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Acroceras macrum Stapf is a palatable and nutritious tropical species which was popular as a pasture grass in South Africa approximately twenty five years ago. Its susceptibility to diseases and an apparent lack of seed setting ability were two serious detractions of an otherwise desirable species. A breeding programme was initiated at Cedara in 1970 and has, to some extent, overcome these deficiencies. Cytological and field investigations have revealed that tetraploid (2n= 36), pentaploid (2n= 45) and hexaploid (2n= 54) chromosome races occur and that the species is self sterile, but in certain combinations of strains of similar chromosome number and flowering date, highly cross fertile. Seed of A. macrum has a dormancy characteristic, germination improving after nine month storage. Several high yielding, disease resistant and otherwise desirable parental strains were selected for hybridization as single crosses and seed derived from these crosses has recently been planted in field experiments. UITTREKSELAcroceras macrum Stapf is 'n smaaklike en voedsame tropiese grasspesie wat ongeveer vyf-en-twintigjaar gelede 'n baie gewilde weidingsgewas in Suid-Afrika was. Die gras se vatbaarheid vir siektes en die klaarblyklike afwesigheid van saadset was egter twee ernstige tekortkomige van hierdie andersinds voortreflike gras, 'n Teelprogram is in 1970 te Cedara begin om tot 'n sekere mate hierdie tekortkomige te oorbrug. Sitologiese en veld ondersoeke het aangeton dat tetraploïede (2n=36), pentaplotede (2n=45) en hexaplofede (2n=54) chromosoon rasse voorkom en dat die spesie selfsteriel, maar in sekere kombinasies van lyne met dieselfde chromosoom aantal en waar blomdatums ooreenkom, hoogs kruisvrugbaar is. Saad van A. macrum het 'n rusperiode nodig en verhoogde ontkieming is gekry nadat saad vir nege maande geberg is. Verskeie hoog produserende, siekte bestande en andersinds voortreflike ouer lyne is geselekteer vir kruising as enkel kruise en saad verkry van hierdie kruisings is onlangs in veld proewe Mitgeplant.

A breeding program was conducted to improve the forage quality of Lolium multiflorum. Fifteen cultivars grown in spaced-plant trials were subjected to selection for a low moisture and a high non-structural carbohydrate content. Results showed consistent positive correlations between non-structural carbohydrate content, dry matter content, and digestibility in vitro of the grass. In a small plot trial comparing F6 plants (Selection 121) with 11 commercial L. multiflorum cultivars, Selection 121 gave the second-highest dry matter yield (difference not significant, P > 0.05) of the cultivars tested. The dry matter content of Selection 121 was significantly higher and the acid detergent fibre content significantly lower than that of the commercial cultivars. Furthermore, the total non-structural carbohydrate content was significantly higher and the nitrogen content significantly lower than that of the other L. multiflorum cultivars, giving Selection 121 nutritionally a much more favourable readily digestible energy to protein ratio than the commercial cultivars. Selection 121 was subsequently named 'NCD Enhancer' and is inscribed on the South African Variety List.