Planting & Establishment

Transcription

1 Rative Yield Cotton Planting and Establishment: Achieving even establishment of a cotton crop is critical in getting the crop off to a good start; as it can influence how the crop is to be managed. The aim for every cotton grower should be to plant the crop once, achieve the desired plant stand and evenness and get the crop off to a great start. Many little things go into the planting operation, combining to culminate a successful planting and establishment, and each is important, because a problem with any can affect the establishment and impact on the performance of the cotton crop through the entire season. Seed Requirements and Quality: Have your seed on farm ready to go. Discuss your requirements with your preferred CSD Agent prior to planting in relation to quantities and timing to ensure you are not waiting for seed to be delivered. Check that the seed quantities delivered match what was ordered and update seed and seed size information to fine tune planting rate. Cotton Seed Distributors takes great pride in providing the highest quality cotton planting seed to the Australian cotton industry. To provide cotton growers and consultants with current information relating to seed quality and enable them to refine their planting operation to get the best Seed type and quality information are establishment. printed on the bag sticker. Important information located on the bag: Variety/Technology/Seed Treatment, although this may seem simplistic it is important to check to ensure that the correct seed goes into the correct field (green circle). The AUSLot number (red circle) is a critical number on the label. Information on percentages can be obtained by quoting this number to the CSD website. Knowing the actual percentage is useful in fine tuning planting rates.(this information is available at Ensure that all farm staff are aware of the chosen variety and technology for each field. Bag and Seed Seed Technology Type: Confusion may Colours occur due to Conventional Silver similarly named and Roundup Ready Flex Violet coloured varieties Bollgard 3 Roundup Ready Flex Blue across different Bollgard II/Roundup Ready Flex Blue technology groups. Bollgard II/Liberty Link Red CSD has tried to Liberty Link Gold alleviate this issue in a small way by having the bag and seed colour identical, based on the technology type. Please Note: that carry-over seed purchased in previous seasons may have different seed quality now and should be re-checked. CSD would encourage growers with farm stored seed to re-test the percentages to ensure seed viability and fine tune planting rates. Talk to your CSD Agent to get a re-testing kit. Many Variables Affect Cotton Establishment: The annual industry disease surveys conducted by CSD, QDAF and NSW DPI offer a snapshot of seeding mortality (Figure 1). Seedling mortality is a relationship of the plants established to those planted, it takes into account all variables which may affect establishment; such as seed percentages, soil insects and not only seedling disease. Increasing the seed rate to compensate for adverse conditions at planting is a cost effective measure, providing insurance on achieving a uniform stand. Factors Affecting Bourke/Walgett Establishment: Planting Rate: The CSD Extension and Darling Downs St George Theodore Development team Emerald stresses the importance Burdekin of establishing a 1 3 uniformly spaced plant % Seedling Mortality stand. A uniform plant stand is more critical than the actual number of plants per metre. However, there are more disadvantages with having a plant stand which is too low than too high, and depending on season length it can be critical. Select an established plant population that you are comfortable with which suits your soil type, water availability and management. Remember, your plant stand is one variable which is very difficult to change or adjust post planting. The CSD E&D Team recommend a Figure 1: Average Regional Seedling Mortality Percentage Allen. et.al. Disease Surveys (Tandou - 2 seasons data) Tandou M'bidgee Lachlan Macquarie Namoi Gwydir Macintyre Figure 2: Relative yield of combined CSD irrigated and dryland plant population trials (accumulated data from 28 irrigated and 9 dryland trials across various regions) Dryland Irrigated

2 uniform plant population of 1 to 12 plants/m. Consistently across plant population trials, a plant population above 8 plants/m has not shown a significant difference in the final yield of the crop, as shown in Figure 2. Gaps greater than 5cm can limit yield potential of the crop, which can lead to uneven maturity of plants and difficulties in managing fields for weeds, insects, growth regulators, defoliants, root cutting and picking. These gaps are further exaggerated in wider planting row configurations where neighboring rows may be too distant for compensation. The CSD E&D Team have developed a Cotton Planting Rate Calculator hosted on the website. This tool is designed to assist cotton growers and consultants to fine tune seed planting rates depending on localized conditions and influences on seedling mortality. It encapsulates many of the variables the CSD E&D consider when determining planting rates to achieve the desired established plant stand. From many season of learnings from CSD Agronomy trials and the CSD Ambassador Network fields. Factors Which Lead to Increased Seedling