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Greater wax moths (GWM, Galleria mellonella L.) are important pests of Western honey bee (Apis mellifera L.) colonies. The larval moths feed on wax combs, cast honey bee larval skins, pollen, and s...

The nutritional requirements of mosquitoes include both sugar (generally derived from the nectar of flowers) and blood (humans or animals). Mosquitoes express different degrees of preferences towards hosts depending on behavioral, ecological, and physiological factors. These preferences have implications for mosquito-borne disease risk. The present study is directed to reveal the effect of the human blood groups on the fecundity and fertility of the malaria vector Anopheles stephensi. In laboratory tests, mosquitoes were fed on ABO blood groups via artificial membrane feeders, and the level of attraction against different blood groups was tested by the electroantennogram and wind tunnel bioassay under control conditions. Results indicate that the female mosquitoes had a strong preference towards the blood group B, while in the case of females fed on O blood group had the highest digestibility rate. Overall, the human blood type had a significant impact on the fecundity and fertility of female An. stephensi. The highest numbers of eggs are laid, in the case of blood group B, (mean (± SD)) 216.3 (8.81) followed by the AB, 104.06 (7.67), and O, 98.01 (7.04). In the case of blood group B, females attain the highest fertility of about 92.1 (9.98). This study provides novel insight into the ABO blood type host choice of the mosquitoes that are still partially unknown and suggests encouraging personal protection for relevant individuals within communities at risk, which is a useful tool for preventing malaria where the An. stephensi is present as a dominant vector.

Insecticides, essential for crop protection measures, leave behind several toxic residues that can result in a series of human health disorders. Therefore, this study was planned for the determination of residues and adverse effects of insecticides in blood samples of sprayers, pesticide-industry workers and controls by using blood parameters of these individuals as biomarkers. Optimized analytical methods using GC-MS and HPLC for the simultaneous detection of 22 currently used insecticides were adopted. Eight of twenty-seven (22.22%) sprayers' blood samples were found positive for five different insecticides. Eleven of twenty-seven (40.74%) pesticide-industry workers were found positive for eight different insecticides. The blood samples of both the exposed groups, sprayers and industry workers had significantly (P 0.001; Mann-Whitney U-tests) low hemoglobin-Hb concentrations (12.17 ± 2.13 and 12.22 ± 2.37 g/dl respectively) than the average value of the control group with 14.23 ± 2.37 g/dl. The erythrocyte sedimentation rates (ESRs) in sprayers and insecticide industry workers (28.78 ± 20.72 and 28.17 ± 25.14 mm/1st h respectively) were greater significantly (P 0.001; Mann-Whitney U test) than the control blood samples (9.53 ± 3.34 mm/1st h). These results indicate that the exposed individuals have experienced significant hemotoxic effects during insecticide exposure. The study also predicts the risk to exposed individuals in developing countries like Pakistan and demands realization of safety measures to prevent such dangerous effects of pesticide exposures.

Diaphorina citri Kuwayama (Psyllidae: Hemiptera) and Aphis gossypii Glover (Aphididae; Hemiptera) are destructive sap-feeding pests of citrus and cotton, respectively. This study assessed the toxicity potential of indigenous flora of Soon valley and surrounding salt range (Punjab, Pakistan) against D. citri and A. gossypii. Among acetone extracts of 40 plant species, the extracts of Mentha longifolia (L.) Huds., Melilotus officinalis (L.) Pall., Nerium indicum Mill., Datura alba L. and Salvia officinalis L. showed highest psyllid mortality (i.e. 93, 91, 89, 88 and 81%, respectively). Bioassay with most effective extracts further revealed that the most toxic extracts were S. officinalis, N. indicum and M. longifolia with LC50 values of 18.59, 20.27 and 20.73%, respectively. Similar trend of toxicity was observed in case of their LT50 values. These results suggest the putative effectiveness and further biochemical characterization of these plant extracts for the management of D. citri and A. gossypii and other sap-feeding insect pests.

