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11.
The attack, escape and predation rates for larvae of aphidophagous ladybird Propylea dissecta (Mulsant) and Coccinella transversalis Fabricius were quantified as a potential mechanism leading to the differences in the incidence of cannibalism and intraguild predation. These rates were compared at four larval instars within and between the species. The attack rates of larvae of C. transversalis were significantly higher than those of P. dissecta towards conspecific and heterospecific victims. For both species, third instars exhibited maximum tendency to attack. Escape rates in C. transversalis were higher than P. dissecta. In P. dissecta, the second instars made a greater number of escapes than other conspecific instars after being attacked by same stage cannibal or heterospecific predator. In P. dissecta, first instars suffered maximum mortality due to cannibalism and intraguild predation by conspecifics and heterospecifics of the same and older developmental stage. No larvae of C. transversalis were eaten by P. dissecta of the same stage. These results suggest that the larvae of P. dissecta were more often potential cannibals than intraguild predators, while the reverse was the case in C. transversalis. Based on this finding, it could be predicted that in patchy prey habitats, high rates of larval cannibalism in P. dissecta would occur with a high risk of cannibalism of first instars. Larvae of C. transversalis would respond as intraguild predators, while those of P. dissecta as intraguild prey. The greater size and walking activity of C. transversalis could be possible reason for this tendency.  相似文献   
12.
The objective of this research was to compare the potential of native plants for the phytoaccumulation of heavy metals (HM). Thirteen predominant plant species (including trees, bushes and grasses) namely Ricinus communis, Ipomoea carnea, Cannabis sativa, Parthenium hysterophorus, Acacia nilotica, Dalbergia sissoo, Acacia modesta, Solanum nigrum, Xanthium stromarium, Chenopodium album, Cynodon dactylon, Eleusine indica, and Dactyloctenium aegyptium were collected from the wastewater originated from Hattar industrial estate of Pakistan, Plants shoots and roots were analyzed for heavy metals / metalloid: Pb, Cr, Cd, Zn, Fe, Ni, and As. Among plant species, the accumulation potential for HM varied depending on the type of element. Regardless of the plant species, HM concentrations varied in the order of Fe > Zn > Cr > Pb > Ni > Cd > As. Tree species of R. communis, A. nilotica, A. modesta, and D. sissoo exhibited an enhanced concentrations of metals. Accumulation pattern of Fe, Pb, Cd, and As in plants could be related to the HM composition of soil and wastewater. Most of the species exhibited higher HM composition in the root as compared to shoot. The species that found with greater ability to absorb HM in the root, got higher HM concentrations in its shoot. Shoot tissue concentrations of HM were attained by the species as D. sissoo > A. modesta > A. nilotica > R. communis > I. carnea > C. album > E. indica > P. hysterophorus > S. nigrum > C. sativa > D. aegyptium > X. strumarium > C. dactylon. Based on results, tree plants were noticed as higher accumulators of HM in polluted soils.  相似文献   
13.
Herein, the ecology of genus Propylea, with special reference to its three species — viz. P. dissecta (Mulsant), P. japonica (Thunberg), and P. quatuordecimpunctata Linnaeus is reviewed, with an eye toward its position in natural habitats and amongst other ladybirds and its biocontrol potential. Although Propylea is not as polyphagous as other successful species, it evidences a preference for certain prey, specifically aphids and whiteflies. This genus is a good model for studies of mating, reproduction, sexual selection, etc. Propylea is usually an intraguild prey in the guilds containing ladybirds, such as Harmonia axyridis (Pallas) and Coccinella septempunctata L. It also appears that it retains some intrinsic advantages that aid in the sustenance and survival of the species. Owing to its smaller size and level of victimization in the guild, its biocontrol potential is questionable, but its size disadvantages are counter-balanced by its high intrinsic rate of increase, high predation, reproductive potential, and bioconversion efficiency, as well as the ease with which it can be reared in the laboratory. Further research will be necessary to ascertain clearly the biocontrol potential of Propylea.  相似文献   
14.
Abstract:  The effects of sibling egg cannibalism on sex-dependent development and adult body weight were determined by rearing simultaneously two groups of sibling larvae of ladybirds, viz. Propylea dissecta and Coccinella transversalis individually. The first group included cannibals (i.e. neonates, which took a sibling egg as the first meal and later fed on aphids, Aphis craccivora ) and the other included non-cannibals (reared exclusively on aphids). The cannibal larvae developed faster with heavier adults than non-cannibals. This expedited development and nutritional advantage (increased body weight) was greater in first instars indicating maximum benefit of sibling cannibalism to them. Sibling cannibalism was relatively more advantageous to male than to female ladybirds. Laboratory data predict that the larger size of adults in the field could possibly be the result of sibling egg cannibalism at the neonate level.  相似文献   
15.
