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1.
测定了4种植物源杀虫剂对落叶松毛虫Dendrolimus superans (Butler)幼虫室内毒力,结果表明0.4％蛇麻子素、1％苦皮藤素、0.3％印楝素乳油稀释1000倍、1500倍、2000倍液对落叶松毛虫2龄幼虫72 h校正死亡率为20.53％ ～ 92.84％,其中1000倍液校正死亡率为80.12％ ～92.84％;对4龄幼虫的校正死亡率为30.01％～80.22％,其中1000倍液校正死亡率为68.16％～ 80.22％.2％烟碱·苦参碱乳油500,1000,1500倍液对2龄和4龄幼虫72 h校正死亡率分别为42.34％ ～93.82％和41.16％～85.49％.4种植物源杀虫剂1000倍液对2龄和4龄落叶松毛虫的毒力均存在差异性. 相似文献
2.
通过试验，证明超低容量喷洒灭幼脲Ⅲ号有效成份１５０ｇ／ｈｍ２杀虫速度快，效果好，施药后４～８ｄ即进入死亡高峰，２４ｄ校正杀虫率达９８％以上；施药后２５ｄ，施药区平均百叶重比对照区增加３１．４％，年胸径生长量比对照增加１１２．５％。泡桐叶甲第１代的１～２龄幼虫期（６月上中旬）是飞机喷洒灭幼脲Ⅲ号防治泡桐叶甲的关键时期。泡桐叶甲各龄级幼虫对该药的敏感程度依次为３～４龄＞１～２龄＞５龄。幼虫取食后可持续影响到蛹、成虫，使之产生畸形，对害虫控制作用持久。 相似文献
3.
本文探讨利用肿腿蜂和肿腿蜂带菌防治光肩星天牛（Ａｎｏｐｌｏｐｈｏｒａｇｌａｂｒｉｐｅｎｎｉｓ（Ｍｏｔｓｃｈ））幼虫。室内试验，肿腿蜂对光肩星天牛３龄幼虫寄生率１００％；对４龄幼虫２５％，对５龄幼虫无寄生效果；肿腿蜂带球孢白僵菌和肿腿蜂带拟青霉对４～５龄幼虫寄生死亡率分别为８７．５０％和９０．６３％用肿腿蜂进行林间放蜂防治试验，以２次／年，每次１００头／株，可防３龄以内皮下幼虫，防治效果为８６．０２ 相似文献
4.
丰宁新松叶蜂ＮｅｏｄｉｐｒｉｏｎｆｅｎｇｎｉｎｇｅｎｓｉｓＸｉａｏｅｔＺｈｏｕ系甘肃新记录，在甘肃哈思山林区１年１代，以老熟幼虫吐丝结茧变为预蛹在土壤腐殖质层或枯枝落叶层内超冬，翌年６月中旬为羽化盛期，６月下旬为孵化盛期，８月中旬结茧化蛹，幼虫６龄，３龄前食量小，抗性弱，是防治的最佳时机，用２．５％功夫乳油２．５％溴氰菊酯乳油８０００倍液喷雾，用２５％灭幼脲胶悬液２０～４０ｍｍｏｌ喷雾，防治效果均 相似文献
5.
甘伪小眼夜蛾生物学特性与防治 总被引：1，自引：0，他引：1
甘伪小眼夜蛾Pseudopanolis kansuensis Chen系新种，在甘肃哈思山林区1年1代，取食油松Pinus tabulae formis Carr,叶和嫩皮，在土壤腐殖层或枯枝落叶层内化蛹越冬，翌年4月下旬至5月上旬为羽化盛期，5月上旬为产卵盛期，成虫具有越光性，幼虫受惊后吐丝下垂，幼虫5龄，2龄前食量小，抗性弱，是防治的最佳时机，6月中旬被龄幼虫期用25％灭幼脲Ⅲ号胶悬剂，2．5％功夫乳油，尿素混合液，飞机低容量喷雾，杀虫率可达88．5％。 相似文献
6.
