Potential of imidacloprid to control four species of psocids (Psocoptera: Liposcelididae) infesting stored grain

The effectiveness of the neonicotinoid insecticide imidacloprid was evaluated against four psocid pests of stored grain. This research was undertaken because of the growing importance of psocids in stored grain and the need to identify methods for their control. The mortality and reproduction of adults of Liposcelis bostrychophila Badonnel, L. entomophila (Enderlein), L. decolor (Pearman) and L. paeta Pearman in wheat treated with imidacloprid were determined. There were five application rates (0.5, 1, 2, 5 and 10 mg AI kg(-1) grain) and an untreated control. There were significant effects of application rate on both adult mortality and reproduction for all four species, but the effect of imidacloprid was sometimes more pronounced on reproduction. Imidacloprid was most effective against L. bostrychophila, with 100% adult mortality after 7 d at 5 mg AI kg(-1), 14 d at 2 mg AI kg(-1) and 28 d at 0.5 and 1 mg AI kg(-1). No live progeny were produced at 2 mg AI kg(-1). For L. decolor, there was 100% adult mortality after 28 d at 10 mg AI kg(-1) and no live progeny were produced at 2 mg AI kg(-1). For L. entomophila, there was 100% adult mortality after 14 d at 10 mg AI kg(-1) and 28 d at 2 and 5 mg AI kg(-1). No live progeny were produced at 10 mg AI kg(-1). At 10 mg AI kg(-1) there was 100% mortality of L. paeta adults after 28 d exposure and no live progeny developed. Because reproduction at some application rates occurred only in the first 14 d of exposure, it is concluded that the application rate leading to population extinction was 1 mg AI kg(-1) for L. bostrychophila, 2 mg AI kg(-1) for L. decolor and L. entomophila and 5 mg AI kg(-1) for L. paeta. This study shows that imidacloprid has potential as a grain protectant to control all four Liposcelis species in stored grain.     

草地螟选择大画眉草而非藜产卵的证据及原因

为了阐明草地螟对产卵寄主的选择性,为改善其测报、防治技术提供科学依据,笔者于2008年8月在河北康保对草地螟的产卵寄主植物进行了系统的调查。主要结果为:在所调查的9科23种植物中,查到有草地螟产卵的有7科13种。成虫对禾本科的大画眉草[Eragrostis cilianensis(All.)Link ex Vignolo-Lutati]具有显著的偏好。大画眉草的单株着卵量、有卵株率、卵密度及相对着卵量均显著高于藜(Chenopodium album Linnaeus)等其他产卵寄主的对应值,并比藜上的对应值多10倍到100倍以上。对此次草地螟成虫主要选择大画眉草产卵的可能原因进行了探讨分析。     

蓝莓间座壳茎溃疡病病原鉴定及生物学特性研究

在蓝莓园进行病样采集时,发现一种蓝莓茎部病害,病斑呈红褐色,溃疡状,长椭圆形。为明确该病害的病原菌种类,对病枝进行组织分离,经单孢纯化后得到菌落形态一致的7株致病菌,对供试菌株的ITS与EF1-α基因联合构建系统发育树,供试菌株与Diaporthe phaseolorum处于同一分支,结合形态学特征,鉴定该病原菌为Diaporthe phaseolorum。对病原菌的生物学特性研究结果表明,该菌最适培养基为PDA,最适生长温度为25℃,光照对菌丝生长无明显影响。本文首次报道Diaporthe phaseolorum引起蓝莓茎溃疡病。     

Comparative host reactions and Frankliniella occidentalis transmission of different isolates of tomato spotted wilt tospovirus from Spain

