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Ryegrass, both perennial (Lolium perenne) and annual (L. multiflorum), can be weeds in other arable crops such as wheat (Triticum aestivum). They are generally removed using selective herbicides, but herbicide-resistant perennial and annual ryegrasses have been reported anecdotally. Perennial ryegrass seeds that were suspected to be herbicide resistant were sourced from near Methven, Canterbury. They were evaluated for tolerance to five herbicides and were found to be resistant to all of them. In a separate experiment, annual ryegrass seeds that were suspected to be herbicide resistant were also sourced from near Methven, Canterbury. They were evaluated for tolerance to six different herbicides and were found to be resistant to haloxyfop applied at up to four times label rate but susceptible to clethodim. These results have important implications for growers and advisers throughout New Zealand.

New Zealand hill and high country are marginal environments for perennial ryegrass and white clover. Other pasture species, particularly legumes, provide more productive and persistent options for the range of soil climate and topography found in these environments. On cultivatable hill country, lucerne (alfalfa) has been successfully introduced to dryland areas with imported seed increasing five-fold to 210 t per annum over the last decade. This has led to the first release of a New Zealand selected cultivar in 20 years. For subterranean clover reliance on hardseeded Australian cultivars that frequently fail to meet New Zealand biosecurity standards means seed supply is inconsistent. The potential exists to create a niche seed market through selection of locally adapted material grown for seed in New Zealand. Lotus pedunculatus is available commercially but seed often fails to meet certification standards and is predominantly used in forestry. Lotus corniculatus requires agronomic research to overcome some management constraints and the re-establishment of seed supply before it would be a viable option for drier hill country. Seed production for perennial lupins in New Zealand is predominantly for an export ornamental market, with some direct relationships with growers allowing onfarm use. Caucasian clover seed production has ceased in New Zealand and the demand for seed particularly from high country farmers is no longer met. The smallseeded annual balansa clover is being integrated into farm systems and its prolific seeding has enabled some on-farm production of seed for personal use. For it and arrowleaf and Persian clovers, imported cultivars are available and a local market is unlikely to thrive until agronomic and hard seed issues are addressed. Seed supply of forage legumes to satisfy demand for hill country is problematic and will require development of different models including grower co-ops, regional seed retailers, and on-farm production for niche markets. Keywords: alfalfa, Lolium perenne, Lupinus polyphyllus, Medicago sativa, perennial ryegrass, Sitona lepidus, Trifolium ambiguum, Trifolium michelianum, Trifolium repens, Trifolium resupinatum, Trifolium subterraneum, Trifolium tumens, Trifolium vesiculosum, white clover

A summary of seed yield data from 19 fungicide trials in perennial and hybrid ryegrass (Lolium spp) seed crops conducted over a 12 year period is presented Seed yields from the best fungicide treatments were increased on average by 25 in forage ryegrass (390 kg/ha) and 42 in turf ryegrass (580 kg/ha) Seed yield increases were associated with the control of stem rust and/or maintaining green leaf area during seed fill In turf ryegrass (susceptible to stem rust) delaying the first fungicide application until stem rust appeared resulted in seed yields that were not different (P>005) from the untreated experimental controls whereas early fungicide applications from the beginning of reproductive development increased seed yield by between 36 and 42 Fungicide mixes of a triazole plus a strobilurin usually gave higher seed yields than using either fungicide type alone

