Evaluation of weed eradication programs: the delimitation of extent

Eradication is a management strategy that can provide substantial ecological and economic benefits by eliminating incursions of pest organisms. In contrast to eradication efforts that target other pests, weed eradication programs can be very protracted owing to the presence of persistent seed banks and difficulties in detecting the target. Hence there is a need to develop criteria to assist in the evaluation of progress towards eradication. Knowledge of the extent of a weed incursion (the ‘delimitation’ criterion) is considered fundamental for eradication success, as an incursion will progress from any infestations that remain undetected and thus uncontrolled. This criterion is examined with regard to eradication programs targeting Bassia scoparia L. A.J. Scott [= Kochia scoparia L. Schrader], Chondrilla juncea L. (both in Western Australia) and Orobanche ramosa L. in South Australia. The B. scoparia incursion, which has been eradicated, was largely delimited within 12 months of the inception of its eradication program. In contrast, the Western Australian C. juncea incursion has never been delimited, owing to insufficient investment in surveillance during an eradication program spanning 30 years. An exponential decrease in the detection ratio (infested area detected/area searched) over time suggests that delimitation has been approached within 6 years of the inception of the eradication program for O. ramosa. An effective surveillance program is essential for achieving delimitation of a weed incursion.     

牛血清白蛋白与地肤提取物N-反式阿魏酰酪胺相互作用研究

该研究以一年生白及幼苗为材料,通过测定生物量、氨基酸含量、蛋白质及多糖含量的变化,研究不同浓度的芸苔素内酯（BR）、萘乙酸（NAA）和茉莉酸甲酯（Me JA）喷施对白及幼苗假鳞茎快速生长发育影响。结果表明：1.6 × 10 4 mmol·L 1的BR处理组,假鳞茎鲜重达3.39 g/株,高于其他处理组,分别是清水对照(CK1)和沼气肥对照组(CK2)的1.19倍和1.25倍;单个假鳞茎（单株）的新生萌芽数也高于其他处理,达到2.17个,说明生产效益至少可提高19%。把两个对照组和三种植物生长调节物质处理后假鳞茎产量最高的处理组（即1.6 ×10 4 mmol·L 1的BR、0.5 mmol·L 1的NAA和0.25 mmol·L 1的Me JA）进一步测定假鳞茎氨基酸、蛋白质和多糖含量,发现CK2氨基酸含量最高,高达8.58%,而CK1含量最低,仅为5.21%,三种植物生长调节物质处理组分别是7.26%、7.53%和5.69%。蛋白质含量由高到低依次是沼气肥对照组、1.6 ×10 4 mmol·L 1 BR、0.5 mmol·L 1 NAA、0.25 mmol·L 1 ME JA和清水对照组,它们的含量分别是11.6%、11.0%、10.5%、9.14%、7.72%,这说明与氨基酸含量基本一致。三种植物生长调节物质处理后白及多糖含量分别为24.2%、26.5%、26.5%,均远高于清水对照（19.3%）和沼气肥对照（21.8%）。综合分析认为,1.6 ×10 4 mmol·L 1的BR能同时提高白及假鳞茎的产量和质量。该研究结果对于白及规模化种植栽培具有重要指导意义。     

荒漠草原不同土壤条件下猪毛蒿幼苗种群的点格局分析

采用摄影定位法测定了宁夏荒漠草原3种不同土壤条件下猪毛蒿（Artemisia scoparia）幼苗种群的空间格局,并应用完全空间随机模型、泊松聚块模型和嵌套双聚块模型对其分布格局进行了分析。结果表明：（1）在灰钙土生境下,猪毛蒿幼苗种群在小尺度上（0-2.85m）表现为聚集分布,随着尺度的增大先呈现为随机分布（2.85-3.75 m）,然后又呈现为均匀分布（3.75-5m）;在风沙土生境下,猪毛蒿幼苗种群在0-1.85 m之间表现为聚集分布,在1.85-2.35 m之间表现为随机分布,当尺度大于2.35 m时表现为均匀分布;而基岩风化残积土上的猪毛蒿幼苗种群在整个尺度上均呈现随机分布。（2）猪毛蒿种群幼苗在基岩风化残积土上符合泊松聚块模型,即猪毛蒿种群空间格局的聚块中不存在较高密度的小聚块;而在风沙土和灰钙土上则符合嵌套双聚块模型,即在大聚块中分布较高密度的小聚块。猪毛蒿幼苗种群空间格局的形成与土壤异质性存在着密切的联系,种群在空间中分布格局的形成机制可以通过种群空间格局的分析加以解释。     

