29 results on '"Guimei Jin"'
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2. Allelopathic Molecular Mechanisms of the Two Main Allelochemicals in Sweet Potato
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Ruiguo Shi, Guimei Jin, Shicai Shen, Gaofeng Xu, Fengping Zheng, David Roy Clements, Yunhai Yang, Shaosong Yang, Fanghao Wan, Fudou Zhang, and Bo Liu
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sweet potato ,palmitic acid ,linoleic acid ,allelopathic effects ,transcriptomics ,metabolomics ,Biology (General) ,QH301-705.5 - Abstract
Sweet potato (Ipomoea batatas L.) is one of the most important global food crops. This crop exhibits excellent allelopathic potential against various weeds, but its allelopathic mechanism at the molecular level is unclear. Therefore, metabolomic and transcriptomic analyses were performed to explore the allelopathic effects, metabolic pathway, and associated genes for two major compounds with allelopathic activity, palmitic acid and linoleic acid. The sweet potato variety Ningshu 25 was employed in the current study. The results showed that palmitic acid and linoleic acid had strong allelopathic effects on seed germination, plant growth, antioxidant enzyme activity, and chlorophyll content of two weeds Digitaria sanguinalis and Bidens pilosa. The content of the two targeted metabolites was affected by different environmental conditions and was significantly increased under low temperature (15 °C). Five metabolic pathways involved in the two targeted metabolites of fatty acids were found: fatty acid biosynthesis, fatty acid elongation, fatty acid degradation, biosynthesis of cutin, suberine, and wax, and the linoleic acid metabolism pathway. The synthesis of palmitic acid is significantly enriched in the biosynthesis pathways of fatty acids, cutin, suberine, and wax, and the synthesis of linoleic acid is significantly enriched in the linoleic acid metabolism pathway. Under different environmental conditions, there were three key genes expressed—g4988, g11881, and g19673—located in the biosynthesis pathways of cutin, suberine, and wax; four key genes expressed—g31191, g60956, g49811, and g59542—located in the biosynthesis pathway of fatty acids; and six key expressed genes—g26575, g24787, g23517, g57649, g58562, and g4314—located in biosynthesis pathway of linoleic acid, respectively. Our study advances understanding of the molecular mechanisms behind allelopathic traits in sweet potato and provides a set of candidate genes for use in improving allelopathic potential in sweet potato germplasm resources.
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- 2024
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3. Potential distribution and ecological impacts of Acmella radicans (Jacquin) R.K. Jansen (a new Yunnan invasive species record) in China
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Shicai Shen, Fengping Zheng, Wei Zhang, Gaofeng Xu, Diyu Li, Shaosong Yang, Guimei Jin, David Roy Clements, Emma Nikkel, Aidong Chen, Yuchen Cui, Zewen Fan, Lun Yin, and Fudou Zhang
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New invasive species ,Acmella radicans ,Potential distribution ,Predictive modeling ,MaxEnt ,Ecological impact ,Botany ,QK1-989 - Abstract
Abstract Background Acmella radicans (Jacquin) R.K. Jansen is a new invasive species record for Yunnan Province, China. Native to Central America, it has also been recently recorded invading other parts of Asia. To prevent this weed from becoming a serious issue, an assessment of its ecological impacts and potential distribution is needed. We predicted the potential distribution of A. radicans in China using the MaxEnt model and its ecological impacts on local plant communities and soil nutrients were explored. Results Simulated training using model parameters produced an area under curve value of 0.974, providing a high degree of confidence in model predictions. Environmental variables with the greatest predictive power were precipitation of wettest month, isothermality, topsoil TEB (total exchangeable bases), and precipitation seasonality, with a cumulative contribution of more than 72.70% and a cumulative permutation importance of more than 69.20%. The predicted potential suitable area of A. radicans in China is concentrated in the southern region. Projected areas of A. radicans ranked as high and moderately suitable comprised 5425 and 26,338 km2, accounting for 0.06 and 0.27% of the Chinese mainland area, respectively. Over the 5 years of monitoring, the population density of A. radicans increased while at the same time the population density and importance values of most other plant species declined markedly. Community species richness, diversity, and evenness values significantly declined. Soil organic matter, total N, total P, available N, and available P concentrations decreased significantly with increasing plant cover of A. radicans, whereas pH, total K and available K increased. Conclusion Our study was the first to show that A. radicans is predicted to expand its range in China and may profoundly affect plant communities, species diversity, and the soil environment. Early warning and monitoring of A. radicans must be pursued with greater vigilance in southern China to prevent its further spread.
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- 2024
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4. Effects of Acmella radicans Invasion on Soil Seed Bank Community Characteristics in Different Habitats
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Xiaohan Wu, Kexin Yang, Fengping Zheng, Gaofeng Xu, Zewen Fan, David Roy Clements, Yunhai Yang, Shaosong Yang, Guimei Jin, Fudou Zhang, and Shicai Shen
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Acmella radicans ,soil seed bank ,seed density ,species diversity ,invasive plant ,Botany ,QK1-989 - Abstract
To examine the effects of the recent Acmella radicans invasion on plant community and diversity in invaded habitats, the composition, density, species richness, diversity indices, and evenness index of the soil seed bank community of two different habitats (wasteland and cultivated land) in Yunnan Province, China, were analyzed through field sampling and greenhouse germination tests. A total of 28 species of plants belonging to 15 families and 28 genera, all annual herbs, were found in the soil seed bank. Seed densities and species number in the seed bank tended to be greater in April than in October; cultivated land also featured higher seed densities and species numbers compared to wasteland. With increased A. radicans cover, the seed bank population of A. radicans also significantly increased, but the seed bank populations of many other dominant species (e.g., Ageratum conyzoides and Gamochaeta pensylvanica) and native species (e.g., Laggera crispata and Poa annua) clearly declined. The germination of A. radicans seeds was concentrated during the period from the 4th to the 5th weeks. Vertically, the seed number of A. radicans was significantly different among the 0–5 cm, 5–10 cm and 10–20 cm layers that accounted for 80.7–90.6%, 9.4–16.1% and 0.0–3.2% of the total seed density in wasteland, respectively; and in cultivated land, A. radicans accounted for 56.8–64.9%, 26.7–31.8% and 8.1–13.5% of the total seed density, respectively. With reduced A. radicans cover, the species richness, Simpson index, Shannon–Wiener index, and Pielou indices of the weed community generally increased, and most diversity indices of weed communities in cultivated land were lower than in wasteland under the same cover of A. radicans. The results indicate that the invasion of A. radicans has negatively affected local weed community composition and reduced weed community diversity, and that these negative impacts in cultivated land may be enhanced by human disturbance. Our study was the first to elucidate the influence of A. radicans invasion on soil seed bank community characteristics in invaded habitats, providing a better understanding of its invasion and spread mechanisms in order to aid in developing a scientific basis for the prevention and control of this invader.
