Search

This paper presents the Hybrid and Self-Adaptive Differential Evolution algorithms (HSADE) to solve an egg distribution problem in Thailand. We introduce and formalize a model for a multi-product, multi-depot vehicle routing problem with a time window, a heterogeneous fleet and inventory restrictions. The goal of the problem is to minimize the total cost. The multiple products comprise customers’ demands with different egg sizes. This paper presents a Mixed Integer Linear Programming (MILP) model, an initial solution-based constructive heuristic, a new self-adaptive mutation strategy, and a neighborhood search structure with the probability to improve DE. The two measurements of criteria are the heuristic performance (HP) compared with the solution obtained by MILP and the relative improvement (RI) of the solution compared with Thailand’s current egg distribution practice. The computational results show that the performance of HSADE is better than the current practice, and HSADE can provide on average a 14.13% improvement in total cost. Additionally, our proposed algorithm can be applied to similar agriculture logistics in Thailand and worldwide.

The effect of two different habitats, stored cowpea [Vigna unguiculata (L.) Walpers] pods and seeds, on the dispersal and functional response of Uscana lariophaga Steffan (Hymenoptera Trichogrammatidae) was investigated, with Callosobruchus maculatus (F.) (Coleoptera Bruchidae) eggs as hosts. In the presence of directional light from the top, parasitoids moved faster through columns filled with pods than through columns (either filled with pods or seeds) in darkness. The different habitats, seed or pods, did not have a significant effect on dispersal. The maximal dispersal rate of colonising U. lariophaga females may be up to several meter per day, and median net displacement rates are around 0.5 - 0.8 m per 24 h. The functional response of U. lariophaga could be described by Rogers (1972) random parasitoid equation as a Holling Type II curve and resembles the ones found in earlier experiments. At host densities below 40 eggs per cluster, U. lariophaga was more efficient at finding host eggs in a seed habitat than in a pod habitat, probably due to area restricted searching behaviour after oviposition. At higher host densities, U. lariophaga becomes egg limited, and neither walking behaviour nor the habitat structure significantly influence her foraging success.

Approximately three decades ago the question was first answered “whether parasitoids are able to assess the number or origin of eggs in a host” for a solitary parasitoid, Leptopilina heterotoma, by fitting theoretically derived distributions to empirical ones. We extend the set of different theoretically postulated distributions of eggs among hosts by combining searching modes and abilities in assessing host quality. In the models, parasitoids search either randomly (Poisson) (1) or by vibrotaxis (Negative Binomial) (2). Parasitoids are: (a) assumed to treat all hosts equally, (b) able to distinguish them in unparasitised and parasitised hosts only, (c) able to distinguish them by the number of eggs they contained, or (d) able to recognise their own eggs. Mathematically tractable combinations of searching mode (1 and 2) and abilities (a,b,c,d) result in seven different models (M1a, M1b, M1c, M1d, M2a, M2b and M2c). These models have been simulated for a varying number of searching parasitoids and various mean numbers of eggs per host. Each resulting distribution is fitted to all theoretical models. The model with the minimum Akaike's information criterion (AIC) is chosen as the best fitting for each simulated distribution. We thus investigate the power of the AIC and for each distribution with a specified mean number of eggs per host we derive a frequency distribution for classification. Firstly, we discuss the simulations of models including random search (M1a, M1b, M1c and M1d). For M1a, M1c and M1d the simulated distributions are correctly classified in at least 70 f all cases. However, in a few cases model M1b is only properly classified for intermediate mean values of eggs per host. The models including vibrotaxis as searching behaviour (M2a, M2b and M2c) cannot be distinguished from those with random search if the mean number of eggs per host is low. Among the models incorporating vibrotaxis the three abilities are detected analogously as in models with random search. Experiments with two species of solitary parasitoids (L. heterotoma and Asobara tabida) are conducted. All theoretically postulated distributions are separately fitted to the resulting experimental egg distributions. The AIC criterion is used to choose the best fitting theoretical distribution. For both parasitoid species the frequency distribution of best fitting models for experimental data is compared to the classification of distributions generated by simulations. This leads to the conclusion that both L. heterotoma and A. tabida are able to distinguish between parasitised and unparasitised hosts. For L. heterotoma the results point to an ability to assess the number of eggs in a host, whereas A. tabida does not seem to have this ability. This difference suggests that an egg is more valuable for L. heterotoma than for A. tabida.

