Effect of weed competition periods on weeds and yield of black seed was studied through field experiments conducted at Agronomic Research Area, University of Agriculture, Faisalabad during winter 2006-07 and 2007-08. Weeds were allowed to compete with the crop for 40, 50, 60, 70, 80 days after sowing and throughout the growth season along with a weed free treatment. The data on weed density and...

Rubber tree production is reduced by weeds that compete for environmental resources; therefore, the timing and duration of weed control influences weed interference. The objectives of this study were to evaluate the growth of rubber tree (Hevea brasiliensis) plants, to determine the critical period for weed control, and to evaluate the growth recovery of rubber trees that coexisted with weeds f...

Bentazon, C 0 2-Assimilation, Inhibition of Photosynthesis, Photosystem 2-Herbicide, Shade-Type Adaptation of Chloroplasts The inhibition of photosynthetic C 0 2-assimilation and of the variable chlorophyll fluorescence as well as uptake and transport of 14C-labelled bentazon and the possibilities for a herbicideinduced shade-type modification of the photosynthetic apparatus were investigated i...

In 2008, agricultural producers planted more than 80% of US cotton and corn acreage and more than 90% of soybean acreage to transgenic glyphosate-tolerant, Roundup Ready® (RR) seed varieties (US Department of Agriculture Agricultural Marketing Service [USDA AMS], 2008; USDA National Agricultural Statistics Service [NASS], 2008). Many studies report significant pecuniary and non-pecuniary benefi...

To study synanthropic plants (weeds), weeds need to be separated from non-weeds, a difficult task due the existing gradient in nature. A representative family of Mexican flora (Asteraceae) and state very rich species (Michoacán) are used as model for this additional analyses. total 357 listed based on critical review specimens bibliographic information, well defined criteria. In addition, tribe...

field experiments were conducted in zanjan, markazi, esfahan, and chaharmahal va bakhtiari provinces to evaluate imazetapyr herbicide efficiency for weed control in common bean (phaseolus vulgaris l.) in 2006. there were four replications at each site and treatments were arranged in a randomized complete block design. in zanjan, maximum weed biomass reduction by 91 and 88 percent were achieved ...

abstract in this study, willingness to pay of 180 wheat farmers in khorasan razavi province to remove weeds in different options and different growth stages in 2008 through logarithmic regression was investigated. the results indicated that farmer's total annual income, being perennial of weeds and dummy variables percent of removing weeds in growth different stages, had positive and significan...

4-Sulfenyl-2-carbamoyl-4-isoxazolin-3-ones (4) were designed on the basis of biological isosterism and prepared in four steps. Some of these compounds showed sufficient pre-emergent herbicidal activities against various kinds of weeds. Among the synthesized compounds, 2-(N-(4-chlorophenyl)-N-isopropylcarbamoyl)-4-ethylthio-5-methyl-4 -isoxazolin-3-one (4cd) exhibited the most promising activity.

The Hindu Vedas place teachers on a high pedestal: “a guru creates and sustains knowledge, and destroys the weeds of ignorance, just like the creator, the sustainer, and the destroyer of this universe”. It is no surprise then that students see teachers as authority figures that teach them the truth. Thus, the teacher has a profound responsibility to guide students by helping them to assimilate ...

Although cheatgrass (Bromus tectorum) has been widely distributed across western rangelands for >70 years, the full ecologic and economic impacts of this non-native invasive plant have not yet occurred. Unfortunately, several independent lines of evidence indicate that the rate at which acreage becomes infested with cheatgrass is increasing rapidly. Furthermore, the invasion and spread of a num...