金斑蝶生物学与规模化饲养的初步研究

记述了金斑蝶Danaus chrysippus chrysippus(Linnaeus)的形态特征、生物学特性与规模化饲养的方法.该蝶在海南尖峰岭地区全年发生、世代重叠,1年发生15代左右,完成1个世代冬季需29～37d,夏季14～18d.成虫抗逆性与生命力强,耐高温,嗜食的寄主植物有马利筋Asclepias curassavica L.和牛角瓜Calotropis gigantean(L).金斑蝶色彩艳丽、飞翔姿态缓慢优美,宜在生态蝴蝶园与喜庆等场合放飞,良好的生态环境是金斑蝶规模化饲养成功的关键,而幼虫饲养是它规模化饲养的重要环节.成虫卵散生,幼虫5龄,初孵幼虫宜室外套网袋饲养,5龄后期用塑料盆室内饲养并使之化蛹于盆盖上,将盆盖挂入羽化室内,通过空调和喷雾装置温度控制在25～28℃,湿度控制在60～80%,使蛹能正常发育和羽化.     

施氮肥对落叶松和水曲柳人工林土壤动物群落的影响

土壤动物对环境变化反应敏感, 全球变化导致土壤氮(N)有效性增加将影响土壤动物群落结构和功能。本文以落叶松(Larix gmelinii)和水曲柳(Fraxinus mandshurica)人工林为研究对象, 通过施肥处理, 在不同季节和土层取样, 研究土壤N有效性增加对土壤动物的数量、类群数和不同功能团的影响。结果表明: (1) 施肥影响两林分土壤动物密度, 导致当年密度增加, 翌年则下降, 这种先增加后降低的趋势在不同土层中均表现出来; (2) 施肥增加了两林分土壤动物类群数, 其中落叶松林分从34类增加到43类, 水曲柳林分从43类增加到48类; (3) 施肥改变了两林分不同食性土壤动物的密度, 腐食性土壤动物数量降低、植食性数量增加、捕食性数量变化不明显。这些结果说明: 土壤N有效性增加显著影响两林分土壤动物群落结构, 可能改变地下碳分配格局和养分循环过程。     

Growth, senescence and water use efficiency of spring oilseed rape (Brassica napus L. cv. Mozart) grown in a factorial combination of nitrogen supply and elevated CO2

Atmospheric CO₂ enrichment is expected to affect the resource use efficiency of C3 plants with respect to water, nutrients and light in an interactive manner. The responses of oilseed rape (OSR) to elevated CO₂ have not much been addressed. Since the crop has low nitrogen use efficiency, the interactive effects of CO₂ enrichment and nitrogen supply deserve particular attention.Spring OSR was grown in climate chambers simulating the seasonal increments of day length and temperature in South-Western Germany. Three levels of N fertilisation representing 75, 150 and 225 kg ha⁻¹ and two CO₂ concentrations (380 and 550 μmol mol⁻¹) were used to investigate changes in source-sink relationships, plant development and senescence, water use efficiency of the dry matter production (WUE_prod.), allocation patterns to different fractions, growth, yield and seed oil contents. Seven harvests were performed between 72 and 142 days after sowing (DAS).Overall, plant performance in the chambers was comparable to the development under field conditions. While CO₂ responses were small in the plants receiving lowest N-levels, several significant N × CO₂ interactions were observed in the other treatments. Increasing the N availability resulted in longer flowering windows, which were furthermore extended at elevated CO₂ concentrations. Nevertheless, significantly less biomass was allocated to reproductive structures under elevated CO₂, while the vegetative C-storing organs continued to grow. At the final harvest shoot mass of the CO₂ exposed plants had increased by 9, 8 and 15% in the low, medium and high N treatments. Root growth was increased even more by 17, 43 and 33%, respectively and WUE_prod. increased by 23, 42 and 35%. At the same time, seed oil contents were significantly reduced by CO₂ enrichment in the treatments with ample N supply.Obviously, under high N-supply, the CO₂ fertilisation induced exaggerated growth of vegetative tissues at the expense of reproductive structures. The interruption of source-sink relationships stimulated the formation of side shoots and flowers (branching out). While direct effects of elevated CO₂ on flowering can be excluded, we assume that the increased growth under high N and CO₂ supply created nutrient imbalances which hence affected flowering and seed set.Nevertheless, the final seed macronutrient concentrations were slightly increased by elevated CO₂, indicating that remobilisation of nutrients from the sources (leaves) to the sinks (seeds) remained effective. These findings were supported by the lower nitrogen concentrations in senescing leaves and probably increased N remobilisation to other plant parts under elevated concentrations of CO₂. All the same, CO₂ enrichment caused a decline in seed oil contents, which may translate into a reduced crop quality.     

