Yunnan Institute of Tropical Crops

Jinghong, China

Yunnan Institute of Tropical Crops

Jinghong, China
Time filter
Source Type

Zu T.,Jiangnan University | He M.,Yunnan Institute of Tropical Crops | Zhang L.,Jiangnan University
Journal of the Chinese Cereals and Oils Association | Year: 2013

The aqueous enzymatic extraction of oil from rubber seed was studied in this paper. The effects of pretreatment methods, enzyme type and dosage and processing technology on the yield of rubber seed oil were investigated by the single factor test. Then optimal processing parameters were established by the orthogonal test on the basis of single factor test and were described as follow: the ratio of solid to liquid was 1:4, reacting temperature was 50°C and the reaction lasted 8 h, cellulase and β-glucanase were selected as working enzyme and the dosage was 0.5 g/100 g solution, the acidity of the solution was adjusted to pH 5.0. The solution was then centrifugated at 5000 r/min for 30 min continued by demulsification which was boiling water bath heating 10 min followed by 6000 r/min 10 min centrifugation. Under these optimal conditions, the yield of rubber seed oil was 89.3%. The rubber seed oil obtained by aqueous enzymatic method was transparent, pale yellow, and fragrance.

Tian Y.,Yunnan Institute of Tropical Crops | Lei Y.,CAS Xishuangbanna Tropical Botanical Garden | Zheng Y.,CAS Xishuangbanna Tropical Botanical Garden | Cai Z.,CAS Xishuangbanna Tropical Botanical Garden
Acta Physiologiae Plantarum | Year: 2013

The objective of this study was to investigate the effects of arbuscular mycorrhizal fungus (AMF) inoculation on plant growth and drought tolerance in seedlings of a promising oilseed crop, Sacha Inchi (Plukenetia volubilis L.), under well-watered or drought conditions. AMF inoculation was applied in four treatments: without AMF inoculation, Glomus versiforme, Paraglomus occultum, or combination of both microorganism inoculations. The results showed that AMF colonization significantly enhanced the growth of Sacha Inchi seedlings regardless of soil water conditions, and the greatest development was reached in plants dually inoculated under well-watered conditions. G. versiforme was more efficient than P. occultum. Plants inoculated with both symbionts had significantly greater specific leaf area, leaf area ratio and root volume when compared with the uninoculated control, G. versiforme, and P. occultum treatments alone, indicating a synergistic effect in the two AMF inoculation. Photosynthetic rate and water-use efficiency were stimulated by AMF, but not stomatal conductance. Inoculation with AM fungus increased antioxidant enzymes activities including guaiacol peroxidase and catalase, thus lowering hydrogen peroxide accumulation and oxidative damage, especially under drought stress conditions. However, proline content showed little change during drought stress and AMF colonization conditions, which suggested that proline accumulation might not serve as the main compound for osmotic adjustment of the studied species. These results indicate that AMF inoculation stimulated growth and enhanced drought tolerance of Sacha Inchi seedlings, through alterations in morphological, physiological and biochemical traits. This microbial symbiosis might be an effective cultivation practice in improving the performance and development for Sacha Inchi plants. © 2012 Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków.

Tian Y.,Yunnan Institute of Tropical Crops | Yuan H.,Yunnan Institute of Tropical Crops | Xie J.,Yunnan Institute of Tropical Crops | Zheng Y.,CAS Xishuangbanna Tropical Botanical Garden
Southern Forests | Year: 2015

The rapid increase in rubber monoculture in Xishuangbanna has resulted in extensive damage to its local ecosystem. To decrease the negative effects, the concept of the ecological-economic rubber plantation (EERP) system was proposed. The EERP entails intercropping rubber plants with other economically significant plants, which would not only decrease the ecological impact of the rubber plantation, but also maintain and potentially increase its profitability compared with rubber monocultures. In order to select the appropriate species and intercropping pattern in the EERP system, we compared the photosynthetic parameters of five economically important trees (Swietenia mahagoni, Coffea arabica, Mesua ferrea, Myristica yunnanensis and Paramichelia baillonii) under four irradiance levels. The optimal irradiance intensity of C. arabica and M. yunnanensis was approximately 40%, and these species can be planted in the understory of an 8- to 15-year-old rubber forest. Adult S. mahagoni, M. ferrea and P. baillonii grow taller than the rubber trees, and their seedlings also show superior performance in 100% irradiance than in other irradiances. Thus, in an EERP, these valuable trees could be planted adjacent to rubber plantations but on sites that are economically and environmentally marginal for rubber production. © 2015 NISC (Pty) Ltd