The functional value of spawning habitats makes them critically important for the completion of fish life cycles and spawning grounds are now considered to be “essential habitats”. Inter-annual fluctuations in spawning ground distributions of dab (Limanda Limanda), plaice (Pleuronectes platessa), cod (Gadus morhua) and whiting (Merlangius merlangus) were investigated in the southern North Sea and eastern English Channel, from 2006 to 2009. The preferential spawning habitats of these species were modelled using generalised linear models, with egg distribution being used as proxy of spawners’ location. Egg spatial and temporal distributions were explored based on six environmental variables: sea surface temperature and salinity, chlorophyll a concentration, depth, bedstress and seabed sediment types. In most cases, egg density was found to be strongly related to these environmental variables. Egg densities were positively correlated with shallow to intermediate depths having low temperature and relatively high salinity. Habitat models were used to map annual, i.e. 2006 to 2009, winter spatial distributions of eggs, for each species separately. Then, annual maps were combined to explore the spatial variability of each species' spawning grounds, and define recurrent, occasional, rare and unfavourable spawning areas. The recurrent spawning grounds of all four species were located in the south-eastern part of the study area, mainly along the Dutch and German coasts. This study contributes knowledge necessary to the spatial management of fisheries resources in the area, and may also be used to identify marine areas with particular habitat features that need to be preserved.

