Brazil nut conservation through shifting cultivation     

Paulo Marcelo Paiva  Marcelino Carneiro Guedes  Claudia Funi 《Forest Ecology and Management》2011,261(3):508-514

The regeneration of Brazil nut trees depends on tree-fall gaps in the forest. However, shifting cultivation fallows also create comparable biotic and abiotic opportunities for the dispersion and establishment of this gap-loving species. At the same time, the ability of Brazil nut trees to resprout enables fallow individuals to survive successive slash-and-burn cycles. Recognizing the importance of shifting cultivation for the food security of forest dwellers, we investigated whether the high level of Brazil nut regeneration found in cultivation fallows could be explained by the resprouting capability of Brazil nut trees, the number of cultivation cycles, past agricultural use and distance to the nearest conspecific productive adults. We found that the Brazil nut tree population density increased from 8.86 trees ha⁻¹ to 13.69 trees ha⁻¹ and 27.09 trees ha⁻¹ at sites after one, two and three or more shifting cultivation cycles, respectively. As a consequence of resprouting, after a certain number of shifting cultivation cycles, the fallows become dominated by Brazil nut trees, and the landholders may decide to preserve them and to exclude enriched sites from future agricultural use. Protected for their extractive value, the secondary forests spontaneously enriched with Brazil nut trees are allowed to develop into nut-producing forests that have reduced chances of conversion into crops or pastures, thus reversing the classical process of Amazon forest degradation.  相似文献   

Molecular and pedigree analysis applied to conservation of animal genetic resources: the case of Brazilian Somali hair sheep     

Paiva SR  Facó O  Faria DA  Lacerda T  Barretto GB  Carneiro PL  Lobo RN  McManus C 《Tropical animal health and production》2011,43(7):1449-1457

The first registers of Somali sheep in Brazil are from the beginning of the 1900s. This breed, adapted to the dry climate and scarce food supply, is restricted in the northeast region of the country. Molecular marker technologies, especially those based on genotyping microsatellite and mtDNA loci, can be used in conjunction with breeding (pedigree analysis) and consequently the maintenance of genetic variation in herds. Animals from the Brazilian Somali Conservation Nuclei from Embrapa Sheep and Goats in Ceará State were used to validate genetic monitoring by traditional pedigree methods and molecular markers. Nineteen microsatellite markers and 404 base pairs from the control region of mtDNA were used. For total herd diversity, an average 5.32 alleles were found, with expected heterozygosity of 0.5896, observed heterozygosity of 0.6451, 0.4126 for molecular coancestrality, and coefficient of inbreeding (F _IS) was −0.095. Comparing molecular coancestrality means over the years, there was a consistent increase in this parameter within the herd, increasing from 0.4157 to 0.4769 in 2 years (approx. 12% variation). Sixteen mtDNA haplotypes were identified. Inbreeding and other estimates from genealogical analyses confirm the results from molecular markers. From these results, it is possible to state that microsatellites are useful tools in genetic management of herds, especially when routine herd recording is not carried out, or there were gaps in recent generations. As well as pedigree control, genetic diversity can be optimized. Based on the results, and despite herd recording in the herd of Brazilian Somali of Embrapa Sheep and Goats, additional management measures need to be carried out in this herd to reduce inbreeding and optimize genetic variation.  相似文献   

Genetic diversity and population structure in Jatropha (Jatropha curcas L.) based on molecular markers     

de Souza Carneiro  Adriana  dos Santos  Adriano  Laviola  Bruno Galv&#;as  Teodoro  Larissa Pereira Ribeiro  Teodoro  Paulo Eduardo  Rodrigues  Erina Vit&#;rio 《Genetic Resources and Crop Evolution》2022,69(1):245-254

Genetic Resources and Crop Evolution - Jatropha (Jatropha curcas L.) is an oleaginous potential, howetever, some studies report that there is low genetic diversity in Brazilian genotypes....  相似文献   

Orchid bees respond to landscape composition differently depending on the multiscale approach     

da Silva Carneiro  Lázaro  Ribeiro  Milton Cezar  Aguiar  Willian Moura de  de Fátima Priante  Camila  Frantine-Silva  Wilson  Gaglianone  Maria Cristina 《Landscape Ecology》2022,37(6):1587-1601

Landscape Ecology - Multiscale approaches are essential for understanding ecological processes and detecting the scale of effect. However, nested multiscale approaches retain the effect of the...  相似文献   

Genetic diversity of Meloidogyne spp. from rice and identification of multiresistant sources in Oryza spp. accessions     