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- 2024
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5. Allelopathic Potential and Chemical Composition of Essential Oil from the Invasive Plant Acmella radicans
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Kexin Yang, Yunhai Yang, Xiaohan Wu, Fengping Zheng, Gaofeng Xu, Shaosong Yang, Guimei Jin, David Roy Clements, Shicai Shen, and Fudou Zhang
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alien plants ,bioassays ,phytotoxic ,competitive ability ,GC-MS ,extraction ,Agriculture - Abstract
Acmella radicans (Jacquin) R.K. Jansen is a new invasive species recorded in Yunnan Province, China, and little is known about its allelopathic potential and allelochemicals. In this study, the allelopathic effects of the essential oil (EO) of A. radicans on seed germination and seedling growth of four common plants, Brassica napus, Brassica rapa ssp. chinensis, Digitaria sanguinalis, and Lolium multiflorum, were explored. The results showed that the seed germination index, germination rate, root length, stem length, and biomass of B. napus and B. rapa ssp. chinensis were significantly inhibited at all EO concentrations of A. radicans, but there was a ‘low-promotion and high-inhibition effect’ on the root length of D. sanguinalis and L. multiflorum at low concentrations of 0.5 μL·mL−1 and 0.5–1.0 μL·mL−1, respectively. With increasing concentrations of EO, the inhibition rates of seed germination and seedling growth of four common plants gradually increased, and D. sanguinalis and L. multiflorum were the most inhibited, followed by B. rapa ssp. chinensis, and the least inhibited was B. napus. Thirty-two components were identified using GC–MS, representing 99.07% of the EO in A. radicans. The major components were 2-tridecanone (30.46%), caryophyllene oxide (19.18%), 4,8,11,11-tetramethylbicyclo[7.2.0]undec-3-en-5-ol (7.84%), β-caryophyllene (7.67%), and widdrol (4.7%). Among the compounds we identified, (E,E)-2,4-decadienal, 2-tridecanone, γ-cadinene, δ-cadinene, (E)-α-cadinol, spathulenol, caryophyllene oxide, and widdrol have been previously reported as having possible allelopathic effects. Our study was the first to show that A. radicans could potentially release allelochemicals to influence neighboring plants during its invasion and expansion.
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- 2024
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6. Sweet potato (Ipomoea batatas) and hyacinth bean (Lablab purpureus) in combination provide greater suppression of mile-a-minute (Mikania micrantha) than either crop alone
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Shicai Shen, Gaofeng Xu, Guangzong Ma, Diyu Li, Shaosong Yang, Guimei Jin, David Roy Clements, Aidong Chen, Lina Wen, Yuchen Cui, Li Chuan, Fudou Zhang, and Bo Liu
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sweet potato ,hyacinth bean ,mile-a-minute ,multispecies competition ,soil nutrients ,Plant culture ,SB1-1110 - Abstract
IntroductionIn natural systems, diverse plant communities tend to prevent a single species from dominating. Similarly, management of invasive alien plants may be achieved through various combinations of competing species.MethodsWe used a de Wit replacement series to compare different combinations of sweet potato (Ipomoea batatas (L.) Lam), hyacinth bean (Lablab purpureus (L.) Sweet) and mile-a-minute (Mikania micrantha Kunth) through measures of photosynthesis, plant growth, nutrient levels in plant tissue and soil, and competitive ability.ResultsCultured alone sweet potato and hyacinth beans exhibited higher total biomass, leafstalk length, and leaf area than mile-a-minute. In mixed culture, either sweet potato or hyacinth bean or both together significantly suppressed the mile-a-minute parameters, i.e., plant height, branch, leaf, adventitious root, and biomass (P
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- 2023
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7. Potential use of Helianthus tuberosus to suppress the invasive alien plant Ageratina adenophora under different shade levels
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Shicai Shen, Gaofeng Xu, Diyu Li, Shaosong Yang, Guimei Jin, Shufang Liu, David Roy Clements, Aidong Chen, Jia Rao, Lila Wen, Qiong Tao, Shuiying Zhang, Jiazhen Yang, and Fudou Zhang
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Helianthus tuberosus ,Ageratina adenophora ,Shade levels ,Competitive interactions ,Growth suppression ,Net photosynthetic rate ,Ecology ,QH540-549.5 ,Evolution ,QH359-425 - Abstract
Abstract Background An ecological approach for managing biological invasions in agroecosystems is the selection of alternative crop species to manage the infestation of invasive alien plants through competition. In the current study, plant growth, photosynthesis, and competitive ability of the crop Helianthus tuberosus L. (Jerusalem artichoke) and the invasive alien plant Ageratina adenophora (Spreng.) R. M. King and H. Rob were compared under varying shade levels by utilizing a de Wit replacement series method. We hypothesized that H. tuberosus had higher competitive ability than A. adenophora even under shaded conditions. Results The results showed the main stem, leafstalk length, leaf area, underground biomass, and aboveground biomass of A. adenophora were significantly lower compared to H. tuberosus in monoculture although A. adenophora had a greater number of branches that were longer on average. Under full sunlight, the total shoot length (stem + branch length), main stem length and branch length of A. adenophora were significantly suppressed (P
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- 2021
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8. Allelochemicals Identified From Sweet Potato (Ipomoea batatas) and Their Allelopathic Effects on Invasive Alien Plants
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Shicai Shen, Guangzong Ma, Gaofeng Xu, Diyu Li, Guimei Jin, Shaosong Yang, David Roy Clements, Aidong Chen, Lina Wen, Fudou Zhang, and Min Ye
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sweet potato ,allelochemicals ,allelopathic effects ,invasive plants ,weed management ,Plant culture ,SB1-1110 - Abstract
Sweet potato [Ipomoea batatas (L.) Lam] is grown as important cash and food crop worldwide and has been shown to exhibit allelopathic effects on other plants. However, its metabolome has not been studied extensively, particularly with respect to the production of phytotoxic bioactive secondary products. In this study, the chemical composition of petroleum ether extract of sweet potato was characterized, and the morphological and physiological effects of some individual components against four invasive alien weeds Bidens pilosa L., Galinsoga parviflora Cav., Lolium multiflorum Lam., and Phalaris minor Retz. were determined. Twenty-one components were identified by GS-MS, constituting 96.08% of petroleum ether extract in sweet potato. The major components were palmitic acid (PA) (17.48%), ethyl linoleate (EL) (13.19%), linoleic acid (LA) (12.55%), ethyl palmitate (EP) (11.77%), ethyl linolenate (ELL) (8.29%) oleic acid (5.82%), ethyl stearate (4.19%), and 3-methylphenol acetate (3.19%). The five most abundant compounds exhibited strong inhibition activity against the four invasive weeds tested. The highest inhibition rates were seen for LA, followed by PA and EP, respectively. Catalase (CAT), malondialdehyde (MDA), and peroxidase (POD) content of L. multiflorum were increased by the three allelochemicals, i.e., LA, PA and EP, but superoxide dismutase (SOD), chlorophyll-a and chlorophyll-b levels declined. Overall, the combined impact of all five compounds could be quite effective in suppressing the invasive weeds of concern.
