Variation in seed and seedling traits of the different ethno-varieties of jackfruit, a potential fruit tree species for food security

A key component of the performance of plant seeds is the germination capability as well as seedling survival and vigor. Seed traits from five jackfruit ethno-varieties (infra-specific diversity as understood and managed by farmers) were assessed. A greenhouse experiment was conducted to determine the survival of seeds, emergence and germination rate. Seeds from different ethno-varieties differed in their length (F (4,145) = 6.31, p < 0.001). The difference was highest between seeds from white, orange or yellow ethno-varieties. The width also slightly differed among ethno-varieties (F (4,145) = 3.29, p < 0.05). The average fresh and dry weights tended to be higher in seeds from the soft ethno-variety than the rest of the ethno-varieties. Differences in the survival of seeds and germination rate were also exhibited among ethno-varieties, where the white ethno-variety showed the highest pre-emergence mortality but at the same time the least germination time. Over the six-week period of germination, the soft ethno-variety exhibited the highest root:shoot ratio but also grew faster than all other ethno-varieties. There is potential evidence of phylogenetic constraints on seed size, germination and seedling vigor. Optimum growth for most of the traits was achieved between 6 and 7 weeks after sowing, which can guide on the time seedlings should be left in the pots before being transferred to the field. Further progeny tests should be undertaken on these provenances in the field over a longer period so as to obtain better distinction of the growth traits among the ethno-varieties

Detection of Self Incompatibility Genotypes in Prunus africana: Characterization, Evolution and Spatial Analysis.

In flowering plants, self-incompatibility is an effective genetic mechanism that prevents self-fertilization. Most Prunus tree species exhibit a homomorphic gametophytic self-incompatibility (GSI) system, in which the pollen phenotype is encoded by its own haploid genome. To date, no identification of S-alleles had been done in Prunus africana, the only member of the genus in Africa. To identify S-RNase alleles and hence determine S-genotypes in African cherry (Prunus africana) from Mabira Forest Reserve, Uganda, primers flanking the first and second intron were designed and these amplified two bands in most individuals. PCR bands on agarose indicated 26 and 8 different S-alleles for second and first intron respectively. Partial or full sequences were obtained for all these fragments. Comparison with published S-RNase data indicated that the amplified products were S-RNase alleles with very high interspecies homology despite the high intraspecific variation. Against expectations for a locus under balancing selection, frequency and spatial distribution of the alleles in a study plot was not random. Implications of the results to breeding efforts in the species are discussed, and mating experiments are strongly suggested to finally prove the functionality of SI in P. africana

Structuring of genetic diversity in Albizia gummifera C.A.Sm. among some East African and Madagascan populations

No abstract for this articl

GPS coordinates of all the <i>Prunus africana</i> trees that were sampled for analysis of S-alleles.

<p>GPS coordinates of all the <i>Prunus africana</i> trees that were sampled for analysis of S-alleles.</p

Results of spatial genetic structure analysis in the second intron <i>S</i>-alleles of <i>P</i>. <i>africana</i>.

<p>Significant autocorrelation was detected in the first distance class (up to 100 m) between individuals. X-axis is spatial distance between individuals in metres, y-axis is Loiselle’s kinship coefficient for the second intron <i>S</i>-alleles</p

List of the 26 alleles detected in the second intron of the S-RNase of <i>P</i>. <i>africana</i>.

<p>List of the 26 alleles detected in the second intron of the S-RNase of <i>P</i>. <i>africana</i>.</p

Map showing the location of Mabira forest and the individual trees of <i>P</i>. <i>africana</i> sampled for S-allele analysis

<p>Map showing the location of Mabira forest and the individual trees of <i>P</i>. <i>africana</i> sampled for S-allele analysis</p

Aster fastigiatus Fisch.

原著和名: ヒメシヲン科名: キク科 = Compositae採集地: 千葉県 長柄郡 茂原町 (千葉県 茂原)採集日: 1950/9/23採集者: 萩庭丈壽整理番号: JH047356国立科学博物館整理番号: TNS-VS-99735

Phylogenetic tree (minimum evolution) of <i>P</i>. <i>africana</i> and other <i>Prunus</i> second intron <i>S</i>-RNase sequences depicting relationships with other congeneric species.

<p>Allele sequences are highly diverged and partially are similar to <i>S</i>-allele sequences obtained in other <i>Prunus</i> species, a pattern commonly observed as alleles are older than the species radiation.</p

Phylogenetic (minimum evolution) tree of <i>P</i>. <i>africana S</i>-RNase intron 2 sequences, showing the relationship among alleles.

<p>Phylogenetic (minimum evolution) tree of <i>P</i>. <i>africana S</i>-RNase intron 2 sequences, showing the relationship among alleles.</p