References 343 20. J. Zel: Micropropagation of Pinus sylvestris 347 1. Introduction 347 2. Micropropagation from embryos 347 3. Micropropagation from seedling explants 350 4. Conclusions 362 5. Summary 362 References 362 21. M. J. Hutzell and D. J. Durzan: Improved aseptic germination and controlled growth for micropropagation of Douglas fir 367 l. Introduction 367 2. Material and methods 367 3. Results and observations 369 4. Discussion 370 5. Summary 372 References 372 22. D. F. Karnosky, Y Huang and D. I. Shin: Micropropagation of Larix species and hybrids 373 1. Introduction 373 2. Micropropagation from juvenile tissues 373 3. Micropropagation from mature trees 376 4. Potential uses of and research needs for micropropagation 377 5. Summary 380 References 380 23. B. J. Nairn: Commercial micropropagation of radiata pine 383 1. Introduction 383 2. Protocols 386 3. Costs 392 4. Future aspects 393 5. Summary 393 References 394 24. P. S. Rao and T. R. Ganapathi: Micropropagation ofpalms 395 1. Coconut (Cocos nucifera L. ) 395 2. Date palm (Phoenix dactylifera L. ) 400 3. Oil palm (Elaeis guineensis Jacq. ) 405 4. Summary 414 References 415 XI Section III. Tree improvement 423 25. W. J. Libby and M. R. Ahuja: Micropropagation and clonal options in forestry 425 1. Introduction 425 2. Definitions of micropropagation and clonal options 425 3. The selection of genotypes for micropropagation 426 4. The testing of micropropagated clones 427 5. The genetics of clones 429 6. Uses 433 7.