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- 2022
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9. Agrobiodiversity and in situ conservation in ethnic minority communities of Xishuangbanna in Yunnan Province, Southwest China
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Shicai Shen, Gaofeng Xu, Diyu Li, David Roy Clements, Fudou Zhang, Guimei Jin, Jianyong Wu, Pingfang Wei, Song Lin, and Dayuan Xue
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Xishuangbanna ,Agrobiodiversity ,Diversity change ,In situ conservation ,Ethnic minority ,Other systems of medicine ,RZ201-999 ,Botany ,QK1-989 - Abstract
Abstract Background Xishuangbanna of Yunnan Province, southwest of China belongs to a global biodiversity and cultural hotspot. Agrobiodiversity plays an essential role in local livelihoods and traditional culture in the region. However, preliminary studies suggest that diversity of crop plants and livestock species is declining. We hypothesized that agrobiodiversity and traditional means of preserving agrobiodiversity are threatened because of changes in government policy in favor of commercial plantations, land use change and changes in traditional agricultural practices. We investigated whether or not agrobiodiversity was declining, the specific causes, and signs of active biodiversity conservation practices in ethnic minority communities of Xishuangbanna which could form the basis for extensive in situ conservation programmes. Methods A series of field studies to document trends in agrobiodiversity were conducted in different ethnic minority communities in Menghai County, Mengla County and Jinghong City of Xishuangbanna of Yunnan Province, southwest of China between July 2015 and February 2016. Data was obtained through the use of semi-structured questionnaires, field observation and participatory rural appraisal (PRA) tools. A total of 360 ethnic households provided information on current status, functions, characteristics, changes, and threatened factors of farming crop and livestock resources. Some measures for in situ conservation of agricultural biological resources were also researched using PRA methods. Results Two hundred twenty-six crop varieties belonging to 31 families, 71 genera and 101 species were identified in Xishuangbanna, which included 83 vegetable crops, 77 food crops, 24 spice crops, 22 fruit crops, 13 cash crops, 6 oil crops, and 1 cloth crop, respectively. There were 15 livestock varieties, belonging to 6 major species: cattle, pigs, goats, chickens, ducks, and geese. Different crop and livestock resources had their own characteristics, functions and threatened factors. Since 2002, agroecosystem, crop diversity and livestock diversity have declined greatly over the Xishuangbanna region as a whole under implementation of the Sloping Land Conversion Program (SLCP). Swidden agriculture was completely eliminated under this program and gradually replaced by large land areas devoted to rubber, tea and banana plantations. Villager numbers engaging in farming production and population of crops and livestock were greatly decreased, particularly in terms of production of local traditional varieties. However, some in situ conservation measures such as seeds preservation, planting of traditional crops and raising livestock have played an important role in local agrobiodiversity conservation. Conclusion Abundant agricultural resources and agrobiodiversity are critical to the local livelihood and maintenance of traditional culture in Xishuangbanna. However, agrobiodiversity and related traditional culture have been greatly impacted by implementation of the SLCP since 2002. Therefore, in future conservation of agrobiodiversity, incorporating some sustainable protection measures based in local communities such as convening seed exchange fairs, conserving traditional varieties in permanent plots, making a visual documentary of indigenous cultivation, and providing traditional agricultural products to tourists should be carefully considered and adopted.
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- 2017
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10. Potential Use of Sweet Potato (Ipomoea batatas (L.) Lam.) to Suppress Three Invasive Plant Species in Agroecosystems (Ageratum conyzoides L., Bidens pilosa L., and Galinsoga parviflora Cav.)
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Shicai Shen, Gaofeng Xu, Diyu Li, Guimei Jin, Shufang Liu, David Roy Clements, Yanxian Yang, Jia Rao, Aidong Chen, Fudou Zhang, Xiaocheng Zhu, and Leslie A. Weston
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competitive crops ,weed–crop competition ,sweet potato ,Ipomoea batatas (L.) Lam. ,Ageratum conyzoides L. ,Bidens pilosa L. ,Galinsoga parviflora Cav. ,antioxidant enzymes ,de Wit replacement series ,Agriculture - Abstract
Sweet potato (Ipomoea batatas (L.) Lam.) is a logical candidate crop to suppress invasive plants, but additional information is needed to support its potential application as a suppressive ground cover. The current study utilized a de Wit replacement series incorporating five ratios of sweet potato grown in the field in combination with one of three invasive plants (Ageratum conyzoides L., Bidens pilosa L., and Galinsoga parviflora Cav.) in replicated 9 m2 plots. Stem length, total biomass, and leaf area were higher for monoculture-grown sweet potato than these parameters for any of the invasive plants grown in monoculture. In mixed culture, the plant height, branch, leaf, inflorescence, seed, and biomass of all invasive plants were suppressed by sweet potato. The relative yield parameter indicated that intraspecific competition was greater than interspecific competition for sweet potato, while the reverse was true for invasive species. The net photosynthetic rate was higher for sweet potato than for B. pilosa and G. parviflora but not A. conyzoides. Superoxide dismutase and peroxidase activities of each of the three invasive plants were reduced in mixture with sweet potato. Our results demonstrated that these three invasive plants were significantly suppressed by sweet potato competition due to the rapid growth and phenotypic plasticity of sweet potato.
