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1.
The olive is one of the most important crops in Greece as in many Mediterranean countries. Several insects are considered serious pests of the olive crop. In this study, we report two new pests for olive trees in Greece and possibly in the Mediterranean region: the quince moth Euzophera bigella (Zeller) (Lepidoptera: Pyralidae) and the olive leaf gall midge Dasineura oleae (F. Low) (Diptera: Cecidomyiidae). Although E. bigella is not considered a pest of olive trees, in the summer of 2011, the quince moth was recorded for the first time infesting olive trees in several orchards in the rural area of the Municipality of Amphipolis (Region of Central Macedonia). Infestation induced cracking and swelling symptoms on the bark of limbs and the periderm of trunks, accompanied by extensive internal bark necrosis, which caused the desiccation of limbs or even the death of whole trees. D. oleae has been reported infesting olive trees in Greece; however, it was not considered a pest of the crop. In February 2010, extensive infestations by D. oleae were detected in the coastal zone of Elounda, Lassithi (Region of Crete). Infestations were observed on the leaves causing elongate galls and deformations, while in highly infested trees defoliation was reported. Because of the scarceness of these infestations, the results reported in this study are discussed in relation to cases reported from other countries and/or on other crops. In addition, a review of the distribution, biology and control methods of these species is provided in an attempt to summarize the scattered information currently available.  相似文献   

2.
Psyttalia concolor (Szépligeti) (Hymenoptera: Braconidae) is a koinobiont larval–pupal endoparasitoid of a large number of tephritids. P. concolor can be commonly reared on fully grown Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) larvae. In our laboratory, over 180 consecutive generations have been completed on C. capitata. In this study, we tested the possibility that the uninterrupted mass-rearing of P. concolor on C. capitata may influence its host location and parasitisation behaviours when used against Bactrocera oleae (Rossi) (Diptera: Tephritidae), the fruit fly commonly targeted in mass release of P. concolor in olive-groves. Choice and no-choice tests were used with naïve and experienced P. concolor females exposed to B. oleae and/or C. capitata larvae. The study showed no significant difference in oviposition behaviours and host acceptance when provided either C. capitata or B. oleae. However, the study did show that experience on a host plus a substrate complex could influence host preferences, since females that had previous oviposition experience on a given host species searched and chose significantly more when the same host species was presented, both in choice and no-choice conditions. Therefore, within the context of the pest management of fruit flies, it could be very useful to incorporate procedures in insectary-propagated fruit fly parasitoids designed to provide adequate training (i.e. oviposition experience) on the fruit fly species needing to be controlled.  相似文献   

3.
1998年 8月   国务院发出紧急通知   要求保护森林资源制止毁林开垦和乱占林地通知提出了七项具体要求, 1、要把保护和培育森林资源作为改善生态环境的重要任务来抓。 2、立即停止一切毁林开垦行为。 3、对已经发生的毁林开垦行为进行全面清查。 4、切实做好退耕还林工作。 5、依法严厉打击毁林开垦的违法犯罪行为。 6、严格实施林地用途管制。 7、加强对林地保护工作的组织领导。   1999年 1月 7日   国务院发布全国生态环境建设规划确定到 2003年,新增治理水土流失面积 30万平方公里,治理荒漠化土地面积 960万公顷;新增森林面…  相似文献   

4.
The purpose of this study is to investigate the biology of Cryphalus piceae (Ratz.) (Col., Scolytidae) living in Abies bornmülleriana (Mattf.) in fir forests in the Western Black Sea region in Turkey. The dates of swarming, tree attack, egg-laying, and different stages of development are given. The species had two generations per year.  相似文献   

5.
For the biological control Bemisia tabaci (Genn.) Biotype B (Homoptera: Aleyrodidae) , about 200,700 individuals of the imported parasitoid Eretmocerus hayati Zolnerowich and Rose (Hymenoptera: Aphelinidae) were released during 2000 and 2002 on different host plants in Egypt. The average parasitism rates in different governorates on Lantana camara, Gossypium barbadence (cotton), Helianthus annus (soybean) and Solanum melongena (eggplant) were 10.3 and 14%, 16 and 11.4%, 12.9 and 8.7%, 18 and 13% during 2001 and 2002, respectively. The population of E. hayati correlated significantly with the buildup of the whitefly population in all three governorates, which indicated the establishment of the E. hayati parasitoid on these economically important crops in Egypt.  相似文献   