Some plant essential oil constituents, such as monoterpenoids and phenylpropanoids, are promising insecticides in some situations and for certain insect pests. They vary in their toxicity, depending on the target insect. Moths (Lepidoptera) appear susceptible to these compounds, making them of promise for use against greater wax moths (Galleria mellonella Fabricius, (Lepidoptera: Pyrallidae), GWM), an important pest of western honey bee (Apis mellifera Linnaeus. (Hymenoptera: Apidae)) colonies. We determined the LC50 for GWM larvae or LD50 for GWM adults of select compounds (thymol, carvacrol, (S)-(+)-carvone, estragole, citral, linalool, (S)-(−)-limonene, and γ-terpinene). Concentrations between 8 and 2,266 µg/cm3 were mixed into the diets of GWM larvae and doses ranging between 0.08 and 70.3 mg per adult were applied topically to the abdomens of GWM adults. Lethal concentrations and doses were calculated after of 72 h of exposure. All eight compounds showed insecticidal activity against all tested stages of GWMs. Thymol (LC50 µg/cm3 (95% CI) = 21 [9–56], carvacrol = 46 [26–79], citral = 63 [30–134], and carvone = 76 [33–201]) had the highest toxicity toward GWM larvae. The hydrocarbons limonene (296 [231–377]), estragole (466 [354–611]), and γ-terpinene (729 [630–857]) had the lowest toxicity toward GWM larvae. Thymol had the highest toxicity towards GWM adults (LD50 (CI) = 0.5 [0.4–0.8] mg/adult). However, carvacrol (11.6 [10.1–13.6]), linalool (12.9 [9.3–17.8]), and limonene (15.8 [13.1–19.2]) were less toxic to GWM larvae. Our data show that select plant essential oil constituents are promising controls of GWM.

The greater wax moth, Galleria mellonella L., is a natural pest of western honey bee (Apis mellifera L.) colonies. They can overwhelm weakened honey bee colonies and occasionally cause significant losses to the beekeeping industry. In this study, we determined the seasonal abundance (No. moth larvae/hive) of G. mellonela larvae in hives of honey bees located in district Sargodha, Punjab, Pakistan. Our data showed that the maximum moth abundance occurred during the regional dearth period, i.e. May–November. The peak abundance (14.8 ± 3.9 moth larvae/hive) occurred in August. A multiple correlation analysis was used to estimate the association between explanatory variables (multiple weather factors) and the abundance of wax moth larvae in hives, and a stepwise regression analysis was used to find the best explanatory variable for high abundance. All abiotic factors were correlated with the seasonal abundance of greater wax moth larvae but minimum and maximum temperature correlated with moth abundance more t...

Bracon hebetor (Hymenoptera: Braconidae) is a generalist idiobiont ecto-parasitoid that parasitizes a wide range of Lepidoptera and even some phylogenically distant weevil species (Coleoptera; Curculionidae). In the present context, our aim is to find the most suitable host for efficient laboratory rearing of B. hebetor. We compared fitness traits of this parasitoid wasp on five host species, four species belonging to the Lepidoptera, viz. Galleria mellonella (Pyralidae), Helicoverpa armigera and Spodoptera litura (Noctuidae), Sitotroga cerealella (Gelechiidae), and one to the Coleoptera, the alfalfa weevil Hypera postica (Curculionidae). We determined the parasitic potential, paralysis, daily oviposition rate, development time, total adult progeny, sex ratio and survival. Fecundity was followed during five consecutive days and oviposition period was determined, all under laboratory conditions. The best results were obtained on the wax moth larvae (G. mellonella) for which B. hebetor proved the highest biological activity in term of paralysis, parasitism and oviposition as compared to other tested host species. In Galleria mellonella, total eggs laid per female per five days and egg-adult survivorship were higher and sex ratio was highly biased toward females, as compared to Hypera postica. Intermediate biological activities were found on Helicoverpa armigera, Spodoptera litura and Sitotroga cerealella. These contrasting results show that the plasticity of this species could also represent an important fitness cost difference in performance, which is discussed in terms of phylogenetic distance of the host species (particularly Pyralidae). In conclusion, the possible application of these results can be used in the economically important field of biological control and improve storage of products affected by insect pests.

