scholarly journals Eucalypts for Tropical Rainforest (Af) climate

2021 ◽  
Vol 70 (1) ◽  
pp. 170-183
Author(s):  
Arno Brune

Abstract The equatorial region of the world includes areas of Tropical Rainforest (Af) and Tropical Monsoon (Am) climate zones, which are distinguished by high temperatures and high rainfall, but soils which are often deficient. Potential productivity of plantation forestry in this area is high, and so are the pest and disease dangers which threaten it. This paper describes the Eucalyptus and Corymbia species which are adapted to this situation and also resistant to the main diseases like leaf blights. Based on the highly adapted E. biterranea and E. deglupta and several more, hybridization combined with vegetative propagation is discussed as an excellent alternative to obtain quick gains in short rotations while maintaining wide genetic diversity in such plantations. Management remedies are given for the possible backlash of quick soil depletion.

Author(s):  
C. Montagnon ◽  
A. Mahyoub ◽  
W. Solano ◽  
F. Sheibani

AbstractWhilst it is established that almost all cultivated coffee (Coffea arabica L.) varieties originated in Yemen after some coffee seeds were introduced into Yemen from neighboring Ethiopia, the actual coffee genetic diversity in Yemen and its significance to the coffee world had never been explored. We observed five genetic clusters. The first cluster, which we named the Ethiopian-Only (EO) cluster, was made up exclusively of the Ethiopian accessions. This cluster was clearly separated from the Yemen and cultivated varieties clusters, hence confirming the genetic distance between wild Ethiopian accessions and coffee cultivated varieties around the world. The second cluster, which we named the SL-17 cluster, was a small cluster of cultivated worldwide varieties and included no Yemen samples. Two other clusters were made up of worldwide varieties and Yemen samples. We named these the Yemen Typica-Bourbon cluster and the Yemen SL-34 cluster. Finally, we observed one cluster that was unique to Yemen and was not related to any known cultivated varieties and not even to any known Ethiopian accession: we name this cluster the New-Yemen cluster. We discuss the consequences of these findings and their potential to pave the way for further comprehensive genetic improvement projects for the identification of major resilience/adaptation and cup quality genes that have been shaped through the domestication process of C. arabica.


2009 ◽  
Vol 15 (1) ◽  
pp. 23-28 ◽  
Author(s):  
Katarzyna Kubiak

Genetic diversity ofAvena strigosaSchreb. ecotypes on the basis of isoenzyme markersGenetic diversity was analyzed in 19 ecotypes of the diploid oatA. strigosaoriginating from various geographical regions of the world. Six isoenzyme systems (AAT, ACP, EST, LAP, MDH, PX) were studied and 16 loci were identified. Only two loci (Est4andMdh2) were polymorphic. Ecotypes were characterized by the percentage of polymorphic loci (P=3.3%), the mean number of alleles per locus (A=1.04) and intrapopulation diversity (HS=0.013). Total genetic diversity (HT=0.07) and interpopulation diversity (DST=0.057) were examined as well. The value of the coefficient of gene differentiation (GST=0.821) indicated that diversity among populations was an important contributor to total variability. Genetic similarity betweenA. strigosapopulations was very high (IN=0.94). Cluster analysis did not demonstrate strongly differentiated groups among the ecotypes examined.


2016 ◽  
Vol 44 (2) ◽  
pp. 431-436 ◽  
Author(s):  
Masoumeh YOUSEFIAZARKHANIAN ◽  
Ali ASGHARI ◽  
Jafar AHMADI ◽  
Behvar ASGHARI ◽  
Ali Ashraf JAFARI

The genus Salvia includes an enormous assemblage of nearly 1,000 species dispersed around the world. Due to possible threats to this genus, there is an immediate requirement to evaluate the diversity of its wild populations. ISSR and RAPD molecular techniques were used to evaluate the genetic relationships among twenty-one ecotypes of eight Salvia species. Amplification of genomic DNA using 23 primers (15 RAPD and eight ISSR) produced 280 bands, of which 91% were polymorphic. The results of marker parameters showed no clear difference between two marker systems. It was generally observed that both ISSR and RAPD markers had similar efficiency in detecting genetic polymorphisms with remarkable ability to differentiate the closely related ecotypes of Salvia. Nei’s similarity coefficients for these techniques ranged from 0.48 to 0.98. Based on the results of clustering, PCoA and AMOVA, the genetic diversity between and within species was confirmed. So, conservation and domestication of the genus Salvia must be due to levels of genetic variations.


