Morphology, flowering, cyanogenesis and leaf markings of 109 white clover (Trifolium repens L .) cultivars, grown as spaced plants and in small plots, were measured . Principal component analysis and cluster analysis were used to compare cultivars . Cultivars were classified into four broad groups . The most important criteria for distinguishing between groups were leaf size, cyanogenesis and combinations of these . Group I, termed small, included small-leaved, prostrate cultivars ; Group II, termed intermediate, included the majority of the cultivars which were characterised by medium sized leaves and relatively low cyanogenesis levels ; Group III, termed large, included the large-leaved highly cyanogenic cultivars ; and Group IV, termed ladino, included large-leaved acyanogenic cultivars .

A New Zealand-wide postal survey of farmers was undertaken in the winter months of 1985 seekinginformation on farmerknowledge and use of pasture cultivars commercially availablein New Zealand, their sources and adequacy of information on these cultivars, pasture problems, and amount of pasturerenewal carried out. Of the 1700 questionnaires sent out, 943 (55.5%) valid returnswerereceived. Perennial ryegrassand white clovercultivarshad the highestlevelof knowledge and use. Farmerstended to have better knowledge and higheruse of oldercultivars, withonly thenew perennial ryegrass cultivars 'Grasslands Nui' and Ellett among all farmers and 'Grasslands Pitau' among dairy farmers being higher than older cultivars. New cultivarsof other grass and legume species werelessusedthanoldercultivars.lnregions wheremajorresearchwas carriedout on a specific cultivar, its level of use by farmers in the region appearsto have been influenced Farmersrevealed stronguseofagriculturaljournals (e.g.,Proceedings A89043 of the New Zealand Grassland Association), their district farming paper, and the daily newspaper's farming page for seeking information on new cultivars,andgrainandseedmerchantrepresentatives werethe mostpopularpersonalsourcesof information.Though60%of the farmers indicatedsatisfaction with information received on seed mixtures, 76%consideredthatdistrictpaddock-sizedemonstrationareasofnewcultivarswouldbethemostappropriatewayofpromoting thenewcultivars. 62%of the samplelisted pasture problems they wished to see researched for theirdistrict.

-]-hi. raiiKi. (if lariaiion fur pliviiLiypic plasiiiiiy for mcirphnloBical and yield relaiod tharacitrs. taiisid by varyi.ic llu. k-vcl t»l' pluwphiJTVis 0') s\ipply. \v;i^ tk.\L.rmiiu.il both across and wiiliin i..nlli\ars uf ulntv clovt.r [Tnh'tuim irltrm [..]. ..Vi.aly.^is uf variauci. «as ustd as a ciiialitaiivt niuasure uf plu-nutypic pla.^iiiciiy (i.e. sieniHcanfi. uf P MrO) and lu dcirrniini. diUVrmtial plicnutypic plasiitiiy (i.e. sienilicante of cenutypc x P intcraciiun). Qnadratic 1' response eurves iveie ealeulaied and plasiieiiy measured quan(itively as maxiniuTii slope.WliiU. .\\\ pV.mv i:lv.ir;u\evs measineti esliihiled plv\snchy. yiekl rel..Uetl tiv.n'aaers were Kcnetally more plasiic liiiin eharaercr.s assoeiaied witli plain inorpliuloi,.\-when euiripared usiny a seale independent le.s( based un l'^-raiius. Internode lenjjih and lecif size ivere ihe mos( piasiie morpholouieal draracrers and i( is suRBested rhai ihey are ehielly responsible for tbe resnltan( yield response ol \vhi(e elover to tnereased pliospbate fertdtser supply. 1 here was hij;hK-aiBnilicvmi v..«u«iim (or plasi.ciiy .mmns cinotypes (\>y all pV.im eharatltrs measureci. ..Jllimigh vvithin enltivars. siKttilieanee of lariat.on for plastieity attx.nB Ben.>iypes varied »ith eiiltivar. Magnitude of plastieity of gfnon'pL' w;js IHK CI^JSOK-t-uhiteil \u 'irigiii nt' culli^'iir-. pUint [\'PL', i^rov^'th or brcutiing history. ^I:iny cfiin"ictt*Mstic.*i varied independently for plastieity -fbe large variation (.b^erved for phenu(ype plasrieity wuuld sugBest tltat Iweedi.iE for ati ««re.,se .>r decrease in plaaichy uf ebaraoers is an ..ehk.v.iWe uptiu,,.Keywutds: Morpbulogy. pbettoiypie plast.eiiy. pltusphurus. TnfoHiuii rrfr,,, (>vltiie eluver). yield.

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