Para avaliar o comportamento de oviposição da mosca-branca, Bemisia tabaci (Genn.) biótipo B, em relação à posição da folha na planta, à área do limbo foliar, à idade da planta e à densidade de adultos na cultura do pimentão, foram realizados três testes, utilizando-se a cultivar de pimentão Magali-R. Os testes foram realizados em casa-de-vegetação e no Laboratório de Entomologia da DEFERS/UNESP, Campus de Ilha Solteira-SP. Nos testes com chance de escolha, plantas com 25, 30, 35, 40 e 45 dias de idade foram utilizadas para avaliar os efeitos da idade sobre a oviposição da mosca-branca, enquanto que em plantas com 35 dias estudou-se a distribuição de ovos da mosca-branca na planta e no limbo foliar. Em plantas de 35 dias de idade, avaliou-se o efeito de diferentes densidades populacionais do inseto (50, 100, 150, 200 e 250 adultos/ planta) sobre o número de ovos depositados. No teste sem chance de escolha, utilizaram-se plantas com 35 dias de idade para avaliar o efeito das densidades sobre a oviposição da mosca-branca. B. tabaci biótipo B preferiu ovipositar da terceira a sexta folha a partir do ápice da planta localizadas nos terços médio e superior de planta de pimentão e nas áreas do limbo foliar localizadas nos lóbulos direito e esquerdo, próximas à base da folha. Plantas com 40 e 45 dias, são preferidas para oviposição e, em densidades de 200 e 250 adultos por planta, as moscas-brancas depositam ovos em número suficiente para diferenciar genótipos de pimentão com diferentes graus resistência a esta praga. Bemisia tabaci (Gen.) biotype B is considered a pest of economical importance for several vegetables. The oviposition behaviour of the whilefly was evaluated in sweet pepper plants. The trials were carried out under greenhouse condition and in the Laboratory of Entomology of DEFERS/UNESP, Campus of Ilha Solteira-SP, with the sweet pepper Magali-R genotype. The effect of plant age on the whitefly oviposition was evaluated in free-choice tests, in plants, 25, 30, 35, 40 and 45-day-old, as egg distribution in the plant and on the leaf blade was evaluated in 35-days-old plants. In a no-choice tests, 35-day-old plants were used to evaluate the effect of the densities of 50, 100, 150, 200 and 250 adults per plant on the number of eggs laid by insects. The silverleaf whitefly preferred to oviposit on the third to sixth leaflets, of the medium and superior part of plants of sweet pepper; the leaf blade areas, located in the lobes right and left close the base of the leaf were the preferential site for whitefly oviposition. Older plants, 40- and 45-day-old, were preferentially used for oviposition, and 200 and 250 adults per plant were both enough to lay a number of eggs that allowed to differentiate among sweet pepper genotypes with different whitefly resistance levels.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:42:03Z No. of bitstreams: 1 S1519-566X2008000200012.pdf: 160149 bytes, checksum: 64c6c16fe2c791250de43b5aac4c24b5 (MD5) Made available in DSpace on 2013-08-22T18:42:03Z (GMT). No. of bitstreams: 1 S1519-566X2008000200012.pdf: 160149 bytes, checksum: 64c6c16fe2c791250de43b5aac4c24b5 (MD5) Previous issue date: 2008-04-01 Made available in DSpace on 2013-09-30T19:29:02Z (GMT). No. of bitstreams: 2 S1519-566X2008000200012.pdf: 160149 bytes, checksum: 64c6c16fe2c791250de43b5aac4c24b5 (MD5) S1519-566X2008000200012.pdf.txt: 21542 bytes, checksum: fdf0db53f93406566a9574701b02b0db (MD5) Previous issue date: 2008-04-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:07:55Z No. of bitstreams: 2 S1519-566X2008000200012.pdf: 160149 bytes, checksum: 64c6c16fe2c791250de43b5aac4c24b5 (MD5) S1519-566X2008000200012.pdf.txt: 21542 bytes, checksum: fdf0db53f93406566a9574701b02b0db (MD5) Made available in DSpace on 2014-05-20T15:07:55Z (GMT). No. of bitstreams: 2 S1519-566X2008000200012.pdf: 160149 bytes, checksum: 64c6c16fe2c791250de43b5aac4c24b5 (MD5) S1519-566X2008000200012.pdf.txt: 21542 bytes, checksum: fdf0db53f93406566a9574701b02b0db (MD5) Previous issue date: 2008-04-01 Para avaliar o comportamento de oviposição da mosca-branca, Bemisia tabaci (Genn.) biótipo B, em relação à posição da folha na planta, à área do limbo foliar, à idade da planta e à densidade de adultos na cultura do pimentão, foram realizados três testes, utilizando-se a cultivar de pimentão Magali-R. Os testes foram realizados em casa-de-vegetação e no Laboratório de Entomologia da DEFERS/UNESP, Campus de Ilha Solteira-SP. Nos testes com chance de escolha, plantas com 25, 30, 35, 40 e 45 dias de idade foram utilizadas para avaliar os efeitos da idade sobre a oviposição da mosca-branca, enquanto que em plantas com 35 dias estudou-se a distribuição de ovos da mosca-branca na planta e no limbo foliar. em plantas de 35 dias de idade, avaliou-se o efeito de diferentes densidades populacionais do inseto (50, 100, 150, 200 e 250 adultos/ planta) sobre o número de ovos depositados. No teste sem chance de escolha, utilizaram-se plantas com 35 dias de idade para avaliar o efeito das densidades sobre a oviposição da mosca-branca. B. tabaci biótipo B preferiu ovipositar da terceira a sexta folha a partir do ápice da planta localizadas nos terços médio e superior de planta de pimentão e nas áreas do limbo foliar localizadas nos lóbulos direito e esquerdo, próximas à base da folha. Plantas com 40 e 45 dias, são preferidas para oviposição e, em densidades de 200 e 250 adultos por planta, as moscas-brancas depositam ovos em número suficiente para diferenciar genótipos de pimentão com diferentes graus resistência a esta praga. Bemisia tabaci (Gen.) biotype B is considered a pest of economical importance for several vegetables. The oviposition behaviour of the whilefly was evaluated in sweet pepper plants. The trials were carried out under greenhouse condition and in the Laboratory of Entomology of DEFERS/UNESP, Campus of Ilha Solteira-SP, with the sweet pepper Magali-R genotype. The effect of plant age on the whitefly oviposition was evaluated in free-choice tests, in plants, 25, 30, 35, 40 and 45-day-old, as egg distribution in the plant and on the leaf blade was evaluated in 35-days-old plants. In a no-choice tests, 35-day-old plants were used to evaluate the effect of the densities of 50, 100, 150, 200 and 250 adults per plant on the number of eggs laid by insects. The silverleaf whitefly preferred to oviposit on the third to sixth leaflets, of the medium and superior part of plants of sweet pepper; the leaf blade areas, located in the lobes right and left close the base of the leaf were the preferential site for whitefly oviposition. Older plants, 40- and 45-day-old, were preferentially used for oviposition, and 200 and 250 adults per plant were both enough to lay a number of eggs that allowed to differentiate among sweet pepper genotypes with different whitefly resistance levels. UNESP Depto. Fitossanidade, Engenharia Rural e Solos UNESP Depto. Fitossanidade, Engenharia Rural e Solos

