INTROPICA

9-16

Authors: Alberto Páez-Redondo, Xilena Blanco-Muñoz, Rosa Ospino-Castro

Secamiento foliar progresivo or SFP is a disease Recorded in the late 90s in oil palm plantations in some municipalities of the department of Magdalena. This problem causes a gradual deterioration of plants, and general symptoms caused can be confused with those induced by other sanitary problems. In three crops, the symptoms of disease were characterized with objective to differentiate SFP of other diseases, and so, we can get necessary information for taking the best decision about management of the SFP. Internals and externals symptoms were characterized; were determined evolution of leaves symptoms per days and percentage of roots affected. Externals symptoms were evident only on leaves and they occurred gradually and descendant direction; they were observed initially on leaves levels second, showed yellow zones in any part of foliage similar to a band, but with initiation on apical leaf; after, leaves showed increase of size of yellow bands, and reddish shade and necrotic tissues. A severity scale was adjusted for evaluating external symptoms on leaves, with five levels. The development of foliar symptoms required a greater number of days in the upper levels that the lower levels leaves. In the same order, a greater number of days were necessary for the symptoms evolved from grade 1 to 2 than grade 2 to 3 and 3 to 4, respectively. As the leaves mature, the foliar symptoms are more severe, allowing infer that the problem is progressive and is the result accumulated permanent damage in roots of the plants. In plants with foliar symptoms grade 2, the percentage of damaged roots was 58% on average; those roots showed rotten and rusty zones and roots splited in two or more sites

29 - 42

Authors: Nelson Guillermo Rangel-Buitrago, Blanca Oliva Posada-Posada

A scientific consensus exists regarding the significant impact on the global climate, including changes in rainfall patterns and sea level rise, among others. Although the magnitudes of these changes still are not clear, the analyses of the vulnerability and risk along the littorals represent the first step to design an adaptation plan of the climate change. With this in mind, the selected study area was the District of Cartagena de Indias, Colombian Caribbean Coast. It is located in the coordinates 10°45’N-75°15’W and 10°10’N-75°45’W and its littoral has an approximate length of 370 km. A detailed evaluation of the vulnerability and the risk by erosion along his littoral was carried out, considering physical, social, conservational and heritage aspects. The analysis was made by semiquantitative approximation method, applying relative indexes: geomorphologic unit, width, the slope and ype of beach, degree of exhibition of the coasts to the waves, between others. Initially, the available information was of shoreline retreat, land uses, conservation and heritage. The results showed erosion rates bigger than 3 m year-1 in critical sectors (Playetas and Tierrabomba), between 1994 and 2011, and the land se and local and regional economy were affected. 41% of coastline was classified with low and very low risk, 32.15% with moderate risk, whereas 13.69% and 13.27% had values of high and very high risk respectively. nder climate change conditions, sea level rise and sediment imbalance, the coastal erosion along of the District of Cartagena de Indias will be intensified by the shoreline retreat in a short, medium and long term. The adaptation must be a priority strategy, to being considered ith alternatives of relocation, sustainable protection and littoral zoning to human settlement, land uses and future applications.

53 - 60

Authors: Luis Ruiz, Adriana Vallejo

This work aimed at morphologically identifying nematodes isolated from individuals of Parassi mullet (Mugil incilis) captured in the Cartagena bay and to establish their intensity and prevalence on the rainy season. For that purpose, 378 individuals of Parassi mullet were collected at three sites in the bay between June and November 2009. Then, the collected individuals were taken to the laboratory for dissection and analysis of their visceral cavity. Nematodes isolated from each individual were counted and preserved in 10% formalin, then fixed and clarified. The identification was carried out by optic microscopy and was based on the following morphological characteristics: position of the excretory pore, tail shape, length and shape of the ventricle, and presence, length and position of the anterior and posterior intestinal caecum and of the ventricular appendix. Before clearance, a histological section was performed to observe the shape of the intestinal tract. Nematode parasites belonging to the genera Pseudoterranova and Contracaecum, larval III stage, were found. Based on the entire sample of fish, parasite prevalence was estimated to e between 80% and 100%, while parasitic intensity ranged between 4 and 23 parasites per fish.

69 - 78

Authors: Euler Gallego, Lena Manjarrez, Leidys Herrera, Edgardo José Leal

It was studied the effect of subbituminous coal on growth and pigments concentration of dunaliella salina cultivated in photobioreactor multiple chambers oscillating (FMCO) under open field conditions. Five treatments of CSM (10, 20, 30, 40, 50, 60 mg/L) and a control were performed, each in triplicate. Population growth was assessed by count cell, and the pigment content was performed by spectrophotometric techniques. The results indicated that treatment of 20 mg/L of CSM produced a greater stimulus on microalgae growth with 6.50 ± 0.77 x 106 cel.ml-1, specific growth rate (μ) 0.52 ± 0.03 div/day and duplication time (Td) of 1.33 ± 0.04 days. Also there was a greater increase in total chlorophyll and carotenoids per volume of culture in the logarithmic phase, with 12.6±0.26 and 0.50±0.04mg/ml, respectively. These concentrations show a significant correlation with maximum cell density of D. salina on function to the treatments of CSM with rMDC, chla.tot = 0.918 and with rMDC, carot.tot = 0.919 at a significance level of p<0.01. The positive effect on the growth strain is probably explained by the physical and chemical properties of the carbonaceous material The results demonstrated the feasibility of using this coal as a suitable substrate for the microalgae growth, being an innovative alternative and less costly to obtain important metabolites.

87 - 97

Authors: Luz Adriana Velasco

It was carried out an analysis of each one of the different indices proposed to estimate the reproductive effort in mollusks with the purpose of clarifying its pertinence and determination. Additionally, a synthesis of the various factors affecting the reproductive effort of mollusks as well as the different partitioning strategies of the assimilated energy was performed. Finally, it was examined the usefulness of the reproductive effort determination in the fields of ecology and applied physiology.