首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 93 毫秒
1.
A panel of 18 rat x mouse somatic cell hybrid clones segregating individual rat chromosomes in different combinations was used to assign 23 biochemical loci to rat chromosomes. The chromosomal locations for these 23 loci were determined as follows: GOT1 on rat chromosome 1; HAGH on 2; ACP2, ADA, GANC, ITPA, and SORD on 3; LDHB on 4; PEPB on 7; GLB1 and HEXA on 8; IDH1 on 9; UMPH2 on 10; GUSB on 12; FH and PEPC on 13; PEPS on 14; ESD and NP on 15; DIA4 on 19; and PP on 20. In addition, ACP1 and GLO1 were reassigned to rat chromosomes 6 and 20, respectively. The chromosomal assignments of these loci extends the known syntenic homologies among rats, mice, and humans.  相似文献   

2.
不同寄主植物对云南紫胶虫自然种群的影响   总被引:7,自引:1,他引:6  
研究了云南紫胶虫(Kerria yunnanensis)在聚果榕、南岭黄檀、钝叶黄檀和偏叶榕上的发育、存活和繁殖情况.结果表明:在自然条件下,云南紫胶虫在钝叶黄檀上的种群初始密度最高,为181.17头·cm-2,聚果榕上最低,为145.27头·cm-2;雄虫占的比例以在南岭黄檀上最少,为0.19,偏叶榕和聚果榕上最多,为0.24;从幼虫到成虫的累积死亡率,南岭黄檀上最高,为90.03%,偏叶榕上最低,为87.05%;完成世代时间以在南岭黄檀上最长,为156 d,聚果榕上最短,为140 d;平均怀卵量以在南岭黄檀上最高,为536粒,聚果榕上最低,为345.86粒;虫体质量以在南岭黄檀上最大,为12.62 mg,偏叶榕上最小,为9.03 mg;世代净增值率以在南岭黄檀上最高,为48.51,聚果榕上最小,为32.79.综合比较4种不同寄主植物,南岭黄檀是云南紫胶虫夏季世代种群生长发育和繁殖最适宜的寄主.  相似文献   

3.
本文对我国春孢锈菌属(形式属)增补了以下9个种:1.腺梗菜春孢锈菌Aecidium adenocauli Syd. 寄主:腺梗菜Adenocaulon himalaicum Edgew (菊科Compositae) 2.臭椿春孢锈菌(新种) Aecidium ailanthi J.Y.Zhuang sp.nov.寄主:臭椿 Ailanthus altissima Swingle (苦木科Simaroubaceae)3.筋骨草春孢锈菌 Aecidium alugae Syd.寄主:紫背金盘 Ajuga nioponensis Makino (唇形科 Labiatae) 4.八角枫春孢锈菌 Aecidium alangii Hirats.& Yosh 寄主:长毛八角枫 Alangium kurzii Craib,瓜木A platanifoHum Harms (八角枫科 Alangiaeeae) 5.紫珠生春孢锈菌(新种) Aecidium callicarpivola J Y.Zhuang sp.nov.寄主:杜虹花 Callicarpa oedunculata R,Br.(马鞭草科Verbenaeeae) 6.吴茱萸春孢锈菌(新种) Aecidium evodiae J.Y.Zhuang sp.nov. 寄主:吴茱萸 Evodia rutaecarva (Juss.)Benth.(芸香科Rutaceae) 7.杨叶木姜子春孢锈菌(新种) Aecidium litseae-populifoliae J.Y.Zhuang sp.Nov.寄主:杨叶木姜子 Litsea povulifolia Gamble (樟科Lauraceae) 8.青海春孢锈菌(新种) Aecidium qinghaiense J Y.Zhuang sp.nov. 寄主:莴苣属一种Lactuca sp.(菊科Compo sitae) 9.合掌消春孢锈菌 Aecidium vincetoxici P.Henn.& Shirai 寄主:牛皮消 Cynanchum auriculatum Royle (萝藦科 Asclepiadaceae)  相似文献   

