1. Studies on maturity, yield, under water weight and some other characters of potato progenies

   • B. Maris

   OriginalPaper Pages: 297 - 319

2. Incompatibility as a new method for identification of pyrethrum clones

   • J. G. Brewer
   • J. E. Parlevliet

   OriginalPaper Pages: 320 - 325

3. The inheritance of resistance to Cucumis virus 1 in cucumber (Cucumis sativus L.)

   • E. Kooistra

   OriginalPaper Pages: 326 - 332

4. Mutation breeding of Streptocarpus

   • C. Broertjes

   OriginalPaper Pages: 333 - 339

5. The importance of two-seeded pods in red clover (Trifolium pratense L.)

   • J. Dijkstra

   OriginalPaper Pages: 340 - 351

6. Pre-determination of survival rate of apple and pear scions after X-ray treatment

   • T. Visser
   • D. P. De Vries
   • J. J. Verhaegh

   OriginalPaper Pages: 352 - 354

7. Allopolyploidization of autopolyploids I. Possibilities and limitations

   • J. Sybenga

   OriginalPaper Pages: 355 - 371

8. Interspecific hybrids in the genus Elaeis I. crossability, cytogenetics and fertility of F₁ hybrids of E. guineensis x E. oleifera

   • J. J. Hardon
   • G. Y. Tan

   OriginalPaper Pages: 372 - 379

9. Interspecific hybrids in the genus Elaeis II. vegetative growth and yield of F₁ hybrids E. guineensis x E. oleifera

   • J. J. Hardon

   OriginalPaper Pages: 380 - 388

10. Effect of temperature on the occurrence of male sterility in onion (Allium cepa L.)

    • Q. P. Van Der Meer
    • J. L. Van Bennekom

    OriginalPaper Pages: 389 - 394

11. The inheritance of frost resistance and flowering response in broccoli (Brassica oleracea var. Italica)

    • J. C. Bouwkamp
    • S. Honma

    OriginalPaper Pages: 395 - 397

12. Field methods of assessing winter hardiness in peas

    • B. D. Dowker

    OriginalPaper Pages: 398 - 402

13. Inheritance of amount of chlorophyll in wheat, Triticum aestivum L.

    • B. S. Ghai
    • A. K. Srivastava
    • K. S. Gill

    OriginalPaper Pages: 403 - 405

14. Spontaneous hybridization in wheat populations of Transcaucasia

    • V. F. Dorofeev

    OriginalPaper Pages: 406 - 416

15. Relation of seed weight to grain yields in oats, Avena sativa L.

    • K. J. Frey
    • T. F. Huang

    OriginalPaper Pages: 417 - 424

16. A simple effective embryo culture technique for brassica

    • D. J. Harberd

    OriginalPaper Pages: 425 - 429

17. Inter-specific hybrids of Lilium lankongense Franchet produced by embryo-culture

    • C. North
    • A. B. Wills

    OriginalPaper Pages: 430 - 434

18. Inheritance of leaf hairiness in Gossypium hirsutum L. cotton and its relationship with jassid resistance

    • S. Muttuthamby
    • M. Aslam
    • M. A. Khan

    OriginalPaper Pages: 435 - 439

19. Book announcements

    Announcement Pages: 440 - 441

20. News items

    Announcement Pages: 441 - 442