警惕芒果蛎蚧Lepidosaphes tapleyi(同翅目:盾蚧科)传入中国

【背景】芒果蛎蚧属于盾蚧类昆虫,食性杂,分布广,是危害热带和亚热带水果、蔬菜和园林植物的重要害虫,主要随水果、苗木和交通工具等介质进行远距离传播。该虫被列入中华人民共和国进境植物检疫性有害生物名录。惠州口岸于2014年12月从芬兰进境的货物中截获该虫,属于我国口岸首次截获。【方法】在收集整理芒果蛎蚧的生物学、地理学等信息的基础上,介绍了芒果蛎蚧的主要形态特征、地理分布、寄主植物和生物学特性,并分析了该有害生物入侵我国的风险。【结果】芒果蛎蚧雌成虫为椭圆形,长约1.2 mm,触角每侧有1根长毛,每侧前气门有3个盘状腺,形态特征与近似种Lepidosaphes camelliae和Lepidosaphes pallida非常相似。风险分析表明,我国广东、广西、海南、云南、福建、台湾以及四川等省非常适合芒果蛎蚧生存和危害。芒果蛎蚧入侵我国会给芒果等果树造成危害,给相关产业带来损失,影响从业人员收入,还影响生态环境,可能导致生态灾难。【结论与意义】芒果蛎蚧有入侵我国的可能,加强检疫是防范该虫入侵的主要手段,生物防治是治理该虫的重要措施。     

Azione Esercitata Da Alcuni Inibitori Respiratori Sull'Inverdimento Di Apici Caulinari Di Piantine Eziolate Di Pisello

Abstract

Action of some respiratory inhibitors on the greening of apices of etiolated pea. — Aim of the research is to study the effect of some of the best kown respiratory inhibitors on the greening of etiolated apices of peas excised from the plant and kept in light in solutions containing saccharose. The inhibitors studied may act on more than one of the reactions leading to the synthesis of the chlorophyll molecule.

The following can be concluded from the present study:

1. A good level of chemical energy seems to be necessary for greening.

2. Terminal iron-oxidases seem to be necessary in this process, while a stimulating effect on greening may be attributed to an inhibition of the terminal copper-oxidases (particularly ascorbic-oxidase); the effect can be explained with the hormonal control of greening by the indoleacetic/ascorbic system.

3. Enzymes of the Krebs cycle regulate both the uptake of the essential metabolites starting from the chlorophyll molecule and the production of chemical energy.

4. Some enzymes of the glycolysis take part in some of the reactions leading to the synthesis of the chlorophyll molecule.     

海南省降香黄檀害虫种类、分布及危害症状调查

【背景】降香黄檀被确定为海南省省树后,种植面积迅速增大,但对于其病虫害的监测与防控方面的研究较少。【方法】采用人工采集结合灯光诱集的方法,调查降香黄檀种植区的害虫种类,同时对其危害症状进行了详细描述。【结果】海南降香黄檀害虫共计19种,确定了其中18种的学名,并掌握了各害虫的分类学地位、危害部位及症状。害虫在降香黄檀植株各个组织部位均有分布,其中以叶部的分布数量较大,茎干次之。苗期以食叶性害虫居多;5年生以内的植株上蛀干害虫数量显著增多;老龄植株上的茎干害虫较少。【结论与意义】海南省降香黄檀各生育期均有害虫危害,日后仍需加强对其害虫监测与防控技术的研究。     

严防外来有害生物褐纹甘蔗象入侵海南

【背景】褐纹甘蔗象原产于菲律宾,严重危害椰子等棕榈科植物和甘蔗,目前该虫已传入我国台湾、广东、广西和云南,尚未在海南省发生。【方法】为尽早预防该虫传入,本文简要描述了褐纹甘蔗象的生物生态学特性,并运用有害生物危险性分析(PRA)方法,从国内分布情况、潜在的经济危害性、受害寄主的经济重要性、传播扩散的可能性和危险性管理难度等方面对该虫入侵海南的可能性进行了定性和定量分析。【结果】褐纹甘蔗象在海南省的风险评估值R=2.08,属于高风险的林业有害生物,建议将其列入海南省林业检疫性有害生物名单;同时提出了该虫的综合防治措施和建议。【结论与意义】本研究可为尽早制定褐纹甘蔗象防范措施提供参考。     

Pugillo Di Licheni Dell'Abissinia E Dell'Eritrea

Abstract

The long pollen sequences from four volcanic lakes of the Lazio région are presented in order to outline the history of flora and vegetation on the Tyrrhenian side of Central Italy during the last hundred thousand years. The four long pollen records correlate satisfactorily with each other and reflect climatic changes at least at regional scale. Particular attention is paid to the development of arboreal vegetation during the last glacial. The local name “Lazio Complex” is given to the seven main fluctuations of trees of the Pleniglacial (from about 60,000 to about 30,000 years B.P.). The history of Zelkova, Abies, Picea, Fagus, Corylus, Ulmus, Carpinus betulus, Tilia in central Italy is outlined.     

