1. From. the field. 2. CROPS 2012 your help? Crop type. Districtt. Sow date April August. sown wheat. Autumn. April. emerging) ryegrass.

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1 Friday, November 30, 2012 This edition includes: 1. From the Field 2. CROPS Septoria tritici samples needed a reminder for the need for your help? 1. From the field Growth Stages for a range of crops and regions. Crop type sown wheat Spring barley Districtt Manawatu Manawatu Sow date August Growth stage GS61 (early flowering) GS49 (awns emerging) Mid season perennial ryegrass Late season perennial ryegrass sown wheat sown barley Spring wheat Spring barley White clover Forage rape seed GS32 (second node) first heads emerging GS30/31 (ear at 1 cm) GS50 59 (ear emergence) GS70 79 (milk development) GS39 GS51 (flag leaf to ear emerging) GS32 GS49 (second node to awns emerging) first flowers appearing/topping occurring End of flowering sown wheat sown barley sown barley Southland Southland Southland May GS45 (mid boot) GS70 (Early grain fill) GS65 (mid flowering) Southern North Island: Althoughh autumn drilled crops are looking good at the moment, the very dry conditions in the Manawatu and Hawkes Bay are a concern. Conditions are not conducive for disease development at the moment; however there is scald in the base of barley canopies and rain forecast for the end of the week. Growers are considering options for ear wash sprays on autumn drilled wheat (see disease management strategy in next section). The dry conditions mean that pre emergent residual herbicides may not have activated in spring barley crops. Monitor grass weeds in these crops. Mid : Stripe rust is present in susceptible cultivars where the gap between fungicide applications has been left too long. Stripe rust has been observed developing in Einstein and Raffles which are approaching ear emergence in the Methven area, while Septoria continues to tick away in the base of many crops. Stripe rust and leaf rust are developing on susceptible cultivars in the CPT trial at the FAR Chertsey Arable Site where one replicate is not being sprayed with fungicide. 1

2 In ryegrass, no stem rust lesions have been found to date. Crown rust is on some older leaves of susceptible cultivars. There is very light frost damage in some kale brassica seed crops. South : Generally disease in wheat crops is well controlled. Take all is showing up in some second year wheat crops. Scald is present in barley crops particularly where spray intervals have been stretched. Ramulariaa leaf and awn spot has been observed in autumn sown barley crops. This disease can reduce green leaf area very quickly but is well controlled by a good spray programme (see Cropping Strategies: Cereal disease management for fungicide options). Nui is approaching full head emergence and plant growth regulator is now going on later cultivars. Aphids are infesting oilseed rape and brassica seed crops. If control is necessary be vigilant with bee safety when applying insecticides to flowering crops. Southland: Frost damage in some autumn drilled barley paddocks appears to be as much as 50%. Scald has not been that well controlled in barley crops where the gap between sprays has been too long. Septoria is present in the base of wheat crops. Written by: Rob Craigie and Richard Chynoweth. Acknowledgements: Tom Sherratt, Murray Kelly, Mark Evans, Phil Prendergast, Mark Currie, Tim Naylor, PGG Wrightson; Matthew Cromey, Plant and Food Research. drilled wheat diseasee management With crops approaching flowering it is time to consider disease management for this important growth stage. Many dryland crops are well setup with soil moisture to date, so consider a fungicide programme similar to that for irrigated crops. The following disease management strategy for ear emergence to early grain fill was developed based on recent FAR trials. GS59 61 (ear emergence start of flowering) In irrigated scenarioss Recent FAR research has suggested there are benefits to be gained from higher fungicide rates where better protection against leaf rust is required at this timing. Therefore, where cultivars are susceptible to leaf rust, a good standard would be Opus 0.5 l/ha + Comet 0.4 l/ha, which is particularly effective against leaf rust when applied at ear emergence (GS59). This should also be particularly effective against Septoria tritici whichh has been at higher levels this season. This has been slightly more effective than other mixtures at this timing, however Opus l/ha + Amistar l/ha is still very effective and allows a later window of application up until the end of flowering (GS69). Also consider Seguris Flexi 0.3 l/ha mixed with Opus 0.5 l/ha at ear emergence (GS59) where two strobilurins have already been used earlier in the season and leaf rust is the target disease. 2

