Annual Research & Review in Biology

The sea cucumber Holothuria scabra has a high commercial value and a great potential to be cultivated. A thorough feeding strategy is needed to overcome juvenile rearing technique constraints. Stable isotope analysis can be used for determining diet sources of sea cucumbers that play a role as deposit feeders. This study aims to determine suitable diet sources and elucidate the potential of organic matter assimilation of H. scabra by combining three different mixed diets including 10% seagrass Enhalus acoroides bulk, 45% grass Pennisetum purpureum and 45% of cow feces (diet A); 20% seagrass E. acoroides, 40% grass P. purpureum and 40% of cow feces (diet B) and 33% seagrass E. acoroides, 33% grass P. purpureum and 33% cow feces (diet C) and identifying the fecal pellet isotopic properties and compare it to the diet sources and the surrounding sediment. Stable isotope signature of H. scabra and its prospected diet sources, altogether with sediments and fecal pellets were plotted in a conservative bi-plot δ¹³C and δ¹⁵N. The isotopic value of fecal pellets and diet sources indicate a low assimilation rate, the organic matter contained in the sediment is similar to that of the diet sources. Sea cucumber feeds the bulk of the sediment and the detritus of the diet sources and then assimilates the organic matter as soon as the bulk enters the intestine. Due to the low assimilation rates, we suggest for the mariculture of H. scabra that the food should be homogenised and then mixed into the sediment, where the sea cucumber is cultured. 

Aims: To investigate the physiological, leaf gas exchange and quality of Centella asiatica (pegaga) under different nitrogen fertilization rates.

Study Design: Centella asiatica were exposed to four different nitrogen fertilization rates (0, 50, 100, 150 kg/ha) using urea (46% N) as nitrogen sources. The experiment was conducted in a randomized complete block (RCBD) design with three replications. Each treatment consisted of eight plants making the total of plants used in this study is 96 plants.

Place and Duration of Study: Department of Biology, Faculty of Science, Universiti Putra Malaysia From May 2016-June 2016.

Methodology: The growth parameters measured include total leaves numbers, leaf area, total chlorophyll content and total plant biomass. The carbon assimilation parameters were measured using LICOR 6400 XT Portable Photosynthesis System i.e net photosynthesis (A), Transpiration rate (E) and water use efficiency (WUE). Total phenolic and flavonoids contents from the leaves extracts were measured using Folin-Ciocalteu reagents.

Results: The growth parameters such as leaves number, chlorophyll content, leaf area and total biomass were significantly influenced by nitrogen fertilization (P≤ 0.05), However, there were no significant difference observed between 50, 100 and 150 kg N/ha suggesting that 50 kg N/ha was the efficient rates to apply to enhance the growth of this plant. Meanwhile, the net photosynthesis (A) and water use efficiency (WUE) were enhanced with the increasing rate of nitrogen from 0>150 kgN/ha. The production of total phenolics and flavonoids was found to be highest under 100 kg/ha. The harvest index of total phenolics also showed the applications of 100 kg/ha gave the highest harvest index compared to the other nitrogen treatments.

Conclusion: This study indicated growth and carbon assimilation parameters were enhanced under higher nitrogen fertilization and production of secondary metabolites was decreased with high rates of nitrogen. The recommended nitrogen fertilization for C. asiatica was at 100 kg N /ha, where it obtained the highest harvest index.

Fungal decay of yam (Dioscorea alata) popularly known as water yam bought from Nsukka Markets in Nigeria was investigated for the fungi responsible for postharvest rot of tubers in storage. The tubers were used to isolate and identify fungal species that cause rot and deterioration of tubers in storage.  A total of seven fungi namely Botryodiplodia theobromae, Aspergillus sp, Aspergillus niger, Fusarium sp^a, Fusarium sp, Penicillium sp and Trichoderma sp were isolated from healthy or sound tubers. Pathogenicity test was done and proved for all the isolates with Botryodiplodia theobromae and Penicillium sp implicated as the most pathogenic while Trichoderma sp was the least pathogenic. Inoculated tubers were examined and the nature of the rot varied with the pathogens.Fungi

The present study was designed to develop the prediction equations for 305 days fat corrected milk yield on the basis of part periods milk yield, milk component and conformation traits of multi-genotype cows. Artificial Neural Network model had the best prediction accuracy across varying environments, though Genetic Function Algorithm had the overall best adequacy for fat corrected milk yield predictions (FCM305d=1036.1-98.3RP+22FY+15.92UC-0.07RUH; Adj R²=0.997; RMSE=30.07; BIC=1997.28).

Aims: The gastrointestinal tract is one of the most important organs of the human body and is vulnerable to different diseases. Available drugs often have low efficacy or are associated with many adverse effects. Therefore, alternative drugs are necessary to treat gastrointestinal complications. This study intended to identify medicinal plants in the Western Middle Atlas, Morocco, that can affect gastrointestinal disorders.

Place and Duration of Study: Field studies were carried out approximately over a period of two years (2013-2014).

Methodology: During the field trips, the information was collected through interviews, including various data obtained from local healers and traditional medicine men, herbalists, shepherds, patients and elderly persons.

Results: A total of 58 medicinal plants, grouped in 30 taxonomic families and 55 genera were identified. In addition, their popular uses, the part or parts employed, form of use and their biological activity are described. Lamiaceae was the most dominant family reported to be used for the treatment of gastrointestinal diseases (9 species). Among all the plant parts leaves and seeds were the most preferred plant parts used by the informants. Decoction and powder were the most popular form of treatment used. The four main disorders cured by the plants are: Stomachache/Stomach pain (39.65%), diarrhoeas (22.41%), abdominal pain (17.24%) and bowel disorders (17.24%).

Conclusion: This study aims at emphasizing the profound importance of investigating those species of plants that have not been the subject of any pharmacological study, in spite of existing reports on their traditional use.