Genetic control of Plutella xylostella in omics era

Diamondback moth, Plutella xylostella (L.), is a specialist pest on cruciferous crops of economic importance. The large‐scale use of chemical insecticides for the control of this insect pest has caused a number of challenges to agro‐ecosystems. With the advent of the omics era, genetic pest management strategies are becoming increasingly feasible and show a powerful potential for pest control. Here, we review strategies for using transgenic plants and sterile insect techniques for genetic pest management and introduce the major advances in the control of P. xylostella using a female‐specific RIDL (release of insects carrying a dominant lethal gene) strategy. Further, the advantages of gene drive developed in combination with sex determination and CRISPR/Cas9 systems are addressed, and the corresponding prospects and implementation issues are discussed. It is predictable that under the policy and regulation of professional committees, the genetic pest control strategy, especially for gene drive, will open a new avenue to sustainable pest management not only for P. xylostella but also for other insect pests.     

A review of the damage caused by invasive wild mammalian herbivores to primary production in New Zealand

ABSTRACT

Wild mammalian herbivores can compete with domestic livestock and damage other types of production systems. We reviewed damage by wild mammalian herbivores, excluding rodents, to primary production in New Zealand and assessed whether primary producers alter stocking rates in response to changes in forage availability following pest control. Given the dearth of information on the damage caused by wild mammalian herbivores to many production systems, we primarily focused on their damage to agriculture. With the exception of the substantial damage that brushtail possums (Trichosurus vulpecula) and European rabbits (Oryctolagus cuniculus) cause, there are no quantitative estimates of pasture depletion by other wild mammalian herbivores on New Zealand farmland. Estimates of dry matter consumption by wild mammalian herbivores, converted to stock unit equivalents, suggest that several species can substantially reduce stocking rates when they occur on farmland. Quantitative data on the damage they cause to horticulture and silviculture are lacking, but damage to coniferous seedlings has been recorded for possums, wallabies (Notamacropus spp.), and some species of deer (Cervus spp., Rusa spp., and Dama dama). The process that primary producers use to decide whether to control wild mammalian herbivores includes complex social and economic factors, but quantitative information is important for weighing up the expected costs and benefits of pest control. However, it is unclear how primary producers manage livestock in response to increases in forage availability following pest control. The paucity of quantitative data on wild mammalian herbivore damage to production assets is a substantial knowledge gap. Key research priorities are (i) understanding how damage varies with pest density (critical information for effective pest management) and (ii) and how primary producers alter stocking rates following reductions in pest density.     

Sulle Cause Determinanti La Formazione Di Tumori in Ibridi Di Nicotiana

Abstract

Cause of tumor formation in NICOTIANA hybrids. Further serological studies. — Additional researches have been carried out about genetical tumors in genus Nicotiana. By means of serological procedure the affinity among pairs of species that give rise to tumorous and non-tumorous hybrids has been tested, considering also their phyletic interrelation. Using ion exchange chromatography a qualitative analysis of the total proteins of tumorous and non-tumorous tissue of hybrids and of normal leaves taken from hybrids and their parental species was carried out. Serological analysis of affinity between the species tested gave following results:

1) higher serological affinity was found between species belonging to the same subgenus than between species belonging to different subgenera.

2) serological affinity between pairs of species giving rise to tumorous hybrids is higher than the affinity observed between other pairs of species that give rise to normal hybrids in spite of the same sistematic position. The same serological responses were obtained studying many species of Nicotiana with the single apparent exception of N. langsdorffii. The results of chromatographical analysis have revealed a high constancy of protein composition of the normal and tumorous tissue of hybrids. This conferms the genetical uniformity of the whole plant.     