Biomonitoring of people exposed to hazardous materials provides opportunities for early identification of several diseases, particularly in those individuals who are constantly exposed to pesticides, such as pesticide operators and workers in pesticide manufacturing industry. However, data on this hot topic are limited in Pakistan. In this study, insecticide toxic effects and biochemical alterations (i.e., damage in DNA and enzyme activity) were studied in blood samples of occupationally exposed individuals from Punjab, Pakistan. Eight out of twenty-seven blood samples (29.6%) of the pesticide operators were found positive in five insecticides, with the maximum concentration found for chlorpyrifos-methyl (0.039 μg/mL). Eleven out of twenty-seven blood samples (40.7%) of the pesticide industry workers were found positive in eight insecticides, with the maximum concentration found for endosulfan (0.051 μg/mL). Comet tail length was 16.88 ± 4.57 μm in pesticide industry workers and 16.33 ± 3.78 μm in pesticide operators, which were significantly higher (P 0.01) than that recorded in the control group (4.84 ± 2.21 μm). Values of serum cholinesterase (SChE) concentration were slightly lower (P 0.05) in exposed individuals, whereas values of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) concentration were significantly higher (P 0.01) in exposed individuals compared with control group. Exposure duration and total insecticide concentration in blood samples were positively associated with comet tail length, ALT activity, AST activity, and ALP activity, but negatively with SChE. DNA damage was higher in smokers vs. non-smokers. Also, a positive association was found between comet tail length and number of cigarettes per day. Overall, occupational exposure to insecticides can pose serious health risks to pesticide operators and workers in pesticide manufacturing industry, highlighting the necessity of personal protection in those groups for preventing exposure and resultant health disorders.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). After a thorough investigation, the Editors have concluded that the acceptance of this article was partly based upon the positive advice of two illegitimate reviewer reports. The reports were submitted from email accounts which were provided by the corresponding author Christos A. Damalas as suggested reviewers during the submission of the article. Although purportedly real reviewer accounts, the Editors have concluded that these were not of appropriate, independent reviewers. This manipulation of the peer-review process represents a clear violation of the fundamentals of peer review, our publishing policies, and publishing ethics standards. Apologies are offered to the reviewers whose identity was assumed and to the readers of the journal that this deception was not detected during the submission process.

Host plant nutritional quality can directly and indirectly affect the third trophic levels. The aphid–parasitoid relationship provides an ideal system to investigate tritrophic interactions (as the parasitoids are completely dependent for their development upon their hosts) and assess the bottom up forces operating at different concentrations of nitrogen applications. The effects of varying nitrogen fertilizer on the performance of Aphidius colemani (V.) reared on Sitobion avenae (F.) and Aphidius rhopalosiphi (D.) reared on Rhopalosiphum padi (L.) were measured. Parasitism and percent emergence of parasitoids were positively affected by nitrogen fertilizer treatments while developmental duration (egg, larval, and pupal stages) was not affected by increasing nitrogen inputs. In males and females of both parasitoid species, adult longevity increased with the increasing nitrogen fertilizer. Hind tibia length and mummy weight of both parasitoid species increased with nitrogen fertilizer concentrations, as a result of larger aphids. This study showed that nitrogen application to the soil can have important consequences for aboveground multitrophic interactions.

