فهرست مطالب

Crop Protection - Volume:7 Issue:3, 2018
  • Volume:7 Issue:3, 2018
  • تاریخ انتشار: 1397/05/30
  • تعداد عناوین: 10
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  • Shahzad Iranipour Pages 247-258
    Demographic parameters such as intrinsic rate of increase estimates are of main interest in a wide range of ecological researches. Two widely used uncertainty estimate techniques are bootstrap and jackknife methods. Bootstrap estimates are time-consuming processes that are impossible to use without a computer program. Unfortunately few programs, if any, have been developed for this task. In this study a guideline was offered to prepare a program in Microsoft Excel environment to carry out time-consuming calculations of reproductive life table data in a minute or two by repeatedly pressing a shortcut key.
    Keywords: software, life-history parameters, uncertainty, resampling techniques
  • Saadia M. H. Eassa, Amany M. Balah*, Samy A. Afiah, Abeer E. El-Hadidy Pages 259-271
    Sorghum Sorghum bicolor L. releasing allelochemicals in the soil through their root exudation that functional their associated soil microorganisms and can help in building disease control strategy for increasing sustainability. The obtained results of sorghum rhizospheric exudates exhibited markedly effect on bacterial count in rhizosphere soil. The extract of root exudates profile was tested by two prepared concentrations; 500 ppm and 1000 ppm against the Bipolaris sorokiniana compared to untreated control. The reduction percentages were calculated after four and seven days of fungus growth, the results represented that the reduction over control were 17.53, 45.63% after four days, however after seven days the reductions over control were 17.28, 36.40%. For sorghum root parts, the reduction increase with increasing concentration ranged from 49.71 to 71.67%, the highest reduction was afforded by conc. 1600 ppm while the lowest reduction by 200 ppm. The analysis to identify sorghum allelochemicals was conducted by LC-MS/MS and FTIR afforded; proline, coumaric acid, cinnamic acid, hydroxycoumarin, benzoxazolone, ferulic acid and sorgoleone. While, sorghum root parts extract compounds were; coumaric acid, cinnamic acid, vanillic acid, luteolin3-Hydroxycoumarin, gallic acid, ferulic acid and sorgoleone. It could be used sorghum root exudates and root parts extract in disease bio-control due the effect of secreted biochemical molecules as step toward sustainable agriculture.
    Keywords: Sorghum, allelochemicals, root exudates, rhizosphere, LC-MS-MS, FTIR
  • Raymond Busayo Titilope*, Musa Abdulrasak Kannike Pages 273-281
    Laboratory experiments were carried out to evaluate the susceptibility of six improved cowpea varieties to seed beetle, Callosobruchus maculatus (Coleoptera: Chrysomelidae) attack at a temperature of 29 ± 2 °C and a relative humidity of 65 ± 3%. Fifty grams of each variety were weighed in Kilner jars (250ml) and infested with three females and two males of C. maculatus that were 1-2 days old. Data recorded were the physical characteristics of the cowpea varieties, number of eggs laid, percentage egg survival, number of emerged adults, duration of emergence (DE), mean developmental period (MDP), percentage seed weight loss, percentage seed damage and susceptibility index. The experiment was a completely randomised design with three replications. Results showed that significant differences (p
    Keywords: Grains, insect activity, non-chemical control, resistance, storage
  • Fatemeh Rostami, Nooshin Zandi-Sohani *, Fatemeh Yarahmadi, Leila Ramezani, Karim Avalin Chaharsoghi Pages 283-291
    Habrobracon hebetor Say (Hymenoptera: Braconidae) is one of the parasitoids which is used against various lepidopteran insect pests in Iran. Due to extensive application of chemical pesticides in farms, studying their side effects on natural enemies is necessary in order to evaluate their probable detrimental effects, in case of application in IPM programs. In this study, side-effects of two prevalent insecticides, flubendiamide and azadirachtin, on functional response of H. hebetor to different densities of 5th instar larvae of Ephestia kuehniella Zeller were evaluated in laboratory conditions. Host densities of 2, 4, 8, 16, 32 and 64 were exposed to randomly selected treated females of H. hebetor in Petri dishes. Ten replications were considered for each host density. The control was treated with water. The results revealed a type ΙΙ response for all treatments. This study showed that flubendiamide and azadirachtin had the lowest (0.269h) and highest values (1.822h) of handling times, respectively. Also, the highest and lowest values of searching efficiency were observed in the flubendiamide (0.188h–1) and azadirachtin (0.0396 h–1) treated wasps, respectively. According to the results of the study, flubendiamide may be more compatible with biological control agent in IPM programs.
