A report on the conservation status of segetal weeds in Tajikistan

Intensification of agriculture has significantly diminished the populations of segetal weeds worldwide in recent decades. Remarkable changes to the entire flora and vegetation of man‐made habitats are being observed in agroecosystems. The present study analyses, for the first time, the threat status of segetal weeds in Tajikistan. A group of 871 weed species were evaluated against IUCN criteria. The assessment of threat status revealed that 214 weed taxa have to be regarded as threatened in Tajikistan, including 18 endemic and four subendemic plants. Five species have been classified as extinct, 27 as critically endangered, 27 as endangered, 39 as vulnerable, 34 as near threatened and 44 as in the ‘least concern’ category. For 38 species, the threat level was not possible, due to lack of data. The most threatened group of taxa is related to rice paddy fields. Numerous losses and disappearances were also observed in cereal communities. Percentages of threatened species in different chorological groups amounted to 58% in the Irano–Turanian, 17% in the Pluriregional, 11% in the Mediterranean, 9.5% in the Cosmopolitan and 4% in the Euro–Siberian species group. Assessment of the threatened status of the rich segetal flora of Tajikistan affords the opportunity to raise awareness of the value of this group of species in the country and may be useful in the conservation management of arable habitats. The results show that even though agriculture in Tajikistan is still based on traditional management and manual work, weed control causes a serious threat to its segetal flora.     

Investigation of threatened arable weeds and their conservation status in Turkey

Agronomic operations carried out in arable lands may cause changes in weed populations and also decrease the number of animal species that depend on these weed species. An emerging paradigm is the conservation and sustainability of weed species. In this study, risk status of arable weeds in Turkey was evaluated and it was determined that 112 of them (76 endemic and 36 non-endemic species) were at risk according to the IUCN Red List. Turkey is extremely diverse, with over 3000 endemic plant species out of nearly 12 000 recorded. Considering endemic weeds, they are classified in the following risk categories: critically endangered (four weed species), endangered (EN) (six), vulnerable (VU) (14), near threatened (seven), least concern (41) and data deficient (DD) (four species). Among the non-endemic weeds, three species are EN, 31 VU and two are DD. The families with the highest threatened weed species are Scrophulariaceae, Fabaceae, Asteraceae, Brassicaceae and Lamiaceae. The identification of weed species in arable habitats and their risk status is a useful tool for assessing and monitoring how the sustainability of weed populations is affected by farming practices. The results show the necessity of adopting new environment-friendly agricultural methods to conserve the high number of endemic weed species under threat in Turkey.     

基于GIS的三江源地区物种多样性保护优先性分析

根据我们的多次科考调查和青海省对野生动物的调查结果等有关资料图件,对三江源地区的物种多样性和人类干扰因素等进行了分析和评估。选择9种鸟类、15种哺乳动物、20种植物作为本研究的指示物种,利用GIS制作了主要的珍稀濒危野生动植物分布图。选择放牧、人口、居民点、公路等因素作为生物多样性的主要干扰因素,制作出三江源地区干扰强度空间分布图。然后根据物种的丰富度和特有性、脆弱性和干扰程度等指标分析了三江源地区物种多样性保护优先性地区,做出了物种多样性保护优先地区空间分布图。     

Plant assemblage and diversity variation with human disturbances in coastal habitats of the western Arabian Gulf

Knowledge about plant diversity along disturbance gradients is essential for conservation and management of fragmented coastal habitats.This study examined the effects of human disturbance intensity in coastal habitats of Kuwait on diversity,composition,identity and assemblage of vascular plant species.Plant survey data from 113 plots (5m×5m each) were randomly selected in 51 sites at coastal fragmented habitats at three levels of disturbance intensities (high,moderate and low) and were statistically analyzed.The results revealed that about 76% of the recorded species are considered threatened species in Kuwait,most of which are being lost in high disturbed habitats.Disturbance led to the dominance of Zygophyllum qatarense,Cornulaca aucheri and Salsola imbricata,which are species of disturbance indicators.Richness,total plant cover and species diversity were higher in moderate and low disturbed habitats than in high disturbed habitats.Beta diversity between high and low disturbed habitats was higher than either between high and moderate,or between moderate and low disturbed habitats.Cluster analyses showed statistically significant differences in composition of plant assemblages,which indicate high beta diversity between the habitat types.Intensive urbanization and industrialization are among the most serious threats that contribute to declines in biological diversity and rapid fragmentation of coastal habitats in Kuwait.Establishing protective enclosures in the disturbed habitats,planting endangered and vulnerable species,and establishing a natural reserve at Nuwaiseeb are recommended conservation actions to avoid loss of the fragmented coastal habitats and to facilitate restoration of native plants.     

