scholarly journals A historical appraisal of the tropical forages collection conserved at CIAT

2020 ◽  
Vol 1 (2) ◽  
pp. 51-68
Author(s):  
Rainer Schultze-Kraft ◽  
Michael Peters ◽  
Peter Wenzl

A report on the tropical forage germplasm collection conserved in the CIAT genebank is presented. Emphasis is firstly on the assembling of the collection during 1972‒1993 through about 70 major and minor collecting missions in tropical America, Africa and Southeast Asia. Along with introductions from existing collections, currently some 1,600 accessions of 134 grass species and 21,000 accessions of 637 legume species are being maintained. Secondly, information on the utilization of the collection, with emphasis on cultivar development based on selection of accessions from the CIAT collection, is presented. Worldwide, a total of 44 grass and 34 legume cultivars derived from germplasm maintained at CIAT are reported. Information on germplasm distribution and knowledge sharing during the last four decades is also presented as well as a brief discussion on future needs.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Grimar Abdiel Perez ◽  
Pumipat Tongyoo ◽  
Julapark Chunwongse ◽  
Hans de Jong ◽  
Anucha Wongpraneekul ◽  
...  

AbstractThis study explored a germplasm collection consisting of 112 Luffa acutangula (ridge gourd) accessions, mainly from Thailand. A total of 2834 SNPs were used to establish population structure and underlying genetic diversity while exploring the fruit characteristics together with genetic information which would help in the selection of parental lines for a breeding program. The study found that the average polymorphism information content value of 0.288 which indicates a moderate genetic diversity for this L. acutangula germplasm. STRUCTURE analysis (ΔK at K = 6) allowed us to group the accessions into six subpopulations that corresponded well with the unrooted phylogenetic tree and principal coordinate analyses. When plotted, the STRUCTURE bars to the area of collection, we observed an admixed genotype from surrounding accessions and a geneflow confirmed by the value of FST = 0.137. AMOVA based on STRUCTURE clustering showed a low 12.83% variation between subpopulations that correspond well with the negative inbreeding coefficient value (FIS =  − 0.092) and low total fixation index (FIT = 0.057). There were distinguishing fruit shapes and length characteristics in specific accessions for each subpopulation. The genetic diversity and different fruit shapes in the L. acutangula germplasm could benefit the ridge gourd breeding programs to meet the demands and needs of consumers, farmers, and vegetable exporters such as increasing the yield of fruit by the fruit width but not by the fruit length to solve the problem of fruit breakage during exportation.


Genes ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 957
Author(s):  
Paulina Tomaszewska ◽  
Till K. Pellny ◽  
Luis M. Hernández ◽  
Rowan A. C. Mitchell ◽  
Valheria Castiblanco ◽  
...  

Urochloa (including Brachiaria, Megathyrus and some Panicum) tropical grasses are native to Africa and are now, after selection and breeding, planted worldwide, particularly in South America, as important forages with huge potential for further sustainable improvement and conservation of grasslands. We aimed to develop an optimized approach to determine ploidy of germplasm collection of this tropical forage grass group using dried leaf material, including approaches to collect, dry and preserve plant samples for flow cytometry analysis. Our methods enable robust identification of ploidy levels (coefficient of variation of G0/G1 peaks, CV, typically <5%). Ploidy of some 348 forage grass accessions (ploidy range from 2x to 9x), from international genetic resource collections, showing variation in basic chromosome numbers and reproduction modes (apomixis and sexual), were determined using our defined standard protocol. Two major Urochloa agamic complexes are used in the current breeding programs at CIAT and EMBRAPA: the ’brizantha’ and ’humidicola’ agamic complexes are variable, with multiple ploidy levels. Some U. brizantha accessions have odd level of ploidy (5x), and the relative differences in fluorescence values of the peak positions between adjacent cytotypes is reduced, thus more precise examination of this species is required. Ploidy measurement of U. humidicola revealed aneuploidy.


Vaccine ◽  
2017 ◽  
Vol 35 (51) ◽  
pp. 7147-7153 ◽  
Author(s):  
Mana Mahapatra ◽  
Sasmita Upadhyaya ◽  
Sharie Aviso ◽  
Aravindh Babu ◽  
Geoff Hutchings ◽  
...  

