The secret life of the giant Australian cuttlefish Sepia apama (Cephalopoda): Behaviour and energetics in nature revealed through radio acoustic positioning and telemetry (RAPT)

Sepia apama were tagged with acoustic transmitters and monitored on their native House Reef, Boston Bay, South Australia, with a radio acoustic positioning telemetry (RAPT) system. Cuttlefish were tagged with position-only and intra-mantle jet pressure transmitters. New data analyses were developed to handle problem data that arise with an uneven reef environment. Maximum range for the cuttlefish varied from 90 m to 550 m. Cuttlefish home range was between 5300 m² and 23,700 m². S. apama were found to be diurnal as average distance travelled was higher in the day than at night, and cuttlefish were active for 32 days, but only 18 nights. After the cuttlefish settled into reef crevices, activity spectrum and positioning analysis showed foraging behaviour at only 3.7% per day and 2.1% per night. Cuttlefish were found to spend more than 95% of the day resting, which suggests that their bioenergetics are more akin to those of octopus than of squid. The cuttlefish combination of predator avoidance, efficient foraging and quiescent lifestyle allows energy to be channelled into growth and fulfillment of the live-fast-die-young cephalopod philosophy.     

影响芋茎尖培养中脱毒和快速繁殖的几个生理因素

以3个芋品种（‘石川早生’、‘虾籽芋’、‘叶用芋）球茎茎尖为外植体,进行脱病毒和快繁的结果表明,外植体表面灭菌的最佳方法是剥鳞片→乙醇→新洁尔灭→剥幼叶→氯化汞;适宜茎尖分化的培养基为MS＋1．0-2．0mg·L^-16-BA＋0．2mg·L^-1 NAA。生物学方法和电镜观察显示：连续3代0．5-0．7mm茎尖剥离培养对芋花叶病毒（DMV）的脱毒率达100％。在培养基MS＋0．2mg·L^-1 NAA中,适量添加6-BA和TDZ,三品种芋的试管苗增殖效果好;附加KT,试管苗生长健壮且利于生根：添加20-100mg·L^-1的精胺（spm）,可促进不定芽的发生,与KT配合使用可促使继代增殖和成苗一步完成。完整植株在草炭土：蛭石=1：1的基质中,移栽成活率超过97％,且苗生长健壮。     

Perception of edges and visual texture in the camouflage of the common cuttlefish, Sepia officinalis

The cuttlefish, Sepia officinalis, provides a fascinating opportunity to investigate the mechanisms of camouflage as it rapidly changes its body patterns in response to the visual environment. We investigated how edge information determines camouflage responses through the use of spatially high-pass filtered 'objects' and of isolated edges. We then investigated how the body pattern responds to objects defined by texture (second-order information) compared with those defined by luminance. We found that (i) edge information alone is sufficient to elicit the body pattern known as Disruptive, which is the camouflage response given when a whole object is present, and furthermore, isolated edges cause the same response; and (ii) cuttlefish can distinguish and respond to objects of the same mean luminance as the background. These observations emphasize the importance of discrete objects (bounded by edges) in the cuttlefish's choice of camouflage, and more generally imply that figure-ground segregation by cuttlefish is similar to that in vertebrates, as might be predicted by their need to produce effective camouflage against vertebrate predators.     

木薯雌雄花分化形态结构观察及生理调控研究

本研究以木薯品种新选048为试验材料,观察和测定木薯花分化各时期的形态结构、内源激素及碳氮化合物含量,并开展木薯雌雄花分化的外源激素调控研究,揭示木薯花分化规律,初步探究木薯花分化的生理机制.试验结果表明:木薯从花芽分化开始到完成开花的全过程需要30 d,分化出的花序主要有全雄花序和雌少雄多花序两种类型,木薯性别分化前...     

4种生态因子对虎斑乌贼幼体生长与存活的影响

旨在研究温度、盐度、饵料种类、投饵量对虎斑乌贼（Sepia pharaonis）幼体生长与存活率的影响,以确定其生长发育的最佳生态条件,为人工育苗提供理论依据。在室内控制条件下,采用单因子试验研究了不同温度（18、21、24、27、30和33℃）、不同盐度（18、21、24、27、30和33）、不同饵料种类（虾糜、活糠虾、卤虫无节幼体、桡足类、死糠虾、虾糜＋强化卤虫后无节幼体、强化卤虫后无节幼体）、活糠虾不同投饵量（0、2、4、6、8和10 g/d）对虎斑乌贼幼体生长发育的影响。结果显示：不同温度对虎斑乌贼幼体生长影响显著（P〈0.05）,最适温度为24-27℃,在最适温度下,存活率为84.4%-91.1%,特定生长率为4.82%-6.13%,存活率（y）与温度（x）的函数关系为y=-0.15x3＋30.637x-447.002（r2=0.923）。幼体适宜盐度为24-33,最适盐度为27,在最适盐度条件下,其存活率为（90.0±5.29）%,特定生长率为（3.71±0.34）%。投喂7种开口饵料,以活糠虾效果最佳,存活率为（96.7±2.94）%,特定生长率为（3.77±0.23）%;强化卤虫后无节幼体效果次之,存活率为（95.6±2.31）%,特定生长率为（2.54±0.15）%,其余各组培养效果均不理想。投喂活糠虾,随着投饵量的增加,其存活率随之提高,摄食量（y）与个体重（x）的回归方程为y=0.227x-0.063（r2=0.921）。     