    Keywords: Behavioral Response, Botanical insecticide, Ectoparasitoid, Integrated Pest Management
  • Carolina A. Guedes *, Valeria Wanderley-Teixeira, Glaucilane Dos Santos Cruz, Kamilla De Andrade Dutra, Clovis Jose Cavalcanti Lapa Neto, Alvaro A. C. Teixeira, Jose V. De Oliveira Pages 293-302
    The essential oils of plants are composed of several volatile compounds, which may have different concentrations and may be determinant for their toxicity. Thus, in this work, sublethal and lethal effects of the compounds, geraniol and citronellal on the biochemical and reproductive parameters of Spodoptera frugiperda were investigated. For the geraniol compound the LD30 of 9.42 mg/g and LD50 of 13.65 mg/g was used, while for the citronellal LD30 of 0.06 mg/g and LD50 of 0.08 mg/g. Pure acetone was used in the control. Third instar caterpillars were treated topically in the prothoracic region by applying 1 μl of the respective compounds with a HamiltonTM 50 μl syringe. After 48 h the caterpillars were macerated in sodium phosphate buffer at a ratio of 4 caterpillars / 5 ml of the buffer, the levels of total protein, total sugar, lipid and glycogen were measured. The daily posture was evaluated in order to determine the periods of pre-oviposition, oviposition, post-oviposition and egg quantity. The results showed a reduction in the concentration of proteins and sugars for both compounds and concentrations studied. There was no change in lipid concentration. Citronellal increased the concentration of glycogen for both concentrations. The oviposition period and the number of eggs were reduced. However, there was no difference for the pre-oviposition and post-oviposition periods. Thus, it is inferred that geraniol and citronellal compounds cause alterations in the biochemical parameters that reflect in the reproduction of S. frugiperda.
    Keywords: armyworm, isolated compounds, nutritional constituents, reproduction
  • Shahzad Iranipour *, Hossein Mahdavi, Ali Mehrvar, Roghaiyeh Karimzadeh Pages 303-314
    Small walnut aphid (SWA) Chromaphis juglandicola is an economic pest of walnut trees. Population fluctuation of SWA was studied in Mamaghan walnut orchards (East Azarbaijan Province, Iran).Three factors affecting population density of SWA, including vertical divisions of canopy (upper and lower half), geographical orientations of canopy (at four levels) and elongation of branch (basal and distal ends), were investigated. Sampling unit was a cluster of five leaves. Totally 128 samples were taken weekly from all strata upon eight chosen trees, repeating 30 times during the season. Natural enemies also were counted. The first SWA individuals were observed early May, consisting of first instar larvae and alate females. A sudden population increase occurred in mid-May. Maximum 40 aphids/leaf were observed in early June with first and second instars dominant, followed by a sudden decline in late June. A small peak was observed at early October. A partial tendency was observed toward north of canopy, at basal half of downward branches. Positive linear correlation between natural enemie's and SWA populations suggests density dependence. Moreover 2-4 week delay was present between them. Trioxys pallidus (Holliday) was dominant natural enemy in the region. Contrary to previous works, overwintering stages of the SWA in the region were predominantly developed stages (third and fourth instars as well as pre-reproductive winged females).
    Keywords: Spatial, temporal, stratified sampling, density dependence, Trioxyspallidus
  • Somayeh Rahimi-Kaldeh, Ahmad Ashouri, Ali Reza Bandani Pages 315-325
    The egg parasitoids of the genus Trichogramma have become one of the most important economic insects, for they are widely used in biological control of Lepidopteran key pests. For that reason, all aspects of their mass production including diapause have been considered over the last few years. In this study, the effect of host quality on the diapause induction of sexual and asexual T. brassicae Bezdenko (Hym: Trichogrammatidae) have been investigated at two temperatures. Maternal generation developed at two distinct temperatures (14 and 20 °C) and they oviposited on four different qualities of Ephestia kuehniella Zeller (Lep: Pyralidae) eggs including fresh eggs, frozen eggs, host eggs with developing embryo and low quality eggs. Data analysis revealed significant influence of temperature and host quality on diapause induction in both sexual and asexual strains. Maximum diapause happened in host eggs with developing embryo even though they were in fetal development. A higher level of diapause was observed in T. brassicae whose maternal generation had developed at 20 °C. The diapause induction in asexual T. brassicae was less than sexual wasps. The results imply that Wolbachia causes a disturbance in the diapause process. The outcomes of this study, which are new, indicate the complexity of diapause and the importance of factors such as host quality which have received less attention in diapause induction.
