会议专题

Pests and their natural enemies within organic winter oilseed rape (Brassica napus L.).

The 92 % of 250,000 ha of organically cultivated land in the Czech Republic consists of pastures and permanent grass cultures. The part of arable land is only 8 % and oilseed crops there practically absent. To the contrary, growing areas of conventionally produced winter oilseed rape has fluctuated at about 300,000 ha in recent years (10-12 % of total arable land in the CR). Problems with growing oilseed rape in organic agriculture are predominantly related to the spread of weeds, pests and diseases under the influence of prevailing conventional technology. This study aims to specify optimal methods of growth development and weeds reduction by oilseed rape within organic production technology. Also, the occurrence of natural enemies (Hymenoptera) was monitored to determine their importance for oilseed rape pest reduction. The small-plot trials (10 m2) with the officially certified field for organic production. The occurrence of pests and parasitoids was monitored weekly during end of April till end of June on a weekly basis, using a 250 mm sweep net. The numbers of pest larvae and level of their parasitization were monitored weekly during half of May till half of July on a weekly basis, using water traps. The yield characteristics were also assessed. Compared were organically grown plots and those with conventional crop protection.The results confirmed the capacity of successful OOR growing, using wide rows and a higher sowing density. Under optimal conditions, the total yield potential of OOR could achieve 60-70 % of yields commonly reached by conventional technology. Numerous oilseed rape pest parasitoids were found during flowering: namely Tersilochus and Phradis (Ichneumonidae)-parasitoids of pollen beetles (Meligethes spp.); Trichomalus and Mesopolobus (Pteromalidae)-parasitoids of cabbage seed weevil (Ceutorhynchus assimilis); Platygaster (Platygastridae)-parasitoids of brassica pod midge (Dasineura brassicae). The difference in occurence of parasitoids, pests and level of their larval parasitization was found between organically grown plots and those with conventional chemical crop protection. The consequences for integrated oilseed rape pest management are discussed.

organic oilseed rape growing technology pests parasitoids Hymenoptera Meligethes aeneus Ceutorhynchus assimilis

Daniel Nerad Josef (S)ke(r)ík Petr Baranyk Perla Kuchtova Jan Kazda

Union of Oilseeds Growers and Processors (SPZO), Jankovcova 18, 170 37 Prague, Czech Republic Department of Crop Protection, Czech University of Agriculture, Prague (CUAP), 165 21 Czech Republic Department of Crop Production, Czech University of Agriculture, Prague (CUAP), 165 21 Czech Republic

国际会议

第十二届国际油菜大会( The 12th International Rapeseed Congress)

武汉

英文

1520-1522

2007-03-26(万方平台首次上网日期,不代表论文的发表时间)