Field trials of transgenic crops may result in unintentional transgene flow to compatible crop, native, and weedy species. Hybridization outside crop fields may create novel forms with potential negative outcomes for wild and weedy plant populations. We report here the outcome of large outdoor mesocosm studies with canola (Brassica napus), transgenic canola, a sexually compatible weed B. rapa, ...

Cover crops are essential in agricultural management and especially in organic farming for protecting the soil from erosion, competing with weeds, preventing evaporative losses and improving soil quality and fertility. The choice of cover crop species is crucial in achieving the highest level of weed suppression and soil fertility enhancement. Cover crop systems with rye or mixtures of legumes ...

We investigated the effects of organic and conventional pest and fertility management on weed cover and the seed bank community in an organic rotation. The study was conducted during the 4th and 5th years of an organic rotation on part of a long term organic-conventional comparison trial. Results showed that although crop type (potato vs. cabbage) in a single year significantly affected wee...

abstract field experiment was conducted to evaluate the effects of sowing date, crop density, and weed interference on yield and yield components of chickpea in lorestan province during 2005-06. the experimental was a randomized complete block design by factorial arrangement with 4 replications. the experiment had 3 factors: sowing date at 2 levels (autumn, and winter), crop density at 3 levels...

Redroot pigweed is one of the injurious agricultural weeds on a worldwide basis. Understanding of its interference impact in crop field will provide useful information for weed control programs. The effects of redroot pigweed on cotton at densities of 0, 0.125, 0.25, 0.5, 1, 2, 4, and 8 plants m(-1) of row were evaluated in field experiments conducted in 2013 and 2014 at Institute of Cotton Res...

A general model of crop yield response to herbicide application is proposed. The model includes three components: the effect of herbicide dosage on weed density, the effect of surviving weed density on crop yield and the effect of herbicide directly on the crop. The model is used to estimate the response of wheat yield to application of diclofop-methyl to control ryegrass .(Lolium rigidum) in A...

crops that better tolerate weed competition or preempt resources from weeds may reduce dependence on herbicides and benefit an integrated weed management program. a field trail was conducted to determine the morphophysiological characteristics affecting tolerance and weed suppressive ability of some winter wheat cultivars in competition with rocket. the experimental treatments consisted of eigh...

Radiations and radioisotopes are used in agricultural research to induce genetic variability in crop plants to develop improved varieties, to manage insect pests, monitor fate and persistence of pesticides, to study fertilizer use efficiency and plant micronutrient uptake and also to preserve agricultural produce. Use of radiation and radioisotopes in agriculture is one of the most important fi...

BACKGROUND Arbuscular mycorrhizal fungi (AMF) are known for their beneficial effects on plants. However, there is increasing evidence that some ruderal plants, including several agricultural weeds, respond negatively to AMF colonization. Here, we investigated the effect of AMF on the growth of individual weed species and on weed-crop interactions. METHODOLOGY/PRINCIPAL FINDINGS First, under c...

Reducing herbicide use may result in residual weed flora arable fields, increasing crop–weed competition for resources. In temperate cropping systems, light and nitrogen are the main resources which plants compete. As increases, soil mineral might become less abundant as of fertiliser is reduced environmental reasons (pollutions biodiversity loss). Better understanding crops weeds competitive a...