Speciation,population structure,and demographic history of the Mojave Fringe‐toed Lizard (Uma scoparia), a species of conservation concern

The North American deserts were impacted by both Neogene plate tectonics and Quaternary climatic fluctuations, yet it remains unclear how these events influenced speciation in this region. We tested published hypotheses regarding the timing and mode of speciation, population structure, and demographic history of the Mojave Fringe‐toed Lizard (Uma scoparia), a sand dune specialist endemic to the Mojave Desert of California and Arizona. We sampled 109 individual lizards representing 22 insular dune localities, obtained DNA sequences for 14 nuclear loci, and found that U. scoparia has low genetic diversity relative to the U. notata species complex, comparable to that of chimpanzees and southern elephant seals. Analyses of genotypes using Bayesian clustering algorithms did not identify discrete populations within U. scoparia. Using isolation‐with‐migration (IM) models and a novel coalescent‐based hypothesis testing approach, we estimated that U. scoparia diverged from U. notata in the Pleistocene epoch. The likelihood ratio test and the Akaike Information Criterion consistently rejected nested speciation models that included parameters for migration and population growth of U. scoparia. We reject the Neogene vicariance hypothesis for the speciation of U. scoparia and define this species as a single evolutionarily significant unit for conservation purposes.     

沙质草地3种优势植物叶片光合生理对增温和降水减少的响应北大核心CSCD

以沙质草地优势物种猪毛蒿、胡枝子和糙隐子草为研究对象,利用开顶式生长室(OTC)模拟增温,研究降水减少20%、40%和60%与增温的交互作用对3种典型植物叶片光合气体交换特征及叶绿素荧光特征的影响,以揭示沙质草地3种优势植物对气候变化的响应规律。结果显示:(1)与自然温度相比,OTC模拟增温增加了猪毛蒿C_(i),显著降低了胡枝子G_(s)、P_(n)和T_(r)、糙隐子草G_(s)和P_(n)、猪毛蒿WUE和L_(s),也显著降低了猪毛蒿和胡枝子F_(v)/F_(m)和F_(v)/F_(o)。(2)无论增温与否,随着降水减少幅度的增加,猪毛蒿G_(s)和P_(n)呈下降趋势,且中度以上的干旱胁迫下(降水减少>40%)胡枝子和糙隐子草P_(n)显著低于对照。(3)在自然温度条件下,轻度干旱胁迫时(降水减少20%)猪毛蒿T_(r)显著低于对照,重度干旱胁迫时(降水减少60%)其WUE、F_(v)/F_(m)和F_(v)/F_(o)显著低于对照;重度干旱胁迫时,胡枝子C_(i)显著高于对照,差异幅度达10.7%,L_(s)显著低于对照,轻度干旱胁迫时(降水减少20%)其F_(v)/F_(m)和F_(v)/F_(o)显著高于中度以上的干旱胁迫;中度以上的干旱胁迫下糙隐子草T_(r)和G_(s)显著低于对照,重度干旱胁迫时,其C_(i)、F_(v)/F_(m)和F_(v)/F_(o)显著低于对照,WUE和L_(s)显著高于对照。(4)增温与降水减少交互作用下,所有处理猪毛蒿C_(i)均高于对照,差异幅度分别达4.5%,6.0%和8.4%;胡枝子T_(r)均显著低于对照,差异幅度达57.8%;重度干旱胁迫时猪毛蒿L_(s)和WUE显著低于对照,糙隐子草F_(v)/F_(m)和F_(v)/F_(o)随降水减少而降低,中度以上的干旱胁迫时其值显著低于对照。(5)相关性分析表明,3个优势物种的P_(n)与F_(v)/F_(m)和F_(v)/F_(o)均呈显著正相关关系,其中猪毛蒿和糙隐子草的P_(n)—F_(v)/F_(m)和P_(n)—F_(v)/F_(o)斜率明显高于胡枝子。研究表明,气候变暖会在一定程度上加剧降水减少对沙质草地3种群落优势物种光合作用的抑制。     

