ICFR Field Day Focus: Wattle Research issues

Transcription

1 ICFR Wattle Field Day Thursday 23 rd October 2014 Venues: ICFR Nursery, Strathfieldsaye Farm and Eston Farmers Club Thanks are extended to SAWGU for sponsoring the catering

2 ICFR Field Day Focus: Wattle Research issues Date: Thursday 23 rd October 2014 Venue: ICFR Nursery & Eston Farmers Club Time: 08h15 for 08h40 GPS Co-ordinates: ICFR: S, E Eston Farmers Club: S, E 08h15 08h40 08h45 09h45-10h30 10h30-11h45 11h45 Meet for tea and coffee at the ICFR Nursery PROGRAMME Field Visits Welcome and objectives for the Wattle Focussed field day, including an overview of the issues Tour of Nursery and presentation on the results from the ICFR s vegetative propagation trials Travel to Strathfieldsaye Farm Field stops to sites to see wattle rust damage Travel to Beaumont Eston Farmers Club Indoor Presentations Craig Norris Sascha Beck-Pay / Julian Chan Julian Chan / Craig Norris / Ant Foster 12h00 Overview of the wattle rust research programme Craig Norris NCT 12h10 The use of chemicals for the control of wattle rust Keith Little / Craig Norris 12h30 Progress on the wattle rust breeding trials Julian Chan ICFR 12h50 13h10 A study to understand and quantify the impact of wattle rust on the productivity of Acacia mearnsii in the KwaZulu-Natal Midlands LUNCH Thobile Mbatha 13h50 Update on wattle research and frost tolerance Julian Chan ICFR Wattle Industry ICFR ICFR / NCT NMMU / NCT ICFR 14h10 14h30 Long-term wattle fertiliser trial: Some early 6 th rotation results Developing a DNA finger printing protocol for Acacia mearnsii Louis Titshall Michael Bairu ICFR ICFR 14h50 End of Field Day Page 2 ICFR Wattle Field Day

3 Black Wattle vegetative propagation research at the ICFR Sascha Beck-Pay Institute for Commercial Forestry Research, PO Box , Scottsville, Pietermaritzburg, 3209 The development of rooted cutting protocols is fundamental to the Acacia Tree Improvement breeding programme at the ICFR, as this will enable the establishment of clonal seed orchards and thus increase genetic gain deployed from the breeding programme. Rooted cuttings will also play a major role in testing black wattle individuals, or hybrids, tolerant to wattle rust. A number of attempts at propagating black wattle through cuttings at the ICFR have been made over the years, but with limited success. The reasons for this can be attributed to a number of factors; however the most prominent one is the lack of a suitable rooting facility having close climate control. In 2013, the ICFR upgraded a greenhouse and converted it into a rooting tunnel. The facility has six heated tables which can be individually controlled and are driven by root plug temperature sensors. Soil moisture content is controlled by moisture probes which drive the misters within the tunnel. The tunnel conditions are maintained by a fan, foggers and misters to ensure that the humidity remains high yet at the same time the ambient temperature in the tunnel is held in a range. Maintaining such conditions, especially during the hot summer months, was a challenge, however, the installation of aluminet within the rooting tunnel had a dramatic effect in significantly reducing the ambient temperature. So much so that on some days temperatures of 50 o C have been recorded above the aluminet, whilst below the ambient temperature could be maintained at 24 o C. All the data from the sensors within the tunnel are logged to a Delta Programmable Logic Controller (PLC) and can be downloaded and viewed in excel. The conditions within the tunnel to ensure uniformity and consistency of the set conditions, together with preventing too much moisture are constantly are being monitored and optimised to ensure maximum rooting. The second most prominent reason for the poor rooting of black wattle cuttings at the ICFR was that there has not been a concerted research effort in this area. After the establishment of the rooting tunnel at the ICFR in 2013, research into vegetative propagation of black wattle was initiated. A number of experiments have and are being conducted to try improve the strike rate of cuttings from both adult trees in the field and from hedge plants. Preliminary results have shown that cuttings taken from hedges as opposed to cuttings from mature trees, can yield a 10-15% increase in rooting. Dependant on season, an average of 24 to 31% rooting has been recorded from hedge plants with some genotypes giving as much as 85% rooting and others, zero rooting. We believe average rooting percentage from hedges has the potential to increase to 40% by applying the results from the research being conducted at the ICFR. The effect of hedge plant age, size, condition and nutrition could also accelerate this strike rate. Experiments are also being conducted into improving the aftercare of rooted cuttings once they have been removed from the rooting tunnel. The root architecture and time of nodule initiation of rooted cuttings are also being investigated as these are important characteristics for cuttings, as the better the root system the more robust the cuttings will be in the field. Acacia, being a legume, forms a symbiosis with nitrogen-fixing bacteria called rhizobium. The rhizobium produces nodules which are the site of nitrogen-fixation. It is due to this ability to produce nitrogen-fixing nodules even in nitrogen deficient soils, that the genus is often used in agroforestry or for crop-rotation to restore the soil fertility. The sooner nodules are produced the greater the benefits with regards to plant quality and growth. Hedge plant management is a critical area of research which is directly related to rooting. It is important to be able to know how long hedges can remain productive for, what the productivity of hedges are, and how this relates to nutrition, age, size and season. Rooting fluctuates across the seasons and thus part of the research into hedge plant management at the ICFR is the seasonal variation in rooting cuttings from selected hedges of different ages and sizes. The nutritional status of these hedge plants is also being tracked, to ensure suitable management of the hedge plants with maximum productivity and rooting. In the past, black wattle was considered very difficult to root and certainly not commercially viable but with a dedicated research effort together with a high performance research rooting tunnel, the impossible is becoming possible. Page 3 ICFR Wattle Field Day

4 Wattle rust research programme Craig Norris NCT Co-operative Ltd, P O Box 1445, Pietermaritzburg, 3200 The Wattle Plantation Industry is being severely affected by a serious new rust disease. The pathogen has been identified by the Tree Protection Co-operative Programme (TPCP) as an Uromucladium spp. and is specific to Acacia mearnsii (black wattle). The rust was first described at the end of 2013 and has spread rapidly to affect an estimated area of about hectares. The pathogen infects trees of all age classes and results in trees dropping their leaves and die back of growing shoots. In extreme cases severely affected compartments show mortality of up to 30% of trees. It is anticipated that this rust will spread to the majority of wattle plantations during the 2014/15 summer months and thus poses a serious risk to the Industry. A Wattle Rust Steering Committee has been formed to identify and support various research initiatives. Projects, including budgets, have been documented and the Committee is in the process of sourcing funding. The projects include work on: Biology and epidemiology Monitoring, detection and risk prediction Impact assessment and disease development Development of a resistant breeding population Propagation of resistant material by cuttings Chemical control (registration and protocols) Page 4 ICFR Wattle Field Day

5 The use of chemicals for the control of Wattle rust Keith Little 1 and Craig Norris 1 keith.little@nmmu.ac.za Nelson Mandela Metropolitan University, P O Box 77000, Port Elizabeth, 6031 Due to the recent occurrence of wattle rust, there are currently no chemical products that have been registered in South Africa for its management. In the short-term, the use of a suitably registered chemical will probably be the most effective manner for control. As other control methods (biological and cultural) become available, any chemical control technology can then be incorporated into a more integrated management strategy. Due to any environmental and social issues associated with forest chemical use, the testing of any existing, new or alternative products must be carried out in conjunction with the South African Timber Industry Pesticide Working Group (TIPWG) to ensure that they meet current and future certification standards as used by certification bodies (for example the Forest Stewardship Council). Only those products that are currently acceptable and likely to remain acceptable into the future will be tested. The selected chemical products will need to be screened to determine: Seedling/tree phytotoxicity; Impact on target (in this case wattle rust); and A combination of phytotoxicity and impact on target. This component of the presentation will highlight the proposed research to be conducted in the following three areas from : 1. Initial screening of chemical products for potential registration; 2. Refinement of application methods for the cost-effective chemical management of wattle rust; 3. The incorporation of chemical use into an Integrated Pest Management plan Results from these trials will be used by the chemical company involved for registration purposes. Page 5 ICFR Wattle Field Day