肿腿蜂、肿腿蜂带菌防治光肩星天牛幼虫试验研究 总被引：5，自引：1，他引：4
本文探讨利用肿腿蜂和肿腿蜂带菌防治光肩星天牛［Ａｎｏｐｌｏｐｈｏｒａｇｌａｂｒｉｐｅｎｎｉｓ（Ｍｏｔｓｃｈ）］幼虫。室内试验，肿腿蜂对光肩星天牛３龄幼虫寄生率１００％；对４龄幼虫２５％，对５龄幼虫无寄生效果；肿腿蜂带球孢白僵菌和肿腿蜂带粉拟青霉对４～５龄幼虫寄生死亡率分别为８７．５０％和９０．６３％。用肿腿蜂进行林间放蜂防治试验，以２次／年，每次１００头／株，可防３龄以内皮下幼虫，防治效果为８６．０２％。林间释放肿腿蜂带（球孢白僵菌Ｚ２８＋粉拟青霉Ｚ２６）混合菌，以２次／年，每次１００头／株，防治效果最佳为９１．３４％，可防皮下和木质部幼虫。肿腿蜂带粉拟青霉Ｚ２６，２次／年，每次１００头／株，防治效果为８５．６０％，肿腿蜂带球孢白僵菌Ｚ２８，１次／年，每次２００头／株，防治效果为７２．４４％。 相似文献
7.
１９９０～１９９３年，应用２０％三唑磷乳油进行防治马尾松毛虫和鞭角华扁叶蜂幼虫试验，结果如下：①采用３００～１６００倍液防治第１代≤３龄马尾松毛虫幼虫，７２ｈ后，其杀虫率为９０．４％～１００％，防治≥４龄幼虫的，其杀虫率为８９．１％～９５．８％；防治第２代≤３龄幼虫，７２ｈ后，其死亡率为７１．９％～９０．７％．②采用５００～２０００倍液防治鞭角形扁叶蜂幼虫，并与同倍数的４０％水胺硫磷、５０％甲胺磷进行对比，使用三唑磷的，７２ｈ后，其死亡率力４０．３％～９９．２％，９６ｈ后残毒药效为１４．２％～１００％，优于甲胺磷，次于水胺硫磷．在本试验设计浓度范围内，它们的杀虫效果（包括残毒药效）都是随浓度加大而随之提高． 相似文献
8.
埃及柽麦蛾的生物学特性研究 总被引：1，自引：0，他引：1
埃及柽麦蛾在新疆 1年发生 3代 ,以老熟幼虫或蛹在枯枝落叶中越冬。成虫寿命平均 6～ 7天。卵散产 ,卵期 7天 ,幼虫共有 5龄 ,各龄幼虫变化较大。埃及柽麦蛾的幼虫有粘叶形成丝巢的习性 ,给防治带来一定的困难 相似文献
9.
云南松尺蛾在楚雄地区一年发生一代，以幼虫越冬，翌年开春危害云南松和华山松针叶，老熟幼虫吐丝下垂于枯枝落叶层内化蛹。害虫的发生、危害与林分组成、林木长势、海拔和坡向等环境因子有密切关系。根据尺蛾的生活习性，可以采取相应的防治措施。 相似文献
10.
利用Bt制剂防治落叶松毛虫的研究 总被引：1，自引：0，他引：1
绰源林业局于１９９２～１９９４年间落叶松毛虫（Ｄｅｎｄｒｏｌｉｍｕｓｓｕｐｅｒａｎｓ）猖獗成灾。由于长期化学防治，不仅松毛虫的抗药性增大，而且污染了环境，破坏了生物多样性。为此，我们于１９９３～１９９４年间用Ｂｔ制剂进行了防治试验。湖北农科院生物农药厂生产的Ｂｔｋｕｒｓｔｒａｋｉ亚种血清型Ｈ３ａ３ｂ防效较好，地面防治６～７龄松毛虫（１００倍液）在日平均温度１６．５℃时，死亡率在８０％以上，南开大学生产的Ｂｔｋａｎｙａｅ亚种血清型Ｈ４ａ４ｃ防治落叶松毛虫３～４龄幼虫、稀释５０倍液进行低溶量飞防效果可达７５．２％。 相似文献
11.
Our study focuses on predicting the ultimate short-term load carrying capacity of timber-to-timber connections with dowel-type fasteners. The wide range of possible configurations in practice makes the resolution of these values by tests unrealistic. Moreover, different current regulations do not consider some specific failure mechanisms. In many countries, the reduction of resistance involved by this phenomenon is taken into account by considering an effective number of dowels (nef) smaller than the actual number of dowels (n) in the connection. However, these different regulations disagree on the values of nef and on other points (spacing, partial coefficient of security, formulas). These discrepancies in design rules invite the fundamental research on this topic and, therefore, new methods are sought in order to estimate the load carrying capacities of the connections. In the light of these, our approach consists of predicting the load carrying capacity with the neural network numerical tool. The results obtained by this analysis tool are satisfactory, although the model remains complex. Subsequently, we focus on the simplification of this numerical model with classical regression techniques in order to implement it in a design code. 相似文献
12.