4.
目的了解实验所用常见致病真菌能否在常用医用原材料上生存及生存时间。方法选择8种常见致病真菌,活化后将它们分别接种在5种常用的医用原材料上,接种后及以后的每24h将接种有真菌的医用材料放入巯基乙酸盐液体培养基中并观察能否生存,记录存活时间。结果红色毛癣菌和须癣毛癣菌在棉布、纸板、铁皮、玻璃表面存活25~28d,在地板胶表面存活14~15d;新生隐球菌在棉布、纸板、铁皮表面存活24~27d,在玻璃和地板胶表面存活14~18d;茄病镰刀菌在上述5种材料上存活22~27d;石膏样小孢子菌在棉布、纸板、铁皮和玻璃表面存活20~27d,在地板胶表面存活8d;申克孢子丝菌在棉布、纸板、玻璃和地板胶表面存活17~24d,在铁皮表面存活10d;白念珠菌在棉布、纸板、铁皮和地板胶表面存活15~20d,在玻璃表面存活4d;犬小孢子菌在棉布、纸板、铁皮、玻璃和地板胶上存活时间分别为10d、9d、3d、2d和1d。结论实验所用各种真菌在医用原材料上都能存活,其时间长短不仅与菌种有关,还与所存在的材料有关。真菌在吸水性强、表面粗糙的材料(棉布、纸板)上的平均存活时间长于在吸水性差、表面光滑的材料(玻璃、铁皮和地板胶)。  相似文献   

5.
【目的】异迟眼蕈蚊Bradysia difformis Frey的幼虫取食为害作物的地下部分,影响作物的品质,为了明确韭菜、蚕豆、生菜、白菜和甘蓝5种植物对异迟眼蕈蚊生长发育以及繁殖的影响。【方法】本试验采用室内人工饲养测定的方法,研究了5种不同植物对异迟眼蕈蚊生长发育,繁殖力和存活率的影响,并统计了其对异迟眼蕈蚊种群参数的影响。【结果】结果表明:卵到蛹的发育历期依次为甘蓝、白菜、韭菜、生菜、蚕豆;5种植物对雌雄虫寿命影响不显著,对雌虫产卵量以及蛹重均有影响,其中在韭菜上的产卵量最大,甘蓝最少,在韭菜上蛹最重,生菜上蛹最轻;异迟眼蕈蚊的存活率随着生长发育降低,总体在韭菜上的存活率高于其他寄主植物,在生菜上的存活率均最低。统计分析不同植物对异迟眼蕈蚊种群参数的影响,净增殖率和内禀增长率在韭菜上最大而在甘蓝上最小;平均世代周期在蚕豆上最短,甘蓝上最长;种群加倍时间在韭菜上最短,而在甘蓝上最长。【结论】由此可知,异迟眼蕈蚊均可以在韭菜,蚕豆,生菜,白菜和甘蓝上完成生长发育及繁殖,其对5种植物的适应性依次为:韭菜、蚕豆、白菜、甘蓝和生菜。  相似文献   

6.
The biology of the pentatomid Dichelops melacanthus (Dallas) feeding on cultivated and non-cultivated plants was studied in the laboratory. Nymph mortality varied from approximately 60 on corn (seed mature) to 77% on wheat (ear immature); no nymphs survived on seedlings of corn or wheat. Nymph developmental time on soybean, corn or wheat (seed, pod or ear) varied from 25.5 to 32.8 days. Body weight at adult emergence was similar and greater on most foods than on wheat ear. Nymphs fed preferentially on soybean (pod immature). On non-cultivated hosts, nymphs showed high mortality (73%) on crotalaria (pod immature); on tropical spiderwort (stem) all nymphs died. Nymphs took longer time to develop on crotalaria and/or on spiderwort than on soybean. Body weight at adult emergence did not differ on crotalaria or soybean. Survivorship decreased with time on most foods, with approximately 50% of adults alive at day 30. On corn and wheat seedlings approximately 80% of adults were dead on day 20. Adult longevity ranged 31-43 days, except on corn and wheat seedlings < 15 days. Females % ovipositing peaked ( approximately 76%) on soybean (pod or seed immature), and was minimum ( approximately 9%) on wheat ear (immature); no females reproduced on seedlings of corn or wheat. Preoviposition period was shorter ( approximately 12 days) on soybean (immature pod or seed) and longer ( approximately 37 days) on wheat (ear immature). Fecundity was similar and higher on all foods than on wheat (ear immature). Body weigh gain occurred on all foods, but on corn and wheat seedlings. Adults fed preferably on soybean (pod immature and seed mature); wheat (seedling) was the least preferred food.  相似文献   