3 Where Septoria and particularly Fusarium sp head infection are the key target diseases then consider Proline (and mixed with tebuconazole e.g. Folicur for Fusarium sp) as a key ingredient for the ear wash spray. The timing for targeting Fusarium is critical (early flowering) and at best, disease control on the head is not likely to match thatt achieved for foliar diseases on the leaves. However, be aware that Proline is not as effective as Opus if leaf rust is also present. In dryland scenarioss consider the ear wash spray as an optional spray based on rainfall from flag leaf up until the end of flowering GS69 (anthers visible up the length of the ear). Consider applying fungicide should higher rainfall occur in this period, but don t overspend. Consider either Opus alone ( l/ha) or low rate mixtures such as Amistar ( 0.25 l/ha) + Opus (0.25 l/ha) which have been particularly effective. GS69 72 (Post flowering fungicide applications T4 s) Irrigated crops only optional For irrigated leaf rust susceptible wheat crops, on soils with good water holding capacity, there have been small advantages to applying an extra fungicide later than the ear emergence timing (usually two weeks after). However, work to date also shows that ncreasing the rates of fungicide applied at ear emergence (depending on product) can have the same effect. When considering late fungicides growers need to be extremely mindful of withholding periods. Mixtures based on Opus 0.25 l/ha + Amistar 0.25 l/ha (which have withholding periods of 42 and 35 days respectively) have delivered small but consistent yield benefits when applied following a similar application at ear emergence, but results weree no better than increased rates of Comet/Opus applied at ear emergence. Please note, in order to avoid applying more than two strobilurins (and to adheree to the anti resistance guidelines) in the crop using this approach would require omitting strobilurin from the flag leaf emergence spray. Notes: Above rates assume optimum timing of application, late sprays wheree disease is at high pressure may require higher rates. In some situations and in some seasons dryland sites may be more equivalent to irrigated sites. In dryland situations monitor rainfall between the key application timings at GS30, 32, 39 and 69 (early stem elongation end of flowering), where rainfall is welll above the average consider irrigated strategy options as well as dryland options. Use of rates lower than the full label rate is done at the grower s own risk. 3

4 CROPS am 8.30pm Wed 5 th December 2012 Chertsey Arable Site FAR s annual Crops Expo is only a few days away and the site at Chertsey is looking fantastic! Amongst the plots on show this year will be trials on the effect of N on milling wheat, late season management of ryegrass, managing white clover bulk and the efficacy of new fungicides on barley. Also on show will be trials from platinum agronomy sponsors PGG Wrightson, Dow Agrosciences, Agronica, Syngenta, Bayer Crop Science, and BASF, and of course, demonstrationss by platinum machinery sponsors CASE IH, Power Farming and CB Norwood. As in previous years there will be a mixture of scheduled talks and demonstrationss as well as plenty of time to view sponsors sites and chat to presenters one on one. The field day will conclude at 5.30pm followed by drinks and a spit roast dinner. All levy payers should have received an invitation and entry tickets, if you have missed out, please contact us. We look forward to welcoming you to this event. 2. Have you seen Septoria tritici (Speckled Leaf Blotch) in your wheat crops? Reminder: We are looking for samples of this disease on wheat leaves to send to Europe in order to assess how sensitive this disease is to our commonly used fungicides (triazoles and strobilurins). If we can get around 50 samples of the disease from across the country it will give us an update on the sensitivity of this disease to fungicides. Pleasee send us a sample of Septoria tritici from your crop! Once the samples have been collected Syngenta have offered to send samples to Switzerland for testing in order to get on updated view on the statuss of this disease. What does Septoria tritici infection look like? 4

5 Septoria tritici is very distinct as the necrotic lesions on the leaf have black fruiting bodies (pcynidia) which are visible to the naked eye. Do not send samples unless they have clearly visible black pycnidia. Sending a sample what s involved? Just send us a sample of 20 infected leaves (taken from across the paddock) showing Septoria tritici infection. Put the leaves into a paper envelope and let them dry overnight. Then post them to: Septoria Sample Foundation for Arable Research PO Box Templeton Christchurch, 8445 Please do not put any samples into plastic bags use only paper envelopes. You can send samples from treated crops (or untreated crops/trial plots) but: do not take samples from paddocks which have been sprayed in the last 10 days clearly state what fungicide the crop has been sprayed with. Why is it important to know the level of sensitivity to fungicides in New Zealand? In Europe where this disease has been more problematic, there has been a decline in sensitivity of this disease to triazole fungicides as well as resistance development to strobilurins. Though this disease is not as prevalent heree in New Zealand, things could change due to wetter spring weather, earlier sowing or new cultivars. This testing willl give us an update on where New Zealand standss in terms of sensitivity compared to other parts of the world. Thanking you for your anticipated help. Nick Poole, Director of Research and Extension. 5

6 Septoria triticii sample form Sample Collector and location: Name: Company: Address: Location where sample collected: Crop: Cultivar: Last fungicide crop treated with: (Product/Timing/Date) Date sample collected: Additional Notes: It is intended that the results from all the fungicide sensitivity to this disease. samples will be grouped together to give an update on Please do not use plastic wrapping or plastic bags of any kind to send samples. We only need infected leaves, not whole plants in paper envelopes. Contact us Rob Craigie Richard Chynoweth NOTE : This FAR Crop Action Report was prepared with current information at the time of publication. Neither FAR or its staff may be held liable for any crop damage or loss from interpretation of the information contained within this or any edition of Crop Action. Information contained in this Crop Action is intended as a guide only.. All previous Crop Actions and other publications can be viewed on the FAR website Please contact the FAR office if do not wish to receive this and advise if you change your address 6