Ultrastruttura della cellula apicale di Halopteris scoparia (L.) Sauvageau (Phaeophyceae,Sphacelariales)

Abstract

Ultrastructure of the apical cell of Halopteris scoparia (L.) Sauvageau (Phaeophyceae, Sphacelariales). - The ultrastructure of resting apical cells of Halopteris scoparia (L.) Sauvageau from material collected in December is described. The cytoplasm is higly vacuolated with lipids, poliphenolic substances and polisaccharides occurring inside the vacuoles (the classic « physodes »).

Two cell organelles are prominently active at this stage: conspicuosly hypertrophic dictyosomes and the budding endoplasmic reticulum. Both light and electron microscope observations show that the cell wall has an outer stratification and inner discontinuous thickenings, the constituent material of which is uniformerly dispersed.

The above observations point out that the apical cell of Halopteris scoparia at this stage of its life cycle is engaged in an elaboration of vacuolar and parietal substances which will be therefore readly available at the outset of the growing season.     

Seasonal Differences in Photochemical Efficiency and Chlorophyll and Carotenoid Contents in Six Mediterranean Shrub Species under Field Conditions

The effects of summer and winter stress on the chlorophyll and carotenoid contents and photosystem 2 efficiency were examined in six Mediterranean scrub species. These six species belong to two different plant functional types: drought semi-deciduous (Halimium halimifolium L., Rosmarinus officinalis L., Erica scoparia L.) and evergreen sclerophylls (Juniperus phoenicea L., Pistacia lentiscus L., Myrtus communis L.). Two sites with different water availability were chosen. In the xerophytic site, despite they belong to two different functional types, R. officinalis and J. phoenicea showed a similar response. These were the most affected species in summer. H. halimifolium showed optimal values of F_v/F_m and non-significant seasonal changes in xanthophyll content. In the mesic site, E. scoparia and M. communis were apparently the most affected species by winter climatic conditions. P. lentiscus presented a pattern similar to H. halimifolium, except for elevated F₀ values. In all the studied species, lutein plus zeaxanthin content was negatively correlated with F_v/F_m in summer and with leaf water potential, thus indicating that the thermal dissipation of energy was a general pattern for all species. Under stress, plant response is more species-specific than dependent on its functional type.     

不同植物对黄顶菊根际土壤微生物和土壤养分的影响

[目的] 不同植物对外来入侵植物的抵御能力不同,研究不同植物对入侵植物根际土壤生态的影响可为筛选入侵植物的竞争替代植物提供科学依据。[方法] 利用同质园试验,以入侵植物黄顶菊为研究对象,设置黄顶菊单种、黄顶菊与不同植物（地肤、苘麻、苏丹草、反枝苋）混种处理,采用磷脂脂肪酸分析方法来研究不同植物对黄顶菊根际土壤微生物群落结构的影响,并结合土壤养分的变化探究不同植物对黄顶菊根际土壤生态的影响。[结果] 与黄顶菊单种相比,地肤和苘麻降低了黄顶菊根际微生物的总含量,改变了黄顶菊根际微生物群落结构。地肤、苘麻能竞争性抑制黄顶菊对铵态氮的吸收,从而抑制黄顶菊的生长。[结论] 不同植物的抵御能力与其土壤生态有关,替代植物通过改变黄顶菊根际土壤微生物,抑制黄顶菊对氮的吸收,从而抑制黄顶菊的生长,实现对黄顶菊的替代控制。     

Spatial heterogeneity of soil nutrients and aboveground biomass in abandoned old-fields of Loess Hilly region in Northern Shaanxi, China

