Weed diversity in tea gardens in Guizhou.
Objective: To lay the foundation for prevention and control of weeds in tea gardens by finding out weed diversity in Guizhou. Method: The dominance levels of various weeds in 61 sample plots of 13 tea gardens were recorded by a seven-level ocular estimation method. Result: 134 weed species, 41 families are found in 61 sample plots. 28 and 22 weed species among 134 weed species belong to Asteraceae and Poaceae respectively. 23 weed species are invasive alien weeds and there are 6.23 invasive alien weed species in each sample plot averagely. The weed species with the top 10 occurrence frequency are Pteridium aquilinum, Crassocephalum crepidioides, Microstegium vimineum, Oxalis corniculata, Conyza sumatrensis, Phytolacca americana, Polygonum posumbu, Digitaria sanguinalis, Achyranthes bidentata and Conyza canadensis The weed species with the top 10 niche breadth are Conyza sumatrensis, Microstegium vimineum, Pteridium aquilinum, Oxalis corniculata, Solanum nigrum, Crassocephalum crepidioides, Phytolacca americana, Digitaria sanguinalis, Achyranthes bidentata and Ageratum conyzoides. The Shannon and Pielou index of weed communities in 13 tea gardens is 2.54-29.44 with an average of 14.54 and 0.41-0.87 with an average of 0.73 separately. The average Jaccard and Bray-Curtis difference index is 0.79 and 0.75 respectively. Conclusion: The weed specie is of high diversity in tea gardens and the serious weed damage are from Asteraceae, Phytolacca acinosa Roxb, Pteridophyta and invasive alien weeds in Guizhou.