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A comparison was made of establishment of five white clover lines sown as pure swards on soil infested with stem eelworm tDitylenchus dipsaci) and on uninfested soil.On infested soil two lines found to be resistant (Morocco X 'Grasslands 4700' and Ladino X 'Grasslands 4700') showed most rapid establishment and least production loss due to poor establishment. A very susceptible line from Israel suffered severe loss due to eelworm attack, and the varieties 'Grasslands Huia' and 'Grasslands 4700', known to be of intermediate susceptibility, showed an intermediate loss of production due to the effects of eelworm on establishment.All except the Israeli line recovered from the initial effect of eel worm attack on newly germinated seedlings and within 9 months from sowing were producing as much forage dry matter in the presence as in the absence of eel worm.Recovery was possible by virtue of the sprawling nature of the white dover plant, the rate being related to the proportion of seedlings which survived eelworm attack. This recovery phenomenon may explain the absence of apparent economic eelworm effects in established New Zealand pastures.

SUMMARYB-chromosomes ranging in number from one to 12 had a deleterious effect on the vigour and fertility of a population of tetraploid hybrids between:(Natural 4x) Dactylis glomerata ssp. glomera/a and (Induced 4x) Dactylis glomera/a ssp. lusitanicll. Similar trends in vigour and seed set were shown by the original diploid D. glomerata ssp. lusitanica lines, but pollen fertility appeared to be enhanced by low numbers of B-chromosomes.With increasing B-chromosome number induced tetraploid D. glomerata ssp. lusitanicll showed a reduction in the total seed set within each cross.

A brief outline is given of the breed'ing of the new clover 'Grasslands 4700'. Reports are made on the performance of 4700 as single plants at Kaikohe, Palmerston North: Lincoln and Gore, and -as motin swards with associated grasses at Palmerston North. ln all trials, 4700 was superior to Hum in wmter, and equal to or better than Huia in the summer, except at Lincoln where it was inferior. Based on these results seed was released for widespread trials in order to assess its regional adaptation and its performance in mixed swards under different systems of management.

Eighty-seven lines of cocksfoot were examined as spaced plants at Palmerston North.

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WESTERN WOLTHS, the extreme annual form of Italian ryegrass (Lolium multiflorum Lam.), is a fodder grass which orginated in the Netherlands (De Haan, 1955). Thirty to forty years ago it was widely used in Canterbury but its use died out with the advent of the certification scheme and the availability of good perennial ryegrass-white clover pastures. Saxby (1956) states that the questionable value of Western Wolths ryegrass has not warranted its inclusion in the certification scheme, and that in 1956 genuine seed was practically non-existent on the New Zealand market.