Production of stably transformed cassava plants via particle bombardment

 A novel protocol, based on biolistics and regeneration via organogenesis, was developed for genetic transformation of cassava (Manihot esculenta Crantz). The in vitro performance of cassava cultivars CMC40, MPer183 and MCol22 was evaluated, and the regeneration protocol was modified to improve shoot production from explants for transformation experiments. Somatic cotyledons were used as a target tissue in the transformation experiments using the Particle Inflow Gun and a plasmid containing the uidA gene in transient assays. The effect of different parameters for particle bombardment efficiency, including the amount of DNA used, the flying distance of the projectiles and the pre- and post-plasmolysis time of the target tissue, was evaluated and the conditions were partially optimised. Stably transformed cassava plants of cvs. MCol22 and TMS60444 were produced using the partially optimised conditions and two different vector constructs carrying the hpt gene as the selectable marker. The selection protocol was optimised further, and a rooting test was developed for screening the regenerants for antibiotic resistance to reduce the number of escapes obtained after primary selection. The production of stably transformed cassava lines and the expression of the transgenes was verified by Southern blot analysis and RT-PCR. Received: 10 December 1999 / Revision received: 12 January 2000 / Accepted: 7 February 2000     

木薯离体培养与快速繁殖

选取3个木薯品种的腋芽作为外植体,分别接种于MS基本培养基上进行离体培养及快速繁殖。结果表明, 6-BA不同浓度对木薯品种不定芽诱导效果不一,在MS+6-BA 0.5~1.0mg/L中,3个品种均可诱导产生幼芽;在MS+6-BA 3.0mg/L中,3个品种的幼芽诱导率高达100%;MS+6-BA 3.0mg/L+NAA 0.1mg/L对继代效果较好;MS+NAA 0.1mg/L对生根效果最佳。     

A Calcium/Calmodulin-Dependent Nitric Oxide Synthase, NMDAR2/3 Receptor Subunits, and Glutamate in the CNS of the Cuttlefish Sepia officinalis

Chemical, biochemical, and immunohistochemical evidence is reported demonstrating the presence in the brain of the cuttlefish Sepia officinalis of a Ca2+-dependent nitric oxide synthase, NMDAR2/3 receptor subunits, and glutamate, occurring in neurons and fibers functionally related to the inking system. Nitric oxide synthase activity was concentrated for the most part in the cytosolic fraction and was masked by other citrulline-forming enzyme(s). The labile nitric oxide synthase could be partially purified by ammonium sulfate precipitation of tissue extracts, followed by affinity chromatography on 2',5'-ADP-agarose and calmodulin-agarose. The resulting activity, immunolabeled at 150 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis by antibodies to rat neuronal nitric oxide synthase, depended on NADPH and tetrahydro-L-biopterin, and was inhibited by N(G)-nitro-L-arginine. NMDAR2/3 subunit-immunoreactive proteins migrating at 170 kDa could also be detected in brain extracts, along with glutamate (whole brain: 0.32 +/- 0.03 micromol of glutamate/mg of protein; optic lobes: 0.22 +/- 0.04; vertical complex: 0.65 +/- 0.06; basal lobes: 0.58 +/- 0.04; brachial lobe: 0.77 +/- 0.06; pedal lobe: 1.04 +/- 0.08; palliovisceral lobe: 0.86 +/- 0.05). Incubation of intact brains with 1.5 mM glutamate or NMDA or the nitric oxide donor 2-(N,N-diethylamino)diazenolate-2-oxide caused a fivefold rise in the levels of cyclic GMP, indicating operation of the glutamate-nitric oxide-cyclic GMP signaling pathway. Immunohistochemical mapping of Sepia CNS showed specific localization of nitric oxide synthase-like and NMDAR2/3-like immunoreactivities in the lateroventral palliovisceral lobe, the visceral lobe, and the pallial and visceral nerves, as well as in the sphincters and wall of the ink sac.     

芋侧球茎发生发育的形态学机理

观察了魁芋和多子芋腋芽、侧球茎发生发育的形态学变化规律,分析了主球茎顶芽和不同发育期腋芽中蛋白质的组成。结果表明,魁芋每一叶轮上腋芽数目为１;多子芋为３或３个以上,其中一个体积较大。魁芋侧球茎发育初期伸长的速度大于增粗,首先形成圆柱型,然后顶端膨大形成体积很小的侧球茎。多子芽腋芽伸的同时茎部明显变粗,首先形成圆锥型,然后发育成品种特有的形状。根据发育进程将腋芽发育分成ＡＢ１－ＡＢ９个时期,将主球茎     

Karyotype Evidence for Distinguishing Between Hemerocallis esculenta and H. middendorfii

Hemerocallis dumortierii, H. esculenta and H. middendorfii were considered to belong to a biological complex, and were treated as different varieties of the same species, H. dumortierii. The present authors observed and compared the karyotypes of H. esculenta and H. middendorfii. Two plant samples for each of the species were studied. One sample of H. esculenta was from Wuán County, Hebei Province, at an altitute of 1000 m, the other from Shennongjia, Hubei Province, altitute 2100 m. The two samples of H. middendorfii were respectively from Antu County, at an altitute of 700 m, and Tonghua, altitute 500 m, in Jilin Province. The karyotypes are 2n＝2x=22=12m+8sm+2T for H. esculenta, while 2n＝2x＝22=10m+6sm+4st+2T for H. middendorfii. The karyotypical difference between the two taxa was obviously not intraspecific but interspecific. Based on the karyotype data as well as the morphological and phytogeographical data available, it is considered that H. esculenta and H. middendorfii should be recognized as different species, instead of different varieties of the same species as in literature, and that H. mid-dendorfii is more advanced than H. esculenta.