δε διατίθεται περίληψη στα ελληνικά, The species composition and seasonal abundance of aphids and their natural enemies were investigated in an apple orchard located in central Peloponnese. For that purpose shoots were collected at weekly intervals. The aphid species Aphis pomi De Geer (Hemiptera: Aphididae), Dysaphis plantaginea (Passerini) (Hemiptera: Aphididae) and Eriosoma lanigerum (Hausmann) (Hemiptera: Eriosomatidae) were recorded. In both years of the study, A. pomi developed higher populations than the other two species. The population of A. pomi was high in June and July. D. plantaginea was present in April and May, with high numbers mainly in May, whilst E. lanigerum was recorded in low numbers from May to July. The number of aphids was not found to differ significantly between samples collected from the northern and southern part of the trees. The species composition of aphid population on each sampled shoot, documented spatial segregation between A. pomi and D. plantaginea. It was proved that the eggs were more commonly laid near the buds of the central part of the twigs. The natural enemies found were predators belonging to the families of Coccinellidae, Chrysopidae, Syrphidae and Anthocoridae. Generally, their numbers were low.

Data on the occurrence of sardine (Sardina pilchardus) eggs from 42 national ichthyoplankton surveys along the European Atlantic coast were collated in order to describe the spawning habitat and spawning distribution of sardine in recent decades (1985–2005). A modification of existing spawning habitat characterisation techniques and a newly developed method to compare the probability of egg presence across surveys carried out with different sampling gears were used. Results showed that sardine spawning off the Atlantic European coast is mainly restricted to the shelf area, with the main geographical range being between the Strait of Gibraltar (the southern limit of data available for this analysis) and the middle part of the Armorican shelf (latitude around 47.5 North), and along a temperature range of 12–17 C. Spawning grounds within these limits show a nearly continuous geographical distribution, covering a large proportion of the shelf of the Iberian peninsula and adjacent waters, except for: (1) a persistent gap at the north west corner of the Iberian peninsula, (2) a small secondary break at the Spanish–French border in the inner part of the Bay of Biscay and (3) at the south west corner of the peninsula where there is a narrowing of the shelf width. These discontinuities were used to separate spawning into four nuclei and to describe the changes in spawning distribution in the time series. The relative importance of each nucleus and the degree of separation between adjacent nuclei varies between years, with the exception of the permanent gap at the northwest corner of the Iberian peninsula, which is persistent throughout the time series. Year to year changes in the proportion of the potential spawning habitat in which spawning actually occurred, changing from around 60% before the mid 1990s to around 40% thereafter, and did not show any relationship with spawning stock biomass. Evolution of potential habitat occupation over the Armorican shelf shows larger variability than that observed in the Iberian peninsula, with percentages of occupation ranging from around 30% up to nearly 80% of the shelf in recent years (within the limitations of the relatively sparse data for this region).

