SAMPLING SIZE TO ESTIMATE THE QUANTITY OF RED RICE SEEDS, IN CULTIVATED SOILS

[摘要] A sampling experiment was conducted in order to determine the best sampling size to estimate the quantity of red rice seeds in soil. Four sampling sizes 10cm deep were collected in a lowland area infested with red rice located in the Campus of ESALQ/USP during 1988/89. There was great heterogeinity in seed distribution and there were necessary about 30 soil samples varying between 0,375 up to 0,5m2 in order that differences above 20% of average to be significant at the 5% error probability. The method was neither adequate nor practical due amount of time and work required to do it.

[学科分类] 农业科学（综合）

[关键词] red rice;seeds;buried seed bank;sampling