Dactylopius opuntiae,a new prickly pear cactus pest in the Mediterranean: an overview

The Opuntia cochineal scale or false carmine cochineal scale, Dactylopius opuntiae (Cockerell) (Hemiptera: Dactylopiidae), is spreading rapidly in many countries, especially in the Mediterranean basin, where it has become a serious pest of prickly pear crops, Opuntia ficus‐indica (L.) Miller (Cactaceae). This crop is an important food resource both for humans and livestock. The cochineal was originally used as a biological agent to control cactaceous weeds in many countries where Opuntiaceae had been introduced. Currently, in some countries where the prickly pear is no longer considered a weed but a productive crop, as in the Mediterranean area, D. opuntiae has changed its role from a highly prized biological control agent to the status of serious pest. This paper provides an overview of the current knowledge on D. opuntiae for farmers and stakeholders in order to indicate the most appropriate way to limit or counteract the spread of this pest especially in new cultivated areas.     

Differenze Ultrastrutturali Di Alcune Specie Di Trebouxia Poste in Condizioni Di Illuminazione Differenti

Abstract

Ultrastructural changes in some species of « Trebouxia » under different light conditions. — Some species of the phycobiont alga Trebouxia (Tr. decolorans and Tr. albulescens), both isolated and grown on synthetic medium and still in the lichen, were examined in order to study the effect of light on the plastid ultrastructures. The species isolated from Buellia punctata and Xanthoria parietina were very sensitive to light condition and lost their chlorophyll content quickly. Striking ultrastructural changes were found in the algae grown under small light intensities and those which become achloric owing to strong light. In the latter, modifications of the Iamellar System were observed. The disappearance of Chlorophyll pigments was followed by a reduced electron density of the whole Iamellar system, as if were lacking the Iipidic compounds which are usually present and absorb fixators and dyers, thus allowing a good view. On the contrary, normal light conditions did not affect cultures of Trebouxia humicola, a free living alga. In the chloroplasts of the phycobiont species, unlike in the free living alga, grana were very close and sometimes formed very thick masses towards the edge of the chloroplast. It could not be ascertained whether such changes corresponded to a different composition of the lipoproteic compounds of the lamellar system.

Xanthoria parietina could grow in very lighted environments with no damage of the algae present in its thallus. The lichen thalluses, under different light conditions, showed very different colourings: the overlighted ones were rusty-red and the shadowed ones deep green. The chlorophyll content of the lichen thalluses with various shades (table 1) were very similar. The ultrastructural changes induced by strong light intensities in the phycobiont algae, kept in the lichen, were very small in respect of those observed in the same algae isolated and grown on synthetic medium and concerned the Iamellar system and the pyrenoid, above all. The rusty-red lichen showed a great number of stromatic lamellae, often with a parallel trend, so as to simulate a Iamellar system not organized in grana and often presented groups of lamellae concentrically arranged. In the pyrenoid of the algae from rusty-red thalluses, compared with the green ones, a much greater number of electron dense masses was observed, which are very thick and occupy the whole stromatic portion of the pyrenoid. But the Chlorophyll content did not decrease. Unlike the results of PEVELING, we noted that the electron dense masses (cited by the Author as « osmiophilic plastoglobules) were visible even after fixation with permanganate; the different numbers of these globules might depend on environmental factors. The phycobiont alga, when in the lichen thallus, could perhaps support strong light intensities, because pigments or compounds formed with the mycobiont or by it alone prevented the photooxidation of chlorophyll. Hypothetically a relationship might exist between the sensitivity of the phycobiont algae to light intensities and the content in antraquinonic pigments in the lichen thallus. But also using filters with absorption maxima similar to those of these pigments, the « in vitro » cultures of the phycobiont algae became achloric in the same time as the control ones.

Some Authors had found in Trebouxia humicola a different relationship between Chlorophyll pigments and carotinoids from that observed in the phycobiont species and had ascribed to it the greater resistence to strong light of the free living alga. Pigments or other substances present in the mycobiont can have a protective action on the Chlorophyll content and on the ultrastructures. In the phycobiont algae the resistence to strong light might be explained by an exchange of compounds between mycobiont and phycobiont, ending with the structural changes of the pyrenoid.     

Biological control: lessons from a study of California red scale

A 20-year study of suppression of California red scale, a world-wide pest of citrus, by the parasitoid Aphytis melinus has established that the interaction is dynamically stable and that the mechanisms leading to control and stability operate at a local scale: spatial processes are not important. Key features appear to be an invulnerable class in the pest and rapid development of the parasitoid compared with the pest, as well as the fact that the parasitoid is an in situ specialist on the pest. Although another parasitoid species and two predator species are also present, they play at most a negligible role in pest control. These features—long-term persistence, suppression by a single natural enemy, an invulnerable stage in the pest and rapid development in the natural enemy—appear to be common in other coccid pest systems. By contrast, in temporary crops where the pest and enemy populations are open (i.e., sustained over the long run mainly by immigration) and non-persistent locally, as is frequently found in aphid pests, we expect that multiple generalist enemies are required for control and, of course, that spatial processes are important. There are very few well-studied examples of such systems, but these support our expectations. In these cases, it also appears that neither rapid enemy development nor an invulnerable pest stage is important for successful control.     