Keeping in view the increasing demand, queen of Apis mellifera L. (Hymenoptera: Apidae) was reared artificially in this experiment at varying diets including royal jelly. Larval duration, pupal duration, weight, and size of pupae were evaluated at different diets including royal jelly. Queen larvae were raised by Doo Little grafting method. Four different diets were mixed with royal jelly and applied to larvae. Fructose, sugar, yeast, and honey were provided to rearing queen larvae along with same amount of royal jelly. Larval and pupal duration were longest (6.15 and 7.5 days, respectively) at yeast and shortest on honey (5.05 and 7.02 days, respectively). Heavier and bigger pupae were recorded on yeast (168.14 mg and 1.76 cm, respectively) followed by diets having sugar and honey. Due to production of heavier and bigger pupae, yeast was considered as best artificial diet for the growing queen larvae. So, in the second part of experiment, different amounts of yeast were provided to growing larvae along with fixed amount (0.5 g) of royal jelly. Survival rates of the larvae and queen bee were 70% and 40% in the 4-g food, 86.7% and 53.3% in the 6-g food, and 76.7% and 50% in the 8-g food. Weight of adult queen bee (1.459±0.191 g) and the number of ovarioles (41.7±21.3) were highest at 8 g of food. Results of this study are helpful for bee-keepers in producing fitter queen bees., {"references":["Büchler, R., S. Andonov, K. Bienefeld, C. Costa, F. Hatjina, N. Kezic, P. Kryger, M. Spivak, A. Uzunov, and J. Wilde, Standard methods for rearing and selection of Apis mellifera queens. Journal of Apicultural Research, 2013. 52(1): p. 1-30.","Crailsheim, K., R. Brodschneider, P. Aupinel, D. Behrens, E. Genersch, J. Vollmann, and U. Riessberger-Gallé, Standard methods for artificial rearing of Apis mellifera larvae. Journal of Apicultural Research, 2013. 52(1): p. 1-16.","Mitsui, T., T. Sagawa, and H. Sano, Studies on rearing honey bee larvae in the laboratory. I. The effect of royal jelly taken from different ages of queen cells on queen differentiation. Journal of Economic Entomology, 1964. 57(4): p. 518-521.","Shuel, R. and S. Dixon, An artificial diet for laboratory rearing of honeybees. Journal of Apicultural Research, 1986. 25(1): p. 35-43.","Ellis, A.M. and G. Hayes Jr, An evaluation of fresh versus fermented diets for honey bees (Apis mellifera). Journal of Apicultural Research, 2009. 48(3): p. 215-216.","Rhein, W., Über die Entstehung des weiblichen Dimorphismus im Bienenstaate. Development Genes and Evolution, 1933. 129(4): p. 601-665.","Peng, Y.-S.C., E. Mussen, A. Fong, M.A. Montague, and T. Tyler, Effects of chlortetracycline of honey bee worker larvae reared in vitro. Journal of Invertebrate Pathology, 1992. 60(2): p. 127-133.","Michael, A. and M. Abramovitz, A method of rearing honey bee larvae in vitro. Journal of Economic Entomology, 1955. 48(1): p. 43-44.","Hoffmann, I., Rearing worker honeybee larvae in an incubator. Bee world, 1960. 41(1): p. 10-11.\n[10]\tRembold, H. and B. Lackner, Rearing of honeybee larvae in vitro: Effect of yeast extract on queen differentiation. Journal of Apicultural Research, 1981. 20(3): p. 165-171.\n[11]\tAsencot, M. and Y. Lensky, The effect of sugars and Juvenile Hormone on the differentiation of the female honeybee larvae (Apismellifera L.) to queens. Life sciences, 1976. 18(7): p. 693-699.\n[12]\tHanser, G. and F. Ruttner, Queen rearing: Biological basis and technical instruction. 1983, Apimondia Publishing House Bucharest, Romania.\n[13]\tAupinel, P., D. Fortini, H. Dufour, J. Tasei, B. Michaud, J. Odoux, and M. Pham-Delegue, Improvement of artificial feeding in a standard in vitro method for rearing Apis mellifera larvae. Bulletin of insectology, 2005. 58(2): p. 107.\n[14]\tVandenberg, J. and H. Shimanuki, Technique for rearing worker honeybees in the laboratory. Journal of Apicultural Research, 1987. 26(2): p. 90-97.\n[15]\tKaftanoglu, O., T.A. Linksvayer, and R.E. Page, Rearing honey bees, Apis mellifera, in vitro I: Effects of sugar concentrations on survival and development. Journal of Insect Science, 2011. 11(1): p. 96.\n[16]\tHladun, K.R., O. Kaftanoglu, D.R. Parker, K.D. Tran, and J.T. Trumble, Effects of selenium on development, survival, and accumulation in the honeybee (Apis mellifera L.). Environmental Toxicology and Chemistry, 2013. 32(11): p. 2584-2592.\n[17]\tThompson, H.M., S. Wilkins, A.H. Battersby, R.J. Waite, and D. Wilkinson, the effects of four insect growth-regulating (IGR) insecticides on honeybee (Apis mellifera L.) colony development, queen rearing and drone sperm production. Ecotoxicology, 2005. 14(7): p. 757-769."]}

