Search results for "weed"

Herbicidal activity of essential oils extracted from different Mediterranean species against Echinochloa crus galli

Weed infestation in agricultural fields can cause huge economic losses and low-quality crop yields. Echinochloa crus-galli (L.) P.Beauv. (barnyardgrass) is one of the greatest yields limiting weeds in rice cultivation systems. It is a cosmopolitan weed in both temperate and tropical regions and is reported as a weed in 36 different crops in 61 countries. The success of this weed may be attributed to the production of large numbers of small, easily dispersed seeds per plant, possession of seed dormancy, rapid development and ability to flower under a wide range of photoperiods, and relative resistance of mature plants to herbicide sprays. Thus, the best way to control barnyardgrass in an env…

Modélisation d'images agronomiques - application a la reconnaissance d'adventices par imagerie pour une pulvérisation localisée

2009

Plant (crop and weed) identification is a very active field of research in agriculture since the reinforcement of European laws about pesticide applications for a site-specific management of spraying practices. A new crop/weed simulation model was developed to allow the evaluation of crop/weed spatial identification methods from imaging. Considering multiples agronomic parameters – crop location, weed infestation rate, weed spatial distribution – the first step of this model allows the simulation of an infested crop field. Then, in a second step, a world to camera transformation is applied to allow every kind of picture (with or without perspective effect). The validation of this model was …

Ex ante evaluation of cropping systems for weed-mediated pests and environmental benefits with simulation–based indicators

2016

SPEEAGESTADAGROSUP; International audience; Integrated crop protection tolerates residual weed floras if they are not harmful for crop production. These weeds can host harmful crop pests, among which parasitic plants such as broomrape (Phelipanche ramosa). They can also contribute to reduce soil erosion as well as nitrate and pesticide leaching. To evaluate these weed impacts of management practices ex ante, we developed indicators for the weed dynamics model FLORSYS (Colbach et al., 2014) and then used the model to predict weed-mediated broomrape risk and environmental benefits in cropping systems from five French regions. Materials and Methods FLORSYS is a virtual field on which cropping …

Sustainable Weed, Disease and Pest Management in Medicinal and Aromatic Plants

2015

As for all other crops, in MAPs as well, weeds, diseases and pests are important yield-reducing factors, which may severely curtain biomass production and, that is maybe more important, may affect several qualitative aspects of production. Research about this topic is generally lacking, for two main reasons: the first is that MAPs are generally grown on rather limited areas, and the incidence of specific pests and diseases rarely takes a relevance outside rather narrow boundaries. The second reason is that the economical importance of MAPs is much lower than that ascribed to the “major” crops, which the bigger efforts of research are addressed to. In the changing scenario of latter years, h…

Analysis of impaired in vitro immunoglobulin synthesis in rheumatoid arthritis.

1990

Decreased immunoglobulin production in pokeweed mitogen driven lymphocyte cultures has been reported in rheumatoid arthritis (RA). Here various activators and experimental designs have been used to determine the contribution of B cells, T cells, or monocytes to this low response. Sixty patients with RA and paired controls were studied at the onset of disease and again six months later. Concentrations of IgA, IgG, and IgM in cultures of RA peripheral blood mononuclear cells stimulated with thymus dependent activators were already decreased at the onset of the disease. Six months later RA mononuclear cells produced even lower concentrations of immunoglobulin. In contrast, stimulation with a T…

Effect of Wheat Straw as a Cover Crop on the Chlorophyll, Seed, and Oilseed Yield of Trigonella foeunm graecum L under Water Deficiency and Weed Comp…

2019

The effects of water stress on fenugreek crops are well documented. However, little is known about how these plants respond to water deficits under a soil-mulching system when the surface is protected. Therefore, the current research aims to demonstrate the possibility of reducing the impact of water stress and weed competition on the fenugreek crop through the use of wheat residues as a cover crop on the soil surface. A field experiment was carried out during the winter season (2016&ndash

A chemometric approach to evaluate the impact of pulses, Chlorella and Spirulina on proximate composition, amino acid, and physicochemical properties…

2019

Changes in physicochemical parameters, proximate composition, amino acid and taste profiles of turkey burgers enriched at 1% with soy (control), pulses, Chlorella and Spirulina proteins were studied. Results: Color parameters, pH, ash content, total, essential and non-essential amino acids were significantly different among the different type of turkey burgers prepared. In this regard, turkey burgers made with pea protein presented the highest values for pH and lightness, whereas the samples prepared with broad bean showed the highest redness. The inclusion of bean and seaweed produced a marked increase of glutamic acid, lysine and aspartic acid. However, the taste profile was similar in th…

COMPLEMENT-DEPENDENT B-CELL ACTIVATION BY COBRA VENOM FACTOR AND OTHER MITOGENS?

1974

It has been proposed that two distinct signals are required for the triggering of the precursors of antibody-forming bone marrow-derived cells (B cells): (a) the binding of antigen or of a mitogen to the corresponding receptor sites on B-cell membranes and (b) the interaction of activated C3 with the C3 receptor of B lymphocytes. There is growing evidence that B-cell mitogens and T (thymus-derived cell)-independent antigens are capable of activating the alternate pathway of the complement system (bypass). Therefore, the effect of another potent bypass inducer was investigated with regard to B-cell activation and the role of C3. Purified, pyrogen-free cobra venom factor was mitogenic for bot…

Antioxidant potential of Himanthalia elongata for protection against ischemia-reperfusion injury in the small bowel

2016

Seaweed has been associated with the prevention and/or treatment of various diseases related to oxidative stress because of its antioxidant activity. We investigated the protective potential of extract of Himanthalia elongata against ischemia-reperfusion (I/R) injury in the intestine of rats.Seventy-two (72) male Wistar albino rats were randomly assigned into 12 groups as follows: sham, I/R only, I/R plus vehicle at 3 time points, and I/R plus extract at 3 time points. The degree of intestinal injury was determined by oxidative stress using lipid peroxidation, superoxide dismutase, catalase, and glutathione peroxidase after mesenteric ischemia-reperfusion. A histological study was also perf…

The invasive seaweed Asparagopsis taxiformis erodes the habitat structure and biodiversity of native algal forests in the Mediterranean Sea

2021

Abstract Invasive seaweeds are listed among the most relevant threats to marine ecosystems worldwide. Biodiversity hotspots, such as the Mediterranean Sea, are facing multiple invasions and are expected to be severely affected by the introduction of new non-native seaweeds in the near future. In this study, we evaluated the consequences of the shift from the native Ericaria brachycarpa to the invasive Asparagopsis taxiformis habitat on the shallow rocky shores of Favignana Island (Egadi Islands, MPA, Sicily, Italy). We compared algal biomass and species composition and structure of the associated epifaunal assemblages in homogenous and mixed stands of E. brachycarpa and A. taxiformis. The r…