave long-lasting reductions in the cover of the weed and substantial temporary reductions in the clovers. Flumetsulam, thifensulfuron methyl, MCPA, MCPB and MCPB+bentazone were less effective overall. Pregraze mowing reduced R. acris as the frequency of mowing increased. For all herbicides, there was a 1:1 replacement of R. acris by grasses and clovers. The efficacy of the treatments varied greatly between pastures, possibly due to genetic differences between the R. acris populations and their historical exposure to the herbicides.
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Ranunculus acris control in dairy pasture – a comparison of herbicides, plant growth promoters, a bioherbicide and pregraze mowing
2018Co-Authors: Graeme W. Bourdôt, Shona L Lamoureaux, Sarah D. Jackman, Alasdair D. L. Noble, D F ChapmanAbstract:The efficacy of control tactics for Ranunculus acris was quantified on poorly- and well-drained soils in a factorial experiment conducted over three years in 18 dairy pastures. Soil drainage, gibberellic acid and Nitrogenous Fertiliser (growth promoters), and a bioherbicide utilising Sclerotinia sclerotiorum had no effect on the cover of R. acris. The herbicides aminopyralid and aminopyralid+triclopyr, by contrast, gave long-lasting reductions in the cover of the weed and substantial temporary reductions in the clovers. Flumetsulam, thifensulfuron methyl, MCPA, MCPB and MCPB+bentazone were less effective overall. Pregraze mowing reduced R. acris as the frequency of mowing increased. For all herbicides, there was a 1:1 replacement of R. acris by grasses and clovers. The efficacy of the treatments varied greatly between pastures, possibly due to genetic differences between the R. acris populations and their historical exposure to the herbicides.
Francesco Giunta - One of the best experts on this subject based on the ideXlab platform.
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the effect of Nitrogenous Fertiliser application on leaf traits in durum wheat in relation to grain yield and development
Field Crops Research, 2009Co-Authors: Simonetta Fois, Rosella Motzo, Francesco GiuntaAbstract:Nitrogen (N) fertilisation boosts the grain yield of wheat through its influence on yield components, phenology and leaf traits. Both crop growth and senescence are dependent on N supply, as are the number of kernels set per unit area and per ear, and the mean kernel size. A two-season trial of four semi-dwarf durum wheat cultivars, grown at two levels of N, was used to illustrate the effects of N on canopy temperature, leaf resistance and flag leaf senescence pattern under irrigated conditions in a Mediterranean climate, and to explore the consequences of these effects on the crop phenology, its yield and its yield components. The well-fertilised crop developed a larger leaf area index at anthesis and a lower leaf resistance, thus generating a lower canopy temperature and delayed anthesis. Its grain fill duration was shorter, in spite of its lower canopy temperature, presumably because the increased N availability resulted in the development of a stronger sink (more kernels per unit area and per ear), which was associated with earlier senescence, thereby shortening the duration of grain fill, and led to reduced kernel weight.
Shona L Lamoureaux - One of the best experts on this subject based on the ideXlab platform.
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ranunculus acris control in dairy pasture a comparison of herbicides plant growth promoters a bioherbicide and pregraze mowing
New Zealand Journal of Agricultural Research, 2019Co-Authors: Shona L Lamoureaux, Sarah Jackman, Alasdair Noble, D F ChapmanAbstract:The efficacy of control tactics for Ranunculus acris was quantified on poorly- and well-drained soils in a factorial experiment conducted over three years in 18 dairy pastures. Soil drainage, gibberellic acid and Nitrogenous Fertiliser (growth promoters), and a bioherbicide utilising Sclerotinia sclerotiorum had no effect on the cover of R. acris. The herbicides aminopyralid and aminopyralid+triclopyr, by contrast, gave long-lasting reductions in the cover of the weed and substantial temporary reductions in the clovers. Flumetsulam, thifensulfuron methyl, MCPA, MCPB and MCPB+bentazone were less effective overall. Pregraze mowing reduced R. acris as the frequency of mowing increased. For all herbicides, there was a 1:1 replacement of R. acris by grasses and clovers. The efficacy of the treatments varied greatly between pastures, possibly due to genetic differences between the R. acris populations and their historical exposure to the herbicides.
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Ranunculus acris control in dairy pasture – a comparison of herbicides, plant growth promoters, a bioherbicide and pregraze mowing
2018Co-Authors: Graeme W. Bourdôt, Shona L Lamoureaux, Sarah D. Jackman, Alasdair D. L. Noble, D F ChapmanAbstract:The efficacy of control tactics for Ranunculus acris was quantified on poorly- and well-drained soils in a factorial experiment conducted over three years in 18 dairy pastures. Soil drainage, gibberellic acid and Nitrogenous Fertiliser (growth promoters), and a bioherbicide utilising Sclerotinia sclerotiorum had no effect on the cover of R. acris. The herbicides aminopyralid and aminopyralid+triclopyr, by contrast, gave long-lasting reductions in the cover of the weed and substantial temporary reductions in the clovers. Flumetsulam, thifensulfuron methyl, MCPA, MCPB and MCPB+bentazone were less effective overall. Pregraze mowing reduced R. acris as the frequency of mowing increased. For all herbicides, there was a 1:1 replacement of R. acris by grasses and clovers. The efficacy of the treatments varied greatly between pastures, possibly due to genetic differences between the R. acris populations and their historical exposure to the herbicides.
