The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), and the carmine spider mite, Tetranychus cinnabarinus (Boisduval), are two of the most important mite pests of different host plants in Egypt. These mites are spreading rapidly because of their resistance to acaricides; therefore, it was necessary to develop a new biological control tactics for mite management. Plant extracts, such as garlic extract (Allium sativum Linn.), may represent easy, available and viable alternative, because they are considered to be minimum-risk pesticides. A series of laboratory and semi-field experiments were considered to determine the susceptibility of adult mite females to different concentrations of garlic aqueous extract (G.A.E.). Mortality was measured upon treatment with five concentrations ranging from 1 to 25% W/V. Female mortality increased with concentration, T. urticae was more tolerant than T. cinnabarinus through laboratory studies as maximum mortality values were 90% and 100% after 24 hours using concentration 25% W/V, respectively. The chemical composition of the Allium sativum aqueous extract was characterized by GC/MS analysis which revealed the occurrence of 33 compounds, of which the major compound was identified as 2-Furancarboxaldehyde,5-(hydroxymethyl). The efficacy of G.A.E. was evaluated against T. urticae and T. cinnabarinus under semi-field conditions. Highest reduction (89.75 %) in T. urticae population was recorded by using concentration 50% W/V one day after treatment (DAT). T. cinnabarinus was more tolerant under the semi-field conditions as the reduction was (80.14 %) using the same concentration. G.A.E. is effective in the control of both tetranychids. It is promising candidates for biological control of these two mite pests.

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Field experiments were carried on soybean variety (Giza 111) during two successive seasons 2019 and 2020. Two natural compounds were tested, Humic acid, Chitosan Nano-particles (C.N.Ps) and a common acaricide, Abamectin, of recommended dose rates and one treatment left without spraying as control by using Economy Micron ULVA sprayer (15L./fed.) and Hydraulic sprayer (Matabi) (56 L/Fed.). Data indicated that all tested compounds induced significant negative influenced on Tetranychus urticae adult females' survival. Abamectin and humic acid revealed successful results followed by the C.N.Ps. Results showed that C.N.Ps have lower toxicity on T. urticae but it safer on all movable stages of Amblyseius californicus, Orius insidiosus, and Scolothrips sexmaculatus, the natural enemies associated. It could be recommended that using those compounds with LV spraying equipment with not less than (15 L. /Fed.). A satisfactory spray coverage was obtained on soybean plants. The droplets spectrum ranging from 150-170 m (VMD). A sufficient number ranging from 18-199 N/cm². The data showed that the Economy Micron ULVA sprayer was the best equipment to control. Tetranychus urticae on soybean according to the homogeneity of the droplet spectrum. The rate of performance of Hand-held Hydraulic sprayer (Matabi) (56 L. /Fed.), Economy Micron ULVA (15 L. /Fed.) were 3.55 Fed. /day, 3.30 Fed. /day, respectively. Data also revealed that lost spray-on ground for Ulva sprayer was lower than Matabi sprayer with 35%.

The efficacy of Fenugreek, Trigonellafoenum graecum, Celery, Apium graveolens Laurel, Laurus nobilis and Thyme, Thymus vulgaris extracts, against the four stored grains pests, rice weevil, Sitophilus oryzae, cowpea beetle, Callosobruchus maculatus, mould mite, Tyrophagus putrescentiae and house dust mite, Dermatophagoides farinae were investigated. Mortality (%) increased with increasing concentrations, exposure periods and varying from plant to plant. Petroleum ether extract of A. graveolens induced 100% mortality after two, eight and seven days of exposure for C. maculates, S. oryzae and D. farinae, respectively. Foenum graecum caused 100% mortality after four, five and seven days for S.oryzae, D. farinae and T. putrescentiae, respectively and 93.3% for C. maculates after five days. Petroleum ether extract of L. nobilis caused 100% mortality to C. maculatus, T. putrescentiae and D. farina but declined to48% with S. oryzae. T. vulgaris caused a complete reduction in F1-progeny for C. maculatus but had no effect against S. oryzae moderate effect on T. putrescentiae and D. farinae. A. graveolens and T. foenumgraecum were the most toxic plants followed by L. nobilis; while T. vulgariswas the least. For all plants, petroleum ether extracts were more effective in mortality percentage and reduction in F1-progeny than acetone extracts.