The abilities of different isolates of tomato spotted wilt tospovirus (TSWV) collected from northeastern and eastern Spain to infect 10 host species, and to be acquired and transmitted by the western flower thrips (WFT), Frankliniella occidentalis were compared. Two isolates of TSWV from a single source plant could be separated according to the different type of local lesions they induced in Nicotiana glutinosa. Host ranges of the studied TSWV isolates were very similar, but differences were found in the symptoms induced and in their capacity to infect specific hosts systemically. Lycopersicon esculentumDatura stramonium were evaluated for their potential as virus acquisition host species. The proportion of transmitter adult thrips obtained from WFT larvae fed on L. esculentum was greater than from D. stramonium. No differences were detected between TSWV isolates in their ability to be acquired and transmitted by WFT. No evidence was obtained of alterations in TSWV particles which could affect WFT transmissibility due to the repeated mechanical transfers used to clone the isolates. Our findings do not support the existence of pathological effects of TSWV on WFT.     

Effect of plant nectars on adult longevity of the stinkbug parasitoid,Trissolcus basalis

Abstract

The egg parasitoid Trissolcus basalis (Wollaston) (Hymenoptera: Scelionidae) is an important biological control agent of stinkbugs worldwide. Although honey has been used as adult food in culturing the parasitoid, no previous studies have explored the potential for maximising its fitness by provision of plant nectars in conservation biological control. In laboratory experiments, we measured the longevity of adult T. basalis females provided with each of 10 nectar-bearing flowering plant species: Lobularia maritima L., Brassica napus L., Tagetes patula L., Ocimum basilicum L., Fagopyrum esculentum Moench., Cosmos bipennatus Cav., Calendula arvensis L., Coriandrum sativum L., Tropaeolum majus L. and Phacelia tanacetifolia Bentham. Longevity was greatest (33 days) on flowering T. patula shoots and significantly lower on shoots of this species from which the inflorescence had been removed (8 days). Of the other plant species, only L. maritima flowers did not enhance longevity. These results indicate that adults of T. basalis benefit from access to floral nectar and also suggest plant species that merit field testing to identify species best suited to enhancing the efficacy of this parasitoid in conservation biological control.     

Physiologic response of six plant species grown in two contrasting soils and irrigated with brackish groundwater and RO concentrate

With declining availability of fresh surface water, brackish groundwater is increasingly used for irrigation in the arid and semi-arid southwestern United States. Brackish water can be desalinated by reverse osmosis (RO) but RO results in a highly saline concentrate. Disposal of concentrate is a major problem hindering augmentation of inland desalination in arid areas. The objective of this study was to determine the effect of texture and saline water irrigation on the physiology of six species (Atriplex canescens (Pursh) Nutt., Hordeum vulgare L., Lepidium alyssoides A. Gray, Distichlis stricta (L.) Greene, Panicum virgatum L., and ×Triticosecale Wittm. ex A. Camus [Secale?×?Triticum]). All species were grown in two contrasting soils and irrigated with the same volume of control water (EC 0.9?dS/m), brackish groundwater (4.1?dS/m), RO concentrate (EC 8.0?dS/m). Several plant physiological measurements were made during the growing season including height, number of stem nodes, average internodal length, number of leaves, leaf length, photosynthetic rates, stomatal conductance rates, transpiration rates, leaf temperatures, stem water potential, and osmotic potential. P. virgatum was the only species that showed significant decrease in plant height and growth with texture and irrigation water salinity. Except for A. canescens and L. alyssoides, number and length of leaves decreased with increasing salinity for all species. No significant differences were observed for photosynthetic, stomatal conductance, and transpiration rates by soil texture or irrigation water salinity. Stem water potential and osmotic potential did show some significant influence by soil texture and irrigation water salinity. Based on the results, RO concentrate can be reused to grow all six species in sand; however, growth of all species showed some limitations in clay. Local reuse of RO concentrate along desert margins with regular soil and environmental quality monitoring can accelerate implementation of inland desalination for sustaining food security.     

