Diversity of weeds in kiwifruit orchards in Guizhou.
Objective: The present paper was conducted to definite the characteristics of weed community in kiwifruit orchards and provide the basis for prevention and control of weeds in kiwifruit orchards in Guizhou. Method: The weed communities in kiwifruit orchards in Shuicheng and Xiuwen county were investigated by a visual observation. Result: 100 weed species, 34 families were found in 11 sample plots and the species of Asteraceae, Gramineae, Polygonacaea and Lamiaceae were 26, 13, 9 and 5 respectively. The number of invasive alien weed species was 20 and 60% species of total invasive alien weeds belonged to Asteraceae. The occurrence frequency of Digitaria sanguinalis. Galinsoga quadriradiata and Artemisia lavandulaefolia reached 90.91%, 81.82% and 72.73% respectively. Five weed species with the maximum niche breadth value were Solanum nigrum, Digitaria sanguinalis, Crassocephalum crepidioides, Artemisia lavandulaefolia and Commelina communis. Some invasive alien weed species such as Solanum nigrum, Digitaria sanguinalis, Crassocephalum crepidioides, Artemisia lavandulaefolia and Commelina communis occurred in kiwifruit orchards seriously. There are 24.73 weed species in each sample plot averagely. The average value of Shannon index, Pielou index, Jaccard differential index and Bray-Curtis differential index are 14.41, 0.84, 0.82 and 0.82, respectively. Conclusion: The weed diversity of kiwifruit orchards is very high and the invasive alien weed species bring about serious challenges to prevention and control of weeds in kiwifruit orchards in Guizhou.