Friday, July 31, 2009
How weed killers might protect our eyes
Farmers — and the rest of us — often employ modern chemistry to protect our botanical babies from bullying weeds. And while our crops and ornamentals may benefit, weeds have always been the real target of the herbicides that we apply. But that may change.
A new study finds that at least one herbicide, when applied directly onto young sweet corn plants, can boost the pigment content of the kernels that mature a month or more later. Dietary sources of those pigments appear to play a critical role in helping the human eye stay healthy.
The newly observed corn effect is highly selective, says Dean Kopsell of the University of Tennessee, in Knoxville. It’s also far from what this vegetable crop physiologist had expected when his team began its experiments.
The herbicide they’ve been studying — mesotrione — works by mucking up the leafy machinery by which plants produce a family of important chemicals known as carotenoids. They’re best known as the plant pigments responsible for making carrots orange and watermelons red. But they’re produced in almost all plants, even those that are simply green.
Carotenoids can serve as solar collectors, Kopsell notes, harvesting light just as chlorophyll does (but from a range of wavelengths chlorophyll doesn’t handle effectively or at all). Carotenoids also help dissipate heat so that sunlight doesn’t fry tender plants. Bottom line: In broad-leaf weeds, mesotrione will bleach the greenery and eventually kill the plant.
Through this article,i learnt that large and growing body of evidence indicates that these carotenoids play an important role in the human eye by absorbing blue light. Without sufficient concentrations of lutein and zeaxanthin in the retina’s macula, this region of the eye may become damaged. Indeed, a review of the literature by scientists at Tufts University and the Agriculture Department’s Jean Mayer Human Nutrition Research Center on Aging (both in Boston) found “ample evidence” that the lower the concentration of these carotenoids in the macula, the higher an individual’s risk “of age-related macular degeneration, an irreversible process that is the major cause of blindness in the elderly.”
Hitomi 3 Unity ¶ 7:40 PM
A new study finds that at least one herbicide, when applied directly onto young sweet corn plants, can boost the pigment content of the kernels that mature a month or more later. Dietary sources of those pigments appear to play a critical role in helping the human eye stay healthy.
The newly observed corn effect is highly selective, says Dean Kopsell of the University of Tennessee, in Knoxville. It’s also far from what this vegetable crop physiologist had expected when his team began its experiments.
The herbicide they’ve been studying — mesotrione — works by mucking up the leafy machinery by which plants produce a family of important chemicals known as carotenoids. They’re best known as the plant pigments responsible for making carrots orange and watermelons red. But they’re produced in almost all plants, even those that are simply green.
Carotenoids can serve as solar collectors, Kopsell notes, harvesting light just as chlorophyll does (but from a range of wavelengths chlorophyll doesn’t handle effectively or at all). Carotenoids also help dissipate heat so that sunlight doesn’t fry tender plants. Bottom line: In broad-leaf weeds, mesotrione will bleach the greenery and eventually kill the plant.
Through this article,i learnt that large and growing body of evidence indicates that these carotenoids play an important role in the human eye by absorbing blue light. Without sufficient concentrations of lutein and zeaxanthin in the retina’s macula, this region of the eye may become damaged. Indeed, a review of the literature by scientists at Tufts University and the Agriculture Department’s Jean Mayer Human Nutrition Research Center on Aging (both in Boston) found “ample evidence” that the lower the concentration of these carotenoids in the macula, the higher an individual’s risk “of age-related macular degeneration, an irreversible process that is the major cause of blindness in the elderly.”
Hitomi 3 Unity ¶ 7:40 PM
Post a Comment