Toxicity of phosphine to five species of stored-product insects in atmospheres of air and nitrogen

The responses of five species of adult stored-product insects [Tribolium castaneum (Herbst), T. confusum (DuVal), Rhyzopertha dominica (F.), Sitophilus oryzae (L.) and S. granarius (L.)] to various doses of phosphine in atmospheres of air or nitrogen were determined. A few S. oryzae and S. granarius survived phosphine concentrations up to 80 mg litre^?1 for 24 h in normal (air) or nitrogen atmospheres. By contrast, T. castaneum, T. confusum and R. dominica could not tolerate more than 0.2 mg phosphine litre^?1 in air for 12 h. However, they could tolerate up to 10 mg phosphine litre^?1 in nitrogen for that period. Increasing the phosphine concentration resulted in increased mortalities of the last three species. The possible mechanism underlying this response is discussed. The reproductive potential of insects surviving phosphine exposure in a nitrogen atmosphere was unaffected.     

Water adaptive traits of deep-rooted C3 halophyte（Karelinia caspica（Pall.） Less.） and shallow-rooted C4 halophyte（Atriplex tatarica L.） in an arid region,Northwest China

This paper focused on the water relations of two halophytes differing in photosynthetic pathway,phenotype,and life cycle:Karelinia caspica (Pall.) Less.(C3,deep-rooted perennial Asteraceae grass) and A...     

Differential host utilisation by different life history stages of the fish ectoparasite Argulus foliaceus (Crustacea: Branchiura)

In this study we examine differences in the occurrence of life history stages of the destructive fish ectoparasite Argulus foliaceus (L., 1758) on eight fish species (stickleback, rudd, roach, gudgeon, bream, tench, crucian carp and common carp) sampled from a mixed-species recreational fishing lake on nine occasions during late spring and summer. Total numbers ofA. foliaceus, as well as the number of larval, juvenile and adult parasite stages, from each fish were recorded along with the fish species. Lice generally exhibited an aggregated distribution approximating a negative binomial distribution. Significant differences in the prevalence, intensity and intensity frequency distribution were observed between life history stages and between host species. In general, all life history stages of A. foliaceus exhibited an over-dispersed distribution. However, larval lice did show some degree of aggregation particularly within the stickleback samples. Infection data for parasite larval stages suggested that sticklebacks are more likely to be infected than other host species. For adult lice, however, carp appeared to be the main host. We propose that A. foliaceus infection characteristics are predominantly determined by the level of host exposure to the parasite and its life history stages (larval, juvenile and adult) rather than by an innate difference in host susceptibility related to individual host factors such as immune responses. We conclude that host exposure is determined by the parasite-host behavioural interplay related to species-specific ecology and behavioural traits such as microhabitat preference and normal swimming speed.     

嘧菌酯与三种外源硒对不同生命阶段斑马鱼的联合毒性

分别测定了嘧菌酯、3种外源硒 (亚硒酸钠、硒代蛋氨酸和纳米硒) 对水体模式生物斑马鱼不同生命阶段的单一急性毒性,以及等毒性配比的二元混合体系的联合急性毒性,并分别采用相加指数 (AI) 法、毒性单位 (TU) 法和混合毒性指数 (MTI) 法对其联合效应进行了评价。结果表明:斑马鱼3个生命阶段对亚硒酸钠的敏感性 (以96 h-LC₅₀ (致死中浓度) mg/L表示,其中mg指硒的质量) 顺序为:仔鱼(1.11 mg/L) >胚胎(1.48 mg/L) >成鱼(13.05 mg/L);对硒代蛋氨酸的敏感性:仔鱼(0.80 mg/L) >胚胎(1.03 mg/L) >成鱼(9.36 mg/L);对纳米硒的敏感性:成鱼(0.48 mg/L) >仔鱼(1.67 mg/L) >胚胎(4.32 mg/L)。除MTI法计算嘧菌酯与硒代蛋氨酸对成鱼表现为部分相加作用外,采用AI法、TU法和MTI法计算嘧菌酯与亚硒酸钠、硒代蛋氨酸和纳米硒对斑马鱼成鱼、仔鱼和胚胎的联合作用结果一致,均表现为拮抗作用。     

