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The islands of the Seychelles, lying in the Indian Ocean 1 800 km south of Sri Lanka and ca. 1500 km east of Africa, are of exceptional biological interest. ~o of the granitic islands, namely Praslin and Curieuse, are home to the plant producing the biggest seed in the plant kingdom, the Lodoicea maldivica (Gmelin) Persoon (Arecaceae). Not only is the seed harvested for sale to tourists, but the sites where it grows are important visitor destinations. The long life cycle and lack of demographic data are major impediments in the present management of the species. Historical information is scattered and to establish baseline information is one key challenge. The few scientific studies undertaken in the past were limited to one population which was automatically identified to be representative without testing this hypothesis. The collation of historical information demanded an in depth research in two archives in Seychelles. All available Annual Reports of the Department of Agriculture from 1884 to 1971 were reviewed and analysed for information related to Lodoicea. In addition reports of visiting scientists and foresters were also reviewed, as much as all locally available historical unpublished reports. Besides the analysis of historical documents, several interviews with retired forestry personnel were carried out. It can be stated that historical information on the size, structure, productivity and health of Lodoicea populations is scattered and incomplete. The historical information collated can not be used to answer the two main questions: have the size and structure of populations been stable or increasing and did the rate of harvesting allow adequate recruitment or not? Also the success of past efforts in restoring and rehabilitating populations can not be evaluated for the same reasons. As a result clear baseline information could not be established. To evaluate the demography and health of the three main populations (vallee de Mai and Fond Ferdinand on Praslin and one population on Curieuse) two survey methods were applied permanent sample plots and trail transects. The combination of the two methods proved to be an effective sampling compromise. The data collected indicate that there is a considerable difference in the growth and appearance of Lodoicea growing on Praslin and Curieuse. The significance of the difference observed in this study needs further research. In addition the data suggest that the population structure of the Lodoicea population on Curieuse is much more natural than in the other two sites. Since the Lodoicea forests on Curieuse differs in structure and appearance ~om the more intensively studied site, the Vallee de Mai, it is concluded that low stature forests represent a part of the natural variation of Lodoicea forest that has been neglected. It is recommended to extend the existing monitoring scheme and include the Curieuse and Fond Ferdinand forests. Besides the survey work eight data collection protocols were developed. There are several agencies involved in the management of the three main populations. The capacity of the management teams in conservation management differs greatly. These protocols are intended to ensure that the data collected by different surveyors as well as collected in the three different populations are comparable in future. The first legal protection considering the Lodoicea was announced by the government in 1979. The Coco de Mer (Management) Decree, was developed as management tool and the nut was declared as a licensable product. A review of the decree was initiated and the findings and recommendation are presented. In the past all main populations were under the direct management of the state. This has changed and the three organisations involved differ in missions and objectives. Consequently the different management practices are analysed and gaps identified.

Date palm (Phoenix dactylifera L.) is a diploid with 18 pairs of chromosomes and an estimated genome size of 658 Mb. It is a dioecious perennial monocot, with a long generation time (a period of 4-5 years until first flowering). Date palm is one of the major fruit crops grown in the Gulf countries and particularly in the Sultanate of Oman. Approximately 250 varieties of date palm are recorded throughout the country with evaluation and characterization based on morphological and reproductive traits (e.g. fruit color, fruit shape and fruit weight). Limited molecular characterization work has been undertaken for date palm germplasm in general and Omani date palm germplasm, in particular. The principal focus of this study was to: investigate the genetic diversity of Omani date palm germplasm and compare it with 'exotic' germplasm, to differentiate between female and male plants at the molecular level and to construct an initial genetic map for date palm. Samples were taken from eight parents of the available Omani date palm controlled crosses (Khalas 4, Khalas 13 male, Um-Alsela, Khori male, Bami, Naghal, Bahlani male, and Khasab) with 90 date palms from the BC1 and F1 populations, from 194 Omani date palm accessions (151 female cultivars and 43 male trees), together with samples from Italy (Sanremo and Bordighera), USDA-ARS, France, Iraq, Libya, Sudan and Iran. The F-statistics analysis showed that the genetic variation between female and male accessions based on random markers was only 2.1 %, while within the broader group of Omani female and male accessions the molecular variation was 97%, suggesting that the Omani female and male accessions have little consistent divergence, compared to the large-scale divergence within Omani germplasm, so male palm have been derived from most genetic origins in Oman. Additionally, the Principal Coordinates Analysis (PCA) and bootstrap consensus phenetic tree showed that the Omani accessions were closely related to each other and there was no clear genetic differentiation between female and male cultivars. A high degree of genetic variation was observed between germplasm from Oman, Italy, USDA-ARS, France, Iraq, Libya, Sudan and Iran as measured by Fst (19.7 %). The PCA showed that the Europe-Africa (Italy, France, Libya and Sudan) accessions are distinguished from West-Asia (Oman, Iraq and Iran) accessions and have their own autochthonous origin, a finding which was strongly validated by bootstrap consensus tree test. A medium density genetic map in date palm was constructed using 53 individuals from BC1 and 30 individuals from F1 populations. The BC1 map consisted of 270 markers (28 SSR and 242 SNP) distributed into 29 linkage groups with total genetic length of 1.486.7 cM, while the F1 map consisted of 591 markers (21 SSR and 570 SNP) distributed into 30 linkage groups with total genetic length of 2,385.6 cM. A total of 25 combined linkage groups were possible by combining both BC1 and F1 maps through common markers. A sex-link marker locus was developed and found to predict a high level of discrimination between male and female date palms among multiple varieties distributed across the wide range of cultivation, with an accuracy of 100% in the Omani crosses, 96% in the broad Omani material and 86% in the broadest date palm germplasm. This marker was also mapped in both BC1 and F1 at 42.8 cM and 4.9 cM in linkage groups 18 and 29, respectively and on combined group 19 at 42.8cM.