Forage grass seed yields are often low and variable with only 10–20% of the above ground matter harvested as seed. Seed yield is affected by the amount of carbohydrate transported to the seed. However, information regarding the storage and mobilisation of carbohydrates during reproductive development in forage grasses is limited and the contribution of stored and current assimilate to seed yield from vegetative tissues is equivocal. To identify whether the total amount of carbohydrate in the plant might be limiting seed yield, and the contribution of vegetative and reproductive tissues to seed yield, the pattern of accumulation of water-soluble carbohydrates (WSC) and their remobilisation was investigated in field-grown perennial ryegrass ( Lolium perenne L.) plants. Tillers were sampled from early head emergence through to harvest. Amounts of WSC in leaf blades, leaf sheaths, internodes and reproductive heads of the tillers were measured in two ways. Firstly, WSC were estimated indirectly by changes in tissue dry weight. These changes were then used to determine any apparent translocation of WSC from vegetative tissues to the developing seed. Secondly, WSC concentration was measured directly. Low molecular weight (LMW) and high molecular-weight (HMW) WSC were extracted from vegetative and reproductive tissues and the concentrations quantified using a colorimetric anthrone assay. The seed yield of the crop was high (2950 kg h −1 ) and the dry weights and the amount of LMW and HMW WSC in vegetative and reproductive tissues changed significantly during reproductive development. High concentrations of HMW WSC were found in the internodes post head emergence and these concentrations continued to increase during seed fill through to harvest. Total dry weight of the internodes also increased over the same period. In contrast, in the leaf blades and leaf sheaths, total dry weight decreased only slightly while the initial low concentrations of WSC steadily declined. In the heads, WSC increased significantly during seed fill and subsequently declined while the dry weight continued to increase through to harvest. The ratio of LMW and HMW WSC also changed during development depending on the tissue type and growth stage. The present study indicates that the seed head itself maybe an important factor driving seed fill. Knowledge of the mechanisms that underlie carbohydrate partitioning to the seed could in future result in significantly higher yields.

The viability of the New Zealand herbage seed industry is influenced by national and international factors and changes in consumer requirements. Four main species perennial ryegrass (Lolium perenne), Italian ryegrass (Lolium multiflorum), tall fesuce (Festuca arundinacea) and white clover (Trifolium repens), account for more than 98% of the herbage seed grown in New Zealand. Annual production averages 22000 t, of which 70 to 80% is grass seed with perennial ryegrass (L. perenne) being the largest component. There have also been significant production changes among species with Italian ryegrass (L. multiflorium) in particular increasing in importance, with production doubling between 1999 and 2003. There has been a marked reduction in total area for herbage seed production over the past decade, however, this has been offset, particularly in ryegrass, by higher seed yields per ha. These improvements in seed yield have primarily been achieved through implementation of better management techniques. The increased use of the plant growth regulator trinexapac-ethyl has been very beneficial in grass seed production. There has also been a major shift in New Zealand seed production towards the production of proprietary cultivars. In white clover, for example, proprietary cultivars represented less than 10% of production in 1991 but have increased to 57% in 2003. The rapid uptake of the novel AR1 endophyte technology in proprietary ryegrass cultivars, which has grown from 0% in 2000 to 21% of perennial and hybrid proprietary ryegrass seed produced in 2003, is an excellent example of what can be achieved with an addedvalue product. The future viability of the New Zealand herbage seed industry requires further development of identifiable added value traits associated with the seed. Keywords: AR1 endophyte, plant growth regulators, production statistics, ryegrass, seed production, tall fescue, white clover

The nutritional benefits of condensed tannin (CT) in forages such as Lotus are known but difficulties with establishment, herbage production and persistence in a pasture have hindered farmer uptake of this valuable legume. A sheep grazing experiment was established to investigate the effects of growing three Lotus corniculatus (Grasslands Goldie, G46 and Creeping) and two L. pedunculatus (Grasslands Maku and Grasslands Trojan) cultivars with or without Grasslands Advance tall fescue (Schedonorus phoenix syn. Festuca arundinacea) and with or without white clover (Trifolium repens) under infrequent (8-weekly) grazing. Without grass, the content of L. corniculatus and L. pedunculatus in the swards was 85% and 60% respectively by year 3. Adding white clover reduced the Lotus content in the swards by 20%. With tall fescue, the L. corniculatus cultivars increased from 6 to 34% between the summer of year 2 and year 3. In contrast, the L. pedunculatus cultivars remained at very low 1- 2% levels in the summer of both years. Inclusion of white clover did not further reduce Lotus content in the tall fescue swards. While there was no significant difference in content and yield between L. corniculatus cultivars, there was a consistent trend for Goldie to produce more herbage. Goldie had the potential to produce 2 t dry matter (DM)/ ha/year in a mixed pasture with tall fescue under infrequent grazing. Creeping L. corniculatus contained higher CT levels than Goldie (3.5 cf.1.1% of herbage DM respectively) and is thus potentially able to provide greater amounts of CT in a pasture. Trojan and Maku L. pedunculatus had similar plant density and herbage productivity. The experiment will be monitored further to determine the long-term persistence of these Lotus cultivars in a mixed pasture. Keywords: condensed tannins, infrequent grazing, legume composition, Lotus corniculatus, L. pedunculatus, tall fescue, white clover