Performance of potential non-crop or wild species under OECD 208 testing guideline study conditions for terrestrial non-target plants

The inclusion of 52 potential non-crop or wild species in new OECD guidelines for terrestrial non-target plant (TNTP) testing led to a ring test conducted by four laboratories experienced in regulatory testing. Species selected had shown potential to meet validity criteria of emergence for TNTP studies in a previous evaluation of the 52 species. OECD 208 guideline conditions were applied, with and without seed pretreatments recommended to enhance germination. These species were Abutilon theophrasti (L.) Medic., Avena fatua L., Fallopia convolvulus (L.) Adans., Galium aparine L., Ipomoea hederacea (L.) Jacq. and Veronica persica Poir. Only I. hederacea met the validity criterion of 70% emergence in all laboratories and showed a low variability in biomass. Of the other species, none led to 70% emergence in all four laboratories. The recommended pretreatments did not have a major impact on emergence. Biomass was also investigated with A. theophrasti, A. fatua, Centaurea cyanus L., I. hederacea and Rumex crispus L. Variability of biomass, a key parameter in TNTP regulatory studies, exceeded normal biomass variability of crop species used for TNTP studies. The addition of a thin layer of quartz sand to the soil surface resulted in improved emergence of C. cyanus, G. aparine and V. persica; however, such a procedure, while routine in screening studies to improve germination, is a deviation from the TNTP guidelines. These initial studies indicate that some species could meet the emergence criteria for TNTP testing. However, there is a need for further studies on seed source, seed quality and conditions for uniform emergence before their use in routine regulatory testing.     

Toxicity of δ‐phenothrin and resmethrin to non‐target insects

BACKGROUND: The susceptibility of adult house cricket, Acheta domesticus (L.), adult convergent lady beetle, Hippodamia convergens (Guérin‐Méneville), and larval fall armyworm, Spodoptera frugiperda (JE Smith), to resmethrin and δ‐phenothrin synergized with piperonyl butoxide (PBO) was evaluated in a laboratory bioassay procedure. RESULTS: The 1 day LC₅₀ values for resmethrin + PBO were 23.2, 32.08 and 307.18 ng cm^?2 for A. domesticus, H. convergens and S. frugiperda respectively. The 1 day LC₅₀ values for δ‐phenothrin + PBO were 26.9, 74.91 and 228.57 ng cm^?2 for A. domesticus, H. convergens and S. frugiperda respectively. The regression relationship between species mortality and concentration explained 51–81% of the variation for resmethrin + PBO and 72–97% of the variation for δ‐phenothrin + PBO. The LC₅₀ values decreased with time for these insecticides for all surrogate species. In terms of sensitivities among the insects to resmethrin + PBO and δ‐phenothrin + PBO, A. domesticus was most sensitive, followed by H. convergens and then S. frugiperda. CONCLUSION: The results indicate that resmethrin + PBO was generally more toxic than δ‐phenothrin + PBO. Based on the results, A. domesticus seems to be a good surrogate species for estimating potential non‐target terrestrial insect impacts from exposure to pyrethroids used in public health applications. Copyright © 2008 Society of Chemical Industry     

Control of the mushroom phorid fly, Megaselia halterata (Wood), with plant extracts