Zhou H.-P.,CAS Xishuangbanna Tropical Botanical Garden | Zhou H.-P.,Yunnan Institute of Tropical Crops | Chen J.,CAS Xishuangbanna Tropical Botanical Garden
Journal of Ecology | Year: 2010

1. The spatial genetic structure (SGS) of a plant population is mainly determined by gene flow via seed and pollen, various natural selection pressures and spatial patterns of existing plants. However, the role of those factors in shaping SGS requires further investigation. 2. We studied the relative importance of those factors in shaping the SGS of an understorey dioecious fig species (Ficus cyrtophylla). Spatial patterns of existing individuals and microhabitat were surveyed, patterns of seed rain were investigated, seed dispersers were observed in the field, and the gene flow and SGS of a focal population were determined. 3. Three mid-sized bulbul (Pycnonotus spp.) species were the primary dispersers of Ficus cyrtophylla fruits. All the age cohorts exhibited clumped patterns with a decreasing trend from seeds to seedlings, saplings and adults. Seed rain occurred in a non-random pattern with high clumping in moderately lit microhabitats. The observed pattern suggests disperser preferences for those microhabitats resulting in higher seed deposition. 4. Seeds and pollen of F. cyrtophylla were widely dispersed (ranging from 9 m to 2.75 km and 10 m to 3 km, respectively). About two-thirds of seeds and half of the pollen grains were locally dispersed (≤ 250 m) within the focal population. 5. Significant positive autocorrelations occurred at a local scale (≤10 m) in seeds and seedlings but not in saplings and adults. The SGS pattern disappeared when we reduced the sample size of seedlings to that for the saplings, which suggests that demographic thinning effects (e.g. density-dependent predation and competition) on spatial distribution may lead to the loss of SGS through transitions from seedlings to saplings and adults. 6. Synthesis. Although F. cyrtophylla seeds and pollen were widely dispersed, the significant SGS present in seedlings probably resulted from clumped seed dispersal due to dispersers' behaviour and high seedfall beneath parent trees. The loss of SGS in sapling and adult life stages is probably caused by demographic selection effects during recruitment. Our study emphasizes the different roles of dispersal and local selection in shaping SGS of plant populations. © 2010 The Authors. Journal compilation © 2010 British Ecological Society.

Jiang S.-K.,Yunnan Institute of Tropical Crops | Zhang G.-M.,Yunnan Institute of Tropical Crops | Wu Y.,Yunnan Institute of Tropical Crops | Meng Z.-H.,Beijing Institute of Technology | Xue M.,Beijing Institute of Technology
Journal of Rubber Research | Year: 2014

In the production process of natural rubber (NR), large quantities of wastewater containing substantial amounts of L-quebrachitol are discharged. To date, published methods of extracting L-quebrachitol from wastewater are still at the laboratory stage. In this study, membrane separation technology was applied to the extraction of L-quebrachitol from wastewater and the experimental parameters were studied in order to determine optimal experimental conditions. Results show that the optimum source material for L-quebrachitol extraction was the serum collected by squeezing the latex coagulum. When this serum was passed through a microfiltration (MF) membrane and two ultrafiltration (UF) membranes, majority of the organic impurities were removed. The resulting ultrafiltrate was concentrated by a nanofiltration (NF) membrane and washed twice. Finally, a new and convenient approach for large scale extraction of L-quebrachitol is proposed combining membrane separation and crystallisation. The output achieved with this approach would be 10 kg per year under laboratory conditions with 99.20% purity. The structure of L-quebrachitol was confirmed by elementary analysis, infrared (IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, mass spectroscopy (MS) and single-crystal X-ray diffraction.