Seed yields of ryegrass and tall fescue have increased rapidly over the last seven years; the best farm yields are now reaching 3000 kg/ha, up from 2000 kg/ha. These increases are largely due to the adoption of technologies developed from research funded from grower crop levies and effective technology transfer programmes. The key technologies are (1) the adoption of trinexapac ethyl (TE), a plant growth regulator that blocks gibberellic acid biosynthesis and reduces lodging; and (2) new generation triazole and strobilurin fungicides that give improved disease control and extend the period that green leaf area is maintained on crops. Seed yield data from 10 ryegrass and 6 tall fescue trials with TE, and from 13 fungicide trials are presented. The average seed yield increase in tall fescue treated with 200 g TE/ha and ryegrass with 400 g TE/ha was 67% and 50% respectively. In fungicide trials, seed yields in forage perennial ryegrass were increased by 20% and in turf ryegrass by 42%. A survey of growers indicated 95% of ryegrass growers and 100% of tall fescue growers had adopted the use of TE three years after the commercial release of the product. Keywords: fungicides, plant growth regulators, ryegrass, seed yield, strobilurin, tall fescue, triazole, trinexapac

Canada geese (Branta canadensis) and other herbivorous birds (e.g. paradise ducks, pukeko) can be a significant problem for both pastoral farmers and recreational turf managers in a number of locations in New Zealand. Canada geese were offered seeds and herbage of selected ryegrass combinations of (Lolium perenne) and endophyte (Neotyphodium lolii) to examine the effects of endophyte and the associated alkaloids on feeding behaviour. Forty geese were captured annually during the moult in January and contained in fenced areas by wing clipping. In both choice and no-choice feeding trials, geese consumed up to four times more endophyte-free than endophyteinfected ryegrass herbage. In a seed feeding trial, the geese did not discriminate on first exposure between the endophyte-free seed and that containing endophyte. However on Day 2 there was an 80% rejection of the seed containing endophyte compared to the endophyte-fr ee seed. A similar rejection of 80% was observed after a three month endophyte-free feeding period, suggesting the rejection was a long term learned response involving post-digestion feedback. Grass/endophyte associations may add to the armoury of bird control methodology as a tool to manage birds using habitat modification. Keywords: alkaloids, Canada geese, endophyte, herbage, post-digestion seed

Fenoxaprop P-ethyl, a wild oat herbicide was applied to five grass species. Perennial ryegrass was tolerant to 37 g/ha, but there was a trend for a reduction in seed yield at 75 g/ha. Two Bromus species had good tolerance, but Phalaris aquatica seed yields were reduced by 80%. In a second trial, there was no significant effect on seed yield of perennial and hybrid ryegrass to fenoxaprop applied at 56 g/ha. However, there was a trend for 75 g/ha to reduce seed yield in perennial ryegrass. In a perennial ryegrass seed crop, wild oats were very competitive, reducing seed yields from 2600 kg/ha (best herbicide treatment) to 660 kg/ha in the untreated control. Excellent wild oat control was achieved with fenoxaprop at rates of 45 g/ha in August and 56 g/ha in September.

Experiments in grass seed crops investigated the control of volunteers in phalaris (Phalaris aquatica) and tolerance of phalaris seed crops to four herbicides and tall fescue (Festuca arundiacea) to eight herbicides. Atrazine at 2040 g/ha gave 94% control of volunteer phalaris and both atrazine at 2040 g/ha and ethofumesate at 2000 g/ha showed good tolerance with phalaris seed yields of 760 and 750 kg/ha compared to untreated control which had a seed yield of 620 kg/ha. Tall fescue seed yields showed good tolerance to terbuthylazine at 750 g/ha, prodiamine at 65 g/ha, chlorpropham at 1200 g/ha, diuron at 1800 g/ha and oxyflurofen at 288 g/ha with seed yields of 2580-2730 kg/ha compared to untreated of 2200 kg/ha. In the second year, burn treatments with metolachlor at 1920 g/ha gave 88 % volunteer control with a seed yield of 1380 kg/ha compared with untreated control of 1090 kg/ha.