BACKGROUND: The most serious insect pest problems affecting the cultivation of mushroom [Agaricus bisporus (Lange) Imbach] in Turkey are mushroom flies (sciarids, cecids and phorids). Mushroom phorid fly, Megaselia halterata (Wood), is the most common insect pest species during April‐October. The aim of this study was to evaluate the potential for eight botanical materials (two commercial neem‐based products and six hot‐water plant extracts) to control M. halterata populations in three successive growing periods. RESULTS: Treatment efficacy was evaluated by assessing adult emergence and sporophore damage rates compared with that of a standard insecticide, chlorpyrifos‐ethyl (positive control). All plant extracts caused significant reductions in the mean number of emerging adults and sporophore damage rates compared with the water‐treated control (negative control). Reduction in adult emergence in both neem treatments, Neemazal and Greeneem oil, was greater than that in the positive control. While Neemazal and Origanum onites L. extract had significantly lower sporophore damage rates than the positive control, there were no significant differences between the chlorpyrifos‐ethyl, Greeneem oil and Pimpinella anisum L. extract treatments. CONCLUSION: The results suggest that both neem products and hot‐water extracts of O. onites and P. anisum may be potential alternatives to conventional pesticides for the control of mushroom phorid fly. Copyright © 2008 Society of Chemical Industry     

Toxicity of spray and fumigant products containing cassia oil to Dermatophagoides farinae and Dermatophagoides pteronyssinus (Acari: Pyroglyphidae)

The toxicity of formulations of oil of cassia, Cinnamomum cassia Blume, (20 and 50 g L(-1) sprays and 100% oil-based fumigant) to adult Dermatophagoides farinae Hughes and D. pteronyssinus Trouessart was examined using contact and vapour-phase toxicity bioassays. Results were compared with the lethal activity of three commercial acaricides: benzyl benzoate, dibutyl phthalate and diethyl-m-toluamide (deet). The contact toxicity of cassia oil to both dust mite species was comparable with that of benzyl benzoate but was higher than that of the other two acaricides. Sprays containing 20 and 50 g L(-1) cassia oil were effective against both mite species when applied to fabric, glass, paper, plastic, tin or wood substrates. Applications of the 50 g L(-1) spray to different space volumes and surface areas determined that 50-60 mg of cassia oil was needed to control dust mites in 3.4 m(3) or in 1 m(2). In tests with fumigant devices, toxicity varied according to the thickness of non-woven fabric covering the device, the exposure time, the number of fumigant devices used and the volume of the space sprayed. Fumigant toxicity to adult D. pteronyssinus was more pronounced with devices enclosed in thinner (40 microm) versus thicker (45 or 50 microm) non-woven fabric covers. A single fumigant device with a 40 microm thick non-woven fabric cover resulted in substantial control in a space of 0.05 m(3) but exhibited only moderate to weak control in spaces >or= 0.097 m(3) at 4 days after application. Two fumigant devices gave 88% mortality in a space of 1.73 m(3). Cassia oil applied as sprays or in fumigant devices appears to provide effective protection of humans from house dust mites.     

Effect of chitin-synthesis inhibitors on stored-product beetles

The fecundity of four important coleopteran stored-grain pests, Rhyzopertha dominica (Fab.), Sitophilus oryzae (L.), Oryzaephilus surinamensis (L.) and Tribolium castaneum (Herbst.) was assessed after exposure to wheat treated with five benzoylphenyl ureas (BPUs), members of the chitin-synthesis inhibitor group of insect growth regulators (IGRs). Chlorfluazuron was found to control all four species more effectively than triflumuron, teflubenzuron, flufenoxuron or diflubenzuron. Two weeks of exposure of parents to 0.5 mg kg ?1 of all the BPUs, except diflubenzuron, inhibited almost all F1 production and all the F2 production of each species. The fecundities of T. castaneum and O. surinamensis recovered almost to their untreated levels after two weeks of exposure to 1 mg kg ?1 of BPUs followed by two weeks on untreated wheat, but the effect of the exposure persisted for at least two weeks on untreated wheat in adult S. oryzae and to a lesser extent in R. dominica. The mean F1 response of the four species after two weeks of exposure to four doses showed clearly that the four newer BPUs were all similar in their overall effectiveness and significantly more effective than diflubenzuron, although diflubenzuron was equally effective against S. oryzae. At 0.1 mg kg ?1 triflumuron was less effective against O. surinamensis, while teflubenzuron and flufenoxuron were not very effective against the rice weevil, S. oryzae. Chlorfluazuron provided the most effective control of all four stored-product pest species, including the weevil, S. oryzae. The BPUs show particular potential for use in the stored-product industry because low dosages will effectively control the rice weevil in addition to the other major pest species.     

