Growth, weed control, and nitrogen uptake of winter-killed cover crops, and their effects on maize in conservation agriculture

The utilization of winter-killed cover crops is increasing due to their benefits in intensive cropping systems based on summer cash crops. However, there still a lack knowledge about management temperate climates, where maize planted early under conservation tillage techniques. For these conditions, here we document for the first time various agronomic effects different options. We evaluated production, nitrogen uptake, and weed control five pure crop species, as well production subsequent its recovery, four sites. Several options were compared (cover fertilization, sowing technique, termination method). Legume (Trifolium alexandrinum L. Vicia benghalensis L.) had small above-ground biomass (on average 0.6 t DM ha−1 November), while non-legumes (Avena strigosa Schreb., Sinapis alba L., Raphanus sativus 2.4 ha−1, N uptake 89 kg ha−1) was higher, uptake. difference between two groups smaller at end winter (0.4 Mg ha−1), when out eight site × year combinations, soil mineral significantly higher treatment no crop, presumably release from Cover did not increase residues hamper emergence. recovery by 86% legumes − 1% non-legumes. conclude that productivity, (especially non-legume species) are encouraging, with negative yield.