The responses of soil enzyme activity of freshwater marsh, microbial biomass carbon (MBC), dissolved organic carbon (DOC) and aboveground biomass to water gradients were studied with Carex lasiocarpa pot culture experiment. The relationships between soil enzyme activity and MBC, DOC and aboveground biomass were discussed. The water gradients were W1, 15 cm; W2, ?5 cm; W3, ?5–5 cm; W4, submerged. The results indicated that acid phosphatase, invertase and urease activities were decreased with the increase of water level, while catalase activity was increased with moisture content increasing. Drying-wetting alternation (W3) increased soil enzyme activities if compared with W1. MBC content followed the order of W3 > W1 > W2 > W4, and the activities of invertase, urease and catalase were significantly positively correlated with MBC (p < 0.05). DOC content presented the order of W4 > W1 > W3 > W2, and the activities of urease and acid phosphatase were most significantly negatively correlated with DOC (p < 0.01). In addition, drying-wetting alternation promoted the growth of Carex lasiocarpa. When water submerged plants, the growth of Carex lasiocarpa was significantly inhibited. The aboveground biomass was positively related to soil enzyme activities. There were close relationships between the activities of invertase, urease and catalase and the growth situation of Carex lasiocarpa.     

Differential photosynthetic performance of three Mediterranean shrubs under grazing by domestic goats

The impact of grazing by domestic goats, Capra hircus, on the photochemical apparatus of three co-ocurring Mediterranean shrubs, Erica scoparia, Halimium halimifolium, and Myrtus communis was evaluated. Seasonal course of gas exchange, chlorophyll fluorescence and photosynthetic pigment concentrations were measured in the field in grazed and ungrazed plants. Net photosynthetic rate was higher in grazed plants of E. scoparia and H. halimifolium in May, while there were not significant differences in M. communis. Photosynthetic enhancement in grazed plants of E. scoparia could be explained largely by higher stomatal conductance. On the other hand, the lack of differences in stomatal conductance between grazed and ungrazed plants of H. halimifolium could indicate that carboxylation efficiency, and ribulose-1,5-bisphosphate (RuBP) regeneration may have been enhanced by grazing. Overall grazing has little effect on the photochemical (PSII) apparatus, however grazed plants of M. communis showed chronic photoinhibition in the short term. Finally, seasonal variations recorded on photosynthesis, photochemical efficiency and pigment concentrations may be a physiological consequence of environmental factors, such as summer drought and competition for light, rather than an adaptation to grazing.     

黄土高原先锋种猪毛蒿叶片形态解剖与生理特征对立地的适应性

为了揭示黄土丘陵沟壑区撂荒地植被演替前期优势种猪毛蒿(Artemisia scoparia)对该区立地环境的适应性,探讨猪毛蒿演替生态位的变化,研究了陕北黄土丘陵沟壑区3种立地环境下(阳峁坡、峁顶、阴峁坡)猪毛蒿叶片形态解剖和生理特征的变化,以及这些变化与生态因子之间的相互关系。结果表明:(1)猪毛蒿叶片具有适应该区半干旱环境的形态及解剖结构:叶片针形化、具表皮毛、环栅型叶肉组织、海绵组织特化为贮水组织、维管束退化、具裂生分泌腔,C3植物呈现类似CAM植物的叶片特性;(2)在土壤、空气湿度相对干燥和强光生境的阳峁坡与峁顶,猪毛蒿具有较小的叶面积、发达的栅栏组织、致密的表皮毛和紧密的细胞间隙,而在生境条件较好的阴峁坡则呈相反趋势;(3)阳峁坡猪毛蒿叶片相对含水量和叶绿素含量较小,超氧阴离子自由基增加,但植物体内超氧化物歧化酶和抗坏血酸含量增加以清除植物体内产生的活性氧;(4)冗余及相关性分析表明,猪毛蒿叶片形态、解剖和生理指标的可塑性对立地光照强度、土壤水分和有机质含量较为敏感,同时其形态解剖与生理可塑性可共同调节来适应生境。综合分析,猪毛蒿对陕北黄土丘陵沟壑区撂荒初期光照强度大、土壤贫瘠但土层干化现象尚未出现的立地环境有较好的适应性,使其成为黄土高原植被自然演替过程中的先锋物种。     