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- 2019
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11. Swidden agriculture and sloping land conversion in China's Dulong Valley: impact and adaptation.
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Shen ShiCai, Shen ShiCai, primary, Li DiYu, Li DiYu, additional, Zhang FuDou, Zhang FuDou, additional, Xu GaoFeng, Xu GaoFeng, additional, Wilkes, A., additional, Yin Lun, Yin Lun, additional, and Jin GuiMei, Jin GuiMei, additional
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- 2017
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12. Increased suppressive effect of Ipomoea batatas (sweet potato) on Mikania micrantha (mile-a-minute) under high fertilization levels
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Shicai Shen, Yanxian Yang, Gaofeng Xu, Fudou Zhang, David R. Clements, Diyu Li, Xiaofen Yu, Aidong Chen, Shaosong Yang, Leslie A. Weston, Shufang Liu, Xiaocheng Zhu, and Guimei Jin
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Horticulture ,Growth suppression ,Human fertilization ,Ecology ,Soil nutrients ,Management, Monitoring, Policy and Law ,Biology ,Ipomoea ,biology.organism_classification ,Mikania micrantha ,Ecology, Evolution, Behavior and Systematics - Published
- 2020
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13. Allelochemicals Identified From Sweet Potato (
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Shicai, Shen, Guangzong, Ma, Gaofeng, Xu, Diyu, Li, Guimei, Jin, Shaosong, Yang, David Roy, Clements, Aidong, Chen, Lina, Wen, Fudou, Zhang, and Min, Ye
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Sweet potato [
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- 2021
14. Allelopathic potential of sweet potato (Ipomoea batatas) germplasm resources of Yunnan Province in southwest China
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Shufang Liu, Gaofeng Xu, Diyu Li, Aidong Chen, Shicai Shen, Fudou Zhang, Yanxian Yang, Guimei Jin, David R. Clements, and Hisashi Kato-Noguchi
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0106 biological sciences ,Germplasm ,biology ,fungi ,food and beverages ,Lactuca ,04 agricultural and veterinary sciences ,General Medicine ,Ipomoea ,biology.organism_classification ,01 natural sciences ,Horticulture ,Germination ,Shoot ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Bioassay ,Cultivar ,Allelopathy ,010606 plant biology & botany - Abstract
A laboratory bioassay was conducted to determine the allelopathic potentials of aqueous extracts from either roots or leaves of seventeen sweet potato [Ipomoea batatas L. (Lam)] cultivars (SP0, SP1, SP2, SP3, SP4, SP5, SP6, SP7, SP9, SP10, SP11, SP13, SP14, SP15, SP16, SP18, and SP19). Most inhibitory rates on Lactuca sativa calculated for leaf or root extracts from the seventeen sweet potato cultivars exhibited positive values and significantly increased with increasing concentration. Germination was totally inhibited at a concentration of 0.05 g·mL−1 for leaf water extracts of SP13, SP15, SP18 and at a concentration of 0.05 g·mL−1 for both leaf and root water extracts of SP19. Inhibition of root length was clearly greater than inhibition of shoot length for both leaf and root water extracts. Biomass inhibition increased with increasing concentration, but some cultivars showed stimulatory effects at low concentrations, and inhibition was generally more pronounced for root water extracts than for leaf water extracts. Moreover, most synthetical inhibitory rates for both leaf and root water extracts from the seventeen cultivars exhibited positive values and significantly increased with increasing concentration. Comparing the synthetical inhibitory rates for both leaf and root water extracts among the seventeen cultivars, SP19, SP6, SP11, and SP7 had the highest allelopathic inhibition. The inhibitory activity on germination index was the greatest, followed by germination rate, root length, biomass, and shoot length in all bioassays. Inhibition by leaf water extracts was generally greater than inhibition by root water extracts, except in the case of shoot length or biomass. Overall, we conclude that all seventeen sweet potato cultivars have strong inhibitory effects on L. sativa, but that these effects vary with cultivar and plant part, with SP19, SP6, SP11, and SP7 exhibiting the highest rates of allelopathic inhibition.
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- 2018
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15. The current status of biological control of weeds in southern China and future options
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Michael D. Day, Shicai Shen, Yanxian Yang, Guimei Jin, Rui Gao, Gaofeng Xu, Xingxiang Yin, Shufang Liu, Rachel L. Winston, Diyu Li, Fudou Zhang, and Qing Zhang
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0106 biological sciences ,Food security ,business.industry ,Agroforestry ,fungi ,Biological pest control ,food and beverages ,General Medicine ,respiratory system ,Weed control ,010603 evolutionary biology ,01 natural sciences ,010602 entomology ,Southern china ,Agriculture ,parasitic diseases ,China ,business ,Weed ,Productivity - Abstract
China has become one of the countries most seriously affected by invasive alien weeds in the world. Weeds impact agriculture, the environment and human health, and conventional control methods such as herbicides are expensive, damaging to human health and unsustainable. As the impacts and costs of weed control in China increase, there is an urgent need to manage some of the more important weeds through more sustainable methods. Classical biological control of invasive alien weeds is environmentally-friendly and sustainable. Biological control in China began in the 1930s with the introduction of two agents into Hong Kong for the control of Lantana camara. Since then, a further seven biological control agents have been introduced into China to control four weed species. In addition, 11 biological control agents targeting seven weed species have naturally spread into China. Together, these biological control agents are helping to control some of China's worst weeds. However, these efforts are only a small portion of the weeds that could be targeted for weed biological control. This paper reviews the current status of weed biological control efforts against introduced weeds in ten provinces and regions in southern China and provides a platform to identify the most effective and appropriate weed biological control opportunities and programmes to pursue in the future. Introducing additional safe and effective biological control agents into China to help manage some of the worst weeds in the region should reduce the use of herbicides and impacts on human health and the environment, while increasing productivity and food security.