7.
D. BAINES 《Ibis》1989,131(4):497-506
Data on the breeding success of Lapwings Vanellus vanellus on unimproved and improved grassland, with comparative data for arable land, were obtained from a study on 760 Lapwing clutches. The study was undertaken in the Eden Valley, Cumbria, and Teesdale, Co. Durham, between 1985 and 1987. First clutches were larger on unimproved grassland with a mean of 3.73 eggs compared to 3.61 eggs on improved grassland. In contrast, replacement clutches were larger on improved areas (3.90 eggs) than on unimproved (3.47 eggs). On average, 40% of eggs laid on unimproved pastures hatched compared to only 17% on improved pastures. No significant difference in hatching success was found between unimproved and improved meadows with 32% and 22% of eggs hatching, respectively. Overall, 73% of unsuccessful first clutches were replaced on unimproved pastures, whereas on meadows and improved pastures combined, only 32% were replaced. Survival of small chicks was highest on unimproved areas. Production on unimproved areas was sufficient to replace adult losses and so maintain numbers, whereas on improved land production was too low to maintain existing breeding densities. Hatching success on unimproved areas was similar for the four species of wader considered. On improved areas, Redshank hatching success was relatively high, with 54% of pairs producing chicks, compared to 35% for Lapwing and 23% for Curlew.  相似文献   

8.
Abstract The invasive Q biotype whitefly was first detected in the US on poinsettia in 2004 and is still not a pest outside of greenhouse environments in the US. To assess the potential for the establishment of the Q biotype on field crops, population cage experiments were conducted to compare the performance of a poinsettia‐derived Q population named P’06 on poinsettia and six field crops (alfalfa, tomato, melon, cotton, cowpea and cabbage). P’06 adults reared on poinsettia as nymphs laid eggs on all six field crops. Significantly more eggs were laid on alfalfa, tomato, melon and cotton than on cabbage, cowpea and poinsettia. These eggs hatched and the nymphs developed to adults on the six field crops. Relative to poinsettia, whitefly survival was similar on cowpea, alfalfa, tomato and cabbage, but significantly higher on cotton and melon. Moreover, P’06 had significantly shorter development times from egg to adult on cotton, melon, cowpea, tomato and alfalfa than they did on poinsettia. However, the F1 adults raised on the six field crops had significantly shorter lifespans and laid 11‐ to 18‐fold fewer eggs than did the F1 adults raised on poinsettia. Taken together, while P’06 may have some potential to establish on field crops, the shorter lifespans and extremely low fecundities of the F1 adults raised on the six field crops suggests that P’06 is incapable of rapidly adapting to them. Poor adaptation to field crops may explain, at least partially, why the Q biotype has not established in the US field system.  相似文献   

9.
Two new species of Leporinus are described from tributaries of the Rio Amazonas in Brazil. One species is known from the Jari and Tapajós River basins, and is identified on the basis of a gas bladder reduced in size, a dark midlateral stripe on the body, dark transverse bars on the dorsum, a subinferior mouth, three teeth on the premaxilla, four teeth on the dentary and 16 scale rows around the caudal peduncle. The second new species is known from the Tocantins, Xingu and Tapajós River basins, and is identified on the basis of three dark longitudinal stripes on the body, a subinferior mouth, three teeth on the premaxilla, four teeth on the dentary and 12 scale rows around the caudal peduncle. In addition, Leporinus striatus is redescribed based on type and additional specimens from the Río de La Plata, Amazonas, Orinoco, Atrato, Magdalena and Sinu River basins. Leporinus striatus is identified on the basis of four dark longitudinal stripes on the body, a subterminal mouth, three teeth on the premaxilla, four teeth on the dentary and 16 scale rows around the caudal peduncle.  相似文献   

10.
Abstract. The vegetation on a wet mountain slope on Haleakala (an oceanic island) is compared with that on Kinabalu (a continental island) to examine relationships between regional floristic richness and α- and β-diversities. The two mountains are similar in their constant tropical climate, generic and family-level floristic elements and geological age of the summit regions, but different in regional floristic richness (rich on Kinabalu vs. poor on Haleakala). α-diversity of canopy and subcanopy tree species was much higher on Kinabalu than in comparable zones on Haleakala. Average turnover rate of species (as logarithmic community similarity) on the slope was one order of magnitude greater on Kinabalu than on Haleakala (0.127 vs. 0.017 per 100 m alt.). While there were genera with wide altitudinal ranges on both mountains, a large proportion of the genera was differentiated into parapatric altitudinal congeners on Kinabalu. By contrast, most genera are altitudinally monotypic on Haleakala. The number of sympatric congeners per genus, and the frequency of multi-specific genera per plot were high on lower slopes but decreased with increasing altitude on Kinabalu, whereas the values were low across all altitudes on Haleakala. These patterns suggest that sympatric and parapatric species radiation was less on Haleakala than on Kinabalu. This may be related to Haleakala's initially poor and disharmonic flora.  相似文献   

