A method for generating virus-free cassava plants to combat viral disease epidemics in Africa.

Here, we report a method to clean cassava plants from viral infections that cause cassava mosaic and brown streak diseases in Africa. Infected plants of resistant or tolerant varieties from Malawi, Mozambique, Kenya, Tanzania and Uganda were cleaned in the UK using a combination of tissue culture, chemotherapy and thermotherapy. In the first cycle of our virus-indexing procedure, we successfully cleaned 27 of the 31 varieties (87%), and after an additional three cleaning cycles, all plants were virus-free. Virus-free tissue-cultured plants were shipped back to Africa for distribution to farmers. This first cross-boundary effort provides important lessons for mitigating the two-major cassava viral diseases.

The effects of the phytochemistry of cocoa on the food chemistry of chocolate(s) and how disease resistance in cocoa can be improved using CRISPR/Cas9 technology.

Consumers' rating of "chocolate brands" are majorly based on texture and taste rather than packaging. The texture/taste of a chocolate bar is largely influenced by the cocoa variety used for its production, whereas, its bioactive constituent is directly affected by the seed processing/chocolate manufacturing technique(s) adopted, and the additives used. Cacao is the key ingredient for chocolate production; therefore, the choicest varieties must be used to protect consumers' interest. Currently, the availability of the African variety is the only reason why it is globally sought-after for chocolate production rather than its taste. Therefore, a transfer of genetic materials from quality cocoa breeds into the high-yielding and resilient African variety or vice versa, would inferably increase the availability of quality cocoa beans all-year-round, and also increase the chances of obtaining sumptuous and palatable chocolates anywhere in the world.

Genetic diversity and population structure of Camellia huana (Theaceae), a limestone species with narrow geographic range, based on chloroplast DNA sequence and microsatellite markers.

Camellia huana is an endangered species with a narrow distribution in limestone hills of northern Guangxi and southern Guizhou provinces, China. We used one chloroplast DNA (cpDNA) fragment and 12 pairs of microsatellite (simple sequence repeat; SSR) markers to assess the genetic diversity and structure of 12 C. huana populations. A total of 99 alleles were detected for 12 polymorphic loci, and eight haplotypes and nine polymorphic sites were detected within 5200 bp of cpDNA. C. huana populations showed a low level of genetic diversity (n = 8, Hd = 0.759, Pi = 0.00042 for cpDNA, N A  = 3.931, H E  = 0.466 for SSRs), but high genetic differentiation between populations (F ST  = 0.2159 for SSRs, F ST  = 0.9318 for cpDNA). This can be attributed to the narrow distribution and limestone habitat of C. huana. STRUCTURE analysis divided natural C. huana populations into two groups, consistent with their geographical distribution. Thus, we suggest that five natural C. huana populations should be split into two units to be managed effectively.

Functional redundancy in Echinocandin B in-cluster transcription factor ecdB of Emericella rugulosa NRRL 11440.

Echinocandin B is a potent antifungal against the majority of fungal pathogens and its biosynthesis occurred by ecd and hty gene clusters in Emericella rugulosa NRRL 11440. We elucidated the functional necessity of in-clustered transcription factor; ecdB in the production of echinocandin B. We deleted the ecdB gene and found that ΔecdB mutant has no significant effect on echinocandin B production. The expression level of most of the ecd and hty cluster genes was not significantly altered except few of them up-regulated in knockout strain. The complete abrogation in ecdB gene expression was observed in ΔecdB strain. However, the interactions of purified EcdB protein with DNA sequence of ecdA, ecdH, ecdK and ecdI promoter was confirmed in-vitro. Our results conclude that EcdB protein in-vitro binds to the ecdA, ecdH, ecdK and ecdI promoter but in-vivo, it could not significantly affect the gene expression and echinocandin B production in Emericella rugulosa.