6.
The red flour beetle, Tribolium castaneum (Herbst), is one of the most serious secondary pests that feeds on a wide range of durable stored products including cereals, cereal products and other high value produce such as cocoa beans and dried fruits. Toxicity and protectant potential of Calneem® oil derived from the seeds of the neem tree Azadirachta indica A. Juss. towards T. castaneum were evaluated in stored wheat in the laboratory using contact toxicity, grain treatment, persistency, progeny emergence and repellency assays. Calneem® contains about 0.3% azadirachtin as its major active ingredient. The Calneem® was applied at six dosages (0.1, 0.2, 0.5, 1.0, 2.0 and 3.0% v/v). The oil was emulsified with water using 0.07% soap. All dosages of Calneem® oil were toxic and highly repellent to T. castaneum with an overall repellency in the range of 52–88%. The highest dosage of 3.0% of Calneem® oil tested killed at least 90% of the beetles within 72 h on grain, and 88% mortality was obtained on filter paper. T. castaneum mortality was dose dependent. The development of eggs to adults on cracked wheat was significantly (P < 0.05) inhibited by Calneem® oil treatments. The effectiveness of Calneem® oil was significantly reduced by the length of storage after application. The results obtained suggest good potential for the practical use of Calneem® oil as grain protectant for stored product pest control. The use of plant materials such as neem oil may be a safe, cost-effective method of grain preservation against pest infestation amongst low-resource poor farmers who store small amounts of grains.  相似文献   

7.
The study investigated the development, survivorship, and food intake of cotton leafworm Alabama argillacea (Hübner) fed on three cotton cultivars with colored fibers. Significantly shorter larval life-span and higher pupal weight as well as higher survival rates were observed in A. argillacea fed on leaves of BRS Safira and BRS Rubí cotton cultivars compared with the BRS 200 cultivar (BRS = Brazil). Weight gain, feces, and food intake were higher in A. argillacea fed on leaves of BRS Safira compared with the BRS 200 cultivar. The cotton cultivar significantly affected all larval food intake and utilization indices for A. argillacea. The larvae of A. argillacea were more efficient (higher efficiency in converting ingested (ECI) and digested (ECD) food) when fed on leaves of the BRS Safira cultivar in comparison to the BRS 200 cultivar, since the larval phase was shortened and food intake was higher, resulting in a higher growth rate (RGR). However, A. argillacea larvae fed on the leaves of the BRS 200 cultivar, with lower ECI and ECD, exhibited a compensatory response, extending the duration of the larval phase and increasing food intake, resulting in a higher relative metabolic rate. We conclude that BRS Safira provides the best food quality for A. argillacea, BRS 200 the worst, and BRS Rubi plants of intermediate quality.  相似文献   

8.
The main purpose of this study was to establish whether sugi lumber with an extremely low Young’s modulus, which is plentifully produced in southern Japan, can be practically used as laminae for glued laminated timber (glulam) from the viewpoint of long-term performance under loading. Bending creep tests were carried out on sugi (Cryptomeria japonica D. Don) glulam with extremely low Young’s modulus laminae (3–4 kN/mm2) for the inner layers, as were tests on hybrid glulam with Douglas-fir (Pseudotsuga menziesii Franco) laminae (14–15 kN/mm2) for the outermost layer and sugi laminae (including those with a Young’s modulus of 3–4 kN/mm2) for the inner layers. The specimens were eight glulam beams with different compositions that were 105 mm wide, 210 mm deep, and 3980 mm long. The term of the creep test was 4 years. The results are summarized as follows. First, there were no significant differences between the Young’s modulus or bending creep of glulam L30 (laminae with Young’s modulus of 3–4 kN/mm2) and that of glulam L50 (laminae with Young’s modulus of 5–6 kN/mm2) for the inner layers. Second, for asymmetric compositions, the behavior of increases and decreases of relative creep due to atmospheric changes showed opposite behavior for glulam loaded from the side of lower Young’s modulus and from the side of higher Young’s modulus. Third, the required experimental term for the creep test to estimate an accurate long-term curve is 1 or 2 years (with data for the first 6 months excluded) when the power law is used for the estimation. Fourth, the values of relative creep in 50 years obtained from the experimental term were much lower than 2, which is the standard value set by Notification No. 1459 of the Ministry of Construction in Japan, and these values were not affected by the composition of the laminae.  相似文献   

9.
The effect of various host plants; chickpea (varieties Arman, Hashem, Azad and Binivich), bean varieties (Phaseolus vulgaris L.), common bean (Khomein), white kidney bean (Dehghan), red kidney bean (Goli), cowpea (variety Mashhad) and tomato (variety Meshkin) on the life table parameters of the cotton bollworm, Helicoverpa armigera (Hübner) were evaluated under laboratory conditions (25 ± 1 °C, 65 ± 5 % RH and a 16:8 h light:dark photoperiod). Records for larval period, pupal period, and development time of H. armigera were longest on tomato (24.9, 15.1, and 45.4 days, respectively) and shortest on chickpea Arman (17.5, 9.1, and 31.7 days, respectively). Among various host plants fecundity (total number of eggs laid per female) was highest (2,665 eggs) on chickpea Arman and the lowest (700 eggs) on tomato. The net reproductive rate (R 0) was significantly affected by various host plants being highest on chickpea Arman (1,422) and lowest on tomato (111.3 females/female/generation). The highest and lowest intrinsic rates of natural increase (r m) were observed on chickpea Arman (0.244 day?1) and tomato (0.123 day?1) varieties, respectively. Cluster analysis of the life table parameters of H. armigera on various host plants indicated that tomato, in comparison to other plants was an unsuitable host to H. armigera.  相似文献   