Response of selected South Australian native plant species to Phytophthora cinnamomi

Thirty‐seven South Australian native plant species from 11 families, including 15 threatened species in the state (of which six are listed as threatened under the federal Environment Protection and Biodiversity Conservation Act 1999) were assessed for response to infection by Phytophthora cinnamomi. Seedlings, 3–6 months old and grown in a greenhouse, were inoculated by placing infested pine wood plugs in the potting mix, maintained in moist conditions and assessed for mortality and disease symptoms for between 3 and 10 months. Thirty species were found to be susceptible, of which nine were highly susceptible, 15 moderately susceptible and six slightly susceptible. Three species were found to be resistant and results for four species were inconclusive. Six of the 15 threatened, rare or locally endangered species tested (Eucalyptus viminalis var. viminalis, Correa aemula, C. calycina, Olearia pannosa ssp. pannosa, Pomaderris halmaturina ssp. halmaturina and Prostanthera eurybioides) were moderately susceptible, while two (Allocasuarina robusta and Pultenaea graveolens) were highly susceptible. Significant populations of at least five of the threatened species susceptible to the disease are located close to confirmed or suspected Phytophthora‐infested areas or growing in areas conducive for P. cinnamomi. An effective management strategy is therefore required to avoid extinction of such species due to infection by the phytophthora dieback pathogen.     

Reviewing change in the arable flora of Europe: a meta‐analysis

Changing agricultural practices have dramatically altered the arable flora of Europe since the Second World War. We conducted a meta‐analysis of the available literature to assess the dynamics of species richness and species traits in the arable flora across Europe during this time period. We found a total of 32 publications, yielding 53 data sets with an average number of 252 studied plots per data set. Average species number per plot of arable plants across all data sets declined by about 20%. However, twelve data sets showed an increase in average species number per plot, including all studies starting after 1980. Plant species preferring nutrient‐rich sites, neophytes and monocotyledons generally increased since 1980, while characteristic or threatened species of arable weed communities further declined. This temporal development of the European arable flora suggests that the changes happening in agricultural management since the 1980s, such as organic farming and reduced pesticide input, may have helped slow the decline of the arable flora in terms of species number, but not in terms of characteristic or threatened arable weeds. Hence, more specific measures are necessary to stop decline of the latter, making sure that these measures are advantageous for rare and characteristic arable species, but not for harmful weeds.     

Mapping the current and future distributions of Onosma species endemic to Iran

Climate change may cause shifts in the natural range of species especially for those that are geographically restricted and/or endemic species. In this study, the spatial distribution of five endemic and threatened species belonging to the genus Onosma (including O. asperrima, O. bisotunensis, O. kotschyi, O. platyphylla, and O. straussii) was investigated under present and future climate change scenarios: RCP2.6 (RCP, representative concentration pathway; optimistic scenario) and RCP8.5 (pessimistic scenario) for the years 2050 and 2080 in Iran. Analysis was conducted using the maximum entropy (MaxEnt) model to provide a basis for the protection and conservation of these species. Seven environmental variables including aspect, depth of soil, silt content, slope, annual precipitation, minimum temperature of the coldest month, and annual temperature range were used as main predictors in this study. The model output for the potential habitat suitability of the studied species showed acceptable performance for all species (i.e., the area under the curve (AUC)>0.800). According to the models generated by MaxEnt, the potential current patterns of the species were consistent with the observed areas of distributions. The projected climate maps under optimistic and pessimistic scenarios (RCP2.6 and RCP8.5, respectively) of 2050 and 2080 resulted in reductions and expansions as well as positive range changes for all species in comparison to their current predicted distributions. Among all species, O. bisotunensis showed the most significant and highest increase under the pessimistic scenario of 2050 and 2080. Finally, the results of this study revealed that the studied plant species have shown an acute adaptability to environmental changes. The results can provide useful information to managers to apply appropriate strategies for the management and conservation of these valuable Iranian medicinal and threatened plant species in the future.     