放牧践踏对黄蒿功能性状的影响

植物功能性状是构成植物个体的基础,从性状角度揭示植物个体特征的变化机制尤为重要。该研究以半干旱沙质草地优势草本植物黄蒿为研究对象,探讨不同践踏强度在生长季早期对其功能性状的影响。结果表明：(1)在群落水平上,放牧践踏显著降低了生长季早期植物群落高度;而在个体水平上,黄蒿株高不是响应放牧践踏的敏感性状。(2)黄蒿的叶长、叶宽随践踏强度增加呈先增加后减少的趋势,在中度践踏强度下达到最高;茎直径随践踏强度的增加而增加;根系和全株性状随践踏强度增加无显著差异。(3)黄蒿的叶片长度、叶片宽度、单叶面积随叶片厚度的增加而减小,且叶片与一级根数目、根茎叶生物量之间均呈显著正相关关系;放牧践踏会影响黄蒿茎直径,但对其他表型性状没有显著影响;在生长发育过程中,黄蒿通过不同表型性状的非对称变化进行性状之间的权衡,践踏强度的增加对生长季早期黄蒿根茎叶生物量积累的影响很小。研究认为,黄蒿在生长季早期对放牧践踏具有较强的抵抗力,这对生长季早期半干旱沙地放牧压力的选择和物种保护具有重要的指导意义。     

重金属Pb(Ⅱ)对3种藜科植物种子萌发的影响

以珍珠猪毛菜（Salsola passerina Bunge）、地肤（Kochia scoparia(L.)Schrad.）和白藜（Chenopodium album L.）3种藜科植物为研究对象,研究不同浓度（0、50、150、300、600、800、1 000 mg·L^-1）的Pb(Ⅱ)处理对植物种子萌发和幼苗生长的影响。结果表明：当Pb(Ⅱ)浓度为50和150 mg·L^-1时,珍珠猪毛菜和地肤种子的发芽率、发芽势和发芽指数与对照相比差异不显著,Pb(Ⅱ)浓度为150 mg·L^-1时,对白藜种子发芽率、发芽势和发芽指数有明显影响,Pb(Ⅱ)浓度大于300 mg·L^-1对3种植物种子萌发均有抑制作用,对白藜和地肤的抑制大于珍珠猪毛菜。3种植物的种子活力指数除珍珠猪毛菜在50 mg·L^-1时与对照无显著差异,其余各处理均与对照有极显著差异。Pb(Ⅱ)浓度为50 mg·L^-1时,对3种植物的胚根长和胚芽长都影响不大,随着Pb(Ⅱ)浓度的升高,对3种植物的胚根长和胚芽长都有明显的抑制作用,对地肤和白藜的抑制强度更大。地肤和白藜幼苗分别在Pb(Ⅱ)浓度为300和600 mg·L^-1时死亡,当Pb(Ⅱ)浓度达到1 000 mg·L^-1时,珍珠猪毛菜仍可生长,但生长比较缓慢。3种植物幼苗对Pb(Ⅱ)的耐受性为：珍珠猪毛菜＞白藜＞地肤。     

Response to recurrent disturbance in two co-occurring resprouter heath species: the ecological consequences of withstanding herbivores

Resprouting woody plants are vulnerable to large mammal herbivores in the early stages of regeneration after disturbance (e.g., fire, slashing), because herbivory reduces the storage of below-ground starch reserves and may thus compromise regeneration success. Defence from herbivory may incur a cost to resprouter plants in terms of lengthening the time to recovery of pre-disturbance starch levels. Erica scoparia and E. australis (Ericaceae), two resprouter woody species that co-occur in Mediterranean heath-communities of the Strait of Gibraltar, differ in the way they cope with herbivory: E. scoparia is browsing-tolerant and E. australis is a browsing-avoider. Our experimental field study demonstrated that exposure to a moderate density of ungulate herbivores markedly lowered starch re-storage after resprouting in E. scoparia, but not in E. australis. Nevertheless, time to recover pre-disturbance starch levels was shorter in the tolerant E. scoparia, even under exposure to herbivores. The slower starch recovery rate of E. australis is a likely outcome of its resource-demanding browsing-avoidance mechanism. Differences in starch recovery rates after disturbance between the two Erica species partly explains their ecological segregation at the landscape scale.     