Abstract

An investigation was conducted in pots to access the susceptibility of three lepidopteran pests, namely, gram pod borer, Helicoverpa armigera, greater wax moth, Galleria mellonella, and rice moth, Corcyra cephalonica, to two recently described species, Steinernema masoodi, S. seemae, and three indigenous S. carpocapsae, S. glaseri and S. thermophilum entomopathogenic nematodes (EPN). The suitability of these lepidopterans for the in vivo mass production of the nematodes was also estimated. Among the five species of EPN, S. masoodi, S. seemae and S. carpocapsae were found most pathogenic to C. cephalonica, bringing about mortality within 24 h, followed by H. armigera (36, 38 and 48 h, respectively) and G. mellonella (30, 36 and 48 h, respectively). The other species of EPN, viz., S. glaseri and S. thermophilum was the least pathogenic, which killed the larvae of C. cephalonica in 29 and 36 h, respectively, G. mellonella in 48 h, and H. armigera in 38 and 56 h, respectively. Galleria mellonella was found the most suitable host for the mass production of infective juveniles (IJs) of S. seemae, which yielded higher IJs than S. carpocapsae. Helicoverpa armigera was the next best suitable alternate host, which produced maximum IJs in case of S. seemae followed by S. masoodi, S. carpocapsae, S. glaseri and S. thermophilum. Rice moth, Corcyra cephalonica was the least suitable host. The susceptibility of H. armigera to five tested EPN species and susceptibility of G. mellonella and C. cephalonica to S. masoodi and S. seemae are new records.  相似文献   
16.
A series of aminoalkoxy phenyl-substituted naphthalene-1-yl-methanone was synthesized and tested for its anti-hyperglycemic activity in SLM and STZ-S rat models. Some compounds (3b, 4c and 4h) of the series were showing significant anti-hyperglycemic activity in male Sprague-Dawley rats in sucrose-loaded model (SLM) as well as in streptozotocin-induced model (STZ-S). Active compounds were also evaluated for relative binding affinity against glucagon receptor.  相似文献   
17.
Abstract:  Adalia bipunctata (Linnaeus) is a generalist aphidophagous ladybird having a wide prey range. It exhibits complex polymorphism. We reviewed the information on its general characteristics, polymorphism, sexual activity, foraging behaviour, food range and prey suitability, growth and development, heterospecific interactions including natural enemies, and its biocontrol potential. Although a poor biocontrol agent (only successful against aphid, Dysaphis plantaginea in Switzerland), it was used in the past as a good model to test various hypotheses and models facilitating ecological understanding in insects. In the present review, the empirical data are interpreted and inferences drawn and a checklist of its prey is provided.  相似文献   
18.
The ecology of and biological control by multicoloured Asian ladybird beetle, Harmonia axyridis (Pallas) are reviewed. Our emphasis is on assembling and interpreting information on general characteristics, invasion and establishment, sexual activity, foraging and predation, development, survival and reproduction, predator-predator interactions, natural enemies, biocontrol, non-target effects and status of H. axyridis as a pest of fruits. Colonization of H. axyridis for aphid biocontrol in the USA have been successful in terms of its establishment, but its abundance is turning out to be a nuisance to humans. Its harmful non-target impact on beneficial organisms, humans and native species is becoming a debatable issue. The question on its present position, whether it is a biocontrol agent or pest, is a critical issue and discussed. Inferences from the empirical data are made and new avenues for future research are suggested.  相似文献   
19.
Biomechanics and Modeling in Mechanobiology - Atrioventricular heart valves (AHVs) regulate the unidirectional flow of blood through the heart by opening and closing of the leaflets, which are...  相似文献   
20.
The infectivity of entomopathogenic nematode (EPN), Steinernema mushtaqi was tested against legume pod borer, Maruca vitrata, tobacco caterpillar, Spodoptera litura, blue butterfly, Lampides boeticus, red hairy caterpillar, Amsacta moorei, brown bug, Clavigralla gibbosa, mealy bug, Centrococcus somatics, fruit borer, Earias vittella and green bug, Nezara viridula larvae and in vivo mass production of the above-tested species of EPN have been carried out during 2008. S. mushtaqi was found to be more pathogenic to A. moorei, as it brought about 100% mortality within 48 h, than to S. litura, L. boeticus, N. viriduala and E. vittella, as mortality occurred within 72 h; whereas this level of mortality was recorded in C. somatis, C. gibbosa and M. vitrata within 144 h. No mortality was observed in the control treatment. Multiplication of S. mushtaqi and the yield of infective juveniles (IJs) on these insects was the highest (0.94 × 105 IJs/cadaver) from N. viriduala, followed by S. litura (0.76 × 105 IJs/cadaver), L. boeticus as also C. gibbosa (0.31 × 105 IJs/cadaver) and M. vitrata (0.20 × 105 IJs/cadaver). Very poor populations of IJs were found from A. moorei (0.15 × 105 IJs/cadaver) and C. somatics (0.01 × 105 IJs/cadaver). No multiplication of IJs was found from the cadaver of E. vittella. This opens a new hope of utilising S. mushtaqi in the insect pests management programme.  相似文献   
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