新疆北塔山地区珍稀濒危植物种类及其地理成分

北塔山为中蒙边境的界山,地处新疆境内,属典型干旱山区,植物种类贫乏,区内珍稀濒危植物共计21种,隶属16科16属。其中,国家重点保护野生植物8种,中国物种红色名录收录6种,新疆重点保护野生植物15种;珍稀濒危种子植物区系分布区类型以北温带成分为主,与地中海、西亚至中亚分布及其变型联系紧密,中亚分布类型有微弱渗入;珍稀濒危种水平分布西多东少,集中分布于海拔900~2 000 m,且以旱生灌木、半灌木为主,仅有少量中生和湿生植物。     

Enhancing the effectiveness of biological control programs of invasive species through a more comprehensive pest management approach

Invasive species are one of the greatest economic and ecological threats to agriculture and natural areas in the US and the world. Among the available management tools, biological control provides one of the most economical and long‐term effective strategies for managing widespread and damaging invasive species populations of nearly all taxa. However, integrating biological control programs in a more complete integrated pest management approach that utilizes increased information and communication, post‐release monitoring, adaptive management practices, long‐term stewardship strategies, and new and innovative ecological and genetic technologies can greatly improve the effectiveness of biological control. In addition, expanding partnerships among relevant national, regional, and local agencies, as well as academic scientists and land managers, offers far greater opportunities for long‐term success in the suppression of established invasive species. In this paper we direct our recommendations to federal agencies that oversee, fund, conduct research, and develop classical biological control programs for invasive species. By incorporating these recommendations into adaptive management strategies, private and public land managers will have far greater opportunities for long‐term success in suppression of established invasive species. © 2016 Society of Chemical Industry     

Impact of site conditions and farming practices on the occurrence of rare and endangered weeds on arable land in the Czech Republic

This article documents the impact of site conditions and farming practices on the occurrence of rare and endangered weeds on arable land in the Czech Republic. A survey was conducted between 2006 and 2008 in winter cereals, spring cereals and wide‐row crops. The relationship between the occurrence of plants and explanatory factors was analysed using a multivariate analysis to calculate species frequencies in different types of farming, crops and altitudes. In total, 290 relevés were recorded, with a total number of 172 weed species. Nineteen weeds, classified as rare and endangered species according to the national Czech list, were identified in 106 relevés. The highest effect on the occurrence of rare and endangered weed species was observed for altitude. Almost half of the recorded endangered and rare species belonged to the thermophilous weed vegetation typical for cereals on basic soils. A higher occurrence of endangered species has been confirmed for organic farming, where the sum of frequencies was 4.5 times higher than in conventional farming. Field size was not included in our analyses, but could be a factor affecting weed assemblages. The highest frequency of rare species was recorded in spring cereals, followed by winter cereals and wide‐row crops. Higher numbers were identified within fields with higher weed coverage. Lower farming intensity and diversified farming systems at higher altitudes provided better conditions for the occurrence of rare species than intensively farmed lowlands.     

Development of lowland weed management and weed succession in Japan

Since the introduction of rice production in Japan, lowland areas have been managed for rice production with the purpose of better rice growth, as well as lesser weed infestation. Rice is cropped every year in lowland fields by repeated cultivation of a single crop, with high yields and without soil sickness usually being observed in upland fields. This is probably because the irrigation water supplies various nutrients for healthy rice growth and the drainage washes out and removes harmful factors. However, until recently, the wet or flooded conditions of lowland fields in the Asian monsoon region never have allowed humans to cultivate useful summer crops, except rice or some aquatic plants. Therefore, the management of lowland areas in the Asian monsoon region has been significantly different from European field management, where crop rotation has been the traditional standard practice. Paddy weeds are aquatic plants or hygrophytes that have adapted to lowland fields. Traditionally, tillage and puddling were practiced seasonally in lowland fields on a regular schedule every year. Rice cultivation technology was developed and supported by regional irrigation systems that created stable environments for typical paddy weeds to complete their life cycle. After the introduction of chemical weed control, rice fields became very severe habitats for these paddy weeds, where they could not grow and reproduce without strategies for survival under herbicide exposure. Even so, many of the traditional paddy weeds survived because of their accumulated or uneradicated seed banks, although several aquatic plants were listed as endangered or threatened species. The important weed species changed, sometimes rapidly and sometimes slowly, depending both on their reproductive system and their biological response towards field management and weed control systems. Very recently, the level of perennial weeds, herbicide‐resistant weeds, and weedy rice has increased in paddy fields that are highly dependent on herbicide use. In addition, several hygrophyte species have invaded paddy fields. In order to address these issues, the improvement and application of integrated weed management methods are expected to be critical.     

