[:en]Today, we are all aware of the symptoms produced by the New Delhi virus in cucurbits, and how it has evolved over the last year... We are facing the imminent start of the melon harvest, and reviewing the tests we did at IDEAGRO last season, we found melons that showed damage like the ones that can be seen in the image below.
This is an incident detected at the beginning of September 2013, in melons that had been harvested in perfect condition and kept in cold rooms for 10 days. At the time, at IDEAGRO we carry out all kinds of tests (nutritional analysis, laboratory isolation, microscope observations, bibliographic reviews, etc...) and we consult with technical specialists in melon cultivation as well as with specialists in "post-harvest" from the Polytechnic University of Cartagena without being able to reach a clear conclusion about the causes of the observed physiopathy.
Today, We dare to affirm that the damage observed in "post-harvest" melons were possibly the effects of the so-called New Delhi virus. The symptoms identified were the following:
- Superficial spots on the skin that did not affect the inner skin (similar to melon pox but in shades of dark brown instead of white).
- Pulp dehydration.
- Desiccation of vascular vessels and appearance of interior fungal contamination of various kinds.
- With the passage of time, strong dehydration of the fruit and deformation.
What is worrisome is that these damages were NOT evident at the time of collection, they were observed after 8-10 days of storage, therefore, in this campaign that is beginning, it will be key to observe this kind of physiopathies, and see if they are they repeat.
Current situation
Efforts to protect crops by physical means, through biological control or through the use of resistance inducers have been enormous, practically all farmers chose to shield their greenhouses against what could happen, however, although the incidence has been low, the consequences could be fatal. With the arrival of heat, it is most likely that the virus will activate and increase, but we do not know in what percentage it will activate.
In the growing plant, what we have observed to date are: darker green veins, curling leaves and a tendency to yellow at the apex. In addition, collapse occurs, and the plant stops growing, therefore the fruit does not develop or remains corked.
What threat does ToLCNDV represent for Spanish agriculture?
The introduction of this virus in Spain has been very bad news. From an epidemiological point of view, it is expected that it behaves as our well-known spoon virus behaved, except that the host range described for this virus is broader. The fact that it potentially affects very diverse crops can cause a continuous source of inoculum to exist in the field, with which the spread of the disease will only be limited by the presence or absence of whitefly. It remains to be seen whether the strain introduced in Spain is specific to cucurbits and does not spread to other crops.
And from IDEAGRO, what do we think?
During the last months, at IDEAGRO we have carried out more than 12 tests on different crops, and we are currently working on zucchini and melon; so far with good results
Our cultural practices are:
- Intensify physical barriers and control over Bemisia tabaci (following the indications of the different organizations and experts in the field).
- Eliminate stress situations in the plant.
- Plantation well nourished and "strong"; strong root and vegetative development of the plant.
- Use of resistance inducers periodically throughout the crop cycle (in our case, we work with Procrop ISR from the American company Alltech Crop Science with good results)
We all know that For now, there is no product to control the "virus", but we have observed that the use of inducers can reduce the "subclinical" disease of the plant, which develops in a more vigorous and healthy way and, when in some cases it has been affected by the virus, it has been observed that it has remained localized in the part of the plant that has been infected, slowing down the infection of the rest of the plant.
For more info, contact us:
Phone: 968118086
E-mail: info@ideagro.es
www.ideagro.es
@IDEAGRO & @palazonpedro
> The New Delhi Virus.
New Delhi tomato yellow curl virus (Tomato leaf curl New Delhi virus, ToLCNDV) It was first described in 1995 as a Tomato yellow leaf curl virus complex variant affecting tomato crops in India. Subsequently, the international committee on virus taxonomy recognized it as an independent viral species. It is a virus of the Geminiviridae family and the Begomovirus genus., initially geographically confined to the Indian subcontinent, but has been expanding to other parts of Asia, including China and the Middle East. Today we know that it has also arrived in Spain. ToLCNDV is transmitted by whitefly (Bemisia tabaci Genn.).
It must be taken into account that the New Delhi virus is not a harmful quarantine organism in Community legislation, It is not included in any EPPO list and therefore is not considered a pest of special relevance. The first detection of ToLCNDV in Spain was made on courgette plants grown in Campo de Cartagena (Murcia) and Almería.
Sources:
http://www.ingenierojsh.com/2014/02/efectos-del-virus-de-nueva-delhi-en.html
http://elhocino-adra.blogspot.com.es/2013/08/tomato-leaf-curl-new-delhi-virus-en-el.html[:]
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