Removal efficiency and mechanisms of formaldehyde by five species of plants in air-plant-water system

The foliar uptake and transport rates of formaldehyde as well as the abilities of leaf extracts to breakdown formaldehyde were investigated to discuss the formaldehyde removal efficiency and mechanism by five species of plants from air. Results showed that formaldehyde could be transported from air via leaves and roots to rhizosphere water. When exposed to 0.56 mg·m^?3 formaldehyde, the formaldehyde removal rate ranged from 18.64 to 38.47 μg·h^?1g^?1 FW (fresh weight). According to the mass balance in the air–plant–water system, the main mechanism of the formaldehyde loss was its breakdown in plant tissues caused by both enzymatic reaction and redox reaction. Higher oxidation potentials of the leaf-extracts of Wedelia chinensis and Desmodium motorium corresponded well to higher abilities to breakdown added formaldehyde than other plants. Based on the different abilities of fresh and boiled leaf-extracts to dissipate formaldehyde, the enzymatic reaction in Chenopodium album L. was the dominant mechanism while the redox reaction in Kochia scoparia (L.) Schrad. and Silene conoidea L. was the main formaldehyde breakdown mechanism when exposed to low-level formaldehyde in air. The redox mechanism suggested that the formaldehyde removal may be increased by an increasing level of reactive oxygen species (ROS) induced by the environmental stress.     

Enhancement of photosynthesis in post-disturbance resprouts of two co-occurring Mediterranean <Emphasis Type="Italic">Erica</Emphasis> species

The higher growth rates of resprouting shoots compared with those of mature plants in resprouter woody species are supported by higher rates of photosynthesis and transpiration. In this contribution we hypothesize that species with higher resprouting vigour will show a larger enhancement of photosynthesis in resprouting shoots. We test this hypothesis by comparing gas exchange and leaf parameters between resprouting and mature plants in Erica scoparia and E. australis. These two Erica species co-occur in Mediterranean heathlands of the Strait of Gibraltar. Erica scoparia has a higher rate of post-disturbance starch recovery than E. australis, which makes it more resistant to recurrent disturbance. We tested the hypothesis that enhancement of photosynthesis and water use characteristics of resprouting shoots compared with mature plants should be more pronounced in E. scoparia. In both species, resprouts had higher efficiency in the use of light and higher maximum net photosynthesis than mature shoots. However, contrary to expectations, differences in the photosynthetic performance between resprouts and mature plant shoots were larger in E. australis. Higher root to shoot ratios in resprouting E. australis plants, determined by their slower above-ground recovery, together with stronger demand from carbon sinks might explain this result.     

荒漠草原土壤相对湿度对猪毛蒿表型可塑性的影响

猪毛蒿(Artemisia scoparia)为菊科蒿属草本植物,是一种适应性较强的广幅种。研究荒漠草原不同土壤相对湿度条件下猪毛蒿的表型可塑性,对认识异质生境下猪毛蒿的生存适应策略具有重要的生态学意义。结果表明:株高、茎粗、根长、根重和单株生物量均表现出随土壤相对湿度的增大而增加的趋势,对异质生境具有较强的可塑性,而根冠比则表现出相对的稳定性。植株不同部位生物量大小排序为:上部中部下部,且植株下部显著大于上部生物量(P0.05)。土壤相对湿度40%生境下的头状花序数量和重量显著高于土壤相对湿度30%和30%—40%生境。繁殖器官绝对投入量(lg R)随着个体大小(lg V)的增大呈极显著的增加(P0.001),繁殖阈值介于1.868—2.006 g。随着土壤相对湿度的增加,繁殖分配比例极显著增大(P0.001)。营养器官和繁殖器官生物量、头状花序重量和数量、地下生物量和地上生物量均呈极显著线性正相关关系(P0.001),存在正向权衡。单个头状花序重量并不随个体大小和头状花序数量的增加而发生显著变化(P0.05),且在不同土壤相对湿度和不同部位间均无显著差异(P0.05)。由此可见,猪毛蒿在异质生境下产生的可塑性是其生存繁殖的重要反应机制之一。     