Mortality: Bed Conditions: Uneven or cloddy conditions can result in uneven seed placement, poor soil/seed and moisture contact, resulting in staggered and gappy stands. In watered up situations, seed movement deeper into the soil profile has also been recorded. Uneven planting depth can be exacerbated by planting at too fast a speed for the conditions, causing excessive bounce and vibration in the planter unit and an uneven traverse across the field. The amount of stubble cover, cotton trash and its fate post the planter passing will also have impacts on seed establishment. Worst case scenarios are when trash falls into the planting slot. Ensure options such as trash wipers are benefiting the planting operation as required. Planting Depth: Seed placement depends on the intended method of establishment of the crop. Thus planting depth is a balancing act to ensure adequate seed/soil moisture contact and minimising the time from to emergence. Establishment Method Ideal Depth When planting dry, it is Planting dry and watering up 2½ cm very important to be Planting into moisture (pre 2½ - 4½ cm aware of the consistency irrigated or rain moisture) of the seedbed. A cloddy hill can collapse when moisture arrives and the seed moves down to a greater depth than intended, resulting in a poor and variable strike. Soil Insects: Wireworm in particular, can attack young seedlings. Soil insect pests should be scouted prior to planting. Some seed treatment insecticides will control them but because the insect needs to feed on the plant before it dies, some plant stand loss can still occur. Special attention should be given to fields with high levels of cereal stubble or residual weeds. Seedling Diseases: Rhizotonia, Pythium and Fusarium can kill young plants during and after emergence. Black root rot slows crop development and reduces season length which must be allowed and compensated for. These diseases are more prevalent at lower temperatures, where there are high levels of cotton residue in the fields and in fields with a history of disease symptoms. Soil Temperature and Forecast: Temperature plays a Figure 3: Cotton Sensitivity to Cold Temperatures vital role in the rate of during Germination. development and of a cotton seedling. Below 12 C the growth of a cotton plant is severely retarded and enzymatic activity within the cotton plant does not function properly until temperatures are above 15 C. There is a strong relationship between time to establishment and soil temperature, with the higher the temperature the faster the rate of development and. Cotton is a temperature sensitive crop and the way the crop deals with the extremes of temperature is by shutting down or slowing physiological processes in the plant Temperature experienced post planting will also have an impact on the time taken for the plant to emerge. The slower the plant grows, the greater the chance of seedling death occurring through disease and insect damage. Figure 3 shows the critical times of an early seedling s life in terms of sensitivity to temperature. This is why it is so important to monitor soil and air temperatures to find the appropriate window to plant the crop. It has been an Australian cotton industry guideline for many years that cotton planting should not begin before soil temperatures reach 14 C or above at 1 cm depth, at 8.am. Planting at temperatures below this will diminish root and shoot growth, reduce water and nutrient uptake and make plants much more susceptible to attack from seedling diseases and insects. In some of the southern growing regions, it can be difficult to reach these temperatures in early October and therefore a forecast for rising air temperature and hence soil temperature will allow growers to start planting. The following guidelines should be

3 Germination % Germination % considered when determining if conditions are suitable for planting cotton. Before entering the field ask yourself the question: 1. If you cannot give a green tick next to at least one of these statements, then planting conditions are definitely unsuitable - STOP! 2. If you can give a green tick to only one of these statements - BE CAUTIOUS. Adjustments may need to be made. 3. If you can give both statements a green tick - Let s GO! Soil Temperature and Forecast now on Faststart Cotton and CSD Web Site: Cotton Seed Distributors have launched this season an expanded, real time soil temperature network spanning the entire Australian cotton industry. Funded from the FastStart Research Fund which is a collaboration between CSD and Syngenta. The results of the 33 soil temperature probes are displayed at or at Hourly temperature results are displayed as well as a forecast of the air temperature for the following week. The CSD E&D team encourages cotton growers and consultants to use this soil temperature network to refine and customise cotton planting timing decisions. Temperature Effects on Speed of Germination: There is a strong relationship between time to establishment and soil temperature, with the higher the temperature the faster the rate of development and. A faster rate of development is desired, as the cotton plant emerges faster and starts to generate its own energy from sunlight. Root growth is rapid, minimising the influence of pest and disease pathogens and allows for the developing root to be firmly footed in soil moisture. In 14 the CSD E&D team conducted