We’ve selected a few of the latest new geographic, host and species records for plant pests and diseases from CAB Abstracts. Records this fortnight include the first report of Melon necrotic spot virus in Brazil, the first report of chrysanthemum stem blight and dieback (caused by Tomato spotted wilt virus) in China and the first report of Tomato leaf curl New Delhi virus infecting zucchini/courgette in Morocco.
We’ve selected a few of the latest new geographic, host and species records for plant pests and diseases from CAB Abstracts. Records this fortnight include the first report of plum pox virus (PPV) in Japan, the first report of white blister rust disease caused by Albugo occidentalis on spinach in Turkey and the first report of orange rust on sugarcane caused by Puccinia kuehnii in Guyana.
“No matter where you’re from, your dreams are valid!” Passionate words spoken in 2014 during an indelible Oscar moment. The utterance of these words, coupled with the winning of an Academy Award, announced Lupita Nyong’o’s entry into the global stage. Two years later in Lupita’s country of origin, Kenya, long-held dreams in the plant health sector are realized.
Indeed, the journey to realizing the usefulness of mobile technologies for the plant health sector has been long, and to some extent treacherous. Was the Plantwise program setting up the agricultural extension officers for failure? Was the program having unrealistic expectations? Could it be, in the program’s quest to keep up with the times, it was essentially building an ivory tower? All these were questions Plantwise grappled with in 2014 when it introduced mobile technologies for the running of plant clinics.
In the first half of 2013 two million red palm weevils were removed from farms in Abu Dhabi using pheromone traps. The large number of red palm weevils in the area prompted the launch of the initiative, which forms part of the Abu Dhabi Farmers’ Services Centre’s (ADFSC) Integrated Pest Management project. The project was implemented in coordination with the Abu Dhabi Food Control Authority (ADFCA) and will run throughout the rest of 2013 and 2014. This project aims to control palm tree pests while minimising pesticide usage, by increasing the knowledge and capabilities of workers to enable them to implement the best control methods for pests.
BBSRC (Biotechnology and Biological Sciences Research Council) and Syngenta funded scientists at the University of York and University of Durham have discovered a gene called AmGSTF1 that plays a key role in controlling multiple herbicide resistance in black-grass (Alopecurus myosuroides) and annual rye-grass (Lolium rigidum). Now the gene that confers resistance has been identified, it is hoped that chemicals that inhibit the gene may be able to be used in future to make herbicides effective against resistant weeds.
Black-grass and rye-grass are widespread weeds which cause problems in cereal and oilseed rape farming. Management using herbicides is becoming increasingly difficult since both black-grass and rye-grass can acquire a single defence mechanism that confers resistance to multiple herbicides- known as multiple herbicide resistance. The genetics of multiple herbicide resistance have been poorly understood until recently, however scientists have now discovered that a gene producing an enzyme called glutathione transferase (GST) is responsible for multiple herbicide resistance. Scientists created transgenic thale cress (Arabidopsis thaliana) plants with the GST producing gene inserted which were resistant. GSTs are known to detoxify herbicides, but project leader Professor Rob Edwards of the Centre for Novel Agricultural Products at the University of York believes that the gene they discovered works as a kind of ‘master switch’ that activates a range of protective mechanisms in the plant. When resistant plants with the GST gene are sprayed with GST inhibiting chemicals, they become susceptible to herbicides. This demonstrates the potential for using GST inhibiting compounds in future herbicide formulations to manage resistant rye-grass and black-grass. These weeds are currently very difficult to manage due to their widespread herbicide resistance.
Vegetable farmers in the Kayunga and Mukono districts of Uganda are reporting crop losses due to black rot disease. One farmer, Twaha Kahooza of Kyampisi village, Kayunga Sub-county, says he had planted four acres of cabbages and was expecting about Shs18m (about £4,500 or US$7,000) from the harvest, however he only managed to get Shs5m (about £1,200 or US$2,000).
Black rot is caused by the bacterium Xanthomonas campestris pv. campestris and is one of the most destructive diseases of cabbage and other crucifers such as broccoli, brussels sprouts, Chinese cabbage, collards, kohlrabi and mustard. The disease is usually most prevalent in low lying areas where plants remain wet for long periods. The disease is characterized by a yellow V-shaped lesion at the leaf margin which turns brown as the leaf area expands. The disease can also affect seedlings and can enter the plant through insect feeding or injury to the plant. Management of black rot in crucifers includes obtaining certified, pathogen free seed, ensuring there is enough space between plants and crop rotation.To read more about black rot and black rot management visit factsheets on the Plantwise Knowledge Bank.
To read a Plantwise Factsheet for Farmers written in Uganda click here.
To find out more about Plantwise plant clinics running in Uganda, click here
Maize Lethal Necrosis disease, which was first reported in Kenya and Tanzania, has now spread to Uganda, raising concerns for food security in the country. The Ministry of Agriculture has warned that Maize Lethal Necrosis has been reported in districts in eastern Uganda, including Busia and Tororo.
A spokesman for the Agriculture Research Organisation, Robert Anguzo, has said that Ugandan scientists are working in collaboration with the International Maize and Wheat Improvement Centre (CIMMYT) to find management solutions to the disease.
More information about the pests and viruses associated with Maize Lethal Necrosis and the management of the disease can be found on the Plantwise Knowledge Bank