Approximately three decades ago the question was first answered “whether parasitoids are able to assess the number or origin of eggs in a host” for a solitary parasitoid, Leptopilina heterotoma, by fitting theoretically derived distributions to empirical ones. We extend the set of different theoretically postulated distributions of eggs among hosts by combining searching modes and abilities in assessing host quality. In the models, parasitoids search either randomly (Poisson) (1) or by vibrotaxis (Negative Binomial) (2). Parasitoids are: (a) assumed to treat all hosts equally, (b) able to distinguish them in unparasitised and parasitised hosts only, (c) able to distinguish them by the number of eggs they contained, or (d) able to recognise their own eggs. Mathematically tractable combinations of searching mode (1 and 2) and abilities (a,b,c,d) result in seven different models (M1a, M1b, M1c, M1d, M2a, M2b and M2c). These models have been simulated for a varying number of searching parasitoids and various mean numbers of eggs per host. Each resulting distribution is fitted to all theoretical models. The model with the minimum Akaike's information criterion (AIC) is chosen as the best fitting for each simulated distribution. We thus investigate the power of the AIC and for each distribution with a specified mean number of eggs per host we derive a frequency distribution for classification. Firstly, we discuss the simulations of models including random search (M1a, M1b, M1c and M1d). For M1a, M1c and M1d the simulated distributions are correctly classified in at least 70 f all cases. However, in a few cases model M1b is only properly classified for intermediate mean values of eggs per host. The models including vibrotaxis as searching behaviour (M2a, M2b and M2c) cannot be distinguished from those with random search if the mean number of eggs per host is low. Among the models incorporating vibrotaxis the three abilities are detected analogously as in models with random search. Experiments with two species of solitary parasitoids (L. heterotoma and Asobara tabida) are conducted. All theoretically postulated distributions are separately fitted to the resulting experimental egg distributions. The AIC criterion is used to choose the best fitting theoretical distribution. For both parasitoid species the frequency distribution of best fitting models for experimental data is compared to the classification of distributions generated by simulations. This leads to the conclusion that both L. heterotoma and A. tabida are able to distinguish between parasitised and unparasitised hosts. For L. heterotoma the results point to an ability to assess the number of eggs in a host, whereas A. tabida does not seem to have this ability. This difference suggests that an egg is more valuable for L. heterotoma than for A. tabida.

Knowledge of the spatial distribution of stored product insects may reduce the dependency on chemicals for control of these insects. Biological control, for instance, could be improved based on such knowledge. In this paper we describe the three-dimensional spatial oviposition pattern of Callosobruchus maculatus in stored cowpea. Individual C. maculatus females oviposited in clusters of 70±15 (SD) eggs. These clusters were variable in shape. In any cluster 90 to 95 percent of the eggs fitted into a volume of 19.1±3.5 cm3. The egg density was highest (0.6 eggs bean–1) at the center of a cluster and decreased towards the periphery. A statistically significant relationship existed between the number of eggs n in a cluster and the cluster volume, V(cm3): V=11.5 0.11n. We also investigated the spatial egg distribution of beetles which emerged from egg clusters such as those produced by individual females. Their oviposition was not confined to one specific area but was scattered throughout the bean mass. A point pattern analysis showed that the density of the `parent' cluster had no effect on the spatial egg pattern. These results give insight into the foraging environment which the egg parasitoid Uscana lariophaga, a promising candidate for biological control of C. maculatus, is facing. We argue that the probability p of encountering at least one other bean with eggs after a parasitization is a function of the number n of beans that are visited: p=1–0.42 (0.37)(n–1)

