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  • Author: S. Mohammadi x
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Geometric Morphometric Study on Geographic Dimorphism of Coding Moth Cydia Pomonella (Lepidoptera, Tortricidae) from North West of Iran

During years 2003-2004, nine geographical populations of codling moth Cydia pomonella (Linnaeus) from 4 north western provinces of Iran were collected. By preparing 575 images from fore wings and 564 from hind wings, a total of 15 and 11 landmarks were determined for fore and hind wings, respectively. With transforming of landmark's geometrical data into partial warp scores, 26 and 18 scores were obtained for fore and hind wings, respectively. Canonical correlation analysis (CCA) revealed significant correlation between environmental parameters and wing shape variables. Among environmental parameters, wind speed showed the highest correlation with wing shape variables whereas, the correlation between latitude, relative humidity as well as amount of precipitation and wing shape variables was low. Considering the effect of various environmental parameters on wing shape, wind speed was determined as important parameter affecting geographic dimorphism. Among the populations collected from different regions, two geographic population pairs; Meshkinshahr-Mahneshan and Zandjan-Khoramdareh were selected as representative of low and high windy regions, respectively. Relative warp analysis (RWA) of fore and hind wings shape variables in the areas with high and low wind showed shorter and wider fore wings as well as slender and narrower hind wings in populations from high windy regions compared with populations from low wind regions. Centroid size of fore and hind wings in high windy area populations were smaller compared with those from low windy ones as revealed by t-test. The results showed aerodynamic shape and small size of wings are as adapted traits for powerful flight and its control in high windy regions.

Summary

Prosopis farcta (Fabaceae) is a native and common perennial weed plant in Iran. In search of environmental-friendly control methods against P. farcta, we discovered the seed feeder moth Nephopterygia austeritella (Lepidoptera; Pyralidae) in central Iran and studied its bioecology for the first time from 2008 through 2009. Infestation pattern, larval feeding behaviour, developmental period, seasonal occurrence and the adverse impact of the moth on the reproductive organs of P. farcta were investigated. Diagnostic morphological characters of the fifth larval instar of N. austeritella are provided. Two gregarious ectoparasitoids were reared and identified as Apanteles subcamilla and Phanerotoma leucobasis (Hymenoptera: Braconidae). Mortality rates of the larvae were 3.03 and 13.44% in 2008 and 2009, respectively. Larvae destroyed 29.6-38.4% of the pods of their host plants. The potential of N. austeritella as an efficient biological control agent in IPM programs against P. farcta is discussed.

Abstract

The capability of a genotype to achieve acceptable yield over a broad range of sub-optimum and suitable conditions is extremely imperative. Late planting and end-season drought stress are two main factors limiting wheat yield in northwest of Iran. In a 2-year field experiment at Miandoab, Iran, the ability of several selection indices to identify drought resistant genotypes under different sowing dates and moisture conditions were evaluated. Six genotypes of differing response to water scarcity were planted at 20-d intervals on three dates from 11 October to 20 November. Drought resistance indices were utilized on the basis of grain yield under end-season drought (Ys) and normal (YN) conditions. Evaluation of MP, HARM, GM, STI, TOL, SSI, RDI, YSI and Yr indicated that late sowing (20 Nov) significantly decreased drought tolerance in all investigated genotypes. However, yield comparisons under normal and terminal drought stress conditions revealed that promising lines (C-81-4, C-81- 10, C-81-14 and C-82-12) had better performance than local checks (Zarrin and Alvand). Furthermore under both moisture conditions C-81-10 genotype had the greatest grain yield. Based on drought indices like as MP, GMP, STI and HARM C-81-10 genotype introduced as the most tolerant genotype to end-season drought stress. Grain yield showed a positive and significant correlation with HARM, GMP, MP, STI and YI indices were more efficient for recognizing high performance genotypes under different sowing dates and diverse moisture stress.

Abstract

Quantifying the privacy loss of a privacy-preserving mechanism on potentially sensitive data is a complex and well-researched topic; the de-facto standard for privacy measures are ε-differential privacy (DP) and its versatile relaxation (ε, δ)-approximate differential privacy (ADP). Recently, novel variants of (A)DP focused on giving tighter privacy bounds under continual observation. In this paper we unify many previous works via the privacy loss distribution (PLD) of a mechanism. We show that for non-adaptive mechanisms, the privacy loss under sequential composition undergoes a convolution and will converge to a Gauss distribution (the central limit theorem for DP). We derive several relevant insights: we can now characterize mechanisms by their privacy loss class, i.e., by the Gauss distribution to which their PLD converges, which allows us to give novel ADP bounds for mechanisms based on their privacy loss class; we derive exact analytical guarantees for the approximate randomized response mechanism and an exact analytical and closed formula for the Gauss mechanism, that, given ε, calculates δ, s.t., the mechanism is (ε, δ)-ADP (not an over-approximating bound).

Abstract

An epidemiological and pathological study of Macracanthorhynchus hirudinaceus infection in a total of 50 wild boars Sus scrofa attila from cane sugar fields of Iranian Khuzestan was performed. The total prevalence of 64.0 % detected is the highest hitherto known by this acanthocephalan species in wild boars and may reflect a very high contamination of the farm lands studied as the consequence of the crowding of the wild boar population in cane sugar fields. Observations prove that this species is a wild boar gut wall perforating acanthocephalan. High burdens may become so pathogenic for the host individual as to be responsible for its elimination from the population. Thus, this acanthocephalan may play a role in the control of the S. scrofa population inhabiting cane sugar fields, only lowly infected boars being able to survive. In this way, M. hirudinaceus may be useful, as the wild boar is a serious pest of field corps and, moreover, causes a variety of damage to cane sugar fields because of using them for shelter and nesting areas. Such high prevalence in wild boars and presumably high contamination of cane sugar fields represent a human infection risk for farmers, as well as for concrete ethnic group minorities in Iran. The numerous M. hirudinaceus human infection cases reported so far, mainly in Asian countries, support such a risk situation.

Abstract

Let D = (V,A) be a finite and simple digraph. A k-rainbow dominating function (kRDF) of a digraph D is a function f from the vertex set V to the set of all subsets of the set {1, 2, . . . , k} such that for any vertex v ∈ V with f(v) = Ø the condition ∪u∈N−(v) f(u) = {1, 2, . . . , k} is fulfilled, where N(v) is the set of in-neighbors of v. The weight of a kRDF f is the value w(f) = ∑v∈V |f(v)|. The k-rainbow domination number of a digraph D, denoted by γrk(D), is the minimum weight of a kRDF of D. The k-rainbow bondage number brk(D) of a digraph D with maximum in-degree at least two, is the minimum cardinality of all sets A′ ⊆ A for which γrk(D−A′) > γrk(D). In this paper, we establish some bounds for the k-rainbow bondage number and determine the k-rainbow bondage number of several classes of digraphs.