Plant quality can directly and indirectly affect the third trophic level. The predation by all the instars of green lacewing, Chrysoperla carnea (S.) (Neuroptera: Chrysopidae) on the cereal aphids, Rhopalosiphum padi (L.), and Sitobion avenae (F.) at varying nitrogen fertilizer levels was calculated under laboratory conditions. Wheat plants were grown on four nitrogen fertilizer levels and aphids were fed on these plants and subsequently offered as food to the C. carnea. Aphid densities of 10, 30, and 90 were offered to first, second, and third instar larvae of green lacewing. Increased nitrogen application improved nitrogen contents of the plants and also the body weight of cereal aphids feeding on them. Aphid consumption by green lacewings was reduced with the increase in nitrogen content in the host plants of aphids. Predation of both aphid species by first, second, and third instars larvae of C. carnea was highest on aphids reared on plants with the lowest rate of fertilization, suggesting a compensatory consumption to overcome reduced biomass (lower aphid size). Total biomass devoured by C. carnea on all nitrogen fertilizer treatments was not statistically different. Additionally, the heavier host prey influenced by the plant nutrition had an effect on the life history characteristics of green lacewings. The larval duration, pupal weight, pupal duration, fecundity, and male and female longevity were significantly affected by the level of nitrogen fertilization to the aphid's host plants, except for pupal duration when fed on S. avenae. This study showed that quantity of prey supplied to the larvae affects the prey consumption and thereafter the life history characteristics of green lacewings.

The green lacewing, Chrysoperla carnea Stephens (Neuroptera: Chrysopidae) is a major generalist predator employed in integrated pest management (IPM) plans for pest control on many crops. Nitenpyram, a neonicotinoid insecticide has widely been used against the sucking pests of cotton in Pakistan. Therefore, a field green lacewing strain was exposed to nitenpyram for five generations to investigate resistance evolution, cross-resistance pattern, stability, realized heritability, and mechanisms of resistance. Before starting the selection with nitenpyram, a field collected strain showed 22.08-, 23.09-, 484.69- and 602.90-fold resistance to nitenpyram, buprofezin, spinosad and acetamiprid, respectively compared with the Susceptible strain. After continuous selection for five generations (G1-G5) with nitenpyram in the laboratory, the Field strain (Niten-SEL) developed a resistance ratio of 423.95 at G6. The Niten-SEL strain at G6 showed no cross-resistance to buprofezin and acetamiprid and negative cross-resistance to spinosad compared with the Field strain (G1). For resistance stability, the Niten-SEL strain was left unexposed to any insecticide for four generations (G6-G9) and bioassay results at G10 showed that resistance to nitenpyram, buprofezin and spinosad was stable, while resistance to acetamiprid was unstable. The realized heritability values were 0.97, 0.16, 0.03, and -0.16 to nitenpyram, buprofezin, acetamiprid and spinosad, respectively, after five generations of selection. Moreover, the enzyme inhibitors (PBO or DEF) significantly decreased the nitenpyram resistance in the resistant strain, suggesting that resistance was due to microsomal oxidases and esterases. These results are very helpful for integration of green lacewings in IPM programs.

BACKGROUND: Entomopathogenic fungi such as Verticillium lecanii (Z.) (Mycotal®) are used for pest control as an alternative to chemical control. In this study, the effect of V. lecanii on cereal aphids is assessed. In addition, an investigation is carried out to determine whether the use of V. lecanii affects the performance of two natural enemies of aphids, the predator Harmonia axyridis (P.) and the parasitoid Aphidius colemani (V.), in no-choice experiments under laboratory conditions. RESULTS: The number of Rhopalosiphum padi (L.) and Sitobion avenae (F.) killed was increased by increasing the concentration of V. lecanii. The timing of application of fungus to aphids affected the efficacy of other biocontrol agents, a parasitoid and a predator. Parasitation by A. colemani (V.) in both cereal aphids (S. avenae and R. padi) was not affected by V. lecanii when aphids were first treated with V. lecanii and then exposed to A. colemani. The emergence of adults from parasitised mummies was, however, lower in infected aphids than in uninfected aphids when the aphids were first exposed to the parasitoids and then treated with fungus. The female sex ratio in the emerging adults was lower in V. lecanii-treated aphids in both species. When aphids were first treated with V. lecanii, 72 h before predation, fewer aphids of both species were consumed by H. axyridis (P.). CONCLUSION: Use of entomopathogenic fungus as a biological control agent could be a complementary strategy in an integrated pest management programme against cereal aphids, but it can reduce the efficiency of other biocontrol agents (parasitoids and predators) when applied simultaneously. © 2012 Society of Chemical Industry

