Efficacy of organic products against insect pests in alfalfa grown for seeds

Abstract

0BOrganic pesticides can be excellent alternatives to chemical pesticides. They occupy an important place in the plant protection sector. Evaluation of the efficacy was conducted using an alginate from seaweed (organic insecticide) and two organic fertilizers (highly concentrated complex organic fertilizer and natural CO₂ fertilizer), used alone and in combinations to control major pests in alfalfa seed production such as alfalfa seed chalcid Bruchophagus roddi Guss., alfalfa plant bug, Adelphocoris lineolatus Goeze and pea aphid, Acyrthosiphon pisum Harr. We conducted field trials during three growing seasons. Treatments were carried out at the beginning of the flowering stage in second regrowth. The seaweed alginate had high efficacy and excellent control on the three insect species density one week after treatment (over 80%), while the complex organic fertilizer exhibited insecticidal action against pests and its effect exceeded 60% seventy days after treatment and provided a medium level of control. The mix of the two organic products provided the highest efficacy and long-lasting effects on the three insect species and additive effects were observed. The combination realized the highest seed yield and an increase by 29.7%. Treatment with organic products is suitable for organic farming.