11.
庄剑云  魏淑霞 《菌物学报》2011,30(6):853-860
补充记载了采自海南省的9种锈菌。甲竹Bambusa remotiflora上的华南柄锈菌Puccinia austrosinensis、大花紫薇Lagerstroemia speciosa上的紫薇夏孢锈菌Uredo lagerstroemiae和海南薯Ipomoea sumatrana上的宽乳单胞锈菌Uromyces latimammatus为新种;厚叶素馨Jasminum pentaneurum上的巴氏查科锈菌Chaconia butleri、猪肚木Canthium horridum上的鱼骨木驼孢锈菌Hemileia canthii、牛筋果Harrisonia perforata上的牛筋果无眠多胞锈菌Kuehneola harrisoniae、毛咀签Gouania javanica上的椴叶咀签柄锈菌Puccinia gouaniae-tiliaefoliae、蒲桃Syzygium jambos上的番石榴柄锈菌Puccinia psidii以及象草Pennisetum purpureum上的钝叶草柄锈菌Puccinia stenotaphri为中国新记录。引证的标本均保存于中国科学院菌物标本馆(HMAS)。  相似文献   

12.
以9个大白菜品种和10个结球甘蓝品种为试材,对位于芸薹属A基因组10个连锁群的207对SSR引物进行PCR筛选,共筛选出33个大白菜相对于结球甘蓝的特异SSR标记,涉及了大白菜的10个连锁群,其中位于A1连锁群3对,A2连锁群4对,A3连锁群5对,A4连锁群2对,A5连锁群3对,A6连锁群4对,A7连锁群2对,A8连锁群1对,A9连锁群2对,A10连锁群7对。为进一步利用SSR标记鉴定结球甘蓝—大白菜异附加系奠定了基础。  相似文献   

13.
鸟类群落研究进展   总被引:28,自引:3,他引:28  
崔鹏  邓文洪 《动物学杂志》2007,42(4):149-158
鸟类群落的研究一直是鸟类生态学研究的重要领域,研究内容主要集中在以下几个方面:群落的组成结构、集团结构、生态位与种间关系、动态与演替、群落与栖息地关系以及城市化对鸟类群落影响。群落的组成与结构、动态与演替以及群落与栖息地关系的研究是过去20年间的研究热点,但有关城市化对鸟类群落影响的研究还比较少。本文在总结国内外鸟类群落生态学研究的基础上,重点讨论了目前的研究热点和今后的发展趋势,以期促进我国鸟类群落生态学的研究。  相似文献   

14.
We investigated plant-mediated effects of the stem gall wasp, Dryocosmus kuriphilus Yasumatsu (Hymenoptera: Cynipidae), on other herbivores on the chestnut tree Castanea crenata. In the early season, leaves emerged earlier and in greater numbers on galled shoots than on ungalled shoots. On galled shoots the leaf to shoot biomass ratio was lower and the leaves were physically different. In May and June the concentration of nitrogen in leaves was higher on galled shoots than on ungalled shoots. In July, the water content of leaves was lower on galled shoots. In May and June, the number of aphids, Myzocallis kuricola Matsumura (Homoptera: Aphidoidea), on leaves was higher on galled shoots than on ungalled shoots, but the opposite was true at the end of July. Laboratory experiments showed that aphid fecundity and body weight decrease were higher in May and June when aphids fed on leaves on a galled shoot than when they fed on those on ungalled shoots. In contrast, aphid performance in July was greater on ungalled leaves than on galled leaves. Our findings suggest that gall initiation in a chestnut tree affected aphid performance by affecting host plant quality.  相似文献   