2008 ◽  
Vol 10 (1) ◽  
Author(s):  
U. R. Averweg

The intranet is a common feature in many organizations. With the increasing use of a technology infrastructure in organizations, there is a continued challenge for employees in an organization to contribute their knowledge willingly and to make use of knowledge sharing with other employees. Intranets are well-suited for use as a strategic tool in knowledge sharing due to their ability to support the distribution, connectivity and publishing of data and information. Intranets should be seen as integral to an organization’s knowledge management strategy and should be tailored to suit and enhance an organization’s knowledge-sharing activities. The question arises: To what extent does an organization’s existing intranet facilitate knowledge sharing? From a practitioner-based inquiry perspective, this question was explored by the selection of a large organization – eThekwini Municipality, Durban, South Africa – as the field of application. Derived from a mixed methodology approach, the results of a survey are presented. It is suggested that encouragement be given for more practitioner-based inquiry research.


1997 ◽  
Vol 45 (5) ◽  
pp. 919 ◽  
Author(s):  
R. W. Rogers ◽  
C. Stride

The distribution of grass species and a selection of attributes of those species were related to distance from water in an otherwise natural, sheep-grazed, semi-arid, subtropical grassland at Glencoban Station near Cunnamulla in south-western Queensland, Australia. Twenty common species could be classified as decreaser, increaser or neutral with respect to stocking pressure based on distribution patterns with respect to distance from water. No species known to be introduced to Australia were present. The occurrence of a diversity of vegetative and diaspore attributes and carbon assimilation pathways were also shown to be related to stocking pressure. The attributes studied showed autocorrelation in two groups, which related to the higher level taxonomy of the grasses and to response to stocking. Chloridoid grasses increase and andropogonoid grasses decrease under high stocking pressure. In this grassland, which has no introduced species, a syndrome of stocking-related attributes can be discerned.


1972 ◽  
Vol 12 (56) ◽  
pp. 240 ◽  
Author(s):  
KFM Reed ◽  
RW Snaydon ◽  
A Axelsen

Young sheep were rotationally grazed, at two stocking rates, on pasture sown to combinations of two legume species (lucerne or subterranean clover) and two grass species (a mixture of annual and biennial ryegrass or phalaris) at Canberra. Liveweight gains were 45 per cent greater, and wool production was 10 per cent greater, on the lucerne dominant pasture (87 per cent lucerne) than on the grass dominant subterranean clover pasture (8 per cent subterranean clover). The differences were maximum during summer, but also occurred during spring. Mortality and supplementary feed requirement on grass dominant pasture was double that on lucerne pasture. Liveweight gains were 13 per cent greater on pasture sown to ryegrass than on pasture sown to phalaris. Sheep mortality was eight times greater on the phalaris than on the ryegrass pasture, and survival feed requirements at least double. The superior animal production from lucerne pasture was due mainly to the ability of lucerne to grow during periods of low rainfall and to maintain a high production of legume in the pasture.


2001 ◽  
Vol 79 (10) ◽  
pp. 1241-1247 ◽  
Author(s):  
Ji-Chuan Kang ◽  
Pedro W Crous ◽  
Kenneth M Old ◽  
Mark J Dudzinski

Cylindrocladium quinqueseptatum Boedijn & Reitsma was originally described from leaf spots of Hibiscus sabdariffa L. from Indonesia. This fungus infects many host plants in Southeast Asia and causes severe leaf blight disease of eucalypts. Calonectria quinqueseptata Figueiredo & Namek., which was described from leaf spots on Annona squamosa L. from Brazil, has been regarded as the teleomorph of Cy. quinqueseptatum. Based on morphology and on the phylogeny derived from the DNA sequence of a β-tubulin gene portion spanning several phylogenetically informative introns, the two respective ex-type cultures are shown to be distinct species. Furthermore, Calonectria reteaudii (Bugn.) C. Booth (anamorph Cy. reteaudii (Bugn.) Boesew.), which was described on Smithia bequaertii De Wild. from Vietnam, is shown to be morphologically identical to a comprehensive selection of isolates of Cy. quinqueseptatum from Southeast Asia, Australia, and Madagascar. As Cy. reteaudii represents an older name for Cy. quinqueseptatum, we suggest that the fungus causing widespread damage on eucalypts and other hosts in the above regions be referred to as Cy. reteaudii. Calonectria quinqueseptata should be retained for the fungus that thus far has been found only in Brazil.Key words: Cylindrocladium reteaudii, Eucalyptus, Hypocreales, phylogeny, systematics.


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