Emergence of volunteer perennial ryegrass (Lolium perenne L.) from seed buried in soil may contribute to the ingress of ryegrass in newly sown pastures. To investigate this, ryegrass seed infected with fungal endophyte (Neotyphodium lolii) was buried in nylon bags under pasture at two depths and at two sites (Palmerston North, Lincoln) in early/mid-autumn 1998. Seed bags were removed from the soil at intervals over the course of one year to determine seed viability and presence of endophyte in seedlings. Viability of seed declined rapidly to be 10% 3 months after burial. Further decline in viability was less, so that 12 months after burial 4% of seeds were still viable. Endophyte viability also declined, from 58% infection of seedlings at the time of burial to 21% at 12 months. This was at a slower rate than the decline in seed viability and from what might have been predicted from seed storage experiments. Viability of seed buried at 10 cm was greater than that buried at 3 cm (e.g., means, 10% and 1% after 6 months, respectively). This has implications for cultivation practices before pasture establishment. Seed buried at Lincoln maintained higher viability than seed buried at Palmerston North (e.g., means, 6% and 4% after 6 months, respectively), which was associated with drier soil conditions at Lincoln. Survival of buried seed may therefore be of greater importance in summer-dry east coast regions, compared with moist west coast environments or in wet years. The significance of buried ryegrass seed will depend on the numbers involved, but after 12 months there were still viable seeds left in the soil and some of these were infected with endophyte. This is important for pastures sown with ryegrass that is free of endophyte or infected with a selected endophyte, and for slower establishing grass species such as tall fescue. Keywords: endophyte, endophyte survival, Lolium perenne, Neotyphodium lolii, perennial ryegrass, seed burial, seed survival

Seed Certification and Seed Testing Schemes provide the rules and guidelines to maintain both varietal genetic purity and physical purity during field production and seed processing. However the Seed Certification agencies are not involved in ensuring that the quality of the endophytic component of seed is maintained. The delivery of quality endophytic seed to end users therefore requires that the commercial seed entity that is producing and marketing a novel endophyte product develops and maintains strict production and quality assurance guidelines to ensure that the benefits of novel endophyte technology are realised. The paper uses the New Zealand (NZ) experience with AR1 endophyte in ryegrass and the USA experience with MaxQ® Jesup tall fescue to highlight the quality control steps required to deliver a quality product to end users. Keywords: novel endophyte, tall fescue, ryegrass, Neotyphodium, MaxQ, AR1, seed production

In a browntop (Agrostsis capillirs syn. A. tenuis) crop, weeds reduced seed yields by up to 78% (485 kg/ha). When the weed mass contributed 10 to 50% of the dry matter, every 1% increase in weeds decreased seed yield by 9.4 kg/ha. The main weed species causing yield loss were broadleaved species. The two best herbicide treatments were a mixture of metsulfuron 3 g/ha + mecoprop-bromoxynil-ioxynil 1035225-225 g/ha; and a mixture of metsulfuron 3 g/ha + triclopyr 180 g/ha. In a first year browntop crop seed yields were tolerant to metsulfuron 3 g/ha, tribenuron 22 g/ha, thifensulfuron 30 g/ha, and diflufenican + bromoxynil 75 + 750 g/ha.

Control of Rumex species in phalaris (Phalaris aquatica L.) by four herbicides and tolerance of phalaris seed crops to a range of herbicides was investigated in two trials. Dicamba at 400 g/ha gave 100% control of Rumex species in both years (0 and 1 Rumex seed/40g phalaris seed). Thifensulfuron at 15 g/ha gave 100% and 99.7 control (0 and 15 seeds/ 40g). These treatments were more effective than asulam or a 2,4-D + dicamba mixture. Phalaris seed yields had good tolerance to mecoprop and dichlorprop mixtures, tribenuron-methyl, TCA + 2,2-DPA, prodiamine, and diflufenican + bromoxynil. Fenoxyprop-P-ethyl is not recommended for phalaris seed crops.

Perennial ryegrass seed has been one of the most profitable large scale arable crops in the long term, where good yields have been maintained. The key factor in producing high yields of quality ryegrass seed is to take a 'specialist crop' approach. By following the principles given here, specialist growers are achieving consistent seed yields of 1500 kg ha".

