Comparative analysis of weed communities associated with upland rice in four consecutive wet season
1995
Galinato, M.I. (Visayas State Coll. of Agriculture, Baybay, Leyte (Philippines))
An ecological survey of the weed species and communities associated with upland rice in the farmers' fields was conducted in three villages of Matalom-San Salvador, Elevado and Esperanza from 1991 to 1994 wet seasons. Quantitative vegetation analysis was done. The ordination method of Bray and Curtis (1957) was used to analyze the data. Wet season quantitative vegetation analysis showed that there was fluctuation in the number of dominant weed communities and species associated with upland rice. In 1991, there were 8 dominant weed communities with 56 weed species belonging to 18 families; in 1992 the number of weed communities was maintained but some communities disappeared with 48 species assigned to 14 families recorded; in 1993 the communities increased to 12 with 57 weed species and 18 families; and in 1994, nine weed communities, 60 weed species and 16 families were noted. The correlation coefficient computed for each season was significant (r = 0.7) suggesting that aggregation of sample plots was indeed indicating distinct community types. Possible reasons for the shift in weed communities were given
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