Vanessa S. Mattos  Raycenne R. Leite  Marcilene F.A. Santos  Cesar B. Gomes  Philippe Castagnone-Sereno  Juvenil E. Cares  Regina M.D.G. Carneiro 《Plant pathology》2021,70(9):2217-2228

Recently a Meloidogyne species complex was detected parasitizing and causing damage to irrigated rice in southern Brazil, highlighting the need to study the genetic diversity of these species and their pathogenicity to Oryza spp. in order to select genotypes of rice with multiple resistance. This study compared the genetic diversity of Brazilian Meloidogyne spp. isolates from irrigated rice and evaluated the reaction of four wild accessions of Oryza species (O. glumaepatula, O. longistaminata, O. grandiglumis, and O. alta) and two cultivated species, O. glaberrima and O. sativa (control) to M. ottersoni, M. oryzae, and two variants of M. graminicola (Est G2 and Est G3). Genetic variability was assessed using RAPD and AFLP markers. M. graminicola and M. ottersoni showed high intraspecific variability: 83.76% and 41.14%, respectively. Cluster analysis showed a clear separation among rice root-knot nematodes (RKNs) into subclades according to their esterase phenotypes with 100% bootstrap. For rice resistance screening, plants were inoculated with 5,000 eggs, and the nematode reproduction factor evaluated 90–120 days postinoculation. O. glumaepatula, an American wild species, was highly resistant or resistant to all rice RKNs tested and is a valuable source of multiple resistance. Overall, the other rice species also showed different levels of resistance. Conversely, O. longistaminata exhibited low levels of resistance. M. graminicola Est G3 was the most aggressive isolate. Sources of resistance against RKN in wild Oryza genotypes, especially in an AA genome like O. glumaepatula, may be of great interest for future breeding programmes in cultivated rice.  相似文献   

Development and agronomic performance of common bean lines simultaneously resistant to anthracnose, angular leaf spot and rust   总被引：1，自引：0，他引：1  

V. A. Ragagnin    T. L. P. O. de Souza  D. A. Sanglard    K. M. A. Arruda    M. R. Costa    A. L. Alzate-Marin  J. E. de S.  Carneiro  M. A. Moreira    E. G. de Barros 《Plant Breeding》2009,128(2):156-163

The common bean is affected by several pathogens that can cause severe yield losses. Here we report the introgression of resistance genes to anthracnose, angular leaf spot and rust in the 'carioca-type' bean cultivar 'Rudá'. Initially, four backcross (BC) lines were obtained using 'TO', 'AB 136', 'Ouro Negro' and 'AND 277' as donor parents. Molecular fingerprinting was used to select the lines genetically closer to the recurrent parent. The relative genetic distances between 'Rudá' and the BC lines varied between 0.0% and 1.99%. The BC lines were intercrossed and molecular markers linked to the resistance genes were used to identify the plants containing the genes of interest. These plants were selfed to obtain the F₂, F₃ and F₄ plants which were selected based on the presence of the molecular markers mentioned and resistance was confirmed in the F₄ generation by inoculation. Four F_4:7 pyramid lines with all the resistance genes showed resistance spectra equivalent to those of their respective donor parents. Yield tests showed that these lines are as productive as the best 'carioca-type' cultivars.  相似文献   

High levels of pollen dispersal detected through paternity analysis from a continuous Symphonia globulifera population in the Brazilian Amazon     

Francimary da Silva Carneiro  Bernd Degen  Milton Kanashiro  Andre Eduardo Biscaia de Lacerda  Alexandre Magno Sebbenn   《Forest Ecology and Management》2009,258(7):1260-1266

In this study, six highly polymorphic microsatellite loci and a categorical paternity analysis approach were used to investigate the contemporary pollen gene flow in the neotropical tree species Symphonia globulifera. Data for this study were taken from a 500 ha experimental plot in a dense terra firme forest in the Eastern Brazilian Amazon and included the mapping and genotyping of 161 reproductive trees, representing more than 90% of all adult trees, and the collection of 748 open-pollinated seeds from 56 seed-trees over two field seasons (2002 and 2003). High levels of pollen immigration from outside of the study plot were detected in both sampled seed-years (≥49%) suggesting long distance pollen gene flow. Low levels of self-fertilization were also detected (≤2%). The analysis showed long distance pollen dispersal occurred within the study area in both 2002 (δ = 907 ± 652 m SD) and 2003 (δ = 963 ± 542 m SD). Patterns of pollen dispersal distance within the plot were also found to be shorter than the distances between potential male parents and seed-trees. This result indicates that the distance between trees does not explain the identified pollen dispersal pattern. Our results support the hypothesis that animal pollinated species occurring in low-density populations can disperse pollen in long distances, despite the very dense nature of the forest.  相似文献   