a laboratory study into the effect of temperature on two different AUSlots of Sicot 74BRF with differing percentages. In an aim to get differentiation between treatments we used nonstandard parameters of as a result of a 2mm radicle emergence at regular intervals, as previous attempts at standardised tests were not sensitive enough to record differences. Results are shown in Figure 4 where there is considerable difference between the rates of development at different temperature regimes. Note that the seed in the 12- o C regime took 4 days before a 2mm radicle was witnessed. Thus in field conditions this seed would have been exposed to soil pathogens and pests in a vulnerable state. Importantly, there is very little difference between the rates of development between the two seed AUS lots regardless of either the warm or cool percentages. The take home message from this is that cotton Table 1: Effect of temperature on cotton seedling survival and growth rate. (Constable and Shaw 1988) Min Soil temp at 1cm Seeds Emerging and Survival Days to Complete Emergence 1 56% % % 5 Figure 4: Effect of cyclic temperature regimes on Sicot 74BRF speed. Sicot 74BRF 7 Day Cool Germ =, 7 Day Warm Germ = oC oC 14-22oC 1 12-oC 24hr 42hr 48hr 72hr 96hr 1hr Sicot 74BRF 7 Day Cool Germ = 93, 7 Day Warm Germ = 96-3oC 16-24oC 14-22oC 12-oC 24hr 42hr 48hr 72hr 96hr 1hr

4 Establishment Percentage Establishment Percentage Planter Variability Index is temperature dependent and planting into cooler conditions is going to slow the rate of progress of the young cotton plant. CSD is now providing additional high quality 7-day cool data. The differentiation of the cool and warm tests means that more information is supplied than in the past and gives a greater level of transparency and allows growers and consultants to make more informed decisions. Achieving even establishment of a cotton crop is critical in getting the crop off to a good start; it can influence how the crop is to be managed. The aim for every cotton grower should be to plant the crop once, achieve the desired plant stand and evenness and get the crop off to the best possible start. Many little things go into the planting operation, combining to culminate a successful planting and establishment, and each is important, because a problem with any can affect the establishment and impact of the performance of the cotton crop through the entire season. There are many aspects within the successful planting operation which farm management can have an influence on. Field and Bed Conditions at Planting: This past season the CSD E&D team concentrated on the seed bed conditions growers were planting into and in the coming seasons we are partnering with CSIRO through the FastStart Research fund to objectively determine what the ideal conditions to plant into are. Measurements will be taken examining soil strength, dispersion potential, stubble and trash levels, clod size and distribution, moisture content and bed consolidation. Figure 5: Range of establishment results for differing planting dates for CSD Ambassador Network. % % % % % % Figure 6: Effect of planting conditions on establishment. % % % What was witnessed with the % same seed lot, was a considerable variation in the % establishment achieved by % growers within the CSD Ambassador Network. Figure Field Condition Score 5 shows the establishment results from 42 crops ranging from 22% to 94%, and a similar range was seen in the variety trial fields from the previous season and highlights that there are many factors which positively and negatively influence the final establishment achieved. Fields within the CSD Ambassador Network were subjectively scored on a scale of 1-5 for seed bed conditions. One being; ideal conditions, good 6/Sep /Sep 4/Oct 18/Oct 1/Nov 15/Nov 29/Nov consolidated beds with consistent small clod size, free of weeds and stubble. Whereas five was for back to back conditions with large clods and heavy loads of trash on the surface. When the scores were plotted against establishment percentage there was a relationship with the higher establishment in better seed bed conditions as seen in Figure 6. It should be noted although the overall trend is negative there is a lot of variability in the establishment results especially at level 2 and 3, inferring further influences on establishment. Planting Uniformity: One thing that the CSD E&D team has stressed is that a uniform plant Figure 7: Relationship between stand is desirable. Last season final establishment & the planter we examined how uniformly variability index. cotton was established across 5 the planter unit. There was a considerable range across the 4 CSD Ambassador Network. A 3 planter variability index of zero indicates that every row across 2 the planter has the same plant 1 population, the higher the number the greater the variability across the planter. % % % % % % Final Establishment Figure 7 shows the relationship between the final crop establishment and the planter variability index. The data from last season suggests that the more uniform the planter the higher overall establishment. Planter Setup: A Simple Checklist Spend some time on setting up, to ensure that everything is functioning correctly. Breakdowns in the field will rob you of time and allow valuable surface soil moisture to further dry away. Level The Planter Check Bushings & Parallel Linkages Drive Chains and Cogs Disc Openers Calibrate Seed Rate and Meters Seed Tubes Press Wheels Horizontally/vertically level tool bar or have it run slightly down hill Parallelograms during planting should be horizontal or slightly below tool bar height Reduce bounce & lateral movement in planter unit Remove kinks & ensure lubricated and running true Ensure even wear and good contact Ensure mud scrapers are on and aligned Ensure correct seeding plates and baffle is in the correct setting Calibrate seeding rate & monitor performance Replace worn or faulty tubes Ensure monitor sensors are securely fastened & cleaned Replace redundant ball bearings & rubber tires