Guo G.,Yunnan Institute of Tropical Crops | Peng C.,Yunnan Agricultural University | He X.,Yunnan Agricultural University | Gong J.,Yunnan Agricultural University
Journal of Chinese Institute of Food Science and Technology | Year: 2013

Antioxidant activity of different solvent extracts of sun-dried green tea was studied in this paper. The scavenging ability of DPPH free radical, OH- free radical, superoxide anion free radical and nitrite of different solvent extracts of sun-dried green tea as well as reducing power were investigated by using rutin and ascorbic acid (vitamin C) as control. Results suggested that the different solvent extracts of sun-dried green tea had significant scavenging effects on the DPPH free radical, OH- free radical, superoxide anion free radical and nitrite, all kinds of extracts had significant reducing power. Antioxidant activity of different solvent extracts of sun-dried green tea had positive correlation with their concentrations. The scavenging effects of ethanol sedimentation segment (IC50 93.80 μg/mL), n-butanol extract (IC50 153.90 μg/mL), ethanol extract (IC50 161.20 μg/mL) on the DPPH free radical were stronger than that of rutin control at the same concentration. All kinds of extracts had significant scavenging effects on ·OH- free radical, IC50 value of different solvent extracts of sun-dried green tea was very small except chloroform extract (IC50 57.67 μg/mL) and ethanol sedimentation segment (IC50 13.10 μg/mL). The scavenging effects of ethanol sedimentation segment and water extract on superoxide anion free radical were stronger than that of VC control at the 20 μg/mL concentration and stronger other extracts at the same concentration. Acetal extract and ethanol extract had stronger ability of scavenging nitrite, but lower than that of VC control. Reducing power of water extract, ethanol sedimentation segment and acetal extract had stronger than that of rutin control at the same concentration. These results suggest that the antioxidant activity of different solvent extracts of sun-dried green tea had significant differences.

Xu R.,Yunnan Institute of Tropical Crops | Guo G.-J.,Yunnan Institute of Tropical Crops | Yang Y.,Yunnan Institute of Tropical Crops | Yuan Z.-Z.,Yunnan Institute of Tropical Crops
Modern Food Science and Technology | Year: 2013

Contents of nutritional components in Angelica keiskei were determined and evaluated including protein, crude fat, crude fiber, vitamin C, water, total ash, total sugar, total flavonoids, amino acid and mineral element. Results showed that the contents of water, protein, crude fat, total sugar, crude fiber, total ash, vitamin C and total flavonoids in angelica keiskei were 92.70%, 1.99%, 0.35%, 0.21%, 0.68%, 1.40%, 0.08 mg/g and 4.79 mg/g, respectively. Contents of fifteen amino acids,EAA/TAA ratio, and EAA/NEAA ratio were 20.01%, 43.83% and 78.02%, respectively. All kinds of human essential amino acids were found with a balanced proportion and the coefficient of amino acids was 65.10. The first limiting amino acids were Met and Cys in all human essential amino acids. The contents of phosphorus, kalium, calcium, magnesium, iron, zinc, cuprum and manganese in mineral elements were 322 mg/kg, 4210 mg/kg, 1441 mg/kg, 478 mg/kg, 38 mg/kg, 2.36 mg/kg, 1.14 mg/kg and 55.70 mg/kg, respectively. Angelica keiskei was rich in all kinds of nutritional components, which had better exploitation value.

