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Pereira, M. C. T.

Publications and source records attributed to Pereira, M. C. T..

2 recordsLinked to original sources

Consolidating the knowledge of the Caatinga's bryophytes: a comprehensive synthesis with new records

IntroductionThe Caatinga sensu lato (s.l.), a Seasonally Dry Tropical Forest, faces significant anthropogenic and climate change pressures. Bryophytes are crucial yet understudied components of this biome, with major knowledge gaps in their distribution, diversity, and conservation status. ObjectivesThis study aimed to consolidate and expand the knowledge of the Caatingas s.l. bryoflora by integrating data from field inventories, herbaria, and literature into a comprehensive occurrence database. MethodsFloristic surveys were conducted in five localities. A dataset was assembled from the three data sources. Multivariate Generalized Linear Models, UPGMA, and Indicator Value analyses compared bryophyte communities among vegetation types. Taxonomic beta diversity was calculated for the entire biome. Conservation analyses assessed species representativeness inside and outside Protected Areas. ResultsA total of 627 bryophyte taxa (608 species, 15 varieties, and 4 subspecies), including 54 endemics, was documented for the Caatinga s.l., with five new records added. Ecotone areas showed the highest richness (441 taxa). Bryophyte communities differed among vegetation types, with species turnover as the main driver of beta diversity (0.991). Although 76.4% of all taxa and 64.8% of endemic taxa have at least one record within a Protected Area. ConclusionsThe historical perception of low biodiversity in the Caatinga bryoflora is refuted, revealing high diversity across vegetation types. Data gaps in distribution and conservation status are addressed. Strong sampling bias towards Protected Areas likely overestimates in situ protection. Systematic sampling in under-collected regions and stronger conservation policies are urgently needed to safeguard this component of dry forest biodiversity

plant biology↗

Seedless fruit in Annona squamosa L. is monogenic and conferred by INO locus deletion in multiple accessions

Understanding the genetic basis and inheritance of a trait facilitates the planning of breeding and development programs of new cultivars. In the sugar apple tree (Annona squamosa L.), the mechanism of the desirable seedless trait in the Thai seedless (Ts) and Brazilian seedless (Bs) accessions was associated with a deletion of the INNER NO OUTER (INO) locus. Genetic analysis of F1, F2 and backcross descendants of crosses of Bs to fertile wild-type varieties showed that seedlessness was recessive and monogenic. Whole genome sequencing of a third accession, Hawaiian seedless (Hs), identified a 16 kilobase deletion including INO. The finding of an identical deletion in Ts and Bs indicated a common origin among genotypes, from a single deletion event. Analysis of microsatellite markers could not preclude the possibility that all three accessions are vegetatively propagated clones. The sequence of the deletion site enabled formulation of a codominant assay for the wild-type and mutant genes that validated the INO gene deletion as the cause of seedless trait, and can be used in the selection of new seedless varieties. The study findings and obtained progenies should be useful in breeding and introgression programs of the trait into elite sugar apple lines and into other Annonas by means of interspecific crossings.

genetics↗