Off-season activities: importance of planning and management

Farming follows an annual production cycle that aligns with the seasons, which means the farmer’s tasks change with the seasons: planting in spring, nurturing crops in summer, harvesting in autumn and early winter, and planning and maintenance in winter.

While some producers are still harvesting, others are already thinking about the next season and what needs to happen before the next crop is planted.

After the harvest and before the planting of summer crops, there are several important tasks that need to receive attention before the upcoming growing season. However, as each farm is unique, these tasks should be tailored to fit each one’s specific needs and circumstances.

It is also important to schedule your off-season activities to ensure one season does not simply run into the next, advises Hendrik van Staden, business head for Syngenta’s seeds unit in sub-Saharan Africa. “Identify specific areas to focus your efforts on and execute your off-season plan effectively,” he adds.

Some of the aspects that need attention include:

General maintenance. This includes repairing fences, buildings and machinery. It’s also a good time for hedging, planting trees, and ditch and drainage clearance.

Soil management. Conduct soil tests to determine nutrient and pH levels to determine
if any amendments are needed, and plan fertilisation accordingly. Apply manure, compost or other organic matter and chemical nutrients to improve soil fertility. After the harvest, consider planting cover crops if you haven’t already done so. These can be planted to manage nutrients, prevent soil, wind, and water erosion, and conserve moisture. Overall, cover crops help prevent soil erosion, suppress weeds and improve soil health.

Pest and weed control. Manage any pests or weeds that could affect the next crop. This may involve mechanical control, such as ploughing to disrupt the life cycle of pests and weeds, or applying herbicides if and where necessary.

Planning. Off-season planning on a farm is crucial for maximising productivity and efficiency in the upcoming seasons. It also helps with managing resources and timing for the next planting season.

Reflect on the past season to identify what worked well and what did not. Analyse the collected data and compare it with your records to enable you to make informed decisions for improvements. Do final planning and adjustments on crop rotation, select seed varieties, and order seeds in advance.

Equipment and farm maintenance. Service and repair farm machinery and equipment, especially planting equipment, to ensure they are in good condition and ready for use during the busy planting season. Inspect and maintain farm buildings and infrastructure, and plan any necessary construction or renovation projects.

Financial planning. Review financial statements and plan your budget for the next season. Explore opportunities for financial growth and cost-saving measures.
Marketing and sales. These are year-round activities, but it is wise to revisit them in quieter times to ensure you are following the best options.

Personal development. Take time to rest and recharge before the busy planting season begins. It is also a good time to set personal goals. These tasks help ensure that the farm is in good condition and the soil is ready for planting summer crops. It is important to tailor these activities to the specific needs of your farm, considering factors like climate, soil type and local agricultural practices.

Importance of soil sampling, testing

“Soil testing and sampling is of particular importance,” says Dr Driekie Fourie, world-renowned nematologist, technical product lead at Syngenta Seedcare in South Africa, and extraordinary professor at North-West University.

“To get a complete picture of what is going on in your fields, you must look at what is happening in the soil. When done right, soil testing can provide a representative snapshot across fields, providing farmers with critical information to make their best management decisions.

Soil sampling is thus of the utmost importance. It measures a broad scope of chemical, biological and physical soil characteristics, giving farmers a greater insight into the health of their soils and crop systems.

“With soil testing, farmers can measure soil pH, organic matter, microbial activity, and the prevalence of soil-borne diseases and insects,” she explains.

Fourie says one of the important benefits of timeous soil sampling is the opportunity to test for nematodes. “The best and only way to protect your harvest is to know what you are dealing with even before you plant the next crop. That is why farmers should take soil and plant samples at the best time, but also in the correct manner.”

Depending on the crop that is growing during such sampling, plant samples may include roots (barley, dry bean, maize, potato, soya bean, sunflower, wheat), tubers (potato, sweet potato), pods or seeds (Bambara nut, groundnut) and/or others.

Some plant-parasitic nematode pests infect the aerial parts of food crops like barley, garlic, onion and wheat, while the same applies to floriculture crops (flowers) and grasses. Therefore, stems, leaves and seeds of such crops should also be sampled for analysis to make sure of the status of nematode infection.