10.
Abstract The biology of two important lepidopterous pests, Prays oleae Bernard and Palpita unionalis Hübner, was studied. The target pests were reared on olive plants, Oleae europaea L. (Oleaceae) under laboratory conditions for two successive generations, from March to June 2002. For P. oleae, the duration of larval stage development in the first generation was 21.4 ± 0.18 days at 19.3–20.9 °C, 65–68 % R.H, while in the second generation it was 14.8 ± 0.10 days at 20.8–24.2 °C, 65–69 % R.H. The number of eggs laid per female ranged from 58 to 109 eggs in the first generation, and from 47 to 113 in the second. The larval stage duration of P. unionalis was 16.3 ± 0.12 days at 16.8–22.9 °C, 65–69 % R.H. and 15.5 ± 0.12 days at 21.6–25.5 °C, 66–69 % R.H. for the first and second generations, respectively. Also, the number of eggs laid per female ranged from 630 to 653 eggs, and from 425 to 493 eggs in the second generation under the same previous laboratory conditions. P. oleae laid eggs at night mostly singly on flower-buds, more on the calyx. than on the petals. The larvae mined on leaves and damaged groups of flowers. P. unionalis adults were active at night, laid eggs singly at twilight usually on the lower surface of foliage. Larvae fed on leaves spinning several leaves together to form shelter for the pupa.  相似文献   

11.

Introduction   

We examined the functional relationship between seed size and seedling performance in the valley oak (Quercus lobata Née) by means of a 13-year common garden experiment.  相似文献   

12.
ThemiteofthegenusLeptusisworld-widedistributedandectoparasitedoninsectsandonspiders.InJapan,ninespeciesofthisgenushavebeenrec...  相似文献   

13.
Conserving saproxylic beetles in temperate forests will require a better understanding of habitat requirements. So far, quantitative community studies have rarely considered their vertical requirements. In comparison with the tropical forest canopy, it remains to be seen whether a comparably high level of beetle diversity exists in the temperate forest canopy.We compared saproxylic beetle assemblages at two vertical levels in three temperate French forests. Two datasets originated from emergence traps of pine and oak deadwood substrates (mid-canopy and forest floor branches) in lowland forests. The third compared flying beetle fauna at mid-canopy and understory levels using pairs of flight interception traps in beech-fir mountain forests.Our study provided contrasting results regarding the contribution of each stratum to biodiversity. Whereas higher abundance and species richness were apparent in understory samples in beech-fir stands and in oak branches, no difference for richness - or even the opposite pattern for abundance - was observed in pine branches. A significant inter-strata dissimilarity was revealed in all datasets. Each stratum harbored specialist taxa. Exclusive canopy species accounted for 20-40% of all species. In accordance with dissimilarity partitioning, arboreal saproxylic beetle communities were not just nested subsets of ground assemblages.It is likely that microhabitat requirements, food availability and other non-resource-based factors (microclimate preference, species interactions) drive the stratification of beetle assemblages.Our results lend support (i) to the recommendation of a multi-strata sampling strategy for forest insects and (ii) to management practices in favour of valuable canopy micro-habitats.  相似文献   

14.
第五章 防治病害虫害第三十二条 国家、集体所有的森林和个人所有的林木应当积极防治病害、虫害。在发生毁灭性的病害、虫害的时候,当地县、乡人民委员会必须立即组织力量,进行抢治。  相似文献   

15.
Proteinase inhibitors are currently targeted as potential insect control agents, but adaptation to proteinase inhibitors is a recognized limitation to such approach requiring the understanding of how phytophagous species can cope with such compounds. The velvetbean caterpillar (Anticarsia gemmatalis) is a key pest of soybean and well-adapted to its host proteinase inhibitors, which is rich in serine-proteinase inhibitors, particularly trypsin-like proteinase inhibitors. As the expression of cysteine proteinases in the midgut of the velvetbean caterpillar is a potential adaptation to circumvent its host defense, we assessed and characterized the digestive cysteine-proteinase activity from velvetbean caterpillars. Significant soluble and membrane-bound proteolytic activity was obtained and was consistent with those of cysteine proteinases based on the substrate and inhibitors used for their characterization. The K m and V max values obtained were 2.35 ± 0.50 mM and 40.89 ± 6.68 nmol min−1 mg−1 for the soluble proteinases and 0.33 ± 0.03 mM and 24.54 ± 0.67 nmol min−1 mg−1 for the membrane-bound proteinases, range of values also consistent with cysteine proteinases. Therefore, the proteolytic activity observed in the velvetbean caterpillar midgut is consistent with that of cysteine proteinases providing preliminary support for the contention of their potential involvement mitigating the negative effects of serine-protease inhibitors in this species.  相似文献   