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- 2018
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16. Occurrence and damage of invasive alien plants in Dehong Prefecture, western of Yunnan Province
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Xingxiang Yin, Fudou Zhang, Gaofeng Xu, Diyu Li, Shicai Shen, Rui Gao, David R. Clements, and Guimei Jin
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0106 biological sciences ,Perennial plant ,Ecology ,Agroforestry ,business.industry ,fungi ,food and beverages ,General Medicine ,Fabaceae ,Alien ,Biology ,010603 evolutionary biology ,01 natural sciences ,Invasive species ,Crop ,Habitat ,Agriculture ,Poaceae ,business ,010606 plant biology & botany - Abstract
Alien invasive plants are a serious threat to natural and agricultural systems, especially in areas with sensitive habitats and high value crops. Dehong Prefecture, western Yunnan Province, China is vulnerable to invasive plants and its current status of invasive alien plants is assessed in this article. We compiled a comprehensive list of invasive alien plants with background information from 2013 to 2015, including origin, life form, habit, distribution, affected crop, and damage. The 90 invasive alien plant species in Dehong Prefecture are represented by 28 families and 66 genera, with the three largest families, Asteraceae, Poaceae and Fabaceae, accounting for 48.9% of all species. The proportion of invasive alien plants originating from the Americas, Europe, Asia, and Africa were 68%, 11%, 10%, and 9%, respectively. Almost all invasive alien plants were found in five cities or counties in Dehong Prefecture, and there were more invasive plant species in Ruili City, Luxi City, Yijiang County, and Longchuan County than Lianghe County. Most invasive alien plants were herbs (84.4%), with annual and perennial plants forming equal proportions (both comprised 43.3%). There were 44 invasive plant species rated as causing minor damage, destructive I grade (49% of all species), followed by 27 species rated at intermediate II grade (30%) and 19 species at heavy damage III grade (21%). Most invasive alien plants were both agricultural and environmental species thus negatively impacting both crop production and ecosystems, often significantly. The major infested crops were vegetables, sugarcane, maize, and orchard crops. Given the large number of alien plant invaders, it was concluded that Dehong Prefecture has become a major “window” for foreign alien plants entering in Yunnan Province and even for China as a whole. More attention should be paid to this issue, and effective measures should be developed to manage the expansion and damage caused by invasive alien plants.
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- 2017
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17. Allelopathic Effects of Three Sweet Potato Cultivars (Ipomoea batatas) on the Invasive Plant Mikania micrantha
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Shicai Shen, Yanxian Yang, Aidong Chen, Gaofeng Xu, Diyu Li, Kato-Noguchi Hisashi, Fudou Zhang, Guimei Jin, David R. Clements, and Shufang Liu
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0106 biological sciences ,China ,Mikania ,Biology ,Ipomoea ,01 natural sciences ,Pheromones ,Soil ,Cultivar ,Biomass ,Ipomoea batatas ,Mikania micrantha ,Allelopathy ,Water ,04 agricultural and veterinary sciences ,Weed control ,biology.organism_classification ,Plant Leaves ,Horticulture ,Seedling ,Seedlings ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Weed ,Agronomy and Crop Science ,010606 plant biology & botany - Abstract
Background and objectives Sweet potato [Ipomoea batatas (L.) Lam] is an important locally grown cash crop in China; it was demonstrated to suppress the invasive plant Mikania micrantha (M. micrantha) H.B.K through strong competitiveness, but its allelopathic effects on this weed were unknown. The present study aimed to explore the allelopathic potential of sweet potato on M. micrantha. Materials and methods The allelopathic effects of water extracts and soil incorporation from leaves of three sweet potato cultivars (SP1, SP0 and SP9) on the sprout seedling growth of invasive plant M. micrantha in Yunnan Province, China, were studied under laboratory and greenhouse conditions. Results Stem length, root biomass, aboveground biomass and total biomass of M. micrantha were significantly reduced with increasing concentration in both leaf water extracts and leaf soil incorporation of three sweet potato cultivars. Among these, SP1 had the strongest inhibition and the next highest impact was from SP0 with the lowest effect from SP9. The highest inhibition rates were seen for root biomass, followed by total biomass, whereas the lowest impact was on aboveground biomass. The strong correspondence between results for both leaf water extracts and leaf soil incorporation provided a good demonstration that compounds produced by sweet potato have allelopathic effects on M. micrantha. The general inhibition of M. micrantha by sweet potato followed the order among the three sweet potato cultivars tested as SP1, SP0 and SP9. Moreover, the synthetical allelopathic indices of leaf soil incorporation of three cultivars on M. micrantha were generally higher than these of leaf water extracts. Conclusion Competition and allelopathy have primarily been seen as separate ecological weed management tools, but as these have demonstrated in the case of sweet potato where both mechanisms inhibit weed growth, there is potential for synergism between competition and allelopathy in the reduction of weed infestations.
- Published
- 2018
18. Competitive and Allelopathic Effects of Wild Rice Accessions (Oryza longistaminata) at Different Growth Stages
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Gaofeng Xu, Guimei Jin, Fudou Zhang, Shicai Shen, Peng Xu, David R. Clements, and Dayun Tao
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0106 biological sciences ,biology ,media_common.quotation_subject ,food and beverages ,Sowing ,Oryza longistaminata ,04 agricultural and veterinary sciences ,biology.organism_classification ,01 natural sciences ,Competition (biology) ,Horticulture ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Cultivar ,Weed ,Agronomy and Crop Science ,Allelopathy ,010606 plant biology & botany ,media_common - Abstract
The competitive and allelopathic effects of wild rice (Oryza longistaminata) accessions on barnyard grass at different growth stages determined by days after sowing (0, 30, 60 and 90 days) were studied in greenhouse pot experiments. Wild rice accession RL159 exhibited the greatest height and tillering. The weed suppression rates of wild rice accessions OL and F1 on barnyard grass were significantly higher than for other rice accessions, with the lowest being O. sativa cultivar RD23. The highest suppression rates of OL and F1 were 80.23 and 73.96% at barnyard grass growth stages of 90 days and 60 days. At a 90 growth stage, wild rice accessions RL159 and RL169 caused 61.33 and 54.51% inhibition in barnyard grass growth, respectively. Under the same conditions, the competitive inhibition rates of OL, F1, RL159, RL169 and RL219 against barnyard grass were markedly lower than their weed suppressive effects, but were relatively similar for RD23. The allelopathic inhibition of OL and F1 on barnyard grass was significantly higher than other rice accessions. The highest allelopathic rates of OL and F1 were 60.61 and 56.87% at the 0 day growth stage. It is concluded that wild rice accessions OL and F1 exhibited the highest allelopathic activity along with moderate competitive ability against barnyard grass; wild rice accession RL159 had the highest competitive ability and moderate allelopathic activity on barnyard grass. Thus, the three wild rice accessions OL, F1 and RL159 could be used as ideal breeding materials for cultivated rice improvement.