Plectranthus: A plant for the future?

The genus Plectranthus (Lamiaceae) is a significant, prolific and extensively used genus in southern Africa. It plays a dominant role in both horticulture and traditional medicine. Some 12 species are documented for their use in treating ailments by various indigenous peoples of southern Africa. It is a firm favourite in gardens and Plectranthus has been bred to further utilise the remarkable diversity of indigenous South African wildflowers with amenity horticultural potential. Although previously subjected to both horticultural (Van Jaarsveld, 2006) and ethnobotanical (Lukhoba et al., 2006) review, Plectranthus is a genus with economic potential in various sectors, and this article aims to review this potential of southern African species.     

Seasonal variation in nutritional characteristics of the diet of greater white-fronted geese

We studied diet and habitat use of greater white-fronted geese (Anser albifrons) from autumn through spring on their primary staging and wintering areas in the Pacific Flyway, 1979–1982. There have been few previous studies of resource use and forage quality of wintering greater white-fronted geese in North America, and as a consequence there has been little empirical support for management practices pertaining to habitat conservation of this broadly distributed species. Observations of >2,500 flocks of geese and collections of foraging birds revealed seasonal and geographic variation in resource use reflective of changes in habitat availability, selection, and fluctuating physiological demands. Autumn migrants from Alaska arrived first in the Klamath Basin of California and southern Oregon, where they fed on barley, oats, wheat, and potatoes. Geese migrated from the Klamath Basin into the Central Valley of California in late autumn where they exploited agricultural crops rich in soluble carbohydrates, with geese in the Sacramento Valley feeding almost exclusively on rice and birds on the Sacramento–San Joaquin Delta primarily utilizing corn. White-fronted geese began their northward migration in late winter, and by early spring most had returned to the Klamath Basin where 37% of flocks were found in fields of new growth cultivated and wild grasses. Cereal grains and potatoes ingested by geese were low in protein (7–14%) and high in soluble nutrients (17–47% neutral detergent fiber [NDF]), whereas grasses were low in available energy (47–49% NDF) but high in protein (26–42%). Greater white-fronted geese are generalist herbivores and can exploit a variety of carbohydrate-rich cultivated crops, likely making these geese less susceptible to winter food shortages than prior to the agriculturalization of the North American landscape. However, agricultural landscapes can be extremely dynamic and may be less predictable in the long-term than the historic environments to which geese are adapted. Thus far greater white-fronted geese have proved resilient to changes in land cover in the Pacific Flyway and by altering their migration regime have even been able to adapt to changes in the availability of suitable forage crops. © 2010 The Wildlife Society.     

葡萄园果蝇的发生及综合防治研究进展

果蝇因种类多、分布广、寄主广、繁殖力强,世代历期短,近年已成为葡萄的重要害虫之一。葡萄果蝇幼虫不仅蛀食果实,导致果实逐渐软化以致变褐色,还能导致微生物的二次侵染,诱发酸腐病,严重影响葡萄的品质和产量。现已发现危害葡萄的果蝇有7种,其中以黑腹果蝇为优势种,其次为斑翅果蝇和叔白颜果蝇。在山东地区,7月初是斑翅果蝇和叔白颜果蝇的发生高峰期,而黑腹果蝇发生高峰期为8-9月上旬。就不同葡萄品种来说,黑腹果蝇成虫对4个葡萄品种巨峰、马奶、无核白和红提的嗜好程度无显著差异,幼虫对红提的嗜好程度显著高于巨峰、马奶和无核白;斑翅果蝇和叔白颜果蝇对于金手指等早熟品种以及果皮较薄的葡萄品种具有更强的趋性。本文依据葡萄园主要果蝇的种类、生物特征、生活习性、发生规律和危害习性,并从农业防治、物理防治、化学防治和生物防治等方面总结分析了其综合防治措施,以期为葡萄园果蝇的可持续控制提供理论和技术支持。     

