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As clever as fertilizer…
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is believed to be ubiquitous in plant cells, and work by Christine Gietl and colleagues [Proc. Natl. Acad. Sci. U. S. A. (2001) 98, 5353–5358; Naturwissenschaften (2001) 88, 49–58] implicates the organelle in programmed cell death (PCD). Ricinosomes store large amounts of inactive cysteine endopeptidases, which are processed to the active form upon release from the organelle during late stages of PCD, and appear to have roles in many degradative activities associated with senescence. NC
UN protects crop diversity At the beginning of July, the UN reached a landmark agreement to protect and promote the seed banks that hold the world’s diversity of agricultural crops. Under the agreement, plant breeders and geneticists developing new crop varieties must make mandatory payments for access to public seed banks. The pact promotes the need for farmers to keep and sell farmsaved seed. Representatives of 161 countries reached a consensus agreement at the UN Food and Agriculture Organization’s headquarters in Rome (Italy). Officials did not include issues related to seed patenting in the current agreement. [Brough, D. (2001) Toronto Star 2 July, D06 (Business section)] TS
The true spider plant In the UK, the house-plant Chlorophytum elatum is commonly known as the spider plant. However, it seems that the name is more appropriate to certain tobacco and potato plants that have been engineered to make spider silk proteins (‘spidroins’). Because of its remarkable lightness, strength and recyclability, spider silk could replace plastic for many uses. Unfortunately, spiders don’t make enough of it to satisfy the demands of industry. Using genetically engineered members of the Solanaceae, Jürgen Scheller and co-workers [Nat. Biotechnol. (2001) 19, 573–577] have generated plants that appear normal but with spidroins accounting for up to 2% of total soluble protein. NC
Salvia-tion or curse? Health care and legal officials in the USA have growing concern over the use of a legal shamanist drug. Salvia divinorum, http://plants.trends.com
TRENDS in Plant Science Vol.6 No.9 September 2001
commonly known as ska Maria Pastora or diviner’s sage, is a potent hallucinogenic herb that is currently legal in the USA. The plant is native to Mexico and was imported into the USA in the early 1960s. Scientists identified Salvinorum A as the active chemical that causes the hallucinogens. But neurologist Ethan Russo (MT, USA) warns that ‘we don’t know how [Salvia] works. It doesn’t work on serotonin, dopamine or any of the known neurotransmitters.’ Users claim the drug is non-addictive, but its long-term effects are not known. (Deutsche Presse-Agentur 9 July 2001) TS
Keeping photosynthesis in the dark When is an obligate photoautotroph not an obligate photoautotroph? When you genetically engineer it otherwise. Kirk Apt and colleagues have introduced a gene for a human glucose transporter into the marine diatom Phaeodactylum tricornutum [Science (2001) 292, 2073–2075] and converted it from a photosynthetic organism to one that could survive for many days in the dark, fuelled only by exogenously supplied glucose. The work is seen as a major breakthrough in the use of fermentation technology for the commercial exploitation of algae because it reduces previous limitations associated with their lightdependent growth. NC
Transforming iron uptake by rice Nutrient availability severely limits plant growth in many areas of the world. Low levels of nutrient can usually be overcome by adding fertiliser to the crop. Where the problem is due to the plant’s inability to take up sufficient nutrient, genetic engineering can help. Using genetic engineering, Michiko Takahashi and co-workers have created rice plants harboring nicotianamine aminotransferase genes from barley [Nat. Biotechnol. (2001) 19, 466–479]. The genes encode enzymes involved in the production of siderophores, natural iron-chelators secreted by many crop plants, which solubilize iron and enhance its uptake from alkaline soils. Siderophore production in unmodified rice is low, which compromises its ability to grow on alkaline soil. NC
405
No cotton-pickin’ blues? India provides >15% of the world’s cotton. Almost 40% of pesticides used in India are directed at bollworm, which can ravage cotton crops. Cotton genetically modified with Cotton bollworm. Courtesy of Scott Bauer, USDA. the Bt (Bacillus thuringiensis) toxin to combat bollworm has been approved by scientists at India’s Dept of Biotechnology. In spite of the strength of the economic argument in its favor, India’s Environment Dept has recently halted the commercial use of such GM cotton. Notwithstanding extensive trials of the plants, it seems that worldwide ‘the jury is still out’ on the wisdom or otherwise of using this technology. [Nature (2001) 411, 983] NC
As clever as fertilizer... Although it is often essential that we add fertilizer to enhance crop growth, much of that runs off the soil and ends up in rivers rather than in the growing plants. Not only is this an expensive waste, it harms the environment and endangers human health. To avoid these problems, scientists at Penn State University (USA) have developed a system that releases only as much fertilizer as is needed for the plant’s growth requirements. Although currently only available for phosphorus, in trials the ‘smart’ fertilizer improved plant growth and drought tolerance, and prevented up to 90% of the nutrient run-off associated with conventional fertilizers. Similar systems for nitrogen and potassium are planned. (http://www.psu.edu/ur/2001/smartfertilizer. html) NC
From seedy to CD, Linneaus’ herbarium on disk Identification of new plant species often requires reference to herbarium specimens to ensure novelty and to help determine evolutionary relationships between the new and the already known. Unfortunately, in many cases the
1360-1385/01/$ – see front matter © 2001 Elsevier Science Ltd. All rights reserved.
