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Recibido 05 septiembre 2011; aceptado 08 noviembre 2011 Resumen El objetivo del presente trabajo fue caracterizar y evaluar morfológicamente la colección nacional de germoplasma de camu camu del INIA compuesta por 43 accesiones, colectadas en la región Loreto, con fines de conservación y uso. Los resultados muestran que el germoplasma de camu camu presenta alta variabilidad y tres tipos de arquitectura de planta (columnar, intermedia o acaule y cónica o ramificada). Las flores son hermafroditas o andróginas y presentan hercogamia que faculta la alogamia o polinización cruzada. El color del fruto depende del estado de maduración del mismo, varía desde verde hasta rojo violáceo; el número de semillas por fruto varía desde 1 hasta 4; el número de frutos por kilogramo es de 90 a 148. Se encontraron 21 accesiones con rendimientos mayores de 15 kg por planta y 16 accesiones que superan los 2000 mg de ácido ascórbico/100 g de pulpa. Además, se identificaron 10 accesiones promisorias por rendimiento de frutos y por contenidos de ácido ascórbico. A través de Análisis de Componentes Principales se determinó que las variables más vinculadas en forma positiva son el rendimiento de fruto, altura de planta y el diámetro de tallo. El dendrograma derivado del análisis de conglomerados, permitió la identificación de tres grupos basados en el rendimiento de fruto; el primer grupo está formado por 22 accesiones cuyos rendimientos de fruto están entre 2.29 y 11.97 kg/planta, el segundo grupo por 16 accesiones que tienen rendimientos de 16.97 hasta 30.35 kg/planta, y el tercer grupo formado por 5 accesiones con rendimientos desde 36.52 hasta 39.24 kg/planta.

Camu camu is a typical Amazon native fruit shrub that possesses a diploid genome, moderate genetic diversity, and population structure. The fruits accumulate several essential nutrients and synthesize L-ascorbic acid (vitamin C) in great quantities and an array of diverse secondary metabolites with corroborated in vitro and in vivo health-promoting activities. These beneficial effects include antioxidative and antiinflammatory activities, antiobesity, hypolipidemic, antihypertensive and antidiabetic effects, DNA damage and cancer protection effects, and other bioactivities. Many health-promoting phytochemicals are biosynthesized in several metabolic pathways of camu camu. Their reconstruction from the fruit transcriptome database was accomplished by our research group. These include basic metabolic pathways such as glycolysis and pentose phosphate pathway, vitamin C biosynthesis pathways, and pathways involved in secondary metabolites production. Due to their agronomic potential and fruits growing demand, recently, based on an ideotype, programs were initiated for their domestication and genetic improvement, but so far with very negligible achievements. Consequently, we propose new strategies to accelerate the processes of domestication and genetic improvement based on state of the art technologies for multiomic data analysis and innovative molecular tools.

Myrciaria dubia is a main source of vitamin C for people in the Amazon region. Molecular studies of M. dubia require high-quality total RNA from different tissues. So far, no protocols have been reported for total RNA isolation from leaves of this species. The objective of this research was to develop protocols for extracting high-quality total RNA from leaves of M. dubia. Total RNA was purified following two modified protocols developed for leaves of other species (by Zeng and Yang, and by Reid et al.) and one modified protocol developed for fruits of the studied species (by Silva). Quantity and quality of purified total RNA were assessed by spectrophotometric and electrophoretic analysis. Additionally, quality of total RNA was evaluated with reverse-transcription polymerase chain reaction (RT-PCR). With these three modified protocols we were able to isolate high-quality RNA (A260nm/A280nm >1.9 and A260nm/A230nm >2.0). Highest yield was produced with the Zeng and Yang modified protocol (384±46µg ARN/g fresh weight). Furthermore, electrophoretic analysis showed the integrity of isolated RNA and the absence of DNA. Another proof of the high quality of our purified RNA was the successful cDNA synthesis and amplification of a segment of the M. dubia actin 1 gene. We report three modified protocols for isolation total RNA from leaves of M. dubia. The modified protocols are easy, rapid, low in cost, and effective for high-quality and quantity total RNA isolation suitable for cDNA synthesis and polymerase chain reaction.