Antiquity ◽  
1994 ◽  
Vol 68 (260) ◽  
pp. 604-610 ◽  
Author(s):  
Christina Pavlides ◽  
Chris Gosden

The growing story of early settlement in the northwest Pacific islands is moving from coastal sites into the rainforest. Evidence of Pleistocene cultural layers have been discovered in open-site excavations at Yombon, an area containing shifting hamlets, in West New Britain's interior tropical rainforest. These sites, the oldest in New Britain, may presently stand as the oldest open sites discovered in rainforest anywhere in the world.


2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Christian Fatokun ◽  
Gezahegn Girma ◽  
Michael Abberton ◽  
Melaku Gedil ◽  
Nnanna Unachukwu ◽  
...  

Author(s):  
Alexandre A.F. Rivas ◽  
James R. Kahn

The world is experiencing a major dilemma between the need to reduce global warming and to promote economic development. Brazil has the largest tropical rainforest on the planet, which plays an important role in this scenario. In the heart of this forest there is a special economic zone (SEZ), the Manaus Free Trade Zone. Studies indicate that there is a positive relationship between this economic activity and the level of forest conservation in the state of Amazonas, where the Manaus Free Trade Zone is located. There is important literature on SEZs, examining their economic and environmental impact in general, and specifically examining the Manaus Free Trade Zone. There is also a proposal to turn this SEZ into a major Brazilian economic initiative to protect the Amazon rainforest.


2016 ◽  

Earth's human population currently exceeds 7 billion, and by the year 2050 our planet will have at least two billion more mouths to feed. When faced with providing food for so many people, the idea is often advanced that Australia will become the 'food bowl' of Asia. Australia currently grows enough food to feed about three times its population and agricultural exports are important to our economy; however, Australia's role in feeding the world needs careful consideration. This highly topical book draws together the latest intelligence on the sustainable production and distribution of food and other products from Australian farms. It examines questions that policy-makers, farmers, politicians, agricultural scientists and the general public are asking about the potential productivity of our arable land, the environmental and economic impacts of seeking to increase productivity, and the value of becoming cleaner and greener in our agricultural output. With chapters on the emergence of new markets, consumer trends in China, the biophysical constraints on agricultural expansion, and the various products of Australian agriculture and aquaculture, Australia's Role in Feeding the World provides valuable insight into the future of agriculture in this nation. The book is ideal reading for academics and students in agriculture, environmental sciences, economics, Australian studies, international development studies; agricultural practitioners; and the food production industry.


2008 ◽  
Vol 59 (8) ◽  
pp. 707 ◽  
Author(s):  
R. Lin ◽  
H. Yang ◽  
T. N. Khan ◽  
K. H. M. Siddique ◽  
G. Yan

Chickpea (Cicer arietinum L.) is one of the major grain legume crops in the world. In this study, the genetic diversity of 24 Australian chickpea cultivars released between 1987 and 2005 was investigated with microsatellite-anchored fragment length polymorphism (MFLP) DNA markers. Among the cultivars examined, 30 cultivar-specific markers were identified and all were unequivocally identified using the DNA fingerprints developed in this study. Most of the cultivars were grouped into two major clusters; cv. Flipper was separated from the rest based on total character differences of DNA polymorphism. The MFLP approach proved suitable in the analysis of genetic diversity among the chickpea cultivars studied and the genetic relationship identified will be useful for chickpea breeding programs in selecting parent materials.


1993 ◽  
Vol 118 (1) ◽  
pp. 119-129 ◽  
Author(s):  
Adam Dale ◽  
Patrick P. Moore ◽  
Ronald J. McNicol ◽  
Thomas M. Sjulin ◽  
Leonid A. Burmistrov

Pedigrees of 137 red raspberry (Rubus idaeus L.) varieties released throughout the world since 1960 were used to calculate: 1) the genetic contribution of founding clones to these varieties; 2) genetic relatedness among them; and 3) their inbreeding coefficients. Fifty founding clones contributed to the pedigrees of these varieties with a mean genetic contribution ranging from <0.1% to 21%. Varieties were clustered according to the genetic contribution into groups strongly related to geographical origin. Varieties developed in the former USSR and derived from `Novost Kuzmina' formed a distinct cluster. The remaining varieties were clustered in groups based mainly on whether they were of North American or European origin. Varieties were clustered also on the basis of Wright's coefficient of relationship-a measure of genetic relatedness. Cluster groups were related to their geographical origin and the varieties within the groups could be traced to similar intermediate parents. Inbreeding coefficients ranged from 0.0 to 0.625 and were related, in part, to the numbers of generations of controlled hybridization from common ancestors. The British group, with the largest number of generations of breeding, had a low mean inbreeding coefficient, indicating that inbreeding can be minimized with attention to the mating system. Strategies are suggested for maintaining and increasing the genetic diversity in the world's red raspberry breeding populations.


Sign in / Sign up

Export Citation Format

Share Document