Killing two bugs with one stone: a perspective for targeting multiple pest species by incorporating reproductive interference into sterile insect technique

The sterile insect technique is an environmentally friendly method to control and even eradicate agricultural and veterinary insect pests without using chemical pesticides in excess. However, the continuous production and release of sterile insects is economically costly and eradication programs using sterile insects have not always been successful owing to the incomplete mating ability of the sterile insects. Here we focus on the theory and empirical findings of interspecific negative mating interaction, known as reproductive interference, to develop a more cost‐effective and value‐added pest management program. We suggest that sterile insects can be used for simultaneous control of both wild‐type conspecifics and closely related pest species by taking advantage of the fact that, when species recognition abilities are incomplete, courtship and mating are often misdirected toward heterospecies. This new approach might help mitigate economic damage and human health crises caused by pest insects. © 2018 Society of Chemical Industry     

Chemical control of the invasive Jackson's chameleon (Trioceros jacksonii xantholophus) in Hawaii

Invasive reptiles cause global ecosystem damage and are difficult to control once established. Visual detection and manual capture are time consuming and largely ineffective at eradication, particularly for cryptic species. The Jackson's chameleon (Trioceros jacksonii xantholophus), native to eastern Africa, is popular in the global pet trade and has become established in several localities, including the Hawaiian Islands where it has escaped or been intentionally released into sensitive native forest habitat where it feeds on endangered species. Here we tested an orally delivered, chemical toxicant as a feasible management technique for this invasive lizard in Hawaii. We administered predetermined dosages of powdered acetaminophen to adult chamleoens and determined that the dosage necessary to achieve ≥95% mortality within 48 h across size classes was 2000 mg/kg, or 90 mg of acetaminophen for an adult average mass of 45 g. Since the liver is known to process acetaminophen in vertebrate taxa, we conducted post mortem histological examination of liver tissue for all specimens at the 48 h time point. Finally, we propose a testable mechanism for field delivery of this oral toxicant following behavioral trials.     

Managing outbreaks of invasive species: Eradication versus suppression

Abstract

A framework is developed to evaluate eradication as one of three alternative management responses to an outbreak of an invasive species: eradication, suppression or no action. This framework can be used to establish under what conditions an eradication option could provide an expected net economic benefit, and whether this net benefit exceeds that of the other two options. The eradication option is more likely to be preferred in situations where there is an immediate export benefit that is derived from eradication of the outbreak, and also the uncertainty associated with the likely success of eradication is low.     

外来入侵植物病毒在我国的发生、危害与管理

外来入侵植物病毒已经严重威胁全球多个国家和地区的农业生产。预防和控制入侵植物病毒能够确保农业安全生产和可持续发展。本文详细地总结与综述了我国重要外来入侵植物病毒发生与危害情况。结合国内外生物入侵防治经验与我国入侵植物病毒的实际情况,分析了我国植物病毒入侵防控面临的挑战,提出了我国入侵植物病毒防控的几种通用措施。     

内蒙古西部自然保护区生态环境保护可持续发展——以西鄂尔多斯保护区为例

恶劣的自然地理环境条件使得内蒙古西部自然保护区生态环境保护十分困难，而人类活动，特别是地区经济、城市工业等的发展又成为目前造成保护区生态环境恶化的直接原因，西鄂尔多斯自然保护区就是一典型例证。     

Endemics and endangered species in the biodiversity hotspot of the Shada Mountains,Saudi Arabia