Evaluation of burdock and Mountain almond leaf extracts against Meloidogyne javanica on tomato

Abstract

Root-knot nematodes (Meloidogyne spp.) are one of the most harmful plant pathogenic nematodes worldwide. Application of some herbal products can safely reduce negative effect of these nematodes. In the present study, the effect of aqueous extracts of Amygdalus scoparia and Arctium lappa on hatching and mortality of second-stage juveniles of M. javanica evaluated under laboratory condition and LC₃₀, LC₅₀, LC₇₀ and LC₉₀ values were determined by probit analysis from March to November 2016. Tomato seeds (cv. Early-Urbana) were sown in 1.5?kg plastic pots and simultaneously were inoculated with 4000 eggs and second stage juveniles (J2s) of M. javanica and soil-drenched (50?ml/pot) with selected concentrations of A. scoparia viz. 0.37, 0.54, 0.8 and 1.39% and A. lappa viz. 0.51, 0.85, 1.4 and 2.91%. The experiments were carried out in completely randomized design tests with four replications. Plant growth parameters as well as nematode population indices were calculated 60?days after inoculation. Results showed that after 120?hours, leaf extracts of A. scoparia at the rate of 7.5 and 10%, and leaf extract of A. lappa at the rate of 10% lead to 100% inhibition of M. javanica egg hatching under laboratory condition. Leaf extracts of both of the tested plants at the rate of 2% caused 100% mortality of J2s. Any increase in concentration of used plant extracts significantly improved the growth indices in both of the inoculated and uninoculated tomato plants. As compared to control, application of A. scoparia leaf extract at the rate of 2%, reduced the number of galls, egg masses and eggs per root system as well as the number of J2s per pot and reproduction factor of nematode by 37, 43, 45, 73 and 46%, and in the case of A. lappa, these indices reduced by15, 26, 27, 74 and 28%, respectively. Our results showed potential of leaf extracts of A. scoparia and A. lappa for management of M. javanica infecting tomato plants.     

Effect of Seasonal and Regional Variations on Phenolic Compounds of Deverra scoparia (Flowers/Seeds) Methanolic Extract and the Evaluation of Its in Vitro Antioxidant Activity

The widespread use of Deverra scoparia Coss. & Durieu in Algerian folk‐medicine as a remedy can be relatively attributed to its total phenolic compounds. The current study aimed to provide a scientific basis for optimal collection and usage of Deverra scoparia Coss. & Durieu plant. Hence, 37 samples were gathered from nine sites in Algeria during two seasons 2016 and 2017, then exposed to a green extraction. Total phenolic (TPC), flavonoid (FC) and condensed tannins (CTC) content were estimated spectrophotometrically. The antioxidant activity was measured using five different methods, DPPH^., ABTS^.+, FRAP, CUPRAC and Fe²⁺‐chelating. The results have revealed considerable amounts of TPC varied from 804 to 1544 mg GAE/100 g dry matter, FC started from 187 up to 410 mg QE/100 g dry matter and CTC varied from 111 to 394 mg CE/100 g dry matter. The best IC₅₀ values (μg/mL) of DPPH^., ABTS^?+, FRAP, CUPRAC and Fe²⁺‐chelating tests were 56.62, 5.41, 21.26, 52.93 and 78.10, respectively. Moreover, high correlations were found between CTC and most of the antioxidant tests. Hence, CTC are suggested to be the principal group of antioxidant activity in Deverra scoparia Coss. & Durieu extracts.