Root rot, caused by Phytophthora cinnamomi, is the most serious and important disease of avocados worldwide. P. cinnamomi has more than 1 000 hosts, including many species of annual flower crops, berries, deciduous fruit trees, ornamentals, and vegetables. Locally, it’s found in all production areas, as well as home gardens. The severity of infection varies, but the potential loss is very big if no control measures are taken.
Root rot
Root rot likes soil moisture and poor drainage. Trees of any size and age may be affected. “The pathogen is easily spread through movement of contaminated nursery stock […] on equipment and shoes, in seed from fruit lying on infested soil, or by any activity by people or animals that moves moist soil from one place to another,” says the Division of Agriculture and Natural Resources, University of California.
Phytophthora produces four different spore stages that are involved in disease development and survival: sporangia, zoospores, chlamydospores, and oospores. They spread rapidly in water, moving over or through the soil. Entire areas can become infested. Phytophthora species are not true fungi but have many fungal-like attributes.
Where Phytophthora is present, leaves are smaller, paler in colour, turn yellow, wilt, and then drop off, and the entire tree assumes a bare appearance.
This story is from the {{IssueName}} edition of {{MagazineName}}.
Start your 7-day Magzter GOLD free trial to access thousands of curated premium stories, and 9,000+ magazines and newspapers.
Already a subscriber ? Sign In
This story is from the {{IssueName}} edition of {{MagazineName}}.
Start your 7-day Magzter GOLD free trial to access thousands of curated premium stories, and 9,000+ magazines and newspapers.
Already a subscriber? Sign In
Review: the Toyota Hilux 2.8GD-6 DC 4×4 GR-Sport III
The third iteration of the Hilux GR-Sport has finally achieved a sense of presence and style befitting its raceinspired branding. But is this the ultimate modern Hilux? Car Magazine takes a closer look.
Why maize prices soar in Kenya and Malawi but not Tanzania
Namhla Landani, an economist at the Centre for Competition, Regulation and Economic Development, University of Johannesburg, and Arthur Khomotso Mahuma, economist and researcher at the Centre for Competition, Regulation and Economic Development, University of Johannesburg, analyse the issue.
Wet carcass syndrome: a scourge in SA sheep farming
Wet carcass syndrome continues to take a huge financial toll on South African sheep farmers. Octavia Avesca Spandiel spoke to two experts about the ongoing genetic research aimed at addressing this issue.
Pollination innovation
Bee-Tech Group is transforming South African agriculture with pollination technologies that boost crop yields and enhance sustainability. Founder Michiel Bruggeman spoke to Octavia Avesca Spandiel.
The valuable addition that makes this farm tick
Owning the value chain provides farmers with far more control over their produce. However, it requires a fine balance between production and ensuring there is a strong and steady market. Lindi Botha visited Rosemary Hill to find out how this essential oil producer leverages hospitality to make the farm viable.
The benefits of recirculating aquaculture systems
A powerful set of attributes has established recirculating aquaculture systems as a cornerstone of global temperate fish farming, writes Leslie Ter Morshuizen, owner of Aquaculture Solutions.
Minister has big plans for emerging and commercial farmers
DA leader and Minister of Agriculture John Steenhuisen spoke to Glenneis Kriel about his priorities for his department over the next five years, including an increased focus on biosecurity.
New study aims to make wheat more disease resistant
A recent international study explains how bread wheat has helped to transform the ancient world on its path to becoming the iconic crop that today helps sustain a global population of eight billion.
Conservation farming and biodiversity boost soil health and sustainability
A recent academic event focused on research into the links between soil biodiversity, soil health and sustainable agriculture
What has led to the unparalleled rice shortage in Japan?
Japan is facing a rice shortage amid concerns about a potential 'megaquake', several typhoons and an annual week-long holiday, which has led to an increase in panic buying.