On the domestic market, prices for South African oranges are 20 to 30% lower than usual, selling for an average of R2.50 and R3 per kilogram.
“It’s a mess,” declares a municipal market citrus trader who doesn’t want to be named. “We’ve never had a citrus season like this, I’d say it’s one of the most difficult years we’ve ever had.”
Current evidence in citrus indicates that gibberellins (GAs) are main determinants of early fruit set while subsequent growth of developing fruits is mostly dependent upon carbohydrate availability. In this work, branch girdling performed at anthesis in Satsuma mandarin (Citrus unshiu (Mak.) Marc.) cv. Okitsu transitorily reduced early abscission rates (12–32 days after anthesis, DAA) delaying initially the process of natural fruitlet drop. The effects of girdling on growth, gibberellin (GA) and carbohydrate concentrations in developing ovaries and fruitlets were assessed during this initial growth stage (0–69 DAA). In girdled branches, abscission rate reduction was preceded by elevated concentrations of carbohydrate and GA in developing ovaries and fruitlets.
CGA’s Justin Chadwick said cold treatment requirement is unnecessary, unjustified and disproportionate.
The South African citrus industry is scrambling to avert disruptions in its citrus exports to the European Union due to changes in regulations governing the importation of oranges into the EU.
The new regulations, which deal specifically with orange imports from South Africa and other sub-Saharan countries, were published in the Official Journal of the European Union on Tuesday and will come into force today.
Running a fruit exporting company feels a bit like being an operational company that happens to sell fruit at the moment, an exporter remarks, when managing logistics and fighting for space and equipment on vessels take up most of their days.
“You have to be passionate about fruit to be working in the fruit trade,” he says. “It’s not an easy place at the moment.”
Slow colour development on Valencias in Limpopo Province has meant at least two to three weeks of lost marketing opportunities, which, along with impediments to South Africa’s lemon and the grapefruit harvest, could explain why citrus volumes via Durban port have, thus far, not been as high as expected.
This paper describes the physiological effects of abscisic acid (ABA) and 100 mM NaCl on citrus plants. Water potential, leaf abscission, ethylene production, photosynthetic rate, stomatal conductance, and chloride accumulation in roots and leaves were measured in plants of Salustiana scion [Citrus sinensis (L) Osbeck] grafted onto Carrizo citrange (Citrus sinensis [L.] Osbeck · Poncirus trifoliata [L.] Raf) rootstock. Plants under salt stress accumulated high amounts of chloride, increased ethylene production, and induced leaf abscission. Stomatal conductance and photosynthetic rates rapidly dropped after salinization.
Although sulphur is one of the essential nutrients for plant growth with a crop requirement similar to phosphorus (P), this nutrient element has received little attention because it is supplied in insecticides, fungicides, manure and from the atmosphere. With the relaxation of this requirement, and restrictions on sulphur dioxide emissions by industries it has become apparent that sulphur deficiency is widespread throughout the world. The majority of farmers submitting samples for soil and leaf nutrient analysis do not request a sulphur (S) test. This is due to the fact that farmers are still under the impression that there is enough sulphur in the soil.
Foliar fertilization efficiently meets the nutrient demand of tree fruit crops during periods when soil conditions (low or high temperatures, low or excess soil moisture, pH, salinity) render soil-applied fertilizers ineffective, when nutrients (e.g., phosphate, potassium, and trace elements) become fixed in the soil, and when tree nutrient demand is high. Applying nutrients directly to leaves ensures that the metabolic machinery of the tree is not compromised by low availability of an essential nutrient. It should be noted that phloem mobile nutrients applied to the foliage are translocated to all tree parts, even feeder roots.
This week, the European Union’s (EU) Standing Committee on Plant, Animal, Food and Feed (SCOPAFF) will discuss and, possibly vote on, new and arguably misinformed regulations on False Coddling Moth (FCM) which pose a major threat to Southern African orange exports.