Effect of allelopathic seed meals on the weed infestation and yielding of maize

Seed-meals of allelopathic crops may serve as an effective and environmentally friendly alternative for weed control. In this experiment, two series of a pot and one-year of micro-plot field research were conducted in southern Poland, to determine the phytotoxic impact of different seed-meals on indigenous weeds and maize (Zea mays L.) establishment. The pot experiment was performed for four meals: seed-meals of Sinapis alba L., Brassica napus L. and Fagopyrum esculentum Moench and a meal of Raphanus raphanistrum L. plants in the fruiting stage, at doses of meals 2 and 4% (w/w). As a result, the seed-meals of S. alba and F. esculentum were proved to be the most effective against the growth of tested weeds: Echinochloa crus-galli and Amaranthus retroflexus and chosen for the field experiment. In the field, the seed meals were applied into the sandy soil by the end of April 2015 at two doses, equal to 1 and 2% (w/w) per 15-cm of soil and mixed with soil by cultivator. On the same day maize cv. Wilga was sown. Weed composition was assessed at the beginning of July, and weed biomass was measured by the end of August, at the harvest time. Both doses of S. alba seed-meals and a higher dose of F. esculentum seed-meal totally eliminated Echinochloa crus-galli (L.) P.Beauv. and Erodium cicutarium (L.) L`Her. from the plots. At the same time, the number of maize plants and their vegetative biomass was significantly inhibited, as compared to the herbicide control. Interestingly, the application of seed meals stimulated the growth of maize cobs and, as a result, the yield of maize kernels from the plots treated with the seed-meals was similar to the herbicide control. Further research should address different terms and doses of seed-meals applications in the maize cultivation.