Several studies have expressed concerns about the effects of gene flow from transgenic herbicide-resistant crops to their wild relatives, but no major problems have been observed. This review describes a case study in which what has been feared in transgenics regarding gene flow has actually changed biodiversity and people's lives. Nontransgenic imidazolinone-resistant rice (IMI-rice) cultivars...

Reniform nematode (Rotylenchulus reniformis) resistance is being transferred to Gossypium hirsutum from its distant relatives. Reports of fluometuron damage to LONREN lines with nematode resistance from G. longicalyx raised concerns about introducing herbicide sensitivity from other nematode resistance sources. The research objective was to evaluate 15 sources of reniform nematode resistance fo...

The advent of biotechnology-derived, herbicide-resistant crops has revolutionized farming practices in many countries. Facile, highly effective, environmentally sound, and profitable weed control methods have been rapidly adopted by crop producers who value the benefits associated with biotechnology-derived weed management traits. But a rapid rise in the populations of several troublesome weeds...

Genetic modification of crop plants has promoted concerns about potential environmental effects of this new technology. In this essay, I will discuss the environmental effects of genetic modification of crop plants using herbicide resistance as an example. Considering herbicide resistance as an old agricultural trait, it is difficult to find any reason to assess the environmental risks of genet...

The rapid evolution of herbicide resistance poses a significant threat for conventional agricultural practices. In practice, herbicide resistance seems to be a very complicated problem to deal with. Extension can play a significant role in managing herbicide resistance educating farmers on the main advantages and disadvantages of the available methods aiming to control and minimize herbicide re...

Since the beginning of agriculture, crops have been exposed to recurrent invasion by weeds that can impose severe reductions in crop quality and yield. There have been continuing efforts to reduce the impacts of weeds on production. More than 40 yr ago, overreliance on herbicide technology to reduce weed infestations resulted in the selection of adaptive traits that enabled weed survival and re...

The herbicide norflurazon inhibits carotene biosynthesis in photosynthetic organisms by blocking the enzyme phytoene dehydrogenase (= phytoene desaturase). We have isolated norflurazon-resistant mutants of the cyanobacterium Synechococcus PCC7942. The herbicide-resistance gene from the mutant NFZ4 has been cloned by genetic complementation of the resistance trait in wild type cells. The experim...

Resistance to herbicides in arable weeds is increasing rapidly worldwide and threatening global food security. Resistance has now been reported to all major herbicide modes of action despite the development of resistance management strategies in the 1990s. We review here recent advances in understanding the genetic bases and evolutionary drivers of herbicide resistance that highlight the comple...

H erbicide resistance is the inherited ability of a plant to survive and reproduce following exposure to a dose of herbicide that would normally be lethal to the wild type. In a plant, resistance may occur naturally due to selection or it may be induced through such techniques as genetic engineering. Resistance may occur in plants as the result of random and infrequent mutations; there has been...

Herbicide-resistant Palmer amaranth is a widespread issue in row-crop production in the Midsouthern US. Palmer amaranth is commonly found on roadside habitats in this region, but little is known on the degree of herbicide resistance in these populations. Herbicide resistance in roadside Palmer amaranth populations can represent the spread of an adaptive trait across a selective landscape. A lar...