葎草雌雄植株开花物候和花器官对干旱的响应差异

摘要：以蓓草（Humulusscandens）为实验材料,在控制土壤水分的条件下探究干旱对雌雄异株植物开花物候和花器官形态的影响,结果表明：干旱胁迫将导致蓰草雌雄种群花期提前．花期持续时间延长,雌花将比雄花提早开放;干旱胁迫下雄花的花序轴长、花序轴直径和花药粒径长均分别显著减小24．81％。29．07％和5．14％（P〈0．001,P=0．003,P=0．024）,花粉活力和花粉含量显著下降：干旱胁迫导致雌花的花序轴长、柱头长度和花序的平均花数量显著增大9．78％,70．62％和57．04％（P=0．039．P〈0．001．P〈0．001）;干旱胁迫下种子粒径长、种子粒径宽、种子单粒重和种子千粒重分别显著下降12．12％、12．59％、43．43％和15．38％（显著度水平均为P〈0．001）;干旱胁迫下雌雄植株的地上部分生物量均显著降低（P=0．002,P=0．020）,且雌株的生殖投入在干旱胁迫下显著高于雄株（P=0．049）。研究结果表明了蓰草雌雄植株开花物候及花器官对干旱的响应明显不同。与雄株相比．雌株在干旱胁迫下增加了生物量向生殖器官的分配,从而最大程度地减轻胁迫对其繁殖能力的影响。     

Foraging ecology and niche overlap in pygmy (Kogia breviceps) and dwarf (Kogia sima) sperm whales from waters of the U.S. mid‐Atlantic coast

A complementary approach of stomach content and stable isotope analyses was used to characterize the foraging ecology and evaluate niche overlap between pygmy (Kogia breviceps) and dwarf (K. sima) sperm whales stranded on the U.S. mid‐Atlantic coast between 1998 and 2011. Food habits analysis demonstrated both species were primarily teuthophagous, with 35 species of cephalopods, and 2 species of mesopelagic fishes represented in their overall diets. Pianka's Index of niche overlap suggested high overlap between whale diets (O_n = 0.92), with squids from the families Histioteuthidae, Cranchidae, and Ommastrephidae serving as primary prey. Pygmy sperm whales consumed slightly larger prey sizes (mean mantle length [ML] = 10.8 cm) than dwarf sperm whales (mean ML = 7.8 cm). Mean prey sizes consumed by pygmy sperm whales increased with growth, but showed no trend in dwarf sperm whales. Significant differences were not detected in δ¹⁵N and δ¹³C values of muscle tissues from pygmy (10.8‰ ± 0.5‰, ?17.1‰ ± 0.6‰), and dwarf sperm whales (10.7‰ ± 0.5‰, ?17.0‰ ± 0.4‰), respectively. Isotopic niche widths also did not differ significantly and dietary overlap was high between the two species. Results suggest the feeding ecologies of the pygmy and dwarf sperm whales are similar and both species occupy equivalent trophic niches in the region.     

Evidence of genetic influence on the flowering pattern of Ficus microcarpa

Flowering patterns result from the interactions between genetic and environmental factors. While the genetic basis for flowering time variation in commercial plants is often well understood, few studies have been conducted to investigate these patterns in plants without economic importance. Ficus microcarpa is a commonly introduced horticultural fig tree. Asynchrony in syconium development and the initiation, frequency, and size of crops may affect its fitness as well as the success of mutualism with its pollinating wasps. In order to identify genetically determined patterns in the flowering traits in F. microcarpa, a 14-month census was taken on the flowering characteristics of 28 trees growing in close proximity along an urban street in Taipei, Taiwan. Weekly surveys were taken on 7 characteristics: crop number, syconia per branch, crop asynchrony, as well as flowering onset and seed development duration for both the spring and summer crops. Post-census genotyping at microsatellite loci distinguished 16 genetic groups (5 clonal groups and 11 non-clone trees). All crop characteristics presented higher variation across different genotype groups than within groups except for seed development duration. We found no evidence of adjacency effects or spatial auto-correlation of flowering traits. The study offers the first evidence of genetic variations in the flowering patterns in a species of Ficus. These findings lend insight into the adaptive characteristics that potentially facilitate the local establishment of F. microcarpa in new locations.