Significant decreases in stomatal conductance and transpiration w

Significant decreases in stomatal conductance and transpiration were detected between flooded and control seedlings from AZD7762 purchase a week after the beginning of

the experiment. However ABA concentration in leaves only started to increase after three weeks of flooding, suggesting that stomata closed in the absence of a rise in foliar ABA. Therefore, stomatal closure in waterlogged seedlings does not appear to be induced by ABA, at least during the early stages of flood-stress. The low levels of ABA detected in roots and xylem sap from flooded seedlings indicated that it is very unlikely that the ABA increase in the leaves of these plants is due to ABA translocation from roots to shoots. We propose that ABA is produced in old leaves and transported Caspase inhibitor to younger leaves. Flooding had no effect on water potential or the relative water content of leaves.

Soil flooding reduced root hydraulic conductance in citrus seedlings. This effect was already evident after a week of waterlogging, and at the end of

the experiment, flood-stressed seedlings reached values of root hydraulic conductance below 12% of that of control plants. This reduction was related to down-regulation of the expression of PIP aquaporins. In addition, whole plant transpiration was reduced by 56% after 35 d under flooding conditions. Flood-stress also decreased the pH of sap extracted from citrus roots. Evidence is presented suggesting that acidosis induced by anoxic stress in roots causes gating of aquaporins, thereby decreasing hydraulic

conductance. Additionally, stomata] closure finely balances-out low pH-mediated losses of root hydraulic conductance therefore maintaining stable leaf hydration. QNZ datasheet (C) 2011 Elsevier Masson SAS. All rights reserved.”
“Background: Malaria vectors have acquired widespread resistance to many of the currently used insecticides, including synthetic pyrethroids. Hence, there is an urgent need to develop alternative insecticides for effective management of insecticide resistance in malaria vectors. In the present study, chlorfenapyr was evaluated against Anopheles culicifacies and Anopheles stephensi for its possible use in vector control.

Methods: Efficacy of chlorfenapyr against An. culicifacies and An. stephensi was assessed using adult bioassay tests. In the laboratory, determination of diagnostic dose, assessment of residual activity on different substrates, cross-resistance pattern with different insecticides and potentiation studies using piperonyl butoxide were undertaken by following standard procedures. Potential cross-resistance patterns were assessed on field populations of An. culicifacies.

Results: A dose of 5.0% chlorfenapyr was determined as the diagnostic concentration for assessing susceptibility applying the WHO tube test method in anopheline mosquitoes with 2 h exposure and 48 h holding period. The DDT-resistant/ malathion-deltamethrin-susceptible strain of An. culicifacies species C showed higher LD50 and LD99 (0.67 and 2.

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