5 Establishment % Trash Wipers Ensure that press wheels line up on planting disc slot Ensure level across planter unit Rotate and replace redundant ball bearings Ensure level across planter Spray Lines Ensure spray lines, nozzles & filters are clean Calibrate herbicides, in-furrow insecticides, water and chemical rates Seeding rates should be calibrated prior to entering the field, pay attention to Sicot 74BRF, Sicot 746B3F, Sicot 748B3F and Sicot 754B3F which has a much lower seed density. Keep a kit of spare parts and essential tools (seed tubes, press wheels, scrapers, monitor cables, chains, nozzles and nozzle and debris brushes) handy in the cabin or on the rig to allow for quick minor repairs to minimize down time. Use "Synchrony 746" powder in the planter boxes according to manufacturer s recommendation to assist with seed flow. During the operation, regularly check seed depth and the condition of the soil around the seed. This is especially important when planting on rain moisture or where encountering variability across fields and hills. Planting Depth: Seed placement depends on the intended method of establishment of the crop. Thus planting depth is a balancing act to ensure adequate seed/soil moisture contact and minimising the time from to emergence. When planting dry, it is very important to be aware of the consistency of the seedbed. A cloddy hill can collapse Establishment Method Planting dry and watering up Planting into moisture (pre irrigated or rain moisture) Ideal Depth 2½ cm 2½ - 4½ cm when moisture arrives and the seed moves down to a greater depth than intended, resulting in a poor and variable strike. The depth you want your seeds depends on the method and soil conditions you are intending to establish your crop. Many people like to use the "knuckle" as a quick and easy measurement tool in the field. Some dry soil above the seed slot is useful to prevent losing moisture from around the seed, but if there is too much, a rainfall event after planting will turn this dry soil wet, and increase the depth of soil for which the young seedling needs to push through. Check the consistency of the soil above the seed. If the pressure from the press wheels on the planter are set too high, you can get a compacted zone above the seed and young seedlings will have a tough time emerging. A study undertaken in 14 by the CSD E&D team conducted a controlled temperature environment where Sicot 74BRF was subjected to two regimes, a 3/oC cyclic and 18oC constant temperature. Superimposed on these temperatures were different planting depths in sand filled growth pots varying from 2 to 8 cm in depth. The results are shown in Figure 8 from which we can deduce a couple of points. Figure 8: Interaction between planting 1. A higher temperature depth and temperature on cotton regime resulted in establishment. significantly improved cotton establishment. 2. At a depth of greater than 5cm establish is 18C 3/C compromised even under ideal conditions. This is exacerbated at cooler temperatures. 3. It took 13 days for the 2cm depth under the 18oC to establish % of seeds 4. It is possible to compensate for deeper planting at higher temperatures. Planting Speed: Planting operation is one of the most important tasks that growers undertake. It should result in a desired stand that emerges quickly and uniformly. One of the keys to uniformity is planter speed. "The aim should be to plant with precision not speed." Cotton planter speed trials were conducted by the CSD E&D team in 13 to look at the effect on establishment using commercial planters at varying speeds. Figure 9: Effect of planter speed on cotton establishment. All sites varied in soil type, moisture, rotational crop stubble cover, depth, disease and insect pressure, weather conditions and geographical locations (north to south). The only consistent variable in each trial was speed. That way "speed of planting" could be seen to be the only contributing factor to any difference in establishment at each trial Depth (cm) Each area had its own different seed drop (seed planting rate). The data represents the percentage loss from the initial seed drop. For example, if the treatment was planted at 1 seeds/metre and only 5 plants established for 1km/r, this would represent 5% establishment for 1km/hr. The data collected can be seen in Figure 9. The data shows that there is an ideal planting speed around 8-1km/hr. Outside this range the data shows that the average population decreases when the planter speed was increased to over 1 km/hr or below 8 km/hr. In watered up situations, planting speed had little effect on the final establishment, it is only in non-uniform conditions, overly cloddy or with high stubble or trash levels where we witnessed poorer establishment.