is believed to be ubiquitous in plant cells, and work by Christine Gietl and colleagues [Proc. Natl. Acad. Sci. U. S. A. (2001) 98, 5353–5358; Naturwissenschaften (2001) 88, 49–58] implicates the organelle in programmed cell death (PCD). Ricinosomes store large amounts of inactive cysteine endopeptidases, which are processed to the active form upon release from the organelle during late stages of PCD, and appear to have roles in many degradative activities associated with senescence. NC
UN protects crop diversity At the beginning of July, the UN reached a landmark agreement to protect and promote the seed banks that hold the world’s diversity of agricultural crops. Under the agreement, plant breeders and geneticists developing new crop varieties must make mandatory payments for access to public seed banks. The pact promotes the need for farmers to keep and sell farmsaved seed. Representatives of 161 countries reached a consensus agreement at the UN Food and Agriculture Organization’s headquarters in Rome (Italy). Officials did not include issues related to seed patenting in the current agreement. [Brough, D. (2001) Toronto Star 2 July, D06 (Business section)] TS
The true spider plant In the UK, the house-plant Chlorophytum elatum is commonly known as the spider plant. However, it seems that the name is more appropriate to certain tobacco and potato plants that have been engineered to make spider silk proteins (‘spidroins’). Because of its remarkable lightness, strength and recyclability, spider silk could replace plastic for many uses. Unfortunately, spiders don’t make enough of it to satisfy the demands of industry. Using genetically engineered members of the Solanaceae, Jürgen Scheller and co-workers [Nat. Biotechnol. (2001) 19, 573–577] have generated plants that appear normal but with spidroins accounting for up to 2% of total soluble protein. NC
Salvia-tion or curse? Health care and legal officials in the USA have growing concern over the use of a legal shamanist drug. Salvia divinorum, http://plants.trends.com
TRENDS in Plant Science Vol.6 No.9 September 2001
commonly known as ska Maria Pastora or diviner’s sage, is a potent hallucinogenic herb that is currently legal in the USA. The plant is native to Mexico and was imported into the USA in the early 1960s. Scientists identified Salvinorum A as the active chemical that causes the hallucinogens. But neurologist Ethan Russo (MT, USA) warns that ‘we don’t know how [Salvia] works. It doesn’t work on serotonin, dopamine or any of the known neurotransmitters.’ Users claim the drug is non-addictive, but its long-term effects are not known. (Deutsche Presse-Agentur 9 July 2001) TS
Keeping photosynthesis in the dark When is an obligate photoautotroph not an obligate photoautotroph? When you genetically engineer it otherwise. Kirk Apt and colleagues have introduced a gene for a human glucose transporter into the marine diatom Phaeodactylum tricornutum [Science (2001) 292, 2073–2075] and converted it from a photosynthetic organism to one that could survive for many days in the dark, fuelled only by exogenously supplied glucose. The work is seen as a major breakthrough in the use of fermentation technology for the commercial exploitation of algae because it reduces previous limitations associated with their lightdependent growth. NC
Transforming iron uptake by rice Nutrient availability severely limits plant growth in many areas of the world. Low levels of nutrient can usually be overcome by adding fertiliser to the crop. Where the problem is due to the plant’s inability to take up sufficient nutrient, genetic engineering can help. Using genetic engineering, Michiko Takahashi and co-workers have created rice plants harboring nicotianamine aminotransferase genes from barley [Nat. Biotechnol. (2001) 19, 466–479]. The genes encode enzymes involved in the production of siderophores, natural iron-chelators secreted by many crop plants, which solubilize iron and enhance its uptake from alkaline soils. Siderophore production in unmodified rice is low, which compromises its ability to grow on alkaline soil. NC
405
No cotton-pickin’ blues? India provides >15% of the world’s cotton. Almost 40% of pesticides used in India are directed at bollworm, which can ravage cotton crops. Cotton genetically modified with Cotton bollworm. Courtesy of Scott Bauer, USDA. the Bt (Bacillus thuringiensis) toxin to combat bollworm has been approved by scientists at India’s Dept of Biotechnology. In spite of the strength of the economic argument in its favor, India’s Environment Dept has recently halted the commercial use of such GM cotton. Notwithstanding extensive trials of the plants, it seems that worldwide ‘the jury is still out’ on the wisdom or otherwise of using this technology. [Nature (2001) 411, 983] NC
As clever as fertilizer... Although it is often essential that we add fertilizer to enhance crop growth, much of that runs off the soil and ends up in rivers rather than in the growing plants. Not only is this an expensive waste, it harms the environment and endangers human health. To avoid these problems, scientists at Penn State University (USA) have developed a system that releases only as much fertilizer as is needed for the plant’s growth requirements. Although currently only available for phosphorus, in trials the ‘smart’ fertilizer improved plant growth and drought tolerance, and prevented up to 90% of the nutrient run-off associated with conventional fertilizers. Similar systems for nitrogen and potassium are planned. (http://www.psu.edu/ur/2001/smartfertilizer. html) NC
From seedy to CD, Linneaus’ herbarium on disk Identification of new plant species often requires reference to herbarium specimens to ensure novelty and to help determine evolutionary relationships between the new and the already known. Unfortunately, in many cases the
1360-1385/01/$ – see front matter © 2001 Elsevier Science Ltd. All rights reserved.