“Nematodes are the most economically important plant pests worldwide. They are responsible for approximately 14% of crop losses globally, and this constitutes a value of some $125 billion (about R2,3 billion) annually.

“Often farmers treat visible pests and diseases because they can see them and know how to deal with them. But with nematodes, it is more difficult. Nematodes operate below the soil surface and they are very small and generally invisible to the naked eye. But although they are small, they can cause severe crop losses,” says Fourie.

“Three of the most important nematode species that have a major impact on agriculture in South Africa include root-knot nematodes (Meloidogyne spp.), cyst nematodes (Globodera spp. and Heterodera spp.) and lesion nematodes (Pratylenchus spp.),” she points out.

“What exacerbates the situation is that various nematode species simultaneously occur in crop fields, causing significant damage to the crops and subsequent yield losses. In high population densities, nematodes can cause discoloration of leaves and have a negative impact on root and crop development,” she explains.

“The only way to know is to measure. Too many producers ignore nematode testing. They either think it is too expensive, time-consuming, and too much effort, or they do not believe they have a problem.”

She also points out that traditional maize-based rotational practices, such as maize on sunflower on maize, or maize on soya bean or dry beans, can lead to nematode build-up and may even exacerbate the problem.

“Field inspections remain important, but farmers must be aware that the problems usually go beyond the ‘hot spot’ areas. To confirm the species and prevalence, proper plant and soil analysis is needed.”

South Africa has several reliable nematode laboratories that offer diagnostic services. Locations include Potchefstroom, Cape Town, Pretoria, Nelspruit and Upington. Producers are advised to use one that is managed by nematologists who are registered with the South African Council for Natural Scientific Professions.

“The scientists and support staff at these laboratories have been trained properly and do the right tests, giving you peace of mind, that the results can be trusted,” says Fourie.

She acknowledges that the tests are expensive, but explains that the reason for the cost is because the analysis is done by trained staff using specialised equipment.

“But if the cost is compared with what farmers pay for fertiliser analysis and soil mapping, it makes sense to include testing for nematodes in the overall planning. At an additional fee, the same samples can also be used to determine the prevalence of the beneficial nematode population, which is an indicator of soil health.”

Fourie points out that although harmful nematodes are a major issue in sandy soils and for crops such as sunflower and soya bean, vegetables (specifically potatoes), as well as vineyards and deciduous fruit, serious nematode damage to crops in clay soils is also being picked up.

She notes that the impact of nematodes is underestimated because the non-specific above-ground symptoms are often confused with water stress or waterlogging, nutrient deficiencies, and secondary fungal or bacterial infections. The problem can easily be mistaken for something else, thus soil and plant analysis is necessary to identify the cause.

Since the situation is complex and often combined with secondary pathogenic infections, farmers must regularly inspect the roots of their crops for these soil-borne disease complexes. “In combination these can cause major crop losses,” warns Fourie.

How to do nematode sampling

Farmers who suspect nematode infestations should collect samples of the soil and crop. These samples, once analysed by a laboratory, can assist in future management decisions and actions. Consult your extension officer or agricultural adviser for suitable sampling methods, as these may differ among crops and localities.

Fourie says the golden rules to observe are:

• Take the samples six to eight weeks before harvesting, depending on the crop, when the crop is still active and the nematodes are feeding. “If you plan to harvest at the end of June, take samples at the end of April to the middle of May. Soil samples taken in a bare field are of little or no value in the battle against nematodes. The nematode population in the current season is a reliable indicator of what you can expect in the next season, which enables you to take the necessary precautions.”
• In the case of a missed opportunity, when a farmer was not able to take root samples before harvesting, they can still do a soil sample and submit that. “A post-harvest soil sample is not ideal and the results will not be as accurate as samples taken before harvesting, but at least one will still be able to get an idea. I would, however, caution farmers to remember to take proper samples during the next season.”