Genetic diversity,population structure,and correlations between locally adapted zebu and taurine breeds in Brazil using SNP markers     

Bárbara Machado Campos  Adriana Santana do Carmo  Andrea Alves do Egito  Arthur Silva da Mariante  Maria Socorro Muaés do Albuquerque  João José Simoni de Gouveia  Carlos Henrique Mendes Malhado  Lucas Lima Verardo  Marcos Vinícius Gualberto Barbosa da Silva  Paulo Luiz Souza Carneiro 《Tropical animal health and production》2017,49(8):1677-1684

Genetic diversity is one of the most important issues in studies on conservation of cattle breeds and endangered species. The objective of this study was to estimate the levels of genetic differentiation between locally adapted taurine (Bos taurus taurus) and zebu (Bos taurus indicus) breeds in Brazil, which were genotyped for more than 777,000 SNPs. The fixation index (F _ST), principal component analysis (PCA), and Bayesian clustering were estimated. The F _ST highlighted genetic differentiation between taurine and zebu breeds. The taurine lines, Caracu and Caracu Caldeano, had significant genetic differentiation (F _ST close to 5%) despite their recent selection for different uses (meat and milk). This genetic variability can be used for conservation of locally adapted animals, as well as for breeding programs on zebu breeds. Introgression of zebu in locally adapted breeds was identified, especially in Curraleiro Pé-Duro breed. The Gyr breed, however, had low breed purity at genomic level due to its very heterogeneous mixing pattern.  相似文献   

Effects of live feed containing Panagrellus redivivus and water depth on growth of Betta splendens larvae          下载免费PDF全文

Márcia Valéria Silva do Couto  Natalino da Costa Sousa  Higo Andrade Abe  Joel Artur Rodrigues Dias  Juliana Oliveira Meneses  Peterson Emmanuel Guimarães Paixão  Fernanda dos Santos Cunha  Fabrício Menezes Ramos  Alexandre Nizio Maria  Paulo Cesar Falanghe Carneiro  Rodrigo Yudi Fujimoto 《Aquaculture Research》2018,49(8):2671-2675

Panagrellus redivivus is a nematode with a high protein content and low‐cost production. It is successfully used in the larviculture of shrimp, however, it has not yet been evaluated as feed for Betta splendens larvae. Thus, the objective of this study was to evaluate P. redivivus as feed for betta larvae maintained at different depths of water. The experiment was based on a completely randomized 3 × 2 factorial design, represented by two feed types and one alternating feeding regime plus two water depths (2.5 and 5.0 cm). The Artemia feed promoted the highest weight gain, followed by the alternating feeding regime. The single use of the nematode as live feed produced the poorest weight gain. The water depth and the feeding method influenced the specific growth rate (SGR). At a depth of 2.5 cm, the alternating feeding promoted similar SGR compared to fish fed with Artemia only. Furthermore, at the greater water depth an improvement in SGR was observed in fish fed Artemia only, but the similarity to alternating feeding regime remains. Thus, the inclusion of nematode is an appropriate and lower cost feed strategy for the betta larviculture independent of water depths.  相似文献   

New Insights on the Terpenome of the Red Seaweed Laurencia dendroidea (Florideophyceae,Rhodophyta)     

Louisi Souza de Oliveira  Diogo Antonio Tschoeke  Aline Santos de Oliveira  Lilian Jorge Hill  Wladimir Costa Paradas  Leonardo Tavares Salgado  Cristiane Carneiro Thompson  Renato Crespo Pereira  Fabiano L. Thompson 《Marine drugs》2015,13(2):879-902

The red seaweeds belonging to the genus Laurencia are well known as halogenated secondary metabolites producers, mainly terpenoids and acetogennins. Several of these chemicals exhibit important ecological roles and biotechnological applications. However, knowledge regarding the genes involved in the biosynthesis of these compounds is still very limited. We detected 20 different genes involved in the biosynthesis of terpenoid precursors, and 21 different genes coding for terpene synthases that are responsible for the chemical modifications of the terpenoid precursors, resulting in a high diversity of carbon chemical skeletons. In addition, we demonstrate through molecular and cytochemical approaches the occurrence of the mevalonate pathway involved in the biosynthesis of terpenes in L. dendroidea. This is the first report on terpene synthase genes in seaweeds, enabling further studies on possible heterologous biosynthesis of terpenes from L. dendroidea exhibiting ecological or biotechnological interest.  相似文献