6 Wattle rust Progress on the wattle rust breeding trials Julian Moreno Chan Institute for Commercial Forestry Research, P O Box , Scottsville, Pietermaritzburg, 3209 Breeding for the wattle rust disease Breeding for tolerance to the wattle rust disease Julian Chan Eston Wattle Field Day, 23 October2014 UCL Harden Heights progeny trials Results assessment May 2014 Mortality due to the rust Rust incidence (% trees with symptoms) as a measure of resistance to the disease Tolerance to the rust (disease rating scale) Preliminary genetic results Take home messages Progeny trials UCL Harden Heights UCL trials - overall survival & mortality May 2014 Trial Genetic groups No. Fam & controls Size (ha) Planting date Survival Feb (before rust) BGA F1 SP2, SP Dec % BGA -Dend SP1, SP6, SFC Dec % BGB F0&F1 SP4, Aus 1985, Sherry Jan % Trial Group No. Fam Survival Mortality (%) (%) Total Rust 1 Herbicide Other BGA F1 SP SP BGA Dend SP SP SFC BGB F0F1 SP Aus Sherry Controls Old BP F Old BP F Unimproved PSO Combined effects rust + insects Mortality due to the rust + insects ranged 0 12% Highest levels: groups SP2 and SP5 Lowest levels: SP4 and Australian introductions 1957 & 1985 Genetic material most recently introduced to SA showed lowest mortality due to the rust + insects (for this assessment) Progeny trials UCL Harden Heights - May 2014 assessment Rust incidence (%) across genetic groups and controls Rust resistance preliminary genetic results With exception of trial BGA Dend, where h 2 f was moderate (0.37), genetic parameters and heritabilities were poor Difficult to obtain good genetic parameters for a binary trait with average incidence levels <0.3 or >0.7, which are also associated to high environmental variance (error, noise) (Isik et al. 2008, Isik 2011, Lynch and Walsh 1998, Gilmour et al. 1985) This was in agreement with the very high variance components obtained for rep*fam and the residual Better results trial BGA Dend related to shape (~square) and smaller size of this trial relative to the others, i.e. pathogen levels (spores) more uniform? Whereas BGA F1 and BGB F0F1 are long rectangles, thus irregular spore levels and more environmental noise? It s possible to improve genetic results in future trials if trial design is better adapted to the disease; e.g. single-tree plots, trial shape, closer spacing 0 Aus 1985 SP4 Sherry 1957 Con PSO5 Con Old BP Con Old BP Con F0 F1 Unimproved SP6 SP1 SFC SP2 SP5 Page 6 ICFR Wattle Field Day

7 Rust tolerance Score = 4 Score Description 0 Disease not present 1 Light 2 Moderate 3 Severe 4 Very severe Score = 0 Score = 2 Score = 3 Rust tolerance preliminary genetic results Good results for the BGA Dend trial (h 2 i=0.20 and h 2 f =0.56) Poor results for the other two trials Better results for the BGA Dend trial confirmed less environmental noise in this trial and perhaps more uniform spore levels (as observed in the rust resistance results) Coincidentally, this is the trial with the highest levels of improvement for traits of economic importance Thus can use material to select for both resistance and tolerance to the rust (at the family level) Take home messages - breeding results so far Results so far are from the first assessment Trials were not designed for the disease, accuracy and genetic parameters/heritability will improve with next trial series Resistance levels are very low, inconclusive if resistance is genetically controlled Tolerance, on the other hand, is more promising and seems to be heritable For one of the trials (BGA Dend), it s possible to select for both resistance and tolerance at the family level Coincidentally, this is the trial with the highest levels of improvement for traits of economic importance For the trial BGB F0F1, it s possible to select for tolerance at the family level Use selected material to establish seed orchards In the shorter term, selected material can be used for the clonal project NCT screening trial preliminary results assessment 3 June 2014 Trial planted 28 Feb 2014, Eston KZN Groups No disease Disease levels (% trees) Light Moderate BGA F BGA Dend BGB F0&F Results at Eston confirmed general trend observed at the UCL trials The lowest overall susceptibility was for group BGB F0-F1 = Australian introductions 1957 & 1985 (50% trees showed no signs of the disease) Two subgroups of SA base material similar results, much higher susceptibility than the Australian material (although disease levels were light) Page 7 ICFR Wattle Field Day