Fungal endophyte (Acremonium spp.) toxicity affects sheep and cattle grazing a number of forages, including ryegrasses (Lolium spp.) and tall fescue (Festuca nrundinacea). The endophyte in tall fescue is responsible for ill thrift, as indicated by low weight gains or weight loss(1) and decreased reproductive efficiency(2), and is associated with increased body temperatures. Extensive research has been undertaken in the USA to determine ways of reducing the impact of fescue toxicity on the beef industry(3), whilst New Zealand research is directed toward both ryegrass and fescue endophyte toxicity and its impact on sheep(4)(5) and cattle(6) production. Much of this work involves field evaluations of productive performance in animals fed toxic and non-toxic forage, so that it is important to be sure that treatment effects are due to the endophyte.

Hill country pasture was sprayed with low fates of the herbicides paraquat, sethoxydim or Dowco 453 in late November. Legume content of the pasture 6 weeks after application increased from 29 to 61%, and from 12 to 31% in January 1983 and 1984 respectively. The chemicals reduced dry matter yields by 16 and 45%, 6 weeks after treatment, but yields were not reduced in subsequent harvests. The chemicals reduced dead matter content, strongly suppressed grass seed head production, increased clover seed head density and increased in vitro digestibility. Sethoxydim at high rates 150 g/ha reduced perennial ryegrass (Lo/km perenne) content, but Dowco 453 increased perennial ryegrass and decreased browntop (Agrosfis tenuis) content. The effect of clover content and dead matter on sheep diet selection is shown and the implications of these results for management of hill country pastures in moist si;m.mers are discussed. Keywords: herbicide, paraquat, sethoxydim, Dowco 453, white clover, Trifolium repens, hill country, in vitro digestibility, perennial ryegrass, Lolium perenne ryegrass, Lolium perenne browntop, Agrostis tenuis.

Buried hard seed from seed returned to the soil during harvesting and incorporated by cultivation, poses the greatest threat of contamination. When a different white clover (Trifolium repens L.) is sown, contamination will occur when hard seeds within the germinating zone soften and emerge. Harvest losses can return 40 to 210 kg/ha of hard seeds to the soil. Flowering management and efficient harvesting are necessary to minimise quantities of hard seed returned to the soil. For a buried seed load of 845/m* in the germinating zone of a cultivated seed bed at sowing in March, 8% of that seed load gave rise to establishing plants of which one-third (19/m') were surviving in mid-October. At closing the percentage crop contamination within the sown row was directly proportional to the within-row seeding rate of the sown cultivar. At wider-than-normal row spaces, (45 cm compared with 15 cm) either inter-row cultivation or spraying for removal of contaminants was necessary at closing to reduce contaminants to a density similar to that in 15 cm spacing treatments. Physical contamination of the harvested seedline, compared with levels present at closing, had doubled for normal, but trebled for wider-than-normal spacings. Lowest percentage physical contamination of a seedline gained was 13% for a 6 kg/ha seeding at 15 cm spacings. The results indicate that successful cultivar change on many areas will be difficult. A buried seed count is considered an essential guideline to aid choice of paddock. Future management systems now being developed, include the use of herbicides and direct drilling, and should help to minimise this problem. Keywords: White clover, Trifolium repens, seed production, contamination, cultivar change, harvest losses, hard seed, cultural practices.

The effect of storage on viability of the Lolium endophyte fungus (Acremonium loliae Latch, Christensen and Samuels) in seed of perennial ryegrass was studied. Treatments included four initial seed moistures (13.8, 12.1, 10.0, and 8.6%); different storage bags (calico, polyethylene film (9, 35, or 70 μm thickness), and laminated aluminium foil-polyethylene); and four storage conditions (ambient 5–25°C, 5°C/70% RH; 0°C/30% RH; -15°C/90% RH). After 12 months of ambient temperature storage, seeds with final moisture contents > 11.3% had a rapid linear decline in endophyte viability from an initial 84% to < 15% at 13.0% seed moisture. Samples in 70 μm thick polyethylene and aluminium foil laminated packets had the highest endophyte viability (70–78%) at ambient temperatures. Seed stored at 5, 0, or -15°C had high endophyte viability with no effect of seed moisture. Seed germination was not affected by any treatments. Cool or low humidity environments ( < 60% RH) are required to maintain viability of ...