    Keywords: Diapause, egg parasitoid, host quality, temperature, Wolbachia
  • Oluwole Olakunle Oladele, Abiola Titilayo Aborisade Pages 327-335
    Environmental risks associated with the use of synthetic fungicides have resulted in an emergent trend in plant disease control with focus on the use of botanicals. In this work, the peels of ripe sweet orange fruits were removed, air dried, powdered and extracted with 95% ethanol. The agar diffusion method was used to test the crude extract against the mould, Lasiodiplodia sp. IMI 50324 Which was originally isolated from rotten orange fruits. The extract inhibited mycelial growth of the fungus. The ethanolic extract was subsequently purified by column chromatography and the fractions separately tested for antifungal action. Total phenol contents of fractions and crude extract were both determined. Active fractions were pooled together and analyzed by gas chromatography-mass spectrometry (GC-MS) for structural elucidation. GC-MS revealed that the peel extract contained the flavonoid 5, 6, 7, 8, 3', 4'-hexamethoxyflavone which is commonly called nobiletin. The presence of 5, 6, 7, 8, 3', 4' hexamethoxyflavone in the peel together with the high total phenol content probably account for inhibition of the test fungus.
    Keywords: Orange peel, inhibition, chromatography, antifungal, activity, compound
  • Ogunuyo Ejiro, Lale Ndowa Ekoate Sunday, Zakka Usman*, Kingsley-Umana Emem Basil Pages 337-348
    The effect of infestation and damage by Larger grain borer (LGB), Prostephanus truncatus (Horns) (Coleoptera: Bostrichidae) on nutrient content of some dried processed root and tuber crops (cassava, yam, sweet potato and cocoyam) were investigated in the laboratory at 25-30 ºC and 70-90% R.H. Thirty five grams each of the chips from two varieties of sweet potato, cassava, cocoyam and a variety of yam were separately placed in a 950 ml sized glass jar. The Test Host Crops (THC) were artificially infested with one, two and three pairs of adult LGB. The experiment was conducted using a completely randomized design with each treatment replicated three times and kept for 90 days. Data were taken on final population of adult LGB, weight of powder and percentage weight loss. Data on proximate analysis of LGB-infested THC after 90 days was also collected. The response of roots and tubers to infestation by LGB on the THC was significantly different. Percentage loss in quantity of root and tuber crops after 90 days of infestation showed that THC infested with two pairs of the insect had higher weight loss of the crops. The THC infested with two pairs of LGB had higher moisture content and least crude protein was recorded on the THC infested with one pair of LGB while the ones infested with three pairs of LGB had higher crude fat content. Uninfested THC had higher carbohydrate content. The findings of this study show that LGB is a serious threat to stored roots and tubers and to food security. The nutritional value of root and tuber crops was adversely affected by infestation of LGB in storage.
    Keywords: Prostephanus truncatus, proximate analysis, infestation, density, nutritional composition
  • Sabrine Mannai, Najwa Benfradj, Najet Horrigue-Raouani, Naima Boughalleb-Mhamdi * Pages 349-363
    Three types of composts (T1, T2, and T3) composed of variable percents of bovine, ovine, fowl manures, green waste and olive pomace were used in this study. Composts were effective in controlling Fusarium oxysporum and Fusarium solani associated with peach decline. In vitro evaluation of four doses of the three composts extracts against mycelium growth of F. solani and F. oxysporum showed that the compost extracts have a significant effect on mycelial growth. The highest inhibition percent was obtained with 10% dose for the three compost extracts, with values more than 48.8% and 50% of F. solani and F. oxysporum, respectively. However, the filtration of the tea composts revealed to be ineffective against the hyphal reduction for both pathogens. The in- vivo experiments exhibited the efficacy of these composts in reducing the seedlings root rot. In fact, T1, T2 and T3 reduced the root rot and browning of plants inoculated with F. solani by 50.19% and plants inoculated with F. oxysporum by 41.86%, 46.45% and 48.3%, respectively. Furthermore, these composts seemed to improve the sanitary state of peach seedlings inoculated with F. oxysporum. However, the improvement of sanitary state of peach inoculated with F. solani was just noted in case of the composts T1 and T2. The treatment of peach seedlings with these improved plant growth by increasing height and root weight of seedlings inoculated with F. oxysporum. However, none of these composts was able to stimulate growth of plants inoculated with F. solani. Root weight of plants inoculated with F. solani was negatively correlated with bovine manure in the compost, positively with fowl (r = 0.69) and sheep manure content (r = 0.69). Besides, a significant negative correlation among sanitary state index of plants inoculated with F. oxysporum in the case of olive pomace (r = -0.92) and the polyphenols content (r = -0.74) of compost was found.
    Keywords: Compost extracts, peach decline, Fusarium spp., in vitro, in vivo inhibition