- Published
- 2017
19. Agrobiodiversity and in situ conservation in ethnic minority communities of Xishuangbanna in Yunnan Province, Southwest China
- Author
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Fudou Zhang, Jianyong Wu, Diyu Li, Shicai Shen, Dayuan Xue, Song Lin, Gaofeng Xu, Guimei Jin, Pingfang Wei, and David R. Clements
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0106 biological sciences ,Cultural Studies ,Crops, Agricultural ,In situ conservation ,China ,Conservation of Natural Resources ,Health (social science) ,Livestock ,010504 meteorology & atmospheric sciences ,Cash crop ,Population ,Diversity change ,01 natural sciences ,Environmental protection ,lcsh:Botany ,Ethnicity ,Animals ,Humans ,education ,Xishuangbanna ,Minority Groups ,0105 earth and related environmental sciences ,education.field_of_study ,Agroforestry ,business.industry ,Research ,lcsh:Other systems of medicine ,Biodiversity ,lcsh:RZ201-999 ,lcsh:QK1-989 ,Agrobiodiversity ,Geography ,Complementary and alternative medicine ,Crop diversity ,Agriculture ,Threatened species ,Ethnic minority ,Agricultural biodiversity ,Plants, Edible ,General Agricultural and Biological Sciences ,business ,010606 plant biology & botany - Abstract
Background Xishuangbanna of Yunnan Province, southwest of China belongs to a global biodiversity and cultural hotspot. Agrobiodiversity plays an essential role in local livelihoods and traditional culture in the region. However, preliminary studies suggest that diversity of crop plants and livestock species is declining. We hypothesized that agrobiodiversity and traditional means of preserving agrobiodiversity are threatened because of changes in government policy in favor of commercial plantations, land use change and changes in traditional agricultural practices. We investigated whether or not agrobiodiversity was declining, the specific causes, and signs of active biodiversity conservation practices in ethnic minority communities of Xishuangbanna which could form the basis for extensive in situ conservation programmes. Methods A series of field studies to document trends in agrobiodiversity were conducted in different ethnic minority communities in Menghai County, Mengla County and Jinghong City of Xishuangbanna of Yunnan Province, southwest of China between July 2015 and February 2016. Data was obtained through the use of semi-structured questionnaires, field observation and participatory rural appraisal (PRA) tools. A total of 360 ethnic households provided information on current status, functions, characteristics, changes, and threatened factors of farming crop and livestock resources. Some measures for in situ conservation of agricultural biological resources were also researched using PRA methods. Results Two hundred twenty-six crop varieties belonging to 31 families, 71 genera and 101 species were identified in Xishuangbanna, which included 83 vegetable crops, 77 food crops, 24 spice crops, 22 fruit crops, 13 cash crops, 6 oil crops, and 1 cloth crop, respectively. There were 15 livestock varieties, belonging to 6 major species: cattle, pigs, goats, chickens, ducks, and geese. Different crop and livestock resources had their own characteristics, functions and threatened factors. Since 2002, agroecosystem, crop diversity and livestock diversity have declined greatly over the Xishuangbanna region as a whole under implementation of the Sloping Land Conversion Program (SLCP). Swidden agriculture was completely eliminated under this program and gradually replaced by large land areas devoted to rubber, tea and banana plantations. Villager numbers engaging in farming production and population of crops and livestock were greatly decreased, particularly in terms of production of local traditional varieties. However, some in situ conservation measures such as seeds preservation, planting of traditional crops and raising livestock have played an important role in local agrobiodiversity conservation. Conclusion Abundant agricultural resources and agrobiodiversity are critical to the local livelihood and maintenance of traditional culture in Xishuangbanna. However, agrobiodiversity and related traditional culture have been greatly impacted by implementation of the SLCP since 2002. Therefore, in future conservation of agrobiodiversity, incorporating some sustainable protection measures based in local communities such as convening seed exchange fairs, conserving traditional varieties in permanent plots, making a visual documentary of indigenous cultivation, and providing traditional agricultural products to tourists should be carefully considered and adopted.
- Published
- 2017
20. Swidden agriculture and sloping land conversion in China's Dulong Valley: impact and adaptation
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Shen ShiCai Shen ShiCai, Li DiYu Li DiYu, Zhang FuDou Zhang FuDou, Xu GaoFeng Xu GaoFeng, A. Wilkes, Yin Lun Yin Lun, and Jin GuiMei Jin GuiMei
- Published
- 2017
- Full Text
- View/download PDF
21. Designing Cropping Systems to Improve the Management of the Invasive Weed Phalaris minor Retz
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Shaosong Yang, Jun Li, Liyao Dong, Yun Zhang, Yuan Gao, Gaofeng Xu, Guimei Jin, Fudou Zhang, Shicai Shen, and David R. Clements
- Subjects
0106 biological sciences ,Stomatal conductance ,Specific leaf area ,seed germination ,01 natural sciences ,Phalaris minor ,parasitic diseases ,ecological control ,biology ,reproductive characteristics ,fungi ,seed dormancy ,Seed dormancy ,food and beverages ,Sowing ,cropping systems ,04 agricultural and veterinary sciences ,biology.organism_classification ,Weed control ,Agronomy ,Germination ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Weed ,Agronomy and Crop Science ,010606 plant biology & botany - Abstract
Because cropping systems can greatly affect the establishment and spread of alien species populations, the design of cropping systems to control invasive weeds is an important approach for invasive species management in agro-ecosystems to avoid excessive increases in other control measures such as herbicides. The annual weed Phalaris minor Retz. (P. minor) is one of the most troublesome invasive weed species of winter crops in Yunnan Province, China, but the development of cropping systems for ecological control of this weed have received limited research attention. Here, we studied seed dormancy, germination characteristics and reproductive responses of P. minor to various cropping systems to show how cropping systems could be better designed to control P. minor in China. Our research showed that cropping systems significantly affected seed dormancy in submerged paddy fields. Phalaris minor seed remained dormant and the germination rates (less than 10%) were significantly lower (p <, 0.05) than in maize fields and dry, bare soil conditions. Wheat, faba bean and rapeseed crops had no significant influence (p <, 0.05) on the seed germination rate of P. minor, but increasing soil depth significantly decreased (p <, 0.05) the germination rate and germination index of this weed. Total biomass, spike biomass, spike number and seed number of P. minor were significantly reduced (p <, 0.05) with increasing proportions of the three crops (wheat, faba bean and rapeseed), with rapeseed having the strongest inhibition effects among the three crops. The reproductive allocation and reproductive investment of P. minor were also significantly reduced (p <, 0.05) in mixed culture with wheat and rapeseed. With increasing proportions of wheat or rapeseed, the specific leaf area of P. minor significantly increased (p <, 0.05), but the reverse was true for leaf area and specific leaf weight. Moreover, the net photosynthetic rate, stomatal conductance and transpiration rate for P. minor also decreased significantly (p <, 0.05) when grown with wheat or rapeseed. These results suggest that optimal cropping systems design could involve planting rapeseed in conjunction with deep plowing and planting rice (continuous submergence underwater) in summer. Such a system could reduce the field populations and seed bank of P. minor, thus providing a sustainable and environmentally friendly means of suppressing P. minor.
