chlorophyll fluorescence induction is a rapid and noninvasive technique for measuring photosynthetic electron transport in plants. chlorophyll fluorescence measurements were performed under greenhouse condition to characterize how the fluorescence induction curves (kautsky curve) and its parameters were affected by metribuzin in susceptible and resistant junglerice (echinochloa colona (l.) link...

1. Invasive species are one of the leading threats to biodiversity worldwide. Therefore, chemical herbicides are increasingly used to control invasive plants in natural and semi-natural areas. Little is known about the non-target impacts of these chemicals on native species. 2. We conducted an experiment to test the demographic effects of the herbicide picloram on a native dominant forb, arrowl...

to study the effects of urea foliar spray at different plant growth stages on grain yield and protein percentage of two dryland wheat varieties of sardari and azar 2, an experiment was conducted in east mangor agricultural station of mahabad in 2007– 2008. the experiment design was split plot based on randomized complete block design with three replications. treatments were 50 gr×10 m-2 n as ur...

management of a companion crop is critical to successful establishment of perennial forages (Albrecht and Hall, Weed control during alfalfa (Medicago sativa L.) establishment is 1995). a primary concern of forage producers. Companion crops and clearWeed management is important for decreasing comseeding with an herbicide are commonly used methods for establishing alfalfa. This study evaluated an...

Herbicides may damage soybean in conventional production systems. Chlorophyll fluorescence imaging technology has been applied to identify herbicide stress in weed species a few days after application. In this study, greenhouse experiments followed by field experiments at five sites were conducted to investigate if the chlorophyll fluorescence imaging is capable of identifying herbicide stress ...

Background: The herbicide RoundUp® became widely used in agriculture in the mid-1990s. Current populations of the crop weed Ipomoea purpurea exhibit both resistance and tolerance to RoundUp, which are two types of defence that have previously been shown to have a genetic basis in this weed species. Questions: Did the genetic basis of RoundUp defence antedate the introduction of RoundUp? If so, ...

Palmer amaranth, a dioecious summer annual species, is one of the most trouble‐ some weeds in the agronomic crop production systems in the United States. In the last two decades, continuous reliance on herbicide(s) with the same mode of action as the sole weed management strategy has resulted in the evolution of herbicideresistant (HR) weeds, including Palmer amaranth. By 2015, Palmer amaranth ...

ABSTRACT-Several herbicides are registered for selective weed control in sugar beet; however, no single chemical herbicide can control all weeds in beet fields. Frequently, two or more herbicides may have to be combined sequentially or as tank mixed to achieve adequate broad-spectrum weed control. In order to evaluate the effects of some combinations of broadleaf herbicides on sugar beet yield ...

SUMMARY Simazine loss from soil to surface runoff water produce both a decrease in the effectiveness of the soil chemical treatment and a water quality hazard in receiving waters. Simazine has been found in 30% of wells sampled in Fresno and Tulare counties, California and some contamination has been attributed to simazine use in citrus orchards. Contamination of receiving water from herbicides...