A sustainable pest management in agro-ecosystems requires parallel assessments of pesticide and natural compounds to control target pests. In the present study, a semi-field experiment was conducted to evaluate the relative toxicity of abamectin (Abamax), humic acid, and Chitosan Nano-Particles (C.N.Ps) against four soybean pests: Tetranychus urticae, Eutetranychus orientalis, Bemisia tabaci, and Phenacoccus solenopsis. The experimental treatments were arranged in a split-plot design with three replicates, where treatments were assigned to main plots and pest populations under different periods in the subplots. The obtained results and graphs demonstrated that there were considerable differences between the total numbers of pests after different periods of treatment. Generally, E. orientalis recorded the minimum pest number at all. Different tested compounds demonstrated a considerable correlation between the densities of the pests. T. urticae exhibited a significant correlation with the other three pests (E. orientalis, B. tabaci, and P. solenopsis). E. orientalis did not correlate with B. tabaci and P. solenopsis. The humic acid recorded the best effect on T. urticae after 3 days with a reduction of 85.45% and E. orientalis after 7 days 65.55%. However, Chitosan Nano-Particles (C.N.Ps) was the best for E. orientalis after 14 days (mortality 74.36%). In contrast, abamectin (Abamax) had a general mean of reduction of 91.17% against T. urticae, whenever, these compounds are promising for controlling T. urticae, E. orientalis, B. tabaci, and P. solenopsis. These results may be a supporting method to overcome some soybean pests. The findings are discussed within the context of integrated management of soybean pests under semi-field conditions.

Modern nanotechnology has been credited as one of the most significant inventions of the 21st century. Many agricultural disciplines have been affected by nanotechnology in agriculture. Pest control based on natural compounds needs to be enhanced, and enhancing plant growth under climate change conditions, with increasing periods of drought in many countries, is a very vital aim. Thus, the effect of curcumin nanoparticles (Cu-NPs) and glycyrrhizic acid nanoparticles (GA-NPs) as a foliar application under water deficit on natural infestation with the two-spotted spider mite Tetranychus urticae, plant growth and yield, anatomical and chemical parameters were investigated during this study. The obtained results revealed that drought stress over the two studied seasons significantly increased the population of T. urticae and decreased all morphological and yield characteristics. The application of three mM GA-NPs reduced the mite population average by 39% while using the same concentration of Cu-NPs caused a 33.9% reduction percentage under drought stress. Using 1 mM GA-NPs gave the highest averages of plant height, number of branches, and leaves/plant fresh and dry weight. Moreover, the number of pods, 100 seed weight and seed yield (kg/ha) increased significantly as a result of spraying with GA-NPs under water deficit. From the results, water deficit decreased the values of the leaf and stem anatomical parameters. Treatment with Cu-NPs or GA-NPs under drought stress increased the thickness of mid-vein, xylem, and phloem tissues. Likewise, such treatment increased stem diameter due mainly to the increase in the thickness of cortex, phloem, and xylem tissues compared with the control. Spraying plants with GA-NPs at 1 mM increased the percentages of nitrogen, phosphor, and potassium in seeds in addition to total chlorophyll. Moreover, glutamate, aspartate, leucine, arginine, Lysine, glycine, tyrosine, tryptophan, and methionine concentrations did not differ significantly (p > 0.05) in response to all the studied levels of Cu-NPs or GA-NPs either under normal irrigation or drought condition. In light of these findings, researchers and producers should apply and test both Cu-NPs and GA-NP as nano-fertilizer natural sources on economically viable crops.

This study aimed to evaluate the insecticidal activity of commercial clove. oil andclove petroleum ether exttact (syzygium aromaticum)on the adults of rice weevil , Sitophilus oi'ae (l'');cowpea beetie ' Callosobntchus maculatus (F'); red flour beelle, Triboleunl casteneum (H.) ;the mould ^1t", Tyroping^ putr"rrrn.llae (shrank) and Dennatophagoides farinae (Shrank) at 30+2oc uno os+ix R.H. Besides, r,11aylrg',h.iffrcacy of clove petroleum ether extract to protect grains dr-rring storage and if it had any effect on ,""A. g".,,,irruiio. p1.,, ar,aiyzingthe ciemical constituents for both extract and commercial oil through GC/MS technique to study the difference in main constituents. Results showed complete mortality (%) at the highest concentration with s.oryzae, c.maalattts arld T'ptirescentiae while T'casteneum arld D' farinae showed high resistance for both oi1 and extract. Accumulative mortality of pests increased gradually with the increase of concentrations and exposure period. The reproduction of females of all experimental pests was completely inhibited at the highest concentration . T. castaneum*u. 1.r, susceptible to tested oils compared with s'otyzae and c'maailafus' The extract was more powerful than commercial oil especiaiiy with T.castene:tm and D' farinae which are known to have high resistance. clove extract give complete plotection tol. g.uio, for 10 weeks with low significant on germination (%)' The main constituents of clove commercial oil were ".,g"n|l (50.58%), cinnamaldehyde (15'72%) and linoleic acid(9'52%)and those of the clove extract were eugenol (37.4;%) "oi.nol acetate (ll'47%i' caryophellene (10'44 %)' linoleic acid (9.42%) and caryophellene oxide (8'58%)'Key words: stored grain pests, clove oil, germination of seeds, Clove extract, residual toxicity and mites'Many researchers used commercial oils to prove its effectivlness against stored grain pests, therefore, this research aims to study the differences of toxicity between commercial oil and oi1 extract in the laboratory, also to study the effect of clove oil extracts in laboratory to protect seeds during storage' MATERIALS AND METHODS