Sul Metabolismo Dell'Alcool Etilico in Tessuti Di Fusto Di « Pisum »

Abstract

On the metabolism of ethanol in the Pea stem tissues. — The average concentration of ethanol in the growing part of the etiolated pea internodes is of the order of 10^-3M. Previous work showed that auxin at growth promoting concentration markedly lowers this level in the excised internodes. This finding prompted a series of investigations on C¹⁴ labeled ethanol utilization in this material.

The capacity of the segments to metabolize ethanol is remarkable: with an external ethanol concentration 5X10^-3M the C¹⁴ labeled CO₂ originated from 1-C¹⁴ ethanol accounted for about 10% of total CO₂ produced during the first hour of treatment. Moreover, an amount of ethanol about 10 fold higher that that dissimilated to CO₂ was metabolized to various yet unidentified compounds. The ratio between the contribution of ethanol to CO₂ and that to other metabolites appeared maximal in the first period after feeding the labeled compound. This ratio was significantly higher then that found for 6-C¹⁴ glucose.

These preliminary results suggest the possibility that ethanol produced in glycolysis could represent an interesting metabolite in an anabolic pathway different from the one leading from pyruvate to the Krebs cycle acids.     

Osservazioni Sull'Assunzione Dell'Acqua Durante le Prime Fasi Di Germinazione Di Semi Di Pinus Pinea L

Abstract

Water assumption during the early germination stages in «Pinus pinea» L. seeds. – Germination of «Pinus pinea» L. seeds in several conditions has been studied. The main results attained are the following: 1) The micropyle appears to be the only water way into the seed, to start root growth. When this route is prevented and water is absorbed only by the seed surface, the embryo grows into a big cotyledon-hypocotyl complex, where the radicle is still blocked in the embryonic stage; 2) The micropyle appears to be involved also in gas exchange processes during germination.     

Susceptibility of neonate Lissachatina fulica (Achatinidae: Mollusca) to a US strain of the nematode Phasmarhabditis hermaphrodita (Rhabditidae: Nematoda)

ABSTRACT

The nematode Phasmarhabditis hermaphrodita is a lethal parasite of many pest slug and snail species. It is used as a commercial biological control agent (Nemaslug®) in Europe but a number of key gastropod pests (e.g. Lissachatina fulica) are thought to be unsusceptible. Our data, however, demonstrated that a recently discovered U.S. strain of P. hermaphrodita causes statistically significant mortality to neonate L. fulica and consequently this nematode could be an important IPM tool for managing this snail pest in areas where P. hermaphrodita has been discovered. Soil moisture content appears to play an important role in determining nematode efficacy.     

杭州地区扶桑绵粉蚧危害调查及系统进化分析

【背景】扶桑绵粉蚧是近年来入侵我国的重要检疫性害虫,在我国多个省份均有发生,造成了严重的经济损失。【方法】于2009—2015年对杭州地区扶桑绵粉蚧的发生危害情况进行了实地调查,同时结合mt DNA COI分子标记方法,对扶桑绵粉蚧进行分子鉴定和系统进化分析。【结果】杭州市余杭区、萧山区和临安市3个地区发现扶桑绵粉蚧分布,共调查到寄主植物38科61属68种,以辣椒、茄子、番茄、南瓜、棉花、芝麻、菊花、苦荬菜、大花马齿苋和五色梅受害最严重。系统进化分析表明,杭州地区的扶桑绵粉蚧未发生明显的遗传分化,与我国其他地区扶桑绵粉蚧mt DNA COI基因相似度为99.4%~100%。【结论与意义】本研究为进一步研究扶桑绵粉蚧的遗传进化、可能的侵入途径以及科学防控提供了理论基础。     

Field efficacy of biorational insecticides against Melanaphis sacchari (Zehntner) in sorghum

Abstract

The sugarcane aphid, Melanaphis sacchari (Zehntner), is a major pest in diverse sorghum-growing regions, affecting yields if no effective control measures are implemented. The objective of this study was to evaluate the field efficacy of commercial formulations of biorational insecticides against this pest. All the evaluated biorational insecticides exerted acceptable biological efficacy for at least 7 days after application. The insecticides based on fatty acid potassium salts (Ultralux^® S and Impide^®) maintained aphid density below the established threshold of 50 aphids per leaf up to 14 days after application. The results obtained suggest that biorational insecticides can be included in the integrated management of M. sacchari.     