16.
The aim of the study is to compare selected theoretical distributions (normal, lognormal, Weibull, gamma, logistic, and exponential) in describing the tree diameter (DBH) distributions of mixed near-natural forests consisting of fir Abies alba Mill. and beech Fagus sylvatica L. growing in various vertical structures. Tree DBH data were collected between 1997 and 2008 from 51 sample plots established in the Świętokrzyski National Park in Poland. The empirical data represent differentiated DBH distributions, ranging from almost symmetric to extremely asymmetric ones. The chi-square test and the modified Kolmogorov–Smirnov test were chosen for the goodness-of-fit testing. In addition to the test statistics, the bias (B), the root mean square error (RMSE) and the graphical method (quantile–quantile plots) were used. In one-storied stands, the most suitable distributions were the normal and logistic distributions; in two-storied and multilayered stands, the Weibull and gamma distribution were the most suitable; and in selection stands, the exponential distribution was the most appropriate to describe the DBH distribution. The order of precision of the tested distributions (from the highest to the lowest) was Weibull, gamma, logistic, normal, exponential, and lognormal. The normal and exponential distribution should be applied only to one-storied and selection forests, respectively. The least suitable distribution for DBH distribution modelling was the lognormal one.  相似文献   

17.
We derived an allometric model of the height–diameter curve for even-aged pure stands, which was a modification of the earlier model proposed by Inoue (2000a). An individual-dependent allometric equation was used as the height–diameter curve. Using the discriminant analysis method, all trees composed of a stand were stratified into upper and lower trees. It was assumed that both relationships between mean tree height H m and upper tree height H u and between mean DBH D m and mean DBH of upper trees D u could be described by the time-dependent allometric power equations. The height–diameter curve showed an average relationship between tree height and DBH of a given stand at a given time, and hence it could be assumed that the height–diameter curve contained two points (D m , H m ) and (D u , H u ). With these assumptions, we derived an allometirc model of height–diameter curve, which allowed the coefficients of the curve to be estimated from mean tree height and mean DBH. The proposed model was fitted to Japanese cedar (Cryptomeria japonica D. Don) data. The error ratio of the allometric model ranged from 2.254% to 13.412% (mean = 6.785%), which was significantly smaller than that of the earlier model. When the error of mean tree height was ±1.0 m or less, the effect of the error of mean tree height on the error ratio was comparatively small. This suggested that the error of ±1.0 m in mean tree height could be accepted in the estimation of height–diameter curve using the allometric model. These features enable us to combine the allometric model with Hirata’s vertical angle-count sampling or growth models. In conclusion, the allometric model would be one of the most practical and convenient approaches for estimating the height–diameter relationship of even-aged pure stands.  相似文献   

18.
This work verifies the development threshold of the pupal stage of L. serricorne whose larva fed exclusively on dried tobacco leaves. In previous work, using the thermal constant equation, this threshold was found to be 13.8 °C and the thermal constant to range from 89.05 to 94.05 day-degrees (°C). Lower temperatures, 10.5±0.5, 11.5±0.5 and 12.5±0.5 °C, close to this threshold, were tested in the absence of light and at a relative humidity of 65±3% . It was found that no development of either larva or pupa exists below this threshold  相似文献   

19.
叶蜂科(Tenthredinidae)两新种(膜翅目:广腰亚目)   总被引:1,自引:0,他引:1  
本文记述了危害林木的叶蜂(Tenthredinidae)两新种。一种为刺楸叶蜂(Conaspidiakalopanacis),隶属于叶蜂亚科(Tenthredininae),同盾叶蜂属(Conaspidia Konow),危害刺楸(Kalopanax septemlobus Koidz.)树叶,据报道1975年江西省萍乡市刺楸受害有虫株率达90%。另一种为杨潜叶叶蜂)Messa taianensis),隶属于黑特叶蜂亚科(Heterathrinae),潜叶叶蜂属(Messa Leach),为害小叶杨、小青杨、欧美杨等,据报道1978年辽宁省鞍山市台安县西平林场一片17年生小叶杨林,受害严重,虫口密度很大,平均每株树有一半左右  相似文献   

20.
Wood Science and Technology - In order to study the detailed water extract of wood components in birch under hydrothermal treatment, xylem sap obtained by mechanical...  相似文献   

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