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Ma Q.-G.,Chinese Academy of Forestry | Wang H.,Chinese Academy of Forestry | Wang H.,Huazhong Agricultural University | Pan G.,Research Institute of Plateau Ecology | Pei D.,Chinese Academy of Forestry
Beijing Linye Daxue Xuebao/Journal of Beijing Forestry University | Year: 2011

In order to deeply understand the genetic background and the genetic diversity of Tibet walnut germplasm resources, FISH-AFLP was conducted using 9 EcoR I+3/Mse I+3 primer combinations to analyse 11 walnut (Juglans regia L.) advanced trees from Tibet at genomic DNA level. Totally 1103 AFLP fragments were obtained, in which 1076 were polymorphic and the average percentage of polymorphic bands (ppb) was 97.67%. The value of effective number of alleles (Ne) ranged from 1.00 to 1.99 with an average of 1.48 ± 0.04; Nei's gene diversity (H) ranged from 0.00 to 0.49 with an average of 0.29 ± 0.02 and Shannon's information index (I) ranged from 0.00 to 0.69 with an average of 0.44 ± 0.02. The genetic diversity and sibship among walnut advanced trees in Tibet were investigated and their fingerprintings were established in the research. Source

Wang L.,CAS Kunming Institute of Botany | Meng L.,Yunnan Normal University | Luo J.,Research Institute of Plateau Ecology
Scientific World Journal | Year: 2015

Generally, plant reproductive success might be affected negatively by florivory, and the effects may vary depending on the timing and intensity of florivory. To clarify the impacts of florivory by the sawfly larvae (Tenthredinidae) on seed production of Halenia elliptica D. Don, we simulated florivory by removing different proportion of flowers at three reproductive stages in this alpine herb and then examined the seed number per fruit, the seed weight, and the seed mass per fruit of the remaining flowers. Seed number per fruit reduced significantly when flowers were removed at flowering and fruiting stages or when 15% and 60% of flowers were removed. However, seed weight increased significantly after flowers were removed, independent of treatments of reproductive stage and proportion. There was a similar seed mass per fruit between the plants subjected to simulation of florivory and control. The results indicated that florivory modulated the seed number-seed weight relationship in this alpine species. Our study suggested that selective seed abortion and resource reallocation within fruits may ensure fewer but larger seeds, which were expected to be adaptive in the harsh environments. © 2015 Linlin Wang et al. Source

Meng L.-H.,Yunnan Normal University | Wang Y.,CAS Kunming Institute of Botany | Luo J.,Research Institute of Plateau Ecology | Liu C.-Y.,Yunnan Normal University | And 2 more authors.
Plant Ecology and Evolution | Year: 2012

Background and aims - Megacodon stylophorus (C.B.Clarke) Harry Sm. is an endangered herb native to the East-Himalaya and the Hengduan Mountains, south-west China. We studied reproductive ecology of this species to explore the factors that are critical for its survival and conservation. Methods - We conducted breeding system experiments during 2008 and 2009 in two populations located in the Hengduan Mountains. Key results - The flowers are protandrous and herkogamous, and thus insects are necessary for pollination and seed production. Bumblebees were observed to be the most frequent visitors, and their visitation rates were lower at the higher altitude. Seed production in both populations fluctuated annually, possibly due to pollen limitation, which occurred in both populations in the two years. Conclusions - The pollination level is only marginally responsible for the rarity of this alpine species. We suggest that in situ conservation measures should be given the highest priority at present, considering the strong genetic differentiation among populations. © 2012 National Botanic Garden of Belgium and Royal Botanical Society of Belgium. Source

Meng L.-H.,Yunnan Normal University | Wang Y.,CAS Kunming Institute of Botany | Luo J.,Research Institute of Plateau Ecology | Yang Y.-P.,CAS Kunming Institute of Botany | Duan Y.-W.,CAS Kunming Institute of Botany
Polish Journal of Ecology | Year: 2014

Given the finite resources of seed production, a trade-off between seed weight and number was expected. However, it still remains unclear how the seed weight-number trade-off changes if there are some mechanisms to enhance resource acquirements during the fruit developments. Sinopodophyllum hexandrum presents furled leaves in flowering time but unfurled leaves in fruiting time, which is considered to enhance the photosynthates to fruit development. To determine the relationship between seed weight and number of S. hexandrum, we examined the altitudinal variations and the relationship between seed weight and number in the fruits from 27 populations of in 2009 and 2010. Our results showed that, along the altitudinal gradient, seed weight decreased significantly but seed number increased insignificantly, indicating that the selective pressure on seed production might come from seed dispersal in high altitude populations. There was no significant relationship between seed weight and number in most populations, but an inverse relationship was found between seed weight and number when the data from all populations were pooled, indicating the seed weight-number trade-off and resource limitation of seed production in S. hexandrum on species level. We suggested that the two unfurled leaves of S. hexandrum might contribute to the resources allocated to the fruit development via enhancing photosynthates, which might mask the seed weight-number trade-off on population level to some degree. © 2014, Polish Academy of Sciences. All rights reserved. Source

Ma H.-P.,Research Institute of Plateau Ecology | Guo Q.-Q.,Research Institute of Plateau Ecology | Liu H.-M.,Tibet Agricultural and Animal Husbandry College | Qian D.-F.,Tibet Agricultural and Animal Husbandry College
Forest Research | Year: 2013

In order to explore the effects of total nutrient on surface soil (0~20cm), the alpine shrub, Rhododendron forest, Abies georgei var. smithii forest and Picea likiangensis var. linzhiensis forest were selected as experimental sites, the soil organic carbon (SOC), total nitrogen (TN), microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), readily oxidizable organic carbon (ROC), and particulate organic carbon (POC) were studied at different altitudes. The results showed that compared with lower-elevation vegetation types, the higher ones were found significantly higher in their SOC content and proportion. The SOC and TN contents were increasing along the elevation gradient in Sejila Mountain. The surface SOC of alpine shrub was the largest (77.167) and P. likiangensis var. linzhiensis forest the smallest(22.351). The TN of alpine shrub was the largest(2.430) and P. likiangensis var. linzhiensis forest the smallest(0.830). The surface C/N ratio of A. georgei var. smithii forest was the largest(43.57) and P. likiangensis var. linzhiensis forest the smallest(26.93). The elevation and wood stand had a significant impact on MBC and MBN. With lower altitude, the ratio of the POC in TOC decreased from 44.81% to 19.32%, the ratio of ROC in TOC decreased from 41.72% to 7.07%. The POC and ROC of different wood lands were significantly related to SOC. And the active SOC was significantly related to total SOC. The relationship between soil microbial biomass and readily oxidizable organic carbon was significant(p < 0.05). Source

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