La campagne 2002 aura été plutôt bonne pour le tournesol malgré une pression assez forte des maladies, à commencer par un retour remarqué du phomopsis en Midi-Pyrénées et dans l'Aude.
Les autres maladies telles que sclérotinia, phoma, etc., sont assez présentes. Le mildiou semble en revanche absent? mais l'inoculum reste là et le contournement par ce parasite des résistances variétales du tournesol reste possible. La surveillance continue et la vigilance reste de mise.
Il est rappelé l'intérêt de mesures prophylactiques (ou mesures indirectes) contre le mildiou et le phomopsis.
Le désherbage de prélevée a connu quelques difficultés, et certaines adventices continuent à s'étendre (notamment l'ambroisie et la lampourde). Côté ravageurs, c'est calme (on note quelques crispations de pucerons et on signale la noctuelle Autographa gamma). The 2002 season was generally good for sunflower, despite the pressure exerted by a number of diseases, beginning with the noteworthy return of phomopsis in the Midi-Pyrenees and Aude regions.
The other common diseases such as sclerotinia, phoma, etc. showed their faces as usual. Downy mildew on the other hand was a notable absentee? the inoculum is still there however, and the avoidance by this parasite of the varietal resistance of sunflower remains a possibility. Surveillance continues and vigilance is the order of the day.
The article goes on to provide a reminder of the usefulness of preventive (or indirect) measures against downy mildew and phomopsis.
Pre-emergence weed control met with several difficulties, and certain weeds continue to spread, especially ragweed and rough cocklebur. It was a generally calm season as far as pests are concerned, with just a few reports of aphids and isolated populations of common silver Y moth.
