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Mirhaghparast S.K.,Guilan University | Zibaee A.,Guilan University | Hoda H.,Iranian Institute of Plant Protection | Sendi J.J.,Guilan University
Journal of Plant Protection Research | Year: 2015

The effects of pyriproxyfen were determined on the cellular immunity and phenoloxidase activity in the 4th instar larvae of Chilo suppressalis Walker. The bioassay results revealed the effective concentrations of: 10L: 18C, 30L: 72C and 50L: 190C μg·ml-1. The sole effect of 18 and 72 μg·ml-1 concentrations at intervals of 1-3 h caused a higher number of total hemocytes in the treated larvae than the control, but the reverse results were observed after 6-24 h. The number of plasmatocytes was lower than that of the control for intervals of 3-24 h but the number of granulocytes was higher than the control after 1-3 h although no significant differences were observed at the other times. In the treated larvae, the activities of phenoloxidase were higher and lower than those of the control after 1-3 h and 6-24 h, respectively. The combined effects of pyriproxyfen and the entomopathogenic fungus, Beauveria bassiana isolate B3 caused higher numbers of total hemocytes, plasmatocytes, and granulocytes in the treated larvae by use of the three concentrations of pyriproxyfen, at intervals of 6 and 12 h. Although the numbers of nodules in the larvae treated with concentrations of 18 μg·ml-1 were higher than those of other treatments, the overall numbers were lower than those of the control. Finally, the activity of phenoloxidase in the treated larvae was higher than that of the control, at intervals of 6 and 12 h post-treatment. Findings of the current study indicate an intervening role of pyriproxyfen in the cellular immunity of C. suppressalis to entomopathogenic objects. © Seyyedeh Kimia Mirhaghparast et al. 2015.

Mirhaghparast S.K.,Guilan University | Zibaee A.,Guilan University | Hoda H.,Iranian Institute of Plant Protection | Fazeli-Dinan M.,Mazandaran University of Medical Sciences
Archives of Biological Sciences | Year: 2015

In the current study, two phenoloxidases (POs) from the larvae of Chilo suppressalis Walker were extracted and purified by column chromatography using Sepharyl G-100 and DEAE-Cellulose fast flow column. Two proteins possessing PO activity, named as POI and POII, were extracted by purification, 5.08- and 5.62-fold, respectively, with 8.94% and 7.31% recoveries, respectively. Also, the specific activities of POI and POII were 0.478 and 0.529 U/mg protein, respectively. Finally, the molecular weights of POI and POII were calculated as 94.6 and 95.7 kDa, respectively. Kinetic parameters of the purified phenoloxidases by Lineweaver-Burk analysis were Vmax of 2.27 and 1.11 U/mg protein and Km of 15.51 and 17.31 mM for POI and POII, respectively. Mg2+ and Cu2+ significantly increased thePO activities. Ca2+ decreased the activity of POI and showed no statistical effects on POII activity. EDTA and DTC significantly inhibited the activities of the purified enzymes, while triethylenetetramine hexaacetic acid (TTHA) and RGTA showed no significant effects on enzymatic activities.

Mirhaghparast S.K.,Guilan University | Zibaee A.,Guilan University | Sendi J.J.,Guilan University | Hoda H.,Iranian Institute of Plant Protection | Fazeli-Dinan M.,Mazandaran University of Medical Sciences
Pesticide Biochemistry and Physiology | Year: 2015