西北干旱区白刺属植物适生环境的模拟分析

白刺属(Nitraria L.)植物是古地中海第三纪孑遗植物,对我国西北干旱、半干旱地区具有极高的生态效益。本研究基于MaxEnt模型和ArcGIS软件及其SDM工具箱预测了过去到未来不同时期下白刺属6个物种在我国的潜在适生区及其迁移路线,以期为该属植物的保护及资源利用方面提供一定的理论依据。结果表明:白刺属植物当代在我国的高适生区面积占我国国土总面积的6.32%,主要集中在宁夏北部、内蒙古南部和新疆西部地区。与过去相比,白刺属植物的潜在高适生区在当代减少了1.68%。与当代相比,白刺属植物高适生区预测面积在2070年(RCP4.5)气候情景下减少了0.13%,在2070年(RCP8.5)气候情景下增加了1.61%,主要集中在甘肃东南部和宁夏地区;白刺属植物在我国潜在适生区的主导环境因子是最冷月最低温(bio6);最冷季度的平均降水量(bio19)和年均温(bio1)是影响白刺属潜在地理分布的主要环境因子;白刺属植物在末次间冰期(LIG)、末次冰盛期(LGM)、当代及2070年(RCP4.5和RCP8.5)均有向青海等高海拔地区迁移的趋势。     

苜蓿盲蝽属三种害虫对环氧虫啶的敏感性

环氧虫啶是我国自主研发的一种新型的新烟碱杀虫剂,主要用于防治刺吸式口器害虫。本文采用点滴法测定了环氧虫啶对中黑盲蝽、苜蓿盲蝽、三点盲蝽的毒力,结果表明,三种盲蝽对环氧虫啶均具有较高的敏感性,其中中黑盲蝽的敏感性最高,LD_(50)值为2.03ng/头,其次为苜蓿盲蝽和三点盲蝽,LD_(50)分别为3.12和3.34ng/头。多功能氧化酶抑制剂PBO能明显增加环氧虫啶对三种盲蝽的毒力,谷胱甘肽S-转移酶抑制剂DEM只在中黑盲蝽上对环氧虫啶表现出增效作用,而羧酸酯酶抑制剂TPP未显示增效作用。这说明,环氧虫啶具有防治苜蓿盲蝽属三种害虫的应用潜力,细胞色素P450-单加氧酶可能在环氧虫啶代谢中起重要作用。     

Detection of airborne inoculum of Leptosphaeria maculans and Pyrenopeziza brassicae in oilseed rape crops by polymerase chain reaction (PCR) assays

The potential use of DNA-based methods for detecting airborne inoculum of Leptosphaeria maculans and Pyrenopeziza brassicae , both damaging pathogens of oilseed rape, was investigated. A method for purifying DNA from spores collected using Hirst-type spore samplers and detecting it using polymerase chain reaction (PCR) assays is described. For both pathogens, the sensitivities of the DNA assays were similar for spore-trap samples and pure spore suspensions. As few as 10 spores of L. maculans or P. brassicae could be detected by PCR and spores of both species could be detected against a background of spores of six other species. The method successfully detected spores of P. brassicae collected using spore traps in oilseed rape crops that were infected with P. brassicae. Leptosphaeria maculans spores were detected using spore traps on open ground close to L. maculans -infected oilseed rape stems. The potential use of PCR detection of airborne inoculum in forecasting the diseases caused by these pathogens is discussed.     