Ophiostoma species were isolated from bark beetles and Abies mariesii, A. veitchii and A. homolepis attacked by the beetles in Nikko, Tochigi, central Honshu, Japan. One to two Ophiostoma species were frequently isolated from each species of bark beetle. Ophiostoma subalpinum was the most common associate of Cryphalus montanus. Ophiostoma sp. B as well as O. subalpinum was a common fungus associated with Polygraphus proximus. Ophiostoma europhioides was isolated from Dryocoetes hectographus and D. autographus as one of the common associates. Ophiostoma sp. J and Ophiostoma sp. S were frequently isolated from D. autographus and D. striatus, respectively. These fungi seem to have specific relationships with particular bark beetles. Ophiostoma sp. B, Ophiostoma sp. J and Ophiostoma sp. S have unique morphological characteristics and appear to be new species. Five trees of A. veitchii, approximately 43 years old, were inoculated with five Ophiostoma species to assess the relative virulence of the fungi. Ophiostoma subalpinum, Ophiostoma sp. B, and O. europhioides had relatively higher virulence than the other species studied. 相似文献
13.
Parasitic Hymenoptera from the suprafamily Ichneumonoidea attacking the horse chestnut leafminer Cameraria ohridella Deschka & Dimic (Lepidoptera: Gracillariidae) were studied in southwest Slovakia during 2000 and 2001. The search for such species resulted in the determination of eight ichneumonid species, Gelis agilis (Fabricius), Itoplectis alternans (Gravenhorst), I. clavicornis (Thompson), I. maculator (Fabricius), Scambus annulatus (Kiss), S. brevicornis (Gravenhorst), Zatypota percontatoria (Müller), Adelognathus sp. and a braconid Colastes braconius Haliday. The most abundant species was S. annulatus. All these species recorded are polyphagous and often facultative hyperparasitoids, except C. braconius, which departs from this norm in not being hyperparasitic. The presence of more diversified native parasitoids and hyperparasitoids from the Ichneumonoidea predicate a slow successive adaptation of the parasitoid fauna to the invasive host, Cameraria ohridella. 相似文献
14.
Contour hedgerows of multipurpose tree species in the sloping tea lands of Sri Lanka are expected to reduce soil erosion and
also add significant amounts of plant nutrients to the soil via periodic prunings. The objective of this experiment was to characterize the biomass decomposition pattern and quantify the
amount of nutrients added through prunings of six tree species (Calliandra calothyrsus, Senna spectabilis, Euphatorium innulifolium, Flemingia congesta, Gliricidia sepium and Tithonia diversifolia) currently being used in hedgerows associated with tea. Withered leaf and stem prunings (50 g) were enclosed in 2-mm litter
bags, placed at 5-cm depth and retrieved after one, three, six, nine and 12 weeks. Loss of initial dry weight, N, P and K
was measured. Single exponential decay function adequately described both dry weight and nutrient loss. Tree species differed
significantly in their rate of breakdown with decomposition constants (k) varying from 0.0299 to 0.2006 week−1 for leaves and from 0.0225 to 0.0633 week−1 for stems. Gliricidia showed the highest k for leaves with the rest in the following descending order: Senna > Tithonia ≥ Euphatorium > Calliandra > Flemingia. A similar pattern was observed for loss of all nutrients with Calliandra and Flemingia always having lower k values than the rest. Although N immobilization was not observed, immobilization of P and K was observed
during the first week of incubation in some species, particularly in stem prunings. Annual biomass of prunings differed significantly
between tree species in the following descending order: Calliandra > Senna > Flemingia > Tithonia > Gliricidia > Euphatorium. Calliandra added the greatest amount of nutrients annually to the soil with Euphatorium adding the least. Calliandra prunings provided the annual total K requirement and 49% of the N requirement of mature tea. However, none of the species
provided more than 5% of the P requirement. It is concluded that among the tree species tested, Calliandra and Flemingia are the most suitable for contour hedgerows in tea plantations of this agroclimatic region because of their higher soil nutrient
enrichment capacity and slower decomposition rates which would minimize leaching losses.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
15.