- Published
- 2019
- Full Text
- View/download PDF
22. Suppression of reproductive characteristics of the invasive plant Mikania micrantha by sweet potato competition
- Author
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Hisashi Kato-Noguchi, Fudou Zhang, Gaofeng Xu, Shufang Liu, Shicai Shen, Yanxian Yang, Guimei Jin, David R. Clements, and Aidong Chen
- Subjects
0106 biological sciences ,0301 basic medicine ,Biological pest control ,Mikania ,Ipomoea ,010603 evolutionary biology ,01 natural sciences ,Crop ,03 medical and health sciences ,Environmental Science(all) ,Mikania micrantha ,Reproductive suppression ,Animals ,Ipomoea batatas ,Ecology, Evolution, Behavior and Systematics ,General Environmental Science ,biology ,Competition ,Phenology ,Diptera ,Reproduction ,fungi ,food and beverages ,Bees ,biology.organism_classification ,030104 developmental biology ,Agronomy ,Germination ,Seedling ,Sweet potato ,Biological control ,Flowering and fruiting phenology ,Research Article - Abstract
Background As a means of biologically controlling Mikania micrantha H.B.K. in Yunnan, China, the influence of sweet potato [Ipomoea batatas (L.) Lam.] on its reproductive characteristics was studied. The trial utilized a de Wit replacement series incorporating six ratios of sweet potato and M. micrantha plants in 25 m2 plots over 2 years. Results Budding of M. micrantha occurred at the end of September; flowering and fruiting occurred from October to February. Flowering phenology of M. micrantha was delayed (P
- Published
- 2015
23. Suppression of the invasive plant mile-a-minute (Mikania micrantha) by local crop sweet potato (Ipomoea batatas) by means of higher growth rate and competition for soil nutrients
- Author
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Fudou Zhang, Gaofeng Xu, Shicai Shen, Aidong Chen, Guimei Jin, David R. Clements, and Hisashi Kato-Noguchi
- Subjects
Crops, Agricultural ,Soil nutrients ,China ,media_common.quotation_subject ,Plant Weeds ,Biology ,Ipomoea ,Competition (biology) ,Soil ,Environmental Science(all) ,Soil pH ,Biomass ,Ipomoea batatas ,Mikania ,Mikania micrantha ,Ecology, Evolution, Behavior and Systematics ,General Environmental Science ,media_common ,Crop yield ,Soil organic matter ,fungi ,food and beverages ,Agriculture ,Mile-a-minute ,Interspecific competition ,biology.organism_classification ,Competition interactions ,Agronomy ,Sweet potato ,Biological control ,Monoculture ,Introduced Species ,Research Article - Abstract
Background There are a variety of ways of increasing crop diversity to increase agricultural sustainability and in turn having a positive influence on nearby natural ecosystems. Competitive crops may provide potent management tools against invasive plants. To elucidate the competitive mechanisms between a sweet potato crop (Ipomoea batatas) and an invasive plant, mile-a-minute (Mikania micrantha), field experiments were carried out in Longchuan County of Yunnan Province, Southwest China, utilizing a de Wit replacement series. The trial incorporated seven ratios of sweet potato and mile-a-minute plants in 25 m2 plots. Results In monoculture, the total biomass, biomass of adventitious root, leafstalk length, and leaf area of sweet potato were all higher than those of mile-a-minute, and in mixed culture the plant height, branch, leaf, stem node, adventitious root, flowering and biomass of mile-a-minute were suppressed significantly (P
- Published
- 2015
- Full Text
- View/download PDF
24. Ipomoea batatas (sweet potato), a promising replacement control crop for the invasive alien plant Ageratina adenophora (Asteraceae) in China.
- Author
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Shicai Shen, Gaofeng Xu, Diyu Li, Guimei Jin, Shufang Liu, Clements, David Roy, Yanxian Yang, Jia Rao, Aidong Chen, Fudou Zhang, and Xiaocheng Zhu
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SWEET potatoes ,INTRODUCED plants ,SOIL seed banks ,INVASIVE plants ,LEAF area ,COMPETITION (Biology) - Abstract
Ipomoea batatas (L.) Lam has been recognized as a very competitive crop against certain farming weeds, but more information is required to support its potential field application. The current study utilized a de Wit replacement series incorporating five ratios of I. batatas and Ageratina adenophora (Spreng.) R. M. King and H. Rob plants in 9 m2 plots in 2018. In monoculture, the main stem length, leafstalk length, leaf area, and biomass of I. batatas were significantly higher than those of A. adenophora. In mixed culture, the plant height, branch, leaf, and biomass of A. adenophora were significantly suppressed (P < 0.05) by I. batatas. The relative yield (RY) of I. batatas was significantly higher than 1.0, and the RY of A. adenophora was significantly less than 1.0 (P < 0.05) in mixed culture, indicating that the intraspecific competition was higher than interspecific competition for I. batatas, but the intraspecific competition was less than interspecific competition for A. adenophora. The competitive balance index of I. batatas demonstrated a higher competitive ability than A. adenophora. The net photosynthetic rate (Pn) of I. batatas and A. adenophora increased gradually from July to September, and then decreased from September to November in all treatments. The Pn of I. batatas was higher than that of A. adenophora in July and August, less than that of A. adenophora from September to November in monoculture, and the Pn of A. adenophora was significantly suppressed (P < 0.05) with increasing proportions of I. batatas in mixed culture after August. The activities of antioxidant enzymes superoxide dismutase, peroxidase and catalase for A. adenophora were significantly reduced (P < 0.05) with increasing proportions of I. batatas in mixed culture. Our results showed that plant growth of A. adenophora was significantly suppressed by I. batatas competition due to certain morphological and physiological advantages of I. batatas. Therefore, I. batatas is a promising replacement control candidate for managing the infestations of A. adenophora, reducing the soil seed bank and seedlings of A. adenophora. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
25. Method to remove the interference in reflected wave of passive radar based on the improved FastICA
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Yinhe Wang, Guibin Jin, Shuzhao Wang, and Guimei Jin
- Subjects
Signal-to-noise ratio ,Interference (communication) ,Acoustics ,FastICA ,Electronic engineering ,Filter (signal processing) ,Blind signal separation ,Independent component analysis ,Frequency modulation ,Mathematics ,Passive radar - Abstract
In allusion to the complexion that the serious harm to passive radar which is based on FM (the resource of frequency modulation) by the multiplex interference in identical frequency, and the average method such as filter couldn't remove it, a novel method to eliminate the interference based on the improved FastICA (fixed point Independent Component Analysis) is presented. This method pick-up the pure signal by blind source separation which is depended on the improved FastICA and eliminate the multiplex interference in identical frequency. The result of blind source separation for the data show that the improved FastICA is a effective method in eliminating the interference. Therefore, this method can improve the precision of orientation for passive radar which is based on the FM.
