Arrowleaf clover (Trifolium vesiculosum L.) is a late maturing annual legume which has the potential to be used in a range of farming systems such as finishing lambs through to silage production and building soil fertility for future cropping. An experiment at Lincoln University, Canterbury, evaluated the performance of 'Arrotas' arrowleaf clover relative to white and subterranean clover from 23 May to 20 December 2007. By the 20/12/2007, 'Arrotas' produced 9800 kg DM/ha compared (P<0.001) with 3370 kg DM/ha from subterranean and 1790 kg DM/ha from white clover. Metabolisable energy in late December was similar for all clovers. Results in Australia at similar latitudes and rainfall regimes to parts of the North and South Island of New Zealand suggest that 'Arrotas' could be successfully incorporated into local dryland systems.

Germination of 'Cefalu' arrowleaf, 'Bolta' balansa, 'Prima' gland and 'Mihi' Persian clovers was determined from constant temperature (5-40°C) from incubator experiments. A 'broken stick' regression of germination rates against temperature was used to quantify thermal time (Tt) requirements and cardinal (base, optimum and maximum) temperatures. Tt requirements for 75% germination were higher for 'Cefalu' arrowleaf (34°Cd) than 'Bolta' balansa (32°Cd), 'Prima' gland (28°Cd) and 'Mihi' Persian (25°Cd) clovers. All species had a base temperature of 0°C. 'Mihi' Persian clover had an optimum temperature (T opt ) of 33°C and a maximum temperature (T max ) of 45°C, while all the other species had T opt between 16-20°C and T max of c. 34°C. The maximum final germination percentage was above 60% for 'Cefalu' arrowleaf clover and 80% for the other three species.

The development process from floral bud formation to seed maturity of four top flowering annual clovers was quantified from a field experiment across 10 sowing dates at Lincoln University, Canterbury, New Zealand. For each species, a numeric reproductive scale was created as a field guide to document morphological changes as the bud progresses through reproductive development. The duration from bud visible to open flower was 341 °C days for 'Cefalu' arrowleaf, 215 °C days for 'Bolta' balansa, 196 °C days for 'Prima' gland and 186 °C days for 'Mihi' Persian clover. The inflorescence then required a further 274-689 °C days, 185 °C days , 256 °C days and 425 °C days for each respective species to reach physiological maturity. This was indicated when 50% of seeds had turned red/brown for 'Cefalu' arrowleaf, 100% pods turned yellow for 'Bolta' balansa, 100% of seeds were yellow and hard for 'Prima' gland, and pods turned brown with the first sign of colour change in seeds for 'Mihi' Persian clover. These results can be used to facilitate on farm decision making in relation to grazing management or seed set for subsequent regeneration. Keywords: floral development chart, harvest maturity, peak flowering, pollination, seed filling, thermal time, Trifolium vesiculosum, T. michelianum, T. glanduliferum, T. resupinatum

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Monocultures of arrowleaf (Trifolium vesiculosum), balansa (T. michelianum), gland (T. glanduliferum) and Persian (T. resupinatum) clovers were sown on four dates in autumn and winter 2010. Dry matter (DM) accumulation was dependent on the duration of crop growth which was influenced by the time of sowing. Autumn sown crops which flowered latest had a longer duration of vegetative growth and consequently produced the highest dry matter yields. In the establishment year, autumn sown crops produced up to 17.5 t DM/ha for balansa, 12.5 t DM/ha for Persian, 11.0 t DM/ha for gland and 9.4 t DM/ha for arrowleaf at physiological maturity (P

This study was conducted to compare the agronomic performance of four elite cocoa clones (MCBC1, KKM22, KKM4 and PBC230) regenerated from staminode and immature zygotic embryo culture with conventional grafted cocoa clones. From the results, it was found that the KKM4 clone propagated from immature zygotic embryo culture exhibited variations in the fresh pod weight (339.6 g), fresh individual seed weight (4.13 g) and number of flat beans per pod (4 beans) compared with the rest of the regenerated clones. The genetic stability of the somatic embryogenesis cultured clones and the donor clones was then tested using fragment analysis with five SSR primers, i.e. mTcCIR7, mTcCIR18, mTcCIR22, mTcCIR33 and mTcCIR40. Four of these primers identified variations in the allele size and allele addition in KKM4 clone from immature zygotic embryo. Molecular analysis validated that the difference in agronomic performance of the KKM4 clone from immature zygotic embryo culture was due to genetic mutation created during the immature zygotic embryo culture process.

a b s t r a c tLeaf appearance rate and time to canopy expansion of four annual clover species (arrowleaf, balansa, gland and Persian) were quantified in field and controlled environment studies. Crops sown in autumn, which experienced shortening daylengths at emergence, had a slower rate of leaf production and consequently took a longer time to initiate branching, than spring-sown crops. When autumn-sown 'Bolta' balansa clover emerged on the shortest day in winter (21 June), the rate of leaf appearance was lengthened by 4 • C d/leaf/h. When the same species emerged after the shortest day, into an increasing photoperiod, the phyllochron was shortened by 5 • C d/leaf/h. This influence of photoperiod on the phyllochron consequently altered the time to axillary leaf production (branching). Throughout all sowing dates, phyllochron was the fastest for 'Prima' gland (33-91 • C d/leaf) and slowest for 'Cefalu' arrowleaf (53-116 • C d/leaf) clovers. 'Bolta' balansa was 44-82 • C d/leaf and 'Mihi' Persian 61-93 • C d/leaf. The response of phyllochron to photoperiod suggests these annual clovers should be sown in late summer or early autumn to initiate axillary leaf production as soon as possible to ensure maximize dry matter for early spring.