With the onset of summer weather, pests – cruciferous shiner and cruciferous stem weevils – spread rapidly in winter rapeseed crops, the State Plant Protection Service (VAAD) informed.
The representatives of the service indicate that the spread of the cruciferous moth has reached 100% in some volumes in Zemgale, and two to seven pests can be found on one plant.
The representatives of VAAD explain that the cruciferous moth has spread the most in the fields in Zemgale and Kurzeme, where 60-100% spread has been observed, and on average four to nine pests are found on one plant, while in Latgale the spread of the pest is 14% with an average of one to three pests on one plant.
Representatives of the service note that cruciferous shiners eat the pollen, stamens and petals of the inner part of the flower, while the larvae feed on the pollen. Also, the beetles eat the pollen, stamens, petals, and the larvae feed on the pollen. As a result of damage, the flowers wither, fall and the number of discarded pods decreases.
VAAD representatives emphasize that winter rapeseed fields should be regularly inspected in summer and in favorable weather conditions for the development of pests, and a decision should be made to take plant protection measures if one to four individuals have grown on one plant.
Also, cruciferous stem weevils continue to spread in all regions of Latvia, the prevalence of which has reached 32% in some fields. Service representatives indicate that even two to five adult pests can be observed on one plant.
On the other hand, the chief agronomist of Lauksaimnieku cooperative “Latraps” Ęirts Ozols states that there is no increased risk of pests for rapeseed fields. He notes that the spread of pests is affected by rapid changes in the weather. As the weather rapidly becomes warmer, insects also become more active, however, owners know what to do in such situations and how to successfully deal with pests.
Ozols mentions that currently the weather is favorable for the use of plant protection products, but it is necessary to act immediately and regularly monitor the fields. He points out that in general, growing canola tends to be challenging for farmers because crops are very sensitive to weather.
VAAD is a state direct administration institution established in 1998, the purpose of which is to ensure the sustainable use, protection and circulation of crop and forest resources in order to preserve their biological diversity, promote public safety and protect the surrounding environment from possible pollution caused by plant protection and fertilizers, to create prerequisites for farmers to have access to healthy and high-quality propagating material, as well as to increase productivity and agricultural competitiveness.
Canola field. Photo: Zane Bitere/LETA
