Food

  2010 MAR 11 - (VerticalNews.com) -- According to recent research published in the Allelopathy Journal, "Alleopathy is the process whereby plant releases toxic compounds into environment, resulting in a detrimental effect on neighbouring plants or its own sharing the same habitat. The toxic metabolites are released into environment through volatilization, leaching, decomposition of plant residues in soil and root exudation."

  "The phenomenon was earlier found in agricultural practice by Theophrastus (372 to 285 BC), who reported the inhibitory effect of pigweed on alfalfa. In 1832, De Candolle suggested that the soil sickness problem in agriculture might be due to exudates of crop plants. Since then, many scientists had reported the significance of toxic effects of plant residues decomposing in soil, leading to the reduction in crop productivity. The productivity of many crops (Sorghum bicolor, Medicago sativa, Oryza sativa, Asparagus officinalis, Phaseolus radiatus, Saccharum sinensis, etc.) was reduced significantly after a continuous monoculture. The crop productivity declines due to (i). crops produces phytotoxic substances in soil and (ii). the accumulation of phytotoxins causes the imbalance of microbial population, such as Fusarium oxysporum in soil. These harmful allelopathic effects could be reduced through crop rotation or improving soil drainage in field. In a unique example of pasture and forest intercropping system was demonstrated by the author that an aggressive kikuyu grass (Pennisetum clandestinum), was introduced into the deforested conifer land. The kikuyu grass suppressed the growth of weeds significantly, but was not harmful to the regeneration growth of conifer plants or seeding growth of other hardwood trees. The pasture-forest intercropping system, indeed, benefited the forest management by reducing the use of herbicide, saving expensive manpower, and enhancing forage material for livestock. Finally, the author in recent years have developed a unique system of using the plant parts, leaves, twigs, or roots, of allelopathic plants to make a cocktail of agrochemicals to replace conventional herbicides, fungicides, or insecticides, resulting in avoiding the residual effects of agrochemicals and reducing the environmental deterioration. Using advanced biotechnology, the allelopathic genes can be introduced into crops which possess the allelopathic potential to suppress its competitive weeds in the field," wrote C.H. Chou and colleagues, China Medical University ...read more

  2010 MAR 11 - (VerticalNews.com) -- "Farmland expansion is one of the main causes of steppe loss in northern China. However, an effective land-use change prediction approach has not been available," scientists writing in the journal Environmental Earth Sciences report.

  "A spatially explicit approach designed for identifying the trend of farmland expansion at the village scale was provided here. The first probability estimate model was generated by indicator kriging to predict farmland expansion, and the second was generated using multilevel modeling techniques to identify the causal relationships of farmland expansion," wrote L. Zhang and colleagues, Chinese Academy of Science ...read more

  2010 MAR 11 - (VerticalNews.com) -- "An agricultural ammonia (NH3) emission inventory in the North China Plain (NCP) on a prefecture level for the year 2004, and a 5 x 5 km(2) resolution spatial distribution map, has been calculated for the first time. The census database from China's statistics datasets, and emission factors re-calculated by the RAINS model supported total emissions of 3071 kt NH3-N yr(-1) for the NCP, accounting for 27% of the total emissions in China," investigators in Beijing, People's Republic of China report ...read more