8 A study to understand and quantify the impact of wattle rust on the productivity of Acacia mearnsii in the KwaZulu-Natal Midlands Thobile Mbatha Institute for Commercial Forestry Research, P O Box , Scottsville, Pietermaritzburg, 3209 Acacia mearnsii (black wattle) is grown in South Africa, particularly for its demand as high quality timber for the pulp industry and for its tannin-rich bark. In addition, it is also used for mining timber, fuel wood and has uses in creating wind breaks and soil reclamation. In South Africa, about ha is planted with Acacia mearnsii, contributing 7.4% to the timber and pulp market. Black wattle also contributes to the livelihoods of rural communities, as they rely on unmanaged wattle stands and woodlots, particularly for fuel wood and building timber. It is therefore important to maintain a sustainable production of black wattle and try to mitigate any risk threatening to its productivity. Recently, a new disease of black wattle, caused by a rust fungus, has been discovered in the KwaZulu- Natal Midlands region. Although the identity of the pathogen has not yet been confirmed, work is in progress by the Forestry and Agricultural Biotechnology Institute (FABI, University of Pretoria) to determine the species of the rust fungus. Since little is known about this new pathogen in terms of its biology, epidemiology, and impact on productivity, a multi-faceted project, with various academic and industry partners, has recently been initiated to gain the necessary knowledge to effectively deal with this problem. Thus, the main aims of this project are to: (i) Determine the impact of wattle rust on black wattle growth and productivity; (ii) Understand the interaction between wattle rust and co-occurring pests and their impact; (iii) Relate the levels infestations to environmental factors and identify triggers of outbreaks; and (iv) Provide ground-truthing points for calibration of remote sensing monitoring of the disease incidence. To achieve these aims, FABI and the ICFR are currently engaged with two complementary field-based studies designed as follows: (i) Three exclusion plot trials implemented to quantify impact of wattle rust on black wattle growth and productivity. (ii) Twelve monitoring sites selected to understand the interactions between host/pathogen and environment and identify environmental triggers of the outbreak. This presentation will highlight important aspects of these two studies and provide some feedback on the most recent progress of the trials. Page 8 ICFR Wattle Field Day

