Including more than three crops in a cash crop system may not only help increase yield, but significantly enhance the long-term sustainability of a farm. Dr Johann Strauss of the Western Cape Department of Agriculture spoke to Glenneis Kriel about the benefits of crop diversity.
Around the world, a growing number of farmers are switching to crop rotation due to its capacity to improve farm earnings through higher yield and reduced fertiliser, pesticide and herbicide usage, while boosting sustainability.
Long-term rotation trials by the Western Cape Department of Agriculture at the Langgewens Research Farm in the Swartland and Tygerhoek in the Southern Cape confirm this.
In crop rotation evaluations that started at Langgewens in 1996, wheat monoculture has always been the poorest performer of all the combinations under trial. But in rotations that included at least one type of legume, such as lupines or medics, the average wheat yield was 30% higher than when wheat was produced in a monoculture. The yields of rotations containing no legumes were on average 12% higher.
BEST ROTATION
A medic-canola-medic- wheat rotation consistently performed the best, producing an average yield 37% better than a system where wheat was produced on its own (see table).
Water- and nitrogen-use efficiency also improved. Wateruse efficiency of rotations that included canola was 11% higher, and rotations that included one or more years of legume crops or pastures were between 26% and 31,6% higher than when wheat was planted on its own.
Nitrogen-use efficiency was on average 89% better in rotations that included legumes than when wheat was produced alone, and 35% better when the rotation included only one year of legumes. The use of canola in the rotation, without any legumes, increased nitrogen-use efficiency by 9%.
During the past two seasons, of which 2017 was dry and 2018 had below-average rainfall, the researchers set out to establish how low the nitrogen level could be reduced in a medic and wheat rotation.
Denne historien er fra August 9, 2019-utgaven av Farmer's Weekly.
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Denne historien er fra August 9, 2019-utgaven av Farmer's Weekly.
Start din 7-dagers gratis prøveperiode på Magzter GOLD for å få tilgang til tusenvis av utvalgte premiumhistorier og 9000+ magasiner og aviser.
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Understanding eye conditions in horses: causes and first aid
A horse can get a swollen eye from bumping it against a tree, shaking its head to keep flies away, or even snake venom
IPM requires a completely different mindset
You need to investigate any beneficial insects that may appear on your plants, or you can purchase them
Does parrot farming protect wild species?
Those in favour of commercial captive breeding argue that breeding parrots to sell can relieve pressure on wild populations. Researchers Neil D'Cruze and Rowan Martin review the evidence.
Bacterial and fungal diseases of garlic
Garlic can be prone to bacterial and fungal diseases, and it's important that farmers are proactive in preventing infection and practise appropriate management. Magda du Toit reports.
Responsible wastewater management: a crucial part of farming
The inadequate management of waste water is a challenge that the agriculture sector needs to deal with. Magda du Toit spoke to experts in waste and water management about a cost-effective treatment system.
Technology that can help protect South Africa's farms
Farm attacks, murders, livestock and crop theft, and other rural crimes are a growing concern in South Africa. As a result, more and more farmers are turning to advanced security technology to protect their lives, properties, and livelihoods. Sinenhlanhla Mncwango spoke to experts about the security strategies that producers can adopt to combat these threats.
The impact of theft on farms in South Africa
A high number of livestock are being stolen every year in South Africa. Insurance is expensive and farmers are battling to find solutions to the problem, says Dr Lindie von Maltitz, agricultural economics lecturer in the Faculty of Natural and Agricultural Sciences at the University of the Free State.
Staying afloat amid the cost-price squeeze
John Hudson, head of agriculture at Nedbank Commercial Banking, spoke to Glenneis Kriel about the importance of environmental and social sustainability for a prosperous agriculture sector.
Free State has no reason to mark Transport Month
Free State Agriculture (FSA) is very concerned about the extremely poor state of rural paved and gravel roads in the province and has very little, if anything, to celebrate during Transport Month, which takes place every October.
SA's food system ‘vulnerable to climate change'
The Just Transition Agenda for Food System Policymaking in SA webinar, hosted by the Institute for Economic Justice (IEJ) in October, highlighted the role that South Africa’s food system plays in contributing to climate change and how vulnerable it is to the impact thereof.
