We studied the role of Wnt signaling in axis formation during metamorphosis and regeneration in the cnidarian Hydractinia. Activation of Wnt downstream events during metamorphosis resulted in a complete oralization of the animals and repression of aboral structures (i.e. stolons). The expression of Wnt3, Tcf and Brachyury was upregulated and became ubiquitous. Rescue experiments using Tcf RNAi ...

Hooked apex stolons and initial swelling stolons of potato plants were treated with 3 x 10-8 mol l-1 jasmonic acid (JA) to study the effect of this compound on histology, cell expansion and tissue differentiation. In hooked apex stolons, JA application increased the meristem thickness and reduced the length of the leaf primordia, whereas in initial swelling stolons narrowing of the apical regio...

Perturbed colonies of Phenganax parrini and Sarcothelia sp. exhibit migration of symbionts of Symbiodinium spp. into the stolons. Densitometry and visual inspection indicated that polyps bleached while stolons did not. When migration was triggered by temperature, light and confinement, colonies of Sarcothelia sp. decreased rates of oxygen formation in the light (due to the effects of perturbati...

Phloem unloading was studied in potato plants in real time during the early stages of tuberization using carboxyfluorescein (CF) as a phloem-mobile tracer, and the unloading pattern was compared with autoradiography of tubers that had transported (14)C assimilates. In stolons undergoing extension growth, apoplastic phloem unloading predominated. However, during the first visible signs of tuberi...

Intraspecific encounters between colonies of the athecate, colonial hydroid Hydractinia echinata result in contact between mat or stolonal tissues. We have monitored colony ontogeny in five clones of H. echinata and initiated experimental encounters between the two tissue types in both isogeneic and allogeneic combinations. All isogeneic interactions result in fusion, all allogeneic interaction...

Two methods to induce a symptomless infection of crown rot (Phytophthora cactorum) in stolons of three strawberry (Fragaria×ananassa) cultivars were evaluated. Spraying a 10−4 ml zoospore suspension was the most effective method, producing a mean infection rate of 12%. Meristem cultures were subsequently established from all of the inoculated stolons and tested eight weeks later for the presenc...

Many abundant plants, invertebrates, and seaweed are clonal, and this allows the formation of high-density aggregations, foraging, and the placement of modules into new space, and rapid rates of expansion. For these species, population density and rates of expansion are functions of recruitment of asexual modules and post-recruitment vegetative growth and survivorship. In this study, we provide...

As with many colonial animals, hydractiniid hydroids display a range of morphological variation. Sheet-like forms exhibit feeding polyps close together with short connecting stolons, whereas runner-like forms have more distant polyps and longer connecting stolons. These morphological patterns are thought to derive from rates of stolon growth and polyp formation. Here, stolon regression is ident...

Fronds had higher mean caulerpenyne concentration than stolons in Caulerpa prolifera, C. taxifolia and C. racemosa. C. prolifera had higher mean caulerpenyne content w7.29"0.64% caulerpenyne/frond dry weight (DW)x than C. taxifolia (5.47"0.32% caulerpenyne/frond DW) and C. racemosa (0.43"0.07% caulerpenyne/frond DW). C. prolifera had reduced content from May to October in fronds, with no clear ...

By analyzing the growth and development of different types strawberry plants, researchers were able to evaluate interference with horticultural potential cultivar ‘Albion’. The five treatments that have been studied corresponded plants: mini plants in trays young roots, mature roots an initial reduction fertigation, bare preserved by cold. In bags containing coconut fiber, experiment was laid o...