La naranja agria (Citrus aurantium L.) presenta un alto valor nutricional y gastronómico en el distrito de Huacho, Lima, Perú, pero en la actualidad se considera una especie en peligro de desaparecer del distrito y alrededores por problemas fitosanitarios. Para la recuperación y repoblación de esta especie se planteó emplear técnicas biotecnológicas para la obtención de plantas libres de patógenos. Por lo tanto, el objetivo de la presente investigación fue micropropagar in vitro naranja agria a partir de segmentos nodales. Los segmentos nodales de naranja agria fueron desinfectados en diferentes concentraciones de NaClO, luego se introdijeron en medio de cultivo MS (Murashige y Skoog) adicionado con BAP, KIN y AG3 para la fase de multiplicación, posteriormente se transfirieron a medios MS adicionado con IBA y ANA para la fase de enraizamiento. La evaluación del porcentaje de contaminación se realizó a los diez días, la evaluación de formación de brotes en fase de multiplicación se realizó a los 30 días y la evaluación de enraizamiento a los 30 días. En la fase de desinfección y establecimiento in vitro se logró obtener 0% de contaminación y 0% de oxidación de los explantes. En la fase de multiplicación in vitro los mejores resultados se obtuvieron en el medio de cultivo M8 generando 4,7 brotes por explante. Y finalmente en la fase de enraizamiento el medio E4 permitió obtener 94,7% de explantes enraizados, 23,4 mm de longitud de raíz y 2,2 raíces por explante.

Cocoa (Theobroma cacao L.) is one of the most important economic crops worldwide. The propagation of elite varieties of cocoa has been achieved through somatic embryogenesis, but still one of the main limitations is the low rates of embryo formation, which is a genotype-dependent trait. Manipulation of transcription factors (TFs) such as BABY BOOM (BBM) promotes the transition of cocoa somatic cells from the vegetative to the embryonic state. This work validated the use of clonal cocoa leaves cv. IMC-67 to induce somatic embryogenesis, overcoming their recalcitrant limitation with the help of the introduction of TF-BBM from Arabidopsis thaliana (AtBBM). The vectors were constructed by the Gateway system using the donor vector pENTR/D-TOPO and the expression vector pk7WG2. The overexpression vector pk7WG2:AtBBM was obtained, allowing successful transformation into Agrobacterium tumefaciens GV3101. The AtBBM gene was characterized (1755 base pairs), and its expression was observed in the formation of embryogenic calluses in cocoa leaves. Overexpression of AtBBM allowed the obtainment of a 92% response in the formation of embryogenic callus in cocoa leaves with Agrobacterium-mediated vacuum infiltration and overexpression of the pk7WG2:AtBBM vector. This high transformation efficiency reached with the insertion of the overexpression vector provides validation of transient response of the TF AtBBM in the formation of embryogenic calluses in cocoa leaves of the IMC-67 clone. Through this methodology, it is possible to continue with studies of gene overexpression, insertion, silencing, and gene editing in Peruvian cocoa.

The rocoto (Capsicum pubescens Ruiz & Pav.) (Solanaceae) is an endemic herbaceous chili pepper from Peru. Low yields of rocoto production are due to the low availability of certified seeds or the production of superior plant seedlings. Therefore, the present study aimed to establish an in vitro protocol for the regeneration and multiplication of rocoto shoots. The multiplication was carried out on shoot tips excised from rocoto seedlings germinated under in vitro conditions, and then the explants were placed on Murashigue and Skoog (MS) medium supplemented with different concentrations of 6-benzylaminopurine (BAP) and Kinetin: 0.5, 1.0, 1.5 and 2.0 mg/L. For rooting, shoots were obtained from the multiplication phase and placed under different treatments made up of MS medium supplemented with different concentrations of indole butyric acid (IBA) and naphthalene acetic acid (NAA): 0.5, 1.0, 1.5 and 2.0 mg/L. In the multiplication phase, the best results were observed with MS medium supplemented with 1.0 mg/L BAP, with 82.22% shoot development, 2.93 shoots per explant and 2.75 cm shoot length. In the rooting phase, the best results were observed with MS medium supplemented with 1.5 mg/L IBA, with 91.11% root development, 9.73 roots per explant and 6.79 cm root length. Here, we show the first evidence and tool for the in vitro regeneration and multiplication of rocoto chili pepper, which could be used for the multiplication of superior genotypes, germplasm in vitro conservation and its use in plant breeding programs.

This study focused on the in vitro propagation and DNA barcoding of the endangered herb Solanum corymbosum from the La Joya Desert, Peru. The primary objective of this study was to establish a protocol for the in vitro conservation and molecular identification of these species. This study used cytokinins, specifically BAP and TDZ, for shoot regeneration from leaf explants, achieving high rates of shoot regeneration and proliferation. The optimal concentration of TDZ (1 mg/L) resulted in 88.7% regeneration. In the rooting phase, auxins, specifically, IBA and NAA, were used, achieving high rooting rates and root numbers. The optimal concentration of IBA (2 mg/L) resulted in 100% rooting and 9.8 roots per shoot. DNA barcoding with four cpDNA markers (matK, rbcL, trnL-trnF, and psbA-trnH) allowed accurate molecular identification, confirming species identity within the genus Solanum. Key results included successful in vitro propagation with high rates of shoot formation and rooting and 100% survival during acclimatization. Molecular analysis confirmed the taxonomic identification of S. corymbosum, with high percentages of similarity (97% to 100%) with other Solanum species. Phylogenetic analysis confirmed its classification within the Radicans clade, sharing its characteristics with other Andean species of the genus Solanum. This study revealed that the propagation in vitro protocol and DNA barcoding are effective tools for the conservation of S. corymbosum, offering valuable methods for the conservation and genetic study of this and other threatened plant species.

El rocoto (Capsicum pubescens Ruiz & Pav.) es una solanácea con centro de origen en Perú, con gran valor gastronómico. Es afectado por enfermedades que limitan su desarrollo, diseminadas por semillas infectadas. El cultivo in vitro de tejidos vegetales permite propagar genotipos elites disponiendo de material vegetal libre de patógenos. El objetivo fue determinar la respuesta in vitro de rocoto en el establecimiento de semillas y regeneración a partir de yemas terminales. Se emplearon semillas de rocoto en diferentes tratamientos con hipoclorito de sodio. Se eliminaron hojas y raíces de rocotos germinados in vitro, quedando epicótilos con yemas terminales y se transfirieron a medios de cultivo con diferentes concentraciones de sales y vitaminas MS para la fase de regeneración in vitro, se evaluó la respuesta organogénica y oxidación. En el establecimiento de semillas de rocoto se obtuvo 100% de desinfección empleando etanol (70%) e hipoclorito de sodio (2%) durante 15 minutos, en la fase de regeneración el medio de cultivo con sales y vitaminas MS al 100% de concentración permitió obtener 19,8% de respuesta organogénica. Se estableció el protocolo del establecimiento in vitro de semillas de rocoto y se determinó baja respuesta organogénica a partir de yemas terminales en condiciones in vitro.

Myrciaria dubia (Kunth) McVaugh (camu‐camu) is a shrub native to the Amazon region that produces fruits with a high content of vitamin C and various bioactive compounds, making it a functional food with antioxidant, anti‐inflammatory, and antimicrobial properties. However, it is unknown which microorganisms are associated with its root system and can influence its growth and productivity. Arbuscular mycorrhizal fungi (AMF) are associated with most plants and are essential for their establishment, survival, and productivity since they facilitate their nutrition, increase water absorption, and improve soil structure. Although the AMF association is already known in some species of Myrciaria, no report is available on its association in M. dubia. This study presents, for the first time, the symbiotic association between AMF and M. dubia from the INIA San Roque experimental station located in the Amazon region, Peru. For the morphological and molecular analyses of the AMF, samples of rhizospheric soil and roots from two native accessions of the National Germplasm Bank of M. dubia were collected. Eighteen AMF morphospecies were identified in rhizospheric soil, belonging to nine genera Acaulospora, Ambispora, Entrophospora, Diversispora, Gigaspora, Glomus, Paraglomus, Funneliformis, and Sclerocystis, being the first one the most frequent. The roots of M. dubia showed high colonization by AMF (mean = 91%), and characteristic structures of arbuscular mycorrhizae, such as vesicles, hyphae, and arbuscules, could be observed. Likewise, the molecular analysis detected the presence of genetic material (rDNA) corresponding to AMF in the roots of both accessions. Our results evidenced the symbiotic association between AMF and M. dubia, which encourages further investigation of the functional potential of these microorganisms in this economically crucial agricultural plant in Peru.