15.
Treatment of cancers with cytotoxic agents such as alkylating drugs often, but not always results in transient to permanent testicular dysfunction. The present study was planned to investigate the effects of dacarbazine [5-(3,3-dimethyltriazeno) imidazole-4-carboxamide] on testicular function in mice. Swiss albino mice (9-12 weeks old) were treated with 0, 5, 25, 50, or 100mg/kg body weight/day dacarbazine (i.p.) for 5 days at intervals of 24h between treatments. Mice were sacrificed on days 7, 14, 21, 28, 35, 49, and 70 after the last treatment (6 mice/dose/sample time), and the epididymal sperm count, sperm motility, sperm morphology, testicular histopathology (qualitative histopathology, seminiferous tubular diameter and epithelial height), and intra-testicular levels of testosterone and lactate dehydrogenase were assessed. Dacarbazine decreased the body weight only on day 28 at 25mg/kg dose-level, but increased the paired testes weights at 50mg/kg on day 7, at 25-100mg/kg on day 14, and at 25 and 50mg/kg on day 21 (P<0.05-0.01; one-way ANOVA and Bonferroni's post hoc test). The sperm count was decreased on all sampling days except at 5 and 25mg/kg dose-levels on day 70, but with severe oligospermia on days 28 and 35 (P<0.05-0.001). The sperm motility was decreased at 100mg/kg on days 14 and 21, at 5, 25, and 100mg/kg on day 28, and at all dose-levels on day 35 (P<0.05-0.001). Dacarbazine induced both head and tail abnormalities and some sperms with cytoplasmic droplets, but significant increase was seen in all dose groups on days 14 and 21, and at 100mg/kg dose-level on day 35. Drug-induced epithelial sloughing was seen on days 14-35 and other histopathological changes observed were vacuoles and abnormal cells. The STD was increased at 25-100mg/kg on day 7, at all dose-levels on day 14, at 50-100mg/kg on days 21 and 28, but without any effects on days 35-70 (P<0.05-0.001), and the tubular lumen was found dilated. The SE was increased on days 7, 21 and 28 at 100mg/kg and on day 14 at 50-100mg/kg. Dacarbazine reduced the intra-testicular testosterone level at 100mg/kg on day 7, at 5, 50 and 100mg/kg on day 14, at all dose-levels on days 21, 28, and 35, and at 50mg/kg on day 49 (P<0.05-0.001). The intra-testicular lactate dehydrogenase concentration increased at all dose-levels up to day 35, but without any effect on days 49 and 70 (P<0.05-0.001). There was no particular dose-response of dacarbazine on any parameters tested. The sperm count (except on day 7-positive correlation; Pearson product moment correlation) or sperm motility did not have any relation but increase in abnormal sperms showed negative correlation with decrease in testosterone level on days 7, 21 and 28. Decrease in sperm count was in negative correlation on days 14 and 35, and increase in abnormal sperms showed positive correlation on day 35 with increase in LDH level. Finally, the decrease in sperm motility had no correlation with increase in abnormal sperm shapes. We conclude that dacarbazine is genotoxic and cytotoxic to the mouse testis in a transient fashion, and these effects are exerted along with decrease in testosterone and increase in lactate dehydrogenase levels in the testis.  相似文献   

16.
Cellular growth and collagen biosynthesis were compared in dermal calf fibroblasts cultured on plastic or on a reconstituted basement membrane gel, termed matrigel. This matrix, extracted from Engelbreth-Holm-Swarm tumors, consists mainly of laminin, entactin, type IV collagen, and heparan sulfate proteoglycan. The multiplication rate of fibroblasts grown on matrigel was stimulated compared to that of monolayered cells cultured on plastic, and these cells formed multilayers after 4 days. Protein and collagen biosynthesis was reduced in fibroblasts cultured on matrigel. A higher proportion of the newly synthesized collagen (40%) was incorporated to the extracellular matrix in cultures grown on matrigel than in those grown on plastic (14%). Type III collagen was the preferential collagen type deposited on matrigel, and the ratio of type III:type I collagens secreted in the medium was also slightly higher in cultures grown on matrigel. Partially processed collagen was more abundant in fibroblasts grown on matrigel than in cells cultured on plastic. Finally, cells grown on matrigel exhibited a higher catabolic activity than cells grown on plastic. In this experimental model, the reconstituted basement-membrane matrix seems to influence the activities of fibroblasts significantly.  相似文献   

17.
B型烟粉虱在四种葫芦科寄主植物上的发育和繁殖   总被引:4,自引:0,他引:4  
研究了B型烟粉虱在4种葫芦科寄主植物黄瓜、节瓜、苦瓜和丝瓜上的发育和繁殖特性.结果表明,B型烟粉虱在节瓜上的世代发育历期最短,为19.3 d,在苦瓜上的世代发育历期最长,为29.0 d;世代存活率在黄瓜上最高,为92.85%,在苦瓜上最低,为53.08%;平均单雌产卵量在黄瓜上最多,为187.4粒,苦瓜上最少,为30.0粒;雌成虫寿命以在黄瓜上最长,为25.2 d,在苦瓜上最短,为10.9 d.B型烟粉虱在黄瓜、节瓜、苦瓜和丝瓜上的内禀增长率(rm)分别为0.1453、0.1429、0.0616和0.1055.综合比较4种葫芦科植物,黄瓜是B型烟粉虱的最适宜寄主.  相似文献   

18.
Host plant species can affect the behavior and attributes of parasitoids, such as host searching, oviposition, and offspring fitness. In this study, parasitism, host feeding, and sex ratios of Diglyphus isaea (Walker) (Hymenoptera: Eulophidae) on Liriomyza huidobrensis (Blanchard), Liriomyza sativae Blanchard, and Liriomyza trifolii (Burgess) (Diptera: Agromyzidae) larvae reared on Phaseolus vulgaris L., Pisum sativum L., Solanum lycopersicum L., and Vicia faba L. were determined. In no-choice tests, L. huidobrensis had the highest rate of parasitism when reared on P. vulgaris (46%), L. sativae when reared on V. faba (59%) and P. vulgaris (59%), and L. trifolii when reared on S. lycopersicum (68%). Host feeding in no-choice tests ranged between 2% and 36% and was highest on L. trifolii reared on V. faba. Results of choice tests showed a significant interaction effect for host plant and Liriomyza species on parasitism and host feeding. Within plant mixtures, L. sativae reared on P. vulgaris had the highest rate of parasitism (31%), followed by L. trifolii on S. lycopersicum (29%) and L. huidobrensis on V. faba (28%). Host feeding was highest on L. trifolii reared on S. lycopersicum (14%) and lowest on L. huidobrensis reared on P. sativum and S. lycopersicum (1%). In some instances, plant mixtures resulted in a higher proportion of females of D. isaea than single plant species. The highest proportion of females was obtained in plant mixtures on L. huidobrensis and L. trifolii on V. faba (71 and 72%, respectively). This study suggests that planting crop mixtures can potentially lead to higher proportions of females, thus improving parasitism and host feeding, depending on Liriomyza and host plant species.  相似文献   

19.
Development, survivorship, pupal weight, oviposition, and life table parameters of the oriental tobacco budworm, Helicoverpa assulta Guenée, were evaluated in the laboratory on an artificial diet, pepper (Capsicum frutescens L.), and tobacco (Nicotiana tobacum L.). We found that the average developmental time of immature stages was longest on tobacco (36.2 d), intermediate on pepper (34.4 d), and shortest on artificial diet (33.5 d). Immature survival from egg to pupa varied from 31% on tobacco, 43% on pepper, and 74% on artificial diet. Pupal weight ranged from 197.4 mg/pupa on tobacco, 233.1 mg/pupa on pepper and 253.4 mg/pupa on artificial diet. The average numbers of eggs laid by adults reared as larvae on the artificial diet, pepper, or tobacco were 614, 421 and 334 eggs/female, respectively. Numbers of remaining eggs in ovaries of the adult females reared as larvae on the artificial diet, pepper, or tobacco were 16, 26, and 42 eggs/female, respectively. The longevity of adult females developed from larvae reared on the three diets was not significantly different, whereas the longevity of male adults from the larvae reared on artificial diet was longer (16.8 d) than that for males reared on tobacco (13.8 d) and pepper (13.3 d). The intrinsic, finite, gross, and net rates of increase were highest for females reared as larvae on artificial diet, lowest for females emerging from larvae reared on tobacco, and intermediate for females emerging from larvae reared on pepper. Generation times and doubling time of H. assulta were shortest for larvae fed artificial diet, intermediate from larvae reared on pepper, and longest from larvae reared on tobacco. We concluded that the artificial diet was the most suitable larval diet of H. assulta followed by pepper, and tobacco.  相似文献   

20.
Vegetation management on levees, especially removal of trees and shrubs, might affect burrowing mammals that are considered threats to levee integrity. We evaluated habitat associations of California ground squirrels (Otospermophilus beecheyi) and Botta's pocket gophers (Thomomys bottae) on levees in the Sacramento Valley to assess the effects of levee vegetation management on these species. Using burrows as an indirect measure of mammal presence, we found that the presence of trees had a negative effect on the occurrence and abundance of ground squirrels on levees, and on the location of their burrowing activities on the levee slope, potentially because visual occlusion caused by tall woody vegetation impedes detection of predators. Similarly, trees had a negative effect on the abundance of pocket gophers on levees and on the location of their burrowing activities on the levee slope, probably because of the effect of tree cover on food availability. The conversion of woodland habitats to grasslands on levees most likely will result in increased occurrence, abundance, or both of ground squirrels and pocket gophers, and thereby increase the potential threat that their burrowing activities pose to levee integrity. © 2012 The Wildlife Society.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号