9 Update on wattle research and frost tolerance Julian Moreno Chan Institute for Commercial Forestry Research, P.O. Box , Scottsville, Pietermaritzburg, 3209 Improvement for frost tolerance in black wattle Breeding for frost tolerance and development of interim sources of frost tolerant seed Julian Chan Eston Wattle Field Day, 23 October2014 SA base population (Vanderplank and others) Victorian origin, not particularly frost tolerant (Nixon and Brain, 1988) SA large temperature gradient (T max - min) in the winter months Problem aggravated since 1970s when improved seed became available, farmers started planting seedlings in stands previously re-established by natural regeneration or line sowing Advantage of these systems over planted seedlings is the very high initial stocking which ensures acceptable survival after frost occurs Only proven sources of frost tolerance material came from the Australian introductions 1957 & 1985 tested in very cold sites Mpumalanga In particular two provenances from collection 1985 (Lake George and Mittagong), and one seedlot from collection 1957 (Cooma) Only 8-20 seedlots from collection 1957 were tested (out of 38 seedlots -old seed archives) Previous trials failed to identify best families and individuals to continue breeding process, breeding efforts remained at the provenance level Improvement for frost tolerance in black wattle Re-prioritize interim sources of frost tolerant seed for the Industry (Sheepmoor and Liff) Breeding plan for Sheepmoor Very small amount of seed available, yet this is the best proven source of frost tolerant seed Sweeping Sep 2014, seed processing underway Propagate trees by cuttings and establish un-pedigreed clonal orchard(s) from 2015 Establish un-pedigreed seedling seed orchard(s) from seed collected from Sheepmoor Manage those orchards to accelerate seed production Thinning of Liff (Karkloof) and conversion to a seed orchard Conversion completed June July Sweeping will take place from October 2014 About 200 kg seed are anticipated which can be split into 50 kg per year until next sweeping Note this seed is not appropriate for extreme cold sites (e.g. Iswepe), but for moderately frost sites Improvement for frost tolerance in black wattle (cont.) Although field testing is obscured by other factors such as drought etc., this will continue until artificial screening methods are developed for A. mearnsii A field trial was planted at Iswepe in Feb A second trial is planned for Jan Frost tolerant material identified in both trials will be used in two ways: Parent trees available at Liff (backward selection) propagate and establish in clonal orchards Establish 2-3 BSOs in intermediate frost region (e.g. Vryheid, Commondale). The BSOs will provide selections for the next generation of improvement (improve traits of economic importance in frost tolerant material) Medium-long term Investigate screening by artificial freezing in Acacia mearnsii (Pollock et al., 1986; Searle et al., 1998). MSc project with Wits University (will require additional funding) Import seed from Australian provenances that have not yet been tested in South Africa, and that have shown frost tolerance elsewhere (e.g. cold sites China) Develop biochemical markers for screening frost tolerance material (see separate research project) Field screening trial Iswepe Type of test Progeny/Frost screening test Location Springbok Kraal, Iswepe Land owner Eckhardt Paul Altitude 1395 m Trial design Randomised complete block design 53 treatments, 2 controls 6 reps, 6-tree plots Spacing 3 x 2 m Date planted Feb 2014 Assessments 1) Initial survival & blanking 2) Before first frost (24 April 2014) 3) Mid winter (17-18 June 2014) 4) Post winter (3-4 September 2014) Temperature monitoring ibuttons, every 20 min, from 24 April 20 Aug Field screening trial 2014 Iswepe (cont.) No. Fam Australian intro Lake George, NSW 10 Mittagong, NSW 5 Omeo Highway, Victoria 11 South of Bombala, NSW 13 Controls 2 Acacia dealbata 1 PSO 5 1 Sherry Between Cranbrook and Apslawn, Tasmania 2 Cooma, NSW 2 Goongerrah Creek, Victoria 1 Lal lal, Victoria 1 Moulting Bay Lagoon, Tasmania 1 Mt Nowa Nowa, Victoria 1 Ovens Valley, Victoria 1 Stowell, Victoria 3 Swansea, Tasmania 1 Yon Yango, Victoria 1 Grand Total 55 Page 9 ICFR Wattle Field Day

10 Frost damage assessment th June 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Frost tolerance trial Iswepe - overall survival (%) over time 86% 92% June 6-15th frost events T = - 9 C Drought March - Sep 3 Mar 24 April 17 June* 3 Sep* 90% June 20-25th T = -5-7 C July 6-12th T = C 14% Survival & frost damage measured shortly after extreme low T s in June 6-15 th Trees not killed immediately but showing foliage changes Scored frost damage based on 1) foliage changes (Pollock et al. 1986) and 2) extent of frost damage (ICFR) Useful measures of frost tolerance Foliage changes Score Description 0 Normal green 1 Light change, almost normal 2 Discoloured, pinnules closed and becoming desiccated 3 Pinnules closed and desiccated 4 Pinnules closed, very hard and desiccated, leaves curled, sometimes plant scorched Extent of damage Score Description 0 No damage 1 Top leaves damaged 2 Top half 2 Bottom half 4 Whole plant s leaves frosted 8.0 Frost tolerance trial Iswepe - assessment June 2014 Combined frost scores by fam 8.0 Frost tolerance trial Iswepe - assessment June 2014 Combined frost scores by Provenance A85-19 A85-16 A85-12 L (A dealb) A85-18 Sher 9-1 A85-17 A85-22 Sher 9-2 A85-15 A85-79 A85-20 A85-32 Sher 22 (bulk) A85-78 A85-21 A85-73 Sher 12-1 A85-13 A85-45 A85-28 A85-29 A85-76 A85-77 A85-80 A85-41 A85-31 Sher 8-1 A85-72 L2 7A (bulk) A85-40 L A85-42 Sher 24B (bulk) A85-24 A85-39 A85-43 Sher 23 (bulk) Sher 24A (bulk) A85-36 A85-75 A85-44 Sher 11-1 A85-38 L2 6 (bulk) A85-37 A85-74 PSO5 A85-33 Sher 15-1 A85-34 L2 7B (bulk) A85-35 A85-82 A85-81 Take home messages the ICFR is taking the correct steps to ensure supply of frost tolerant seed to the Wattle Industry Seed from Liff available early 2015 (moderate frost sites) Seed and seed orchards derived from Sheepmoor extreme frost sites BSOs from material being tested long term, but seed will be improved for volume, stem form, bark and tannin, etc. Screening methods will accelerate future breeding Page 10 ICFR Wattle Field Day

