DIVERSITY, CHARACTERISATION, AND DESCRIPTION OF KNOWN AND NEW PLANT-PARASITIC NEMATODES FROM SOME EXOTIC PLANTS IN BELGIUM Huu Tien Nguyen Student number: 01608112 Promoter(s): Prof. Dr. Bert Wim, Prof. Dr. Wilfrida Decraemer A dissertation submitted to Ghent University in partial fulfilment of the requirements for the degree of International Master of Science in Agro- and Environmental Nematology Academic year: 2016 - 2018 Contents Chapter 1: Molecular and morphological characterisations of a new root-lesion nematode, Pratylenchus n. sp. (Tylenchomorpha: Pratylenchidae) from Belgium ............................................................................................ 1 Materials and methods ..................................................................................................................................... 3 SAMPLING AND NEMATODE EXTRACTION ........................................................................................................... 3 MORPHOLOGICAL CHARACTERISATION .............................................................................................................. 3 MOLECULAR CHARACTERISATION ..................................................................................................................... 4 CLUSTER ANALYSIS ......................................................................................................................................... 6 Results .............................................................................................................................................................. 6 MEASUREMENTS ............................................................................................................................................. 6 DESCRIPTION .................................................................................................................................................. 8 MOLECULAR CHARACTERISATION ................................................................................................................... 11 DIAGNOSIS AND RELATIONSHIPS ..................................................................................................................... 15 TYPE HOST AND LOCALITY ............................................................................................................................. 20 TYPE MATERIAL ............................................................................................................................................ 20 Discussion ....................................................................................................................................................... 20 Acknowledgment ............................................................................................................................................ 23 References ...................................................................................................................................................... 23 Chapter 2: Survival of the tropical root-knot nematodes Meloidogyne incognita (Kofoid & White, 1919) (Chitwood, 1949) Whitehead, 1968 (Nematoda: Meloidogynidae) in Belgium .................................................. 27 Materials and methods ................................................................................................................................... 30 SAMPLING AND NEMATODE EXTRACTION ......................................................................................................... 30 MORPHOLOGICAL CHARACTERISATION ............................................................................................................ 30 MOLECULAR CHARACTERISATION ................................................................................................................... 30 Results ............................................................................................................................................................ 31 SYMPTOMS OF HOST PLANT ............................................................................................................................ 31 MORPHOLOGICAL CHARACTERISATION OF M. INCOGNITA IN BELGIUM ................................................................ 32 MOLECULAR CHARACTERISATION ................................................................................................................... 34 HOST AND LOCALITY ..................................................................................................................................... 39 SPECIMEN VOUCHER ...................................................................................................................................... 39 Discussion ....................................................................................................................................................... 39 Acknowledgement .......................................................................................................................................... 42 References ...................................................................................................................................................... 42 Chapter 3: Description of a new species of Rotylenchus and a Belgian population of Rotylenchus buxophilus (Tylenchomorpha: Hoplolaimidae) ................................................................................................................. 45 Materials and methods ................................................................................................................................... 47 SAMPLING AND NEMATODE EXTRACTION ......................................................................................................... 47 MORPHOLOGICAL CHARACTERISATION ............................................................................................................ 47 MOLECULAR CHARACTERISATION ................................................................................................................... 47 CLUSTER ANALYSIS ....................................................................................................................................... 49 Results ............................................................................................................................................................ 50 Rotylenchus n. sp. ........................................................................................................................................... 50 MEASUREMENTS ........................................................................................................................................... 50 DESCRIPTION ................................................................................................................................................ 51 MOLECULAR CHARACTERISATION ................................................................................................................... 52 DIAGNOSIS AND RELATIONSHIPS ..................................................................................................................... 57 TYPE HOST AND LOCALITY ............................................................................................................................. 63 TYPE MATERIAL ............................................................................................................................................ 63 Rotylenchus buxophilus Golden, 1956 ............................................................................................................. 64 MEASUREMENTS ........................................................................................................................................... 64 MORPHOLOGICAL CHARACTERISATIONS OF ROTYLENCHUS BUXOPHILUS IN BELGIUM ............................................ 65 MOLECULAR CHARACTERISATION ................................................................................................................... 67 REMARKS ..................................................................................................................................................... 68 HOST AND LOCALITY ..................................................................................................................................... 69 VOUCHER SPECIMENS .................................................................................................................................... 69 Discussion ....................................................................................................................................................... 69 Acknowledgment ............................................................................................................................................ 72 References ...................................................................................................................................................... 72 Acknowledgements I would firstly like to express my sincere and profound gratitude to my promoters, Prof. Wim Bert and Prof. Decraemer Wilfrida for their valuable comments, suggestions, and support throughout my study. Their guidance was really important and useful to improve my thesis. And, it was my luck to work under the guidance of leading nematological professors of the world. Their extensive experiences have made me really admire them. I am also very grateful to Marjolein, Dieter, Rolish and everyone in the Nematology Research Unit for giving time, laboratory facilities, and technical support