The arrival of new shoots in orange groves, which takes place in the second half of the year, marks a critical period for citrus growers in the citrus belt. This phase, which runs from July to October, accounts for between 50 % and 80 % of annual shoots, depending on the region. The process intensifies with the onset of rainfall, requiring stricter control of the psyllid — an insect that feeds on the shoots and transmits the bacterium that causes citrus greening. Data from the Alerta Psilídeo platform show a 55 % increase in the number of shoots in the second half of July compared with the first half.

This stage of plant development is particularly delicate, as new shoots are highly vulnerable to psyllid attack. Fundecitrus researcher Juan Camilo Cifuentes Arenas highlights the importance of strengthening phytosanitary measures, especially spraying, until the leaves are more developed and less susceptible.

“These shoots are the most favorable for the psyllid to feed on and, above all, to transmit the greening bacterium. That is why more than 50 % of psyllid captures occur during this period. The greater the budding, the more food is available — and the higher the incidence of the insect,” explains Arenas.

According to the platform, psyllid captures in traps increased by 10 % in the second half of July compared with the previous fortnight.

Diseased Plants: More budding, greater risk

The researcher also draws attention to the different behavior of infected plants.

“Because of greening, they tend to sprout in much greater numbers and up to two months earlier than healthy plants, which increases the chances of infection and the spread of the disease. This is why the moment calls for constant vigilance from growers and stricter management strategies,” Arenas stresses.

Scource: Fundecitrus

New stage of action wants to mobilize adults and children in urban areas to help fight the disease.

The Brazilian Citriculture Defense Fund is working hard to promote the campaign United Against Greening. Now, the campaign extends to the citrus belt urban areas, areas where, at first, there is no management of the disease. The new stage of the work wants to mobilize the population of these areas, and in rural areas as well, where there are no commercial groves, as it’s the case of small farms and ranches.

In order to do that, Fundecitrus has hired a new team, which is developing actions in these places. One of them is the replacement of orange and lemon trees with other fruit varieties. The teams have visited homes and schools as well, to talk about the campaign. The actions to exchange the plants are carried out through home visits, and have the support of lectures for students and teachers of municipal schools, production of printed materials and cars with sound system to bring information to the community. So far more than 2,000 plants have been exchanged. “Citrus and myrtle plants in towns make it difficult to fight citrus greening on commercial properties. Developing this work in areas with no management is extremely important due to the destructive potential of the disease, “says Fundecitrus agronomist, Mr. Ivaldo Sala, work coordinator.

The teams work in partnership with town halls and companies to exchange myrtles, and orange, lemon and mandarin trees contaminated with citrus greening, which hasn’t received the chemical control recommended, for other fruit and ornamental trees. The psyllid, citrus greening transmitting insect, when feeding on orange, lemon and mandarin trees infected with the disease, it acquires the bacterium and starts to spread it. The insect travels long distances, leaves the urban area and arrives in the rural area, contaminating the groves.