新疆大青叶蝉发生及其卵寄生蜂生物学特性

大青叶蝉Cicadella viridis（Linnaeus,1758）（半翅目Hemiptera：叶蝉科Cicadellidae）食性杂,对玉米Zea mays L.等众多农林作物危害严重,亟待防治。寄生蜂作为重要的生物防治因子,对害虫具有良好的防治效果。探究该害虫在新疆的发生及其寄生蜂的寄生生物学特性,可为保护本地寄生性天敌资源和将来人工繁育优势寄生蜂防治大青叶蝉提供基础数据。本研究于2014-2015年在新疆玛纳斯国家湿地公园通过野外观察调查了该地大青叶蝉的生活史,同时进一步采集大青叶蝉卵进行室内饲养和解剖,确定其优势卵寄生蜂的种类、寄生率、羽化率和雌雄性比等寄生生物学特性,并观察记录该寄生蜂的整个发育历程和寿命及其羽化、交配产卵等过程。结果表明,大青叶蝉在新疆玛纳斯国家湿地公园一年发生两代,以卵越冬;发现该害虫的两种卵寄生蜂,其中小斑邻赤眼蜂Paracentrobia exilimaculata Hu & Lin为世界首次报道的大青叶蝉卵寄生蜂,优势寄生蜂长角柄翅缨小蜂Gonatocerus longicornis Nees为国内首次报道的大青叶蝉卵寄生蜂;长角柄翅缨小蜂的自然寄生率平均为49.70%,九月上旬最高,可达74.96%;室内饲养结果显示,在15℃~40℃,随着温度的升高,羽化率和雌雄比均呈现先升高后下降的趋势,符合正态分布曲线;以15%蜂蜜水（蜂蜜：水=1：6）饲养,该寄生蜂从产卵到羽化需要9~16 d（平均14.25 d）,成虫寿命约6~12 d（雌蜂：9.38 d;雄蜂：8.50 d）,且雌蜂一般会比雄蜂的寿命长1~2 d。本研究初步探明了30℃、RH 45%和光周期14L：10D为大青叶蝉优势寄生蜂长角柄翅缨小蜂的最佳饲养条件,且对大青叶蝉卵具有良好的寄生性能,利用该寄生蜂防治大青叶蝉具有良好的应用前景。     

Allelopathic potential of Acacia melanoxylon on the germination and root growth of native species

Water extracts that were obtained from the flowers and phyllodes of Acacia melanoxylon were used to determine their allelopathic potential in relation to the germination and seedling growth of the native species, cocksfoot (Dactylis glomerata), perennial ryegrass (Lolium perenne), and common sorrel (Rumex acetosa), as well as a general biotest specie, lettuce (Lactuca sativa), in laboratory bioassays. The flowers and phyllodes of A. melanoxylon were soaked separately in distilled water in a ratio of 1:1 (w/v) for 24 h in order to prepare the aqueous extracts. Distilled water was used as the control. The seeds of the target species were germinated in Petri dishes and counted daily for up to 7 days. The A. melanoxylon flower extract (100%, 75%, and 50%) decreased the seed germination of D. glomerata, R. acetosa, L. perenne, and L. sativa. The flower extract caused the most reduction in the germination index and germination speed in D. glomerata, L. perenne, and L. sativa. The mean LC₅₀ value of the A. melanoxylon flower and phyllode extracts in relation to the germination inhibition of L. perenne was 43% and 41%, respectively, 40% and 38%, respectively, in R. acetosa, and 53% and 41%, respectively, in L. sativa. All four concentrations of the flower extract proved to be more phytotoxic than the phyllode extract, reducing the root length of all four species, while the phyllode extract decreased the root length of L. perenne and R. acetosa at the 100% concentration. The L. perenne and D. glomerata grass seeds were more sensitive regarding germination, as compared to L. sativa and R. acetosa. The flower aqueous extract of A. melanoxylon was more phytotoxic, as compared to the phyllode aqueous extract, even at the lowest concentration (25%).