Steven Maranz Amadou Niang Antoine Kalinganire Djeneba Konaté Bocary Kaya 《Agroforestry Systems》2008,72(3):231-239
Baobab leaves form an important part of the local diet in Sahel countries and elsewhere in Africa. Existing leaf nutritional
data and agroforestry performance information are based solely on Adansonia digitata L., the baobab of continental Africa. The introduction potential of Adansonia species from the center of diversity in Madagascar and from Australia remains untapped. To assess this potential, the mineral
contents and B1 and B2 vitamin levels of dried baobab leaves were determined for five-year old trees of A. digitata, A. gibbosa (A. Cunn.) Guymer ex D. Baum, A. rubrostipa Jum. & H. Perrier (syn. A. fony Baill.), A. perrieri Capuron and A. za Baill. grown in an introduction trial in Mali. Nutritional data were evaluated against survival and vigor to identify promising
germplasm. Leaf vitamin and crude protein contents were highest in the Madagascar species, especially A. rubrostipa (B1 88 mg 100 g−1, B2 187 mg 100 g−1, protein 20.7% dry weight). However, the local species far outperformed the introductions in survival, tree height, basal
diameter and resistance to termites. We suggest grafting as a way of harnessing the vigor of well-adapted local baobab varieties
to the superior nutritional profiles of A. rubrostipa and others. Cross-species grafting tests in Adansonia were successful, thus creating new agroforestry possibilities with different scion/rootstock combinations. 相似文献
16.
Pavela R 《Fitoterapia》2004,75(7-8):745-749
The methanol extracts of eight species of medicinal plants were tested for insecticidal activity in third instar larvae of Egyptian cottonworm (Spodoptera littoralis). All extracts showed a certain degree of larval toxicity. The extracts of Ocimum basilicum, Origanum majorana and Salvia officinalis appeared to be highly toxic. The extracts significantly affected the growth indexes [relative growth rate (RGR), efficiency of conversion of ingested food (ECI), efficiency of conversion of digested food (ECD)]. 相似文献
17.
Yu Mei Zhang Ning Hua Tan Guang Zhi Zeng Abiodun Humphrey Adebayo Chang Jiu Ji 《Fitoterapia》2009,80(6):361-363
A new norlignan, (2R,3R,4S,5S)-2,4-bis(4-hydroxyphenyl)-3,5-dihydroxy-tetrahydropyran (1), together with 9 known compounds were isolated from the branches and leaves of Taxodium ascendens. Their structures were mainly determined on the basis of MS, IR, 1D and 2D NMR spectral evidences. Methanol extract showed inhibitory activity on carbonic anhydrase II with an IC50 value of 4.27 µg/ml, acetone extract and methanol extract inhibited activity of cathepsin B with IC50 values of 2.12 and 3.71 µg/ml, respectively. 相似文献
18.
The objective of this case study was to test the effectiveness of biocontrol for the rehabilitation of abandoned, diseased
(moniliasis, witches' broom and black pod) cocoa and to develop testable hypotheses regarding the effect of shade and biocontrol
timing. Three trial fields differed in their shade regimes. Biocontrol was administered starting either at flowering or pod
filling. Disease incidence and yield were compared with cultural control alone. Biocontrol reduced moniliasis from 49% to
25%, independent of the shading regime and application time. Witches' broom was most severe without shade and unaffected by
biocontrol. No significant effects on black pod were observed. Although biocontrol increased percentage healthy fruit independent
of shading and timing, only the shaded plot with biocontrol from flowering onwards responded with increased yield. Our hypothesis
is: 'In the rehabilitation of abandoned cacao, only fields under sustainable shade management and early onset of biocontrol
can realise their production potential.'
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
19.
Adult fungus gnat and shore fly populations were monitored in four container nurseries near Victoria, British Columbia. In general, populations of both insects were larger in summer than in winter. Also, both insects were more abundant in the nursery with a plastic-covered, soil floor, which favored moisture accumulation and build up of algae, liverworts and mosses, than in nurseries with other types of floors such as cement. Results of fungus isolations revealed that gnats and flies both harbor the seedling pathogens Botrytis cinerea and species of Fusarium and Phoma, plus several non-pathogenic fungi. The results are discussed in relation to nursery sanitation practices, their effects on gnat and fly populations, and some possible roles of these insects in seedling disease epidemiology. 相似文献
20.
Katsumi Togashi Yosuke Taga Kazunobu Iguchi Takuya Aikawa 《Journal of Forest Research》2008,13(2):127-131
Bursaphelenchus mucronatus Mamiya et Enda has been recovered for the first time from adults of the cerambycid beetle, Monochamus urussovi (Fischer), in Hokkaido, Japan. The nematode was also recovered from the inner bark of Picea jezoensis (Siebold et Zuccarini) Carrière and Abies sachalinensis (Fr Schmidt) Masters infested with M. urussovi larvae. PCR–RFLP analysis indicated that B. mucronatus in Hokkaido is the European type. 相似文献