The study was conducted to find the role of physico-morphic plant factors viz., number of gossypol glands, hair density, length of hair, plant height and thickness of leaf lamina per plant in fluctuating the population of thrips ( Thrips tabaci Lind.), jassid ( Amrasca bigutella Dist.) and whitefly ( Bemisia tabaci Genn.) on six genotypes of cotton viz., BT-703, CIM-557, CIM-608, CIM-573, BT-3701 and FH-113. All the genotypes showed significant differences against sucking insect pest population. Whitefly adult population exhibited negative response with gossypol glands on leaf lamina, midrib and vein and also with plant height. Whitefly adult and nymphal population correlated positively with hair density on leaf lamina and vein and length of hair on leaf midrib. The nymphal and adult population of jassid showed positive correlation with gossypol glands on leaf lamina, vein and length of hair on leaf lamina, midrib and vein. Adult and nymph population of jassid revealed negative response with hair density on leaf lamina and midrib and also with plant height and leaf lamina thickness. Thrips population showed negative correlation with gossypol glands on leaf midrib, vein, length of hair on leaf lamina and vein. Thrips population correlated positively with hair density on leaf midrib, thickness of leaf lamina and plant height. The genotypes CIM-608 (3.70/leaf), CIM-608 (5.67 /leaf), BT-703(0.86/leaf), BT-703 (1.14/leaf) and FH-113 (0.34/leaf) were found to be susceptible, whereas FH-113 (2.85/leaf), CIM-557 (3.46/leaf), CIM-573 (0.40/leaf), CIM-557 (0.48/leaf) and BT-703 (0.08/leaf) were resistant to whitefly adult, whitefly nymph, jassid adult, jassid nymph and thrips population respectively.

Predator–prey interactions are influenced by nitrogen availability. Wheat (Triticum aestivum cv. Solstice) plants were provided with four levels of nitrogen and examined the responses of coccinellid predator, Harmonia axyridis to cereal aphids, Rhopalosiphum padi and Sitobion avenae. Increased nitrogen application improved nitrogen contents of the plants and also the body weight of cereal aphids feeding on them. In no-choice feeding trials, H. axyridis consumed more aphids on low fertilised plants, suggesting a compensatory consumption to overcome reduced biomass (lower aphid size). Total biomass devoured by H. axyridis on all nitrogen fertiliser treatments was not statistically different. Logistic regression analysis of the proportion of prey consumed demonstrated that all developmental stages (larval and adult) of H. axyridis exhibited the type II functional response on all nitrogen fertiliser treatments. The rate of successful search (a′) of third and fourth instars and adults were the same across all fertiliser treatments suggesting that nitrogen fertilisation did not affect a′. Maximum handling time for the first instars of H. axyridis on R. padi (3.81 h−1) and S. avenae (4.59 h−1) was on the highest nitrogen treatment while minimum handling time was for the adults of H. axyridis on R. padi (0.20 h−1) and S. avenae (0.20 h−1) on the lowest nitrogen treatment. Handling time varied at varying fertiliser treatments within all instars and affected the predator's efficiency. The functional response curve, rate of successful search and handling time provide the information needed to understand the predator–prey interaction between H. axyridis and these cereals aphids. This could lead to the development of a better strategy for the biological control of R. padi and S. avenae at any particular level of nitrogen fertiliser regime in the field crops.

Increased nitrogen applications to crops influence plant–insect interactions and potentially increase herbivore population growth. The effect of nitrogen applications on the interactions between a wheat host plant, Triticum aestivum, and its herbivores, Sitobion avenae (Fabricius, 1775) and Rhopalosiphum padi (Linnaeus, 1758) was investigated. Adult body weight, fecundity, maturity rate and longevity of the aphids were measured under different nitrogen application on four wheat varieties, Solstice, Einstein, Deben and Alchemy. Adult body weight of R. padi on Alchemy and of S. avenae on Deben was lowest. Fecundity of R. padi was lesser on Deben and Alchemy while fecundity of S. avenae was least on Alchemy. Days to reach maturity were same on all varieties in S. avenae but in R. padi, Deben positively affected the days to reach maturity. Longevity of S. avenae and R. padi was the same on all varieties. N-fertilizer had a positive effect on the adult weight achieved by S. avenae and R. padi. Fecundity and longevity of both species were also positively correlated with N-fertilizer application. In R. padi, N-fertilizer reduced the time to reach maturity but not in S. avenae.