Takeshi Watanabe - One of the best experts on this subject based on the ideXlab platform.
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efficient rates of Nitrogenous Fertiliser for irrigated sweet sorghum cultivation during the post rainy season in the semi arid tropics
European Journal of Agronomy, 2015Co-Authors: Tomohiro Kurai, Shamitha R Morey, S P Wani, Takeshi WatanabeAbstract:Sorghum (Sorghum bicolor (L.) Moench) is a multipurpose crop with high tolerance to environmental stresses. To meet the increased demand for food and biofuel, current agricultural practices rely on the excessive use of inorganic nitrogen (N) Fertiliser. However, excessive N Fertiliser has resulted in negative environmental effects. In view of the varied N use efficiency (NUE) of plants under different environmental conditions, the aim of this study was to evaluate the efficient rates of N Fertiliser in semi-arid tropics for sweet sorghum cultivation during post-rainy season by maximising NUE without compromising yield. Field experiments were conducted on two sweet sorghum cultivars with four different N fertilisation rates (0, 63, 90 and 150 kg N ha−1) during the post-rainy season in India. Grain and stalk yields increased with N Fertiliser, but significantly only up to 90 kg N ha−1. The observed increases in grain yield were attributed by increases in kernel numbers. Corresponding with the differences in biomass, both relative growth rate (RGR) and crop growth rate (CGR) increased with N fertilisation rate up to 90 kg N ha−1. Component analyses of RGR and CGR revealed that both net assimilation rate (NAR) and leaf area index (LAI) significantly contributed with increasing rates of N Fertiliser applications. Furthermore, studies of NUE indices showed that agronomic N use efficiency (ANUE, indicating yield production per unit of Fertiliser N) responded comparably up to 90 kg N ha−1, and decreased significantly thereafter. Analysis of ANUE components showed that the decline in ANUE at 150 kg N ha−1 was due to a decrease in physiological N use efficiency (PNUE), indicating that the absorbed N was not utilised efficiently for biomass and yield production, but merely accumulated. These results together suggest that 90 kg N ha−1 is an efficient N fertilisation rate suggested among the tested treatments for sustainable sweet sorghum cultivation during the post-rainy season in the semi-arid tropics.
Hendrikus J Laanbroek - One of the best experts on this subject based on the ideXlab platform.
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nitrogen as a regulatory factor of methane oxidation in soils and sediments
FEMS Microbiology Ecology, 2004Co-Authors: Paul L E Bodelier, Hendrikus J LaanbroekAbstract:The oxidation of methane by methane-oxidising microorganisms is an important link in the global methane budget. Oxic soils are a net sink while wetland soils are a net source of atmospheric methane. It has generally been accepted that the consumption of methane in upland as well as lowland systems is inhibited by Nitrogenous Fertiliser additions. Hence, mineral nitrogen (i.e. ammonium/nitrate) has conceptually been treated as a component with the potential to enhance emission of methane from soils and sediments to the atmosphere, and results from numerous studies have been interpreted as such. Recently, ammonium-based fertilisation was demonstrated to stimulate methane consumption in rice paddies. Growth and activity of methane-consuming bacteria in microcosms as well as in natural rice paddies was N limited. Analysing the available literature revealed that indications for N limitation of methane consumption have been reported in a variety of lowland soils, upland soils, and sediments. Obviously, depriving methane-oxidising bacteria of a suitable source of N hampers their growth and activity. However, an almost instantaneous link between the presence of mineral nitrogen (i.e. ammonium, nitrate) and methane-oxidising activity, as found in rice soils and culture experiments, requires an alternative explanation. We propose that switching from mineral N assimilation to the fixation of molecular nitrogen may explain this phenomenon. However, there is as yet no experimental evidence for any mechanism of instantaneous stimulation, since most studies have assumed that Nitrogenous Fertiliser is inhibitory of methane oxidation in soils and have focused only on this aspect. Nitrogen as essential factor on the sink side of the global methane budget has been neglected, leading to erroneous interpretation of methane emission dynamics, especially from wetland environments. The purpose of this minireview is to summarise and balance the data on the regulatory role of nitrogen in the consumption of methane by soils and sediments, and thereby stimulate the scientific community to embark on experiments to close the existing gap in knowledge.