| In this experiment, we use the dried and crushed rice straw as a donor, and the Chenopodium glaucun and Brassica napus are the receptors, using the covering and mixed soil methods to study the allelopathic effects of rice straw powder on Chenopodium glaucum and Brassica napus seedlings. The purpose is to find out a method of using waste rice straw to control the fields Chenopodium glaucum, and provide the basis for the biological control of weeds in rape field.Results of pot experiment show that: using the same quality of rice straw powder, the inhibition for Chenopodum glaucum is far greater than the inhibition for Brassica napus, when rice straw powder dosage of 10 g / pot(about 10 / 150cm2), the inhibition rate of Chenopodium glaucum seed germination is over 85%, while the inhibition rate of Brassica napus seed germination is only 17%. The results also show that increasing the amount of rice straw powder, differences between the repeats in sameg roup treated weak down. Indicating that the greater the amount of rice straw powder used, inhibitory effect on seed germination of Chenopodium glaucum is stronger and more stable. This results for support rice straw powder applied to control Chenopodium glaucum in rape field provide a good basis for selection.The experiment also compared two different application methods of the rice straw powder for inspecting the effect on seed germination of Chenopodium glaucum, the results showed that: the use of rice straw powder covered and with dry soil mixed use in Chenopodium glaucum inhibition was not significant; but rice straw powder coverage of germinated seedlings of Chenopodium glaucum has some suppression of the killing effect, and mix the soil applied to the role of C. glaucum seedlings germinated unlikely.Sufficient water is the key factor to ensure the inhibition effects of rice straw powder. The right amount of water can leach the allelochemicals in rice straw powder out fully, and thus to play a role in suppressing weeds. When Chenopodium quinoa seed just germinated, high concentrations of allelochemicals also inhibited and killed their seedlings, but little affected when Chenopodium glaucum seedlings grow to 2 true leaves. So, in practice, taking into account the field water holding effect, it is recommended that rice straw powder used for mixing soil treatment when the weed seeds has not been germinating much better. By the results of pot experiment(rice straw powder dosage / area) to conversion, when rice straw powder per acre application was 450 kg, the controlling rate of Chenopodium glaucum can be up to 85%.This is a huge usage, consider rice straw powder use with herbicide, or use the allelopathic substance in rice straw after purification. |