• Do not take samples after heavy rains. Not only is it difficult and messy to dig in a waterlogged field, but the results are not entirely reliable.
• Take samples of crop roots or other plant parts (tubers, pods, seeds) and soil. Endoparasites occur in the roots, while exoparasites live in the soil; both are necessary for a comprehensive picture of the rhizosphere.
• One sample is not enough to provide useful results given the variety of factors that influence nematode pressure. A simple guideline is to divide your field into four blocks or segments and take 10 samples each from a spot with unhealthy plants and 10 from a spot with healthy plants. A handful (200g to 300g) of soil and a substantial piece of root/other below plant parts are all that is needed. You can then combine the samples from the healthy and unhealthy areas taken in the same block into two of each category (healthy and unhealthy), leaving you with a total of four samples per block and 16 per field. This approach makes nematode testing more cost-effective. Place the combined samples in strong plastic bags and mark each one carefully and clearly, for example, Block A (unhealthy plants) and Block B (healthy plants) of Field A and the date. Immediately put the marked samples in insulated containers to keep them cool (not too cold or frozen) and out of the sun. Handle the samples with care, as certain nematode groups are easily damaged during handling. It is important to deliver the samples to your nearest laboratory as soon as possible – the fresher the better, and no longer than two days after sampling.

Nematode management

According to Fourie, there are a number of management practices that can be combined to limit the damage of nematodes. These include:

• Cultural practices such as ploughing (although controversial in terms of its efficacy to lower plant-parasitic nematode densities in soil), fallowing, and weed control. Turning the soil by means of ploughing allows for killing a part of the nematode population that is present in the top soil by the heat of the sun during warm summer seasons.
  A field should also be clean of weeds to prevent infestation, as nematodes can survive in their roots. “Live root-knot nematode females have been found in the middle of winter in the Free State in roots of ragwort bushes (commonly referred to as John Deere bossies). These abundant, yellow-flowered weeds create the ideal habitat for the nematodes, which start to reproduce as soon as the soil temperature rises.”
• Crop rotation is encouraged, but it is important to use poor nematode host or non-host cultivars. Using cover crops can help reduce the density of plant-parasitic nematodes, but it may also increase the density of beneficial nematodes.
• Chemical crop-protection practices such as the use of nematicide and fungicide seed treatments. Chemical nematicides are highly effective in reducing nematode pest densities over the short term.
• Biological management solutions can be employed and are increasingly used to combat nematode problems. These include soil micro-organisms, such as bacteria, algae, fungi and protozoa, that interact with the surrounding environment and keep the ecosystem healthy. Seed treatments are the first line of defence against harmful nematodes once a crop seed is placed into the soil, as they help defend and boost yield potential by protecting against early-stage diseases, insect pests, and plant-parasitic nematodes. In addition, fumigant and non-fumigant crop-protection products can be used when the nematode pressure is high.

“The decision to apply a nematicide should be based on the need to reduce nematode populations to below economically damaging population densities,” says Fourie. Seed treatments are generally safe when used according to label instructions, providing early-season disease and pest control and helping seeds get off to a healthy start.

“Seed treatments enhance seed germination, ensuring a healthy start for the crop. By providing an initial defence, treatments reduce the need for more aggressive field-level pest control measures,” Yolandi Furniss, marketing lead at Syngenta Seedcare, points out.

Agriculture is increasingly focusing on developing more eco-friendly treatments to make them safer and more targeted: “The industry is also focusing on the growth of biological treatments, which offer a more sustainable alternative,” she adds.

Furniss says Syngenta’s Avicata offers triple protection against nematodes, early-season insects and disease while helping to protect the investment and value of traits and genetics during the plant’s most vulnerable stage.

Stefan van Zyl, business manager for Syngenta Seedcare in South Africa, cautions that there is no silver bullet: nematode management starts with knowledge, which includes ways to understand the severity, cause and scope of the problem.

Finally, he says integrated pest management is required, including in-furrow and seed treatments, using nematode-resistant cultivars, protection against secondary infections, weed control and crop rotation.

Email Dr Driekie Fourie at [email protected].