- Published
- 2009
- Full Text
- View/download PDF
26. Effects of sweet potato (Ipomoea batas) cultivation on the community composition and diversity of weeds in arid fields
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Shicai, Shen, primary, Gaofeng, Xu, additional, Fudou, Zhang, additional, Guimei, Jin, additional, and Yuhua, Zhang, additional
- Published
- 2014
- Full Text
- View/download PDF
27. Suppression of reproductive characteristics of the invasive plant Mikania micrantha by sweet potato competition.
- Author
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Shicai Shen, Gaofeng Xu, Clements, David Roy, Guimei Jin, Shufang Liu, Yanxian Yang, Aidong Chen, Fudou Zhang, and Hisashi Kato-Noguchi
- Subjects
SWEET potatoes ,MIKANIA ,ANGIOSPERM genetics ,PLANT succession - Abstract
Background: As a means of biologically controlling Mikania micrantha H.B.K. in Yunnan, China, the influence of sweet potato [Ipomoea batatas (L.) Lam.] on its reproductive characteristics was studied. The trial utilized a de Wit replacement series incorporating six ratios of sweet potato and M. micrantha plants in 25 m2 plots over 2 years. Results: Budding of M. micrantha occurred at the end of September; flowering and fruiting occurred from October to February. Flowering phenology of M. micrantha was delayed (P < 0.05), duration of flowering and fruiting was reduced (P < 0.05) and duration of bud formation was increased (P < 0.05) with increasing proportions of sweet potato. Reproductive allocation, reproductive investment and reproductive index of M. micrantha were significantly reduced (P < 0.05) with increasing sweet potato densities. Apidae bees, and Calliphoridae or Syrphidae flies were the most abundant visitors to M. micrantha flowers. Overall flower visits decreased (P < 0.05) as sweet potato increased. Thus the mechanism by which sweet potato suppressed sexual reproduction in M. micrantha was essentially two-fold: causing a delay in flowering phenology and reducing pollinator visits. The number, biomass, length, set rate, germination rate, and 1000-grain dry weight of M. micrantha seeds were suppressed (P < 0.05) by sweet potato competition. With proportional increases in sweet potato, sexual and asexual seedling populations of M. micrantha were significantly reduced (P < 0.05). The mortality of both seedling types increased (P < 0.05) with proportional increases in sweet potato. Conclusions: These results suggest that sweet potato significantly suppresses the reproductive ability of the invasive species M. micrantha, and is a promising alternative to traditional biological control and other methods of control. Planting sweet potato in conjunction with other control methods could provide a comprehensive strategy for managing M. micrantha. The scenario of controlling M. micrantha by utilizing a crop with a similar growth form may provide a useful model for similar management strategies in other systems. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
28. Suppression of the invasive plant mile-a-minute (Mikania micrantha) by local crop sweet potato (Ipomoea batatas) by means of higher growth rate and competition for soil nutrients.
- Author
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Shicai Shen, Gaofeng Xu, Clements, David Roy, Guimei Jin, Aidong Chen, Fudou Zhang, and Hisashi Kato-Noguchi
- Subjects
INVASIVE plants ,MIKANIA ,SWEET potatoes ,SUSTAINABILITY - Abstract
Background: There are a variety of ways of increasing crop diversity to increase agricultural sustainability and in turn having a positive influence on nearby natural ecosystems. Competitive crops may provide potent management tools against invasive plants. To elucidate the competitive mechanisms between a sweet potato crop (Ipomoea batatas) and an invasive plant, mile-a-minute (Mikania micrantha), field experiments were carried out in Longchuan County of Yunnan Province, Southwest China, utilizing a de Wit replacement series. The trial incorporated seven ratios of sweet potato and mile-a-minute plants in 25 m
2 plots. Results: In monoculture, the total biomass, biomass of adventitious root, leafstalk length, and leaf area of sweet potato were all higher than those of mile-a-minute, and in mixed culture the plant height, branch, leaf, stem node, adventitious root, flowering and biomass of mile-a-minute were suppressed significantly (P < 0.05). The relative yield (RY) of mile-a-minute and sweet potato was less than 1.0 in mixed culture, indicating that intraspecific competition was less than interspecific competition. The competitive balance index of sweet potato demonstrated a higher competitive ability than mile-a-minute. Except pH, other soil nutrient contents of initial soil (CK) were significantly higher than those of seven treatments. The concentrations of soil organic matter, total N, total K, available N, available P, available K, exchange Ca, exchange Mg, available Mn, and available B were significantly greater (P < 0.05) in mile-a-minute monoculture soil than in sweet potato monoculture soil, and were reduced by the competition of sweet potato in the mixture. Conclusions: Evidently sweet potato has a competitive advantage in terms of plant growth characteristics and greater absorption of soil nutrients. Thus, planting sweet potato is a promising technique for reducing infestations of mile-a-minute, providing weed management benefits and economic returns from harvest of sweet potatoes. This study also shows the potential value of replacement control methods which may apply to other crop-weed systems or invaded natural ecosystems. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
29. Method to remove the interference in reflected wave of passive radar based on the improved FastICA.
- Author
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Shuzhao Wang, Guibin Jin, Guimei Jin, and Yinhe Wang
- Published
- 2009
- Full Text
- View/download PDF
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