Shada Mountains in Saudi Arabia, separated by Maleel Wadi into twin mountains(i.e., Shada Alalah and Shada Asfal), are rich in biodiversity. We investigated the diversity of endemics and endangered species of the mountains based on the data collected from 38 stands falling in 8 elevational zones ranging from 500 to 2215 m a.s.l. Results indicated that 495 plant species falling in 314 genera and 76 families occurred in the Shada Mountains, including 19 endemic species and 43 endangered species, and accounting for 22% of the total flora in Saudi Arabia. Canonical correlation analysis indicated that physiographic features, particularly altitude play an important role in the frequency and abundance of species. Endemics were not evenly distributed in the Shada Mountains and mostly restricted in the elevation zone of 1000–1500 or 1500 m a.s.l. When the altitude reached up to 2000 m a.s.l., the endemics decreased substantially due to the significantly low temperature. The endangered species existed three different distribution patterns:(i) most endangered species distributed in the altitudes of 1000–1800 m a.s.l.;(ii) endangered trees, lianas, and shrubs occupied the altitudes 1000–1300 m a.s.l.; and(iii) endangered subshrubs and herbs inhabited the altitudes 1500–2100 m a.s.l. The results demonstrated that the biodiversity of endangered species in the Shada Mountains is high and undisturbed by invasive species, and protective measures should be taken against human disturbances to the small-scale hotspot.     

草地贪夜蛾对云南德宏玉米经济损失评估及防治措施调查

草地贪夜蛾Spodoptera frugiperda自2019年1月入侵我国云南以来,快速蔓延为害,严重威胁我国的玉米生产和粮食安全。本研究基于云南省德宏州351份玉米农户调查数据,利用以直接经济损失和防治费用为基础的经济损失评估模型,估算了2019年草地贪夜蛾对德宏州玉米生产造成的经济损失,并分析了农户实际采用的防治措施。结果表明,2019年草地贪夜蛾对德宏州玉米生产造成的经济损失约为1 399.29万元,其中,玉米产量变化造成的直接经济损失约为366.51万元,农户防治投入增加和政府宣传、培训和防治等费用支出约为1 032.78万元。本研究不但为了解草地贪夜蛾对我国不同地区作物生产造成的经济损失提供例证,也为因地制宜地制定草地贪夜蛾防治策略提供科学依据。     

Real-time PCR,a great tool for fast identification,sensitive detection and quantification of important plant-parasitic nematodes

Plant-parasitic nematodes can cause significant damage to agricultural crops and forests worldwide, resulting in major economic losses. Some nematode species do not occur in all areas and are regulated as quarantine organisms. To avoid introduction and spread of these organisms, fast, simple and reliable detection and identification methods are needed, that help plant diagnostic services such as reference centres or national plant protection organizations (NPPOs) to rapidly identify suspicious nematodes. Real-time PCR is one of the fastest, most sensitive and reliable methods to fulfil this task. It is a DNA-based method that is easy to learn with the only requirement of having a specific thermocycler (Real-time Platform) and the appropriate chemistry. Real-time PCR provides very sensitive detection and species-specific identification with the potential to quantify target organisms if required. Following DNA extraction, results can be seen in 1–3 h and management decisions applied. Real-time PCR can be used for high-throughput analysis of many samples and in some cases for multiplexing, allowing for identification of more than one species in a single reaction. Over the past 15 years, real-time PCR methods have been developed for the main plant-parasitic nematodes, in particular the regulated species. This paper reviews the achievements in plant nematology diagnostics using real-time PCR as the method of choice for fast and reliable detection, identification and even quantification of plant parasitic nematodes.     

Understanding growers' decisions to manage invasive pathogens at the farm level

Globalization causes plant production systems to be increasingly threatened by invasive pests and pathogens. Much research is devoted to support management of these risks. Yet, the role of growers' perceptions and behavior in risk management has remained insufficiently analyzed. This article aims to fill this gap by addressing risk management of invasive pathogens from a sociopsychological perspective. An analytical framework based on the Theory of Planned Behavior was used to explain growers' decisions on voluntary risk management measures. Survey information from 303 Dutch horticultural growers was statistically analyzed, including regression and cluster analysis. It appeared that growers were generally willing to apply risk management measures, and that poor risk management was mainly due to perceived barriers, such as high costs and doubts regarding efficacy of management measures. The management measures applied varied considerably among growers, depending on production sector and farm-specific circumstances. Growers' risk perception was found to play a role in their risk management, although the causal relation remained unclear. These results underscore the need to apply a holistic perspective to farm level management of invasive pathogen risk, considering the entire package of management measures and accounting for sector- and farm-specific circumstances. Moreover, they demonstrate that invasive pathogen risk management can benefit from a multidisciplinary approach that incorporates growers' perceptions and behavior.