A pot culture study was conducted to assess the ameliorative effect of silicon, Melia azadirachta leaf extract, and sugar beet root extract, each applied individually or in different combinations, on salinity-induced detrimental effects in pea (Pisum sativum L.). Salinity markedly inhibited the growth, various gas exchange attributes, total phenol contents, membrane stability index, and productivity. On the other hand, lipid peroxidation, electrolyte leakage, H2O2 content, antioxidant activities, and leaf free proline and glycinebetaine contents were significantly enhanced by salinity. However, exogenously applied Si and phyto-extracts markedly alleviated the salinity-induced drastic effects on growth, gas exchange attributes, and productivity. Both phyto-extracts supplemented with silicon gave highly salinity mitigating effects by markedly improving growth, gas exchange attributes, enzymatic activities, osmolytes, and yield. The phyto-extracts and Si suppressed lipid peroxidation, electrolyte leakage, and H2O2 content by strengthening the enzymatic and nonenzymatic (proline and glycinebetaine) antioxidant defense system. The phyto-extracts and Si application also checked the root/leaf sodium and chloride contents, but improved the silicon contents. Thus, it can be concluded that exogenous application of silicon in combination with phyto-extracts of M. Azadirachta and sugar beet is a highly effective ameliorative approach to alleviate salinity-induced hazardous effects in plants, especially in pea, grown under a saline regime.

In this investigation, two okra [(Abelmoschus esculentus (L). Moench)] genotypes were used, i.e., salt-sensitive Okra-7080 and salt-tolerant OH-713. Seedlings were subjected to salt stress (EC 6 dS m−1) and supplemented with optimized concentration of silicon (150 mg L−1) to evaluate the changes in physio-biochemical and enzymatic characteristics of okra genotypes. Physiological attributes included measurement of gas exchange parameters (photosynthesis rate, stomatal conductance, transpiration rate, number of stomata and stomatal size) and relative water contents; biochemical parameters included contents of various molecules (total chlorophyll, carotenoids, proline, glycine betaine, total free amino acids and total soluble sugars, total soluble protein, total phenolics and lipid peroxidation) and enzymatic activities (superoxide dismutase, peroxidase and catalase). The results demonstrated that silicon application under saline conditions resulted in significant differences in many traits and it was concluded that silicon was useful in alleviating salt-induced deleterious effects in okra at early growth stage. It was also suggested that enhanced salt tolerance in okra was highly linked with increased osmolyte accumulation and antioxidant activities, due to exogenously applied silicon.

Mango unlubiti (Drosicha stebbingi Green) mango bahcelerinde oburca beslenen bir zararlidir. Mango meyvesinde agir kalite kaybi ve dusuk uretime sebep olmaktadir (Luhanga & Gwinner 1993). Bu calisma zararlinin kontrolu icin yapilmistir. Izolasyon, saflastirma ve amilaz karakterizasyonu Mango unlubitinden yapilmistir. Amilolitik aktivite D. stebbingi ham homojenat icinde 365U / ml iken aseton icinde cokeltme ornek aktivitesi 680 U / ml olmustur. Amilaz aktivitesi icin optimum pH ve sicaklik sirasiyla, 6.4 ve 50-60 oC olmus, bununla birlikte, amilaz aktivitesi, maksimum alt-tabaka (nisasta) konsantrasyonunun% 3’u olmustur. Enzimatik aktivite Pb2 +, nA1- +, Hg2 +, Ni + 2 ve Cu + 2 tarafindan onlenmis, fakat Ca + 2 enzimatik aktiviteyi arttirmistir. Datura (Datura alba), Neem (Azadirachta indica) ve narenciye (Citrus reticulata) gibi dogal bitki ekstraktlari amilolitik aktiviteyi engellemistir. Sodiumdodisylsulphatepoliakrilamid jel elektroforez (SDS-PAGE) ile olculen amilaz molekul agirligi 26 kDa olmustur. Arastirmanin amaci izolasyonu, saflastirmayi ve mango unlubitlerin sindirim enziminin biyokimyasal karakterizasyonunu degerlendirmektir. Bu calisma unlubitlerin etkin kontrolu icin, unlubitlerin sindirim fizyolojisinin daha iyi anlasilmasini saglar. Mango unlubitlerin erginlerindeki sindirim amilolitik aktivitesinin biyokimyasal ozellikleri zararlinin kontrolu icin yeni ufuklar acabilir