Efficient control of Chilo suppressalis Walker is always controversial due to highly economic damage, resistance to insecticides and environmental pollutions. So, combination of safe pest controls e.g. biocontrol agents and insect growth regulators seems to be promising via integrated pest management program. Bioassay of hexaflumuron on 4th larval instars revealed concentrations of 44.34, 179.74 and 474.94μg/ml as LC10-50 values. Numbers of total hemocytes, plasmatocytes and granulocytes as well as phenoloxidase activity increased in the different time intervals following treatment by hexaflumuron. Combined effects of hexaflumuron and Beauveria bassiana Vuillemin also increased hemocyte numbers and phenoloxidase activity at different time intervals using all concentrations. Activities of general esterases assayed by α- and β-naphtyl acetate and glutathione S-transferase using CDNB and DCNB increased 1-12h post-treatment. Activities of aspartate aminotransferase, alanine aminotransferase, γ-glutamyl transferase and aldolase increased in the larvae treated by hexaflumuron. However enhanced activity of lactate dehydrogenase was only obtained by treating 180 and 470μg/ml concentrations of hexaflumuron. Activities of ACP and ALP were found to be higher than control for all time intervals even 1-12h post-treatment. The amounts of HDL and LDL increased in the highest concentrations of hexaflumuron after 12-24h of post-treatment. Amount of triglyceride was higher than that of control after 1 and 3h but it was lower in other time intervals. Amounts of glycogen and protein were lower than those of control for all time intervals except for 6 and 12h of post-treatment in case of protein. Results of the current study revealed negative effects of hexaflumuron on intermediary metabolism of Chilo suppressalis but it increased the number of hemocytes and activity of phenoloxidase which are responsible for spore removal from hemolymph. It can be concluded that hexaflumuron is able to decrease survival and biological performance of C. suppressalis via intervening in intermediary metabolism but the given results showed incompatibility of the IGR with possible microbial control. © 2015 Elsevier B.V.

Jimenez-Mejias P.,Pablo De Olavide University | Martin-Bravo S.,Pablo De Olavide University | Amini-Rad M.,Iranian Institute of Plant Protection | Luceno M.,Pablo De Olavide University
Plant Biosystems | Year: 2014

The morphology of the Eurasian Carex acuta L. has remained poorly characterized, which has allowed its traditional usage as a taxonomic hotchpotch, in which other similar taxa have been included. In this study, we clarify the taxonomic status of C. acuta and assess the delimitation of two similar species found in the southern part of the C. acuta range: Carex panormitana Guss. and Carex kurdica Kük. ex Hand.-Mazz. To this purpose, we performed a detailed morphological study of 101 vouchers from 19 herbaria, including the type material of the three studied taxa and additional related species. Some distinct populations previously regarded as C. acuta were ascribed to C. panormitana or C. kurdica. Detailed morphological descriptions are provided for C. acuta, C. kurdica and C. panormitana. The ranges of the three taxa are revised in the Central-Eastern Mediterranean and the Middle East, and new records of C. panormitana in North Africa and of C. kurdica in Eastern Europe and Mediterranean Anatolia are presented. An epitype is proposed for C. kurdica to complement the identity of the lectotype, as this is immature. © 2014 © 2013 Societá Botanica Italiana.

Shojaei T.R.,University Putra Malaysia | Salleh M.A.M.,University Putra Malaysia | Sijam K.,University Putra Malaysia | Rahim R.A.,University Putra Malaysia | And 3 more authors.
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2016

Due to the low titer or uneven distribution of Citrus tristeza virus (CTV) in field samples, detection of CTV by using conventional detection techniques may be difficult. Therefore, in the present work, the cadmium-telluride quantum dots (QDs) was conjugated with a specific antibody against coat protein (CP) of CTV, and the CP were immobilized on the surface of gold nanoparticles (AuNPs) to develop a specific and sensitive fluorescence resonance energy transfer (FRET)-based nanobiosensor for detecting CTV. The maximum FRET efficiency for the developed nano-biosensor was observed at 60% in AuNPs-CP/QDs-Ab ratio of 1:8.5. The designed system showed higher sensitivity and specificity over enzyme linked immunosorbent assay (ELISA) with a limit of detection of 0.13 μg mL− 1 and 93% and 94% sensitivity and specificity, respectively. As designed sensor is rapid, sensitive, specific and efficient in detecting CTV, this could be envisioned for diagnostic applications, surveillance and plant certification program. © 2016 Elsevier B.V.

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