Showing 2 results for Detection.
A. H. Jamali-Zavareh A. Sharifi-Tehrani, M. Izadyar, E. Taheri,
Volume 8, Issue 1 (4-2004)
Abstract
Systemic properties of pyroquilon, an anti-blast systemic chemical, used in controlling rice blast disease caused by Pyricularica grisea, was investigated through in vivo tests. Rice plants were treated with pyroquilon as granules in soil. Leaf and stem tissues were collected at different times after treatment and pyroquilon was extracted from tissues and detected by gas chromatography. Treated rice plants were also exposed to disease infection in blast nursery at different times and disease incidence was evaluated one week later. Pyroquilon was detected in leaf tissue one day after treatment (DAT), reached maximum during 4-7 DAT, and then reduced gradually to a nondetectable level after 28 DAT. In stem tissue, change in pyroquilon content was similar to but its quantity was less than that of leaf tissue. On inoculated plants, disease was controlled up to 60% at 2 DAT and completely controlled during 4-28 DAT. The results indicated that pyroquilon could be taken up and systemically translocated in rice plants after applying as granules in soil. Extent of disease control was a good function of pyroquilon content in leaf tissue (R2=0.93) and 2 ppm of compound in leaf could provide 90% control of the disease. In contrast, disease control was not a good function of pyroquilon content in stem tissue (R2=0.30).
M. Khoshravesh, J. Abedi-Koupai, E. Nikzad-Tehrani,
Volume 19, Issue 74 (1-2016)
Abstract
During the past few decades, the southern part of the Caspian Sea has more frequently experienced extreme climatic events such as drought and flood. Trend analysis of hydro-climatic variables was conducted using non-parametric Mann-Kendall test and regression test for Neka basin in the north of Iran. Trends of precipitation and stream flow characteristics including maximum flow, mean flow and low flow indices were analyzed at the annual, seasonal and monthly time scales from 1358 to 1391 (34 years). Results showed a general decrease in annual and winter precipitation and decrease in daily maximum precipitation, with an increased trend in daily maximum precipitation of spring season. A decreasing trend was observed in 7-day low flow in summer for all sub-basins. Annual and monthly mean flows specifically in winter in all sub-basins decreased, but annual maximum flow increased from upstream to downstream. Land use changes showed that deforestation and urbanization increased during 34 years in the mid and downstream sub-basins. The analysis showed that low flow indices and mean flows are strictly sensitive to climate change. Overall, from hydrological perspective, these results indicate that the study region is getting dryer and facing more severe drought events. The results of this study can predict future droughts to make better decisions for irrigation planning and management of water resources.
