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511.
Abstract

Field trials were conducted to measure translocation of pesticides by summer and winter forage/pasture species from soil containing aged residues of heptachlor and, to a lesser extent, dieldrin. Substantial amounts of heptachlor epoxide, and lesser amounts of y‐chlordane were translocated to plants from contaminated soil. Residue levels varied with crop species and stage of plant development. In summer crops residues were higher in soybean> cowpeas>lab‐lab>Sorghum>millet>sweet saccaline at the grazing and mature stages.

Compared to glasshouse studies undertaken previously, residues in crops grown under field conditions were much lower, this apparently reflects the lower soil moisture levels and the reduced rates of translocation.

Heptachlor residues in winter crops were highest in Saia oats > Berseem clover > Haifa clover > Cassia oats > Tetila ryegrass > Schooner barley > Shaftal clover > Hunter river lucerne at the grazing stage. There were no detectable levels in barley and oats at the mature stage. No dieldrin residues were translocated into the various crop species.  相似文献   
512.
Musca domestica L. (Diptera: Muscidae), commonly called the house fly, is a major domestic, medical and veterinary pest that causes irritation, spoils food and acts as a vector for many pathogenic organisms. In this paper, the social and health problems related to housefly are introduced with the associated need to control its population. Physical and chemical methods of house fly control are briefly discussed. The main focus of this review is on the biological control methods for house fly control, that comprise botanical, fungal, bacterial and parasitoid agents. Although several biocontrol agents are still in the nascent stage, some of them (especially fungal and parasitoid agents) have shown reliable field performance and seem to be suitable candidates for commercialization. However, the majority of these laboratory and field studies have been conducted in the temperate region. It remains to be seen whether the application of biocontrol agents would be feasible in tropical environments. The integrated pest management practices, which can provide more reliable field performance, have also been discussed. A multi-dimensional approach that exerts control on all the life stages of house fly, but simultaneously preserves the fly's natural enemies could be an ecologically sustainable way of maintaining the fly populations below maximally acceptable limits.  相似文献   
513.
Wheat (Triticum aestivum L.) is grown as a rainfed crop in the sub-mountainous region of the Punjab state of India, with low crop and water productivity. The present study aims to assess the effect of climate change scenario (A1B) derived from PRECIS—a regional climate model—on wheat yield and water productivity. After minimizing bias in the model climate data for mid-century (2021–2050), evapotranspiration (ET) and yield of wheat crop were simulated using Decision Support System for Agrotechnology Transfer, version 4.5, model. In the changed climate, increased temperature would cause reduction in wheat yield to the extent of 4, 32 and 61 % in the mid-century periods between 2021–2030, 2031–2040 and 2041–2050, respectively, by increasing water stress and decreasing utilization efficiency of photosynthetically active radiation. The decreases in crop water productivity would be 40, 56 and 76 %, respectively, which are caused by decreased yield and increased ET. Planting of wheat up to November 25 till the years 2030–2031 seems to be helpful to mitigate the climate change effect, but not beyond that.  相似文献   
514.
Journal of Material Cycles and Waste Management - Generation of municipal solid waste (MSW) depends upon lifestyle, urbanization and income level of population. Solid waste management is one of the...  相似文献   
515.
Journal of Material Cycles and Waste Management - A great deal of focus has been given to finding a bio-composite film to substitute petroleum-based synthetic plastic in recent years. Many animals...  相似文献   
516.
Environmental Science and Pollution Research - The human coronavirus disease (COVID-19) pandemic is caused by a novel coronavirus; the Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2)....  相似文献   
517.
Environmental Science and Pollution Research - This work presents a novel approach for a double-slope solar desaltification system having parallel array of evacuated annular tube collectors with...  相似文献   
518.
Environmental Science and Pollution Research - The effects of a composite polyphenolic-rich extract (CPRE) on ruminal fermentation, nutrient utilisation, growth performance, excretion of nitrogen...  相似文献   
519.
Environmental Science and Pollution Research - Vasoactive intestinal peptide (VIP) is a neuropeptide that is produced by the lymphoid cells and plays a major role in immunological functions for...  相似文献   
520.
Environmental Science and Pollution Research - The RhoA gene showed an important genotypic association with nicotine dependence and smoking initiation. The current study aims to investigate the...  相似文献   
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