Alcuni Aspetti Della Variabilità Del Legno Secondario Di Un Esemplare Di Prunus Persica Stokes

Abstract

Some aspects of the variability in wood structure of a specimen of PRUNUS PERSICA Stokes. — The secondary xylem of a young stem of Prunus persica Stokes has been investigated under three main headings: 1) vessel and fibre length; 2) intrusive fibre growth; 3) relative amount of libriform fibres, fibretracheids and tracheids.

Vessel members and fibres have been reckoned from single rings and from the whole wood body.

The relation between the above mentioned dimensions and the position within the wood body and the width of the growth layers has been calculated.

No remarkable variation has been found along the axis of the stem; on the contrary there is a decrease in both fibres and vessels length along the radius of the stem from inside outwards. Such behaviour having never been recorded before, the possible causes are suggested.

A positive correlation has been found between the width of the growth layers and 1) vessel members and fibres length, 2) fibre intrusive growth, 3) percentage of libriform fibres. In addition a relative correlation between percentage of libriform fibres and age of the cambium has been put in evidence.     

Variazioni Di Composizione in Piante Di Vicia Faba L. Trattate Con Acido Gibberellico (Nota preliminare)

Abstract

The effects of gibberellic acid on the composition of VICIA FABA. — The A. takes into consideration fresh weight, dry weight, total ash and chlorophyll, carotene, mineral content variations in Vicia Faba L. plants as affected by pure and practical gibberellic acid treatments.     

AZione Della Luce Sull'Assorbimento Salino Da Parte Di Tessuti Clorofilliani In Ambiente Privo Di CO2

Abstract

Effect of light on uptake by photosynthetic tissues in the absence of co₂. — The effect of light and of CO₂ on the uptake of ⁸⁶Rb and ^-32P by isolated leaves of Elodea canadensis has been studied. The uptake of both these ions is strongly stimulated by light both in the presence and in the absence of CO₂. In the case of phosphate, light stimulates uptake and inhibits the leakage of the ion from the tissues.

These results which confirm and extend the results of other Authors, support the conclusion that the stimulation by light of active uptake of solutes by green tissues is physiologically relevant. Furthermore, they suggest that the utilization of light energy for active uptake does not depend on CO₂ fixation and assimilation.     

Biochemical and nutritional characterization of the medfly gut symbiont Enterobacter sp. AA26 for its use as probiotics in sterile insect technique applications

Background

Symbiotic bacteria contribute to a multitude of important biological functions such as nutrition and reproduction and affect multiple physiological factors like fitness and longevity in their insect hosts. The melon fly, Zeugodacus cucurbitae (Coquillett), is an important agricultural pest that affects a variety of cultivated plants belonging mostly to the Cucurbitaceae family. It is considered invasive and widespread in many parts of the world. Several approaches are currently being considered for the management of its populations including the environmentally friendly and effective sterile insect technique (SIT), as a component of an integrated pest management (IPM) strategy. In the present study, we examined the effect of diet and radiation on the bacterial symbiome of Z. cucurbitae flies with the use of Next Generation Sequencing technologies.

Results

Melon flies were reared on two diets at the larval stage, an artificial bran-based diet and on sweet gourd, which affected significantly the development of the bacterial profiles. Significant differentiation was also observed based on gender. The effect of radiation was mostly diet dependent, with irradiated melon flies reared on the bran diet exhibiting a significant reduction in species diversity and richness compared to their non-irradiated controls. Changes in the bacterial symbiome of the irradiated melon flies included a drastic reduction in the number of sequences affiliated with members of Citrobacter, Raoultella, and Enterobacteriaceae. At the same time, an increase was observed for members of Enterobacter, Providencia and Morganella. Interestingly, the irradiated male melon flies reared on sweet gourd showed a clear differentiation compared to their non-irradiated controls, namely a significant reduction in species richness and minor differences in the relative abundance for members of Enterobacter and Providencia.

Conclusions

The two diets in conjunction with the irradiation affected significantly the formation of the bacterial symbiome. Melon flies reared on the bran-based artificial diet displayed significant changes in the bacterial symbiome upon irradiation, in all aspects, including species richness, diversity and composition. When reared on sweet gourd, significant changes occurred to male samples due to radiation, only in terms of species richness.