Σε κλαδίσκους ελαιοδενδρων και Phillyrea latifolia L. διαφόρων τοποθεσιών των νομών Θεσσαλονίκης και Χαλκιδικής, εγινε καταγραφή της κατανομής των αυγών του Euphyllura phillyreae Foerster (Homoptera. Aphalaridae). Σε ελαιόδενδρα. τα πρώτα αυγά παρατηρήθηκαν το τελευταίο δεκαήμερο του Μαρτίου και η ωοτοκία εντάθηκε μόνον όταν ο κορυφαίος και οι πλάγιοι φυλλοφόροι ή ανθοφόροι οφθαλμοί άρχισαν να φουσκιόνουν. Μόνο σε φουσκωμε'νους οφθαλμούς και σε αναπτυσσόμενες ανθοταξίες διαπιστώθηκαν αυγά. Τα θηλυκά απεθεσαν λίγα μόνο αυγά σε μη φουσκωμε'νους οφθαλμούς, δηλαδή σε οφθαλμούς των οποίων δεν είχε αρχίσει η εκπτυξη. Η προτίμηση για οωτοκία είχε σχε'ση με το στάδιο ανάπτυξης του οφθαλμού και όχι μετη θεση του στον κλαδίσκο. Στους φουσκωμένους οφθαλμούς, τα πλείστα αυγά αποτεθηκαν στην εσωτερική (άνω) επιφάνεια του μεσαίου (δεύτερου) ζεύγους των αναπτυσσόμενων φύλλων και νλιγότερα στην εσωτερική επιφάνεια του πρώτου (εξωτερικού) ζεύγους και στο εσωτερικό (τρίτο) ζεύγος. Στη Phillyrea. τα αυγά αποτεθηκαν πολύ ενωρίτερα από ότι στα ελαιόδενδρα. σε εκπτυσσόμενες ανθοταξίες.Σε εργαστηριακά πειράματα με επιλογή και χωρίς επιλογή, περισσότερα αυγά αποτεθηκαν σε κλαδίσκους ελιάς που είχαν αναπτυγμε'να φύλλα του προηγούμενου έτους και αναπτυσσόμενες (εκπτυσσόμενες) ανθοταξίες, λιγότερα σε κλαδίσκους που είχαν φύλλα και φουσκοψε'νους ακραίο ή πλάγιους οφθαλμούς και κανε'να σε κλαδίσκους που είχαν μόνο αναπτυγμε'να φύλλα., The distribution of eggs of Euphyllura phillyreae Foerster (Homoptera: Aphalaridae) was recorded on twigs of olive trees and of Phillyrea latifolia L. in various locations of the Thessaloniki and Halkidiki prefectures of coastal northern Greece. On olive, the first eggs were observed in the last ten days of March and oviposition was intensified and became abundant only when the apical bud and the axillary leaf and flower buds started to swell. Eggs were laid mostly on swollen buds and on developing inflorescences. Oviposition preference was related to the stage of development of a bud and not to its location on the olive twig. On swollen leaf buds, most eggs were laid on the inner (upper) surface of the middle (second) pair of developing leaves, and fewer on the inner surface of the outer (first) pair and on the innermost (third) pair of leaves. On Phillyrea, eggs were deposited much earlier than on olive, on developing inflorescences. In choice and no-choice laboratory experiments, more eggs were laid on olive twigs bearing developing inflorescences, fewer eggs on twigs bearing only swollen terminal or axillary buds, and no eggs at all on twigs with only fully developed leaves of the previous year.

The effect of two different habitats, stored cowpea [Vigna unguiculata (L.) Walpers] pods and seeds, on the dispersal and functional response of Uscana lariophaga Steffan (Hymenoptera Trichogrammatidae) was investigated, with Callosobruchus maculatus (F.) (Coleoptera Bruchidae) eggs as hosts. In the presence of directional light from the top, parasitoids moved faster through columns filled with pods than through columns (either filled with pods or seeds) in darkness. The different habitats, seed or pods, did not have a significant effect on dispersal. The maximal dispersal rate of colonising U. lariophaga females may be up to several meter per day, and median net displacement rates are around 0.5 - 0.8 m per 24 h. The functional response of U. lariophaga could be described by Rogers (1972) random parasitoid equation as a Holling Type II curve and resembles the ones found in earlier experiments. At host densities below 40 eggs per cluster, U. lariophaga was more efficient at finding host eggs in a seed habitat than in a pod habitat, probably due to area restricted searching behaviour after oviposition. At higher host densities, U. lariophaga becomes egg limited, and neither walking behaviour nor the habitat structure significantly influence her foraging success.