11 Long-term wattle fertiliser trial: Some early 6 th rotation results Louis Titshall louis.titshall@icfr.ukzn.ac.za Institute for Commercial Forestry Research, P.O. Box , Scottsville, Pietermaritzburg, 3209 Introduction In the late 1940 s a number of factorial fertiliser experiments were implemented to help develop and refine fertiliser application recommendations for wattle production. In most cases combinations of nitrogen, phosphorus, potassium and lime were tested. One of the trials (C2 at Bloemendal) was reimplemented for a further five rotations. The 6 th rotation was felled in early 2014 and this presentation provides some of the early results of various growth parameters assessed. Experimental overview This was a 34 factorial arranged in a quasi-latin square confounded in nine rows by nine columns. Table 1 presents a summary of historical fertiliser regimes used. Table 1. Overview of fertiliser regimes used for each rotation of the long-term wattle fertiliser trial at Bloemendal. Nitrogen (as Ammonium sulphate) Phosphorus (as Single Super Phosphate) Rotation 1 to 3 Rotation 4 Rotation 5 Rotation 6 kg ha-1 (g tree-1) 0, 25, 50 (0, 10.5, 21) None 0, 20, 40 (0, 8, 16) None Potassium (as KCl) 0, 60, 120 (0, 12.5, 25) 0, 30, 60 (0, 6, 12) None Lime Planting notes Dates 0, 5.6, 11.2 (as agricultural lime) Line sowing, thinned to ± 1400 R1: 1951 to 1961 R2: 1961 to 1971 R3:1971 to , 5.6, 11.2 (as dolomitic lime) None Seedling planted in pits, thinned to ± 1500 None Seedling planted in pits, never thinned (± 2400) Variates assessed DBH (converted to basal area), total height, volume, stocking, wet bark yield. Soil samples and bark samples for analysis also collected but not reported here. Results No significant residual interaction effects (p > 0.05). No significant main effects of N or K (p > 0.05). Some significant main effects of P and Lime (p < 0.05): Positive P responses for BA, height, volume. Negative lime response for BA, volume, stocking and wet bark yield. Page 11 ICFR Wattle Field Day

12 Some preliminary thoughts Liming negatively affects production for extended periods Do not lime wattle plantations. Evidence of residual P may offer opportunity to lower P fertilisation rates in the future. Past and current results do not indicate any benefit to nitrogen fertiliser. Re-application of potassium may be necessary to main nutrient balance. Acknowledgements SAWGU for funding, Gary Behn and staff for land and operational assistance, past and current ICFR staff involved with trial. Page 12 ICFR Wattle Field Day

13 Developing a DNA finger printing protocol for Acacia mearnsii Michael Bairu michael.bairu@icfr.ukzn.ac.za Institute for Commercial Forestry Research, P O Box , Scottsville, Pietermaritzburg, 3209 Acacia mearnsii de Wild (black wattle) is a commercially important forestry species in South Africa, grown for its bark and timber. Conventional breeding of black wattle in South Africa started in 1947 and relied on selection for quantitative and qualitative traits. The importance of molecular genetics and DNA-based characterisation of the breeding material to complement the conventional breeding was emphasised after an external review of the back wattle breeding programme at the ICFR in A decision was then made in 2012 to set up a molecular genetics laboratory at the ICFR for black wattle, with a defined objective of characterising the breeding material using DNA fingerprinting methods. Since then, an SSR-based DNA fingerprinting protocol has being developed in the laboratory and progress on the development of the protocol will be discussed. Page 13 ICFR Wattle Field Day