Patterns of wing size variation in seeds of the lily Cardiocrinum cordatum (Liliaceae)

We examined the patterns of variation in wing-loading and its related characteristics in Cardiocrinum cordatum to clarify the factors that determine the variation in seed dispersal ability in this species. The square root of wing-loading of a seed of a plant was not significantly correlated with basal stem diameter of a plant, indicating that large plants did not necessarily produce seeds with high dispersal ability. This result was inconsistent with the hypothesis that large plants produce seeds with high dispersal ability to avoid high mortality of seeds and seedlings in the vicinity of the parents. On the other hand, the square root of wing-loading of a seed of a fruit was negatively dependent on seed number of a fruit. Thus, many-seeded fruits produced seeds with high dispersal ability. This was because the projected surface area per seed was large in large fruits and large fruits contained large numbers of seeds. The cost per seed of producing fruit structures was small for many-seeded fruits. Thus, high dispersal ability of seeds in many-seeded fruits may be a result of an effective resource allocation pattern in which a high proportion of resources are allocated to those many-seeded fruits, enabling seeds to develop large wings and thus reducing the structural cost of fruits per seed.     

紫堇属和钻地风属植物二新异名

将白花刻叶紫堇(Corydalis incisa (Thunb.)Pers. var. alba S. Y. Wang)作为新异名归并入刻叶紫堇(C. incisa (Thunb.)Pers.);将心叶钻地风(Schizophragma integrifolium Oliv. f. cordatumS. Y. Wang)作为新异名归并入秦榛钻地风(S. corylifolium chun).     

Scaling the leaf length-times-width equation to predict total leaf area of shoots

Background and AimsAn individual plant consists of different-sized shoots, each of which consists of different-sized leaves. To predict plant-level physiological responses from the responses of individual leaves, modelling this within-shoot leaf size variation is necessary. Within-plant leaf trait variation has been well investigated in canopy photosynthesis models but less so in plant allometry. Therefore, integration of these two different approaches is needed.MethodsWe focused on an established leaf-level relationship that the area of an individual leaf lamina is proportional to the product of its length and width. The geometric interpretation of this equation is that different-sized leaf laminas from a single species share the same basic form. Based on this shared basic form, we synthesized a new length-times-width equation predicting total shoot leaf area from the collective dimensions of leaves that comprise a shoot. Furthermore, we showed that several previously established empirical relationships, including the allometric relationships between total shoot leaf area, maximum individual leaf length within the shoot and total leaf number of the shoot, can be unified under the same geometric argument. We tested the model predictions using five species, all of which have simple leaves, selected from diverse taxa (Magnoliids, monocots and eudicots) and from different growth forms (trees, erect herbs and rosette herbs).Key ResultsFor all five species, the length-times-width equation explained within-species variation of total leaf area of a shoot with high accuracy (R² > 0.994). These strong relationships existed despite leaf dimensions scaling very differently between species. We also found good support for all derived predictions from the model (R² > 0.85).ConclusionsOur model can be incorporated to improve previous models of allometry that do not consider within-shoot size variation of individual leaves, providing a cross-scale linkage between individual leaf-size variation and shoot-size variation.     

Resistance of the heart sea urchin Echinocardium cordatum (Echinoidea: Spatangoida) to extreme environmental changes

The ability to survive under extreme environmental conditions was studied in the adults of the heart sea urchin Echinocardium cordatum (Pennant). At seawater temperatures of 13.3 to 14.8°C and salinity of 33.2–33.4‰, being devoid of the possibility to burrow into the sand or eat, some sea urchins died on day 5 and all individuals had perished by the end of day 8. At a temperature of 19°C, the salinity tolerance range of adults was limited to 33–28‰. Only 30 to 20% of sea urchins transferred to a solid substrate survived for 7 days at a salinity of 33 to 24‰, but all of them perished toward the end of day 8.     

峨眉双蝴蝶的胚胎学研究

首次报道了峨眉双蝴蝶Ｔｒｉｐｔｅｒｏｓｐｅｒｍｕｍ ｃｏｒｄａｔｕｍ（Ｍａｒｑ．）Ｈ．Ｓｍｉｔｈ的胚胎学特征,研究结果用以讨论双蝴蝶属的系统演化关系。主要研究结果如下：花药四室;药壁发育为双子叶型;绒毡层属单型起源,细胞具单核,属腺质型绒毡层,药隔处的绒毡层细胞形成类胎座,其余部位的绒毡层细胞仍为一层细胞;在花药成熟时,花药的药室内壁纤维状如厚且柱状伸长,表皮细胞减缩退化,纤维状加厚不明显。成熟花     

Fast isolation of microsatellite loci of very diverse repeat motifs by library enrichment in echinoderm species,Amphipholis squamata and Echinocardium cordatum

We conceived a microsatellite enrichment protocol in which probes of several repeat motifs are mixed during the whole procedure. The repeats found generally differed from those of the probes and were very diverse, from mononucleotides to pentanucleotides. We tested several modifications with alternative: (i) digestion/ligation buffers; (ii) polymerases; and (iii) purification methods. The simplest methods always worked as well as classical ones or even better, resulting in probably the simplest protocol for isolating microsatellites of diverse motifs from genomes with low microsatellite frequency. The proportion of positive clones, polymorphism levels and cross‐specific amplification of microsatellite loci significantly vary between species.