Zhou H.,Yunnan Institute of Tropical Crops | Yue H.,Yunnan Institute of Tropical Crops | Ai X.,Yunnan Institute of Tropical Crops | Chen G.,Yunnan Institute of Tropical Crops | And 3 more authors.
Forest Ecology and Management | Year: 2015

Studying seed dispersal and the associated processes of germination, seedling establishment and survival are important for understanding plant regeneration dynamics and dispersal ability, especially for introduced plant species. Rubber trees (Hevea brasiliensis) have been introduced and cultivated in Xishuangbanna in southwest China for over 60. years. However, almost no adult rubber trees occur in natural forests in the region. In order to determine the factors preventing the expansion of rubber trees into natural forests, we investigated the seed dispersal, seed germination and seedling recruitment of rubber trees. Rubber seeds released in natural forests were frequently visited and largely handled by Rattus spp., but the rubber seeds released in rubber plantations were seldom visited or fetched by any animals, indicating that habitat type had a significant effect on the fate of rubber seeds (P<. 0.001). The majority of released rubber seeds were eaten (57.80% in 2012, N= 5795; 64.45% in 2013, N= 12,455) and only a very few seeds were cached under forest litter or soil surface (0.32% in 2012 and 0.16% in 2013). When missing seeds (about 30% of all released seeds) were omitted in the analysis, it was found that the majority of the seeds were removed within 10. m (60-90% in different years and different sites), and only few seeds were transported to more than 30. m (maximum distance was 55. m in 2012 and 67. m in 2013). Rubber seeds buried in natural forests had a lower germination rate (mean. ±. SE. = 11.67. ±. 2.11%, N= 300) compared to those in rubber plantations (mean. ±. SE. = 44.33. ±. 4.25%, N= 300) (one-way ANOVA, P<0.01). Results from our seed germination experiment and natural regeneration survey showed that rubber seedlings had a very low survival rate, both in natural forests and in rubber plantations. Poor seed dispersal, seed germination and seedling survival may explain why rubber trees do not expand into the natural forests in Xishuangbanna. The findings of this study can help to better understand the natural dispersal ability and regeneration dynamics of rubber trees, providing insights important for forest conservation planning. © 2015 Elsevier B.V.

Zhou H.-P.,Yunnan Institute of Tropical Crops | Chen G.-Y.,Yunnan Institute of Tropical Crops | Yue H.,Yunnan Institute of Tropical Crops | Cun M.,Yunnan Institute of Tropical Crops
Chinese Journal of Ecology | Year: 2014

Tagged seeds of Hevea brasiliensis were separately released in five habitats. The seed fate and seed predators were observed. The results showed that, in the pure rubber plantation and the seasonal rainforest, most seeds remained untouched in situ (>80% and >98%, respectively), while in the rubber-bamboo mixed forest and in the secondary forest seed predation was almost 100%, and in the neighboring rubber plantation it was 50%. Chi-square test indicated that the seed predation rate of the rubber-bamboo mixed forest was significantly higher than that of the pure rubber plantation and the seasonal rainforest, and it was obviously higher in the secondary forest than in the neighboring rubber plantation (P<0. 001). Most seeds were predated in situ or after removing, with a very small amount of seeds being stored. Most seeds (>80%) were transported < 10 m away. By infrared-sensor camera and feeding experiment, Rattus tanezumi and Rattus surifer were confirmed as the primary seed predators. This study indicated that seeds of H. brasiliensis mainly predated by small rodents with a high predation intensity, low storage rate and short-distance dispersal (<10 m) in Xishuangbanna introduction area. © 2014, Editorial Board of Chinese Journal of Ecology. All rights reserved.

Yunnan Institute Of Tropical Crops | Date: 2013-05-17

Provided is a method for scale extraction of quebrachitol from natural rubber industry waste water, the method comprising the following steps: coarsely filtering the natural rubber industry waste water to obtain a waste water clear liquor A; filtering the waste water clear liquor A with an ultrafiltration membrane to obtain a filtrate B; concentrating the filtrate B with a nanofiltration membrane or a reverse osmosis membrane to obtain a concentrated solution C; decolorizing and then evaporating and concentrating the concentrated solution C, to obtain a pasty concentrated solution D; cooling the pasty concentrated solution D for crystallization, and collecting the crystals to obtain a coarse product E; and purifying the coarse product E to obtain a pure quebrachitol. The technology process of the method is simple and low cost, scale production can be achieved, and the purity of the obtained product can be up to 99%.

Loading Yunnan Institute of Tropical Crops collaborators
Loading Yunnan Institute of Tropical Crops collaborators