Rapid plant DNA and RNA extraction protocol using a bench drill

Plant DNA and RNA extraction methods are well established, with a wide range of protocols, depending on the purposes of each laboratory/research. Nowadays, quick, inexpensive and easy plant DNA and RNA extraction methods are highly sought after. We developed an optimized protocol for plant DNA and RNA extraction that uses an inexpensive bench drill and plastic bags and does not require liquid nitrogen. DNA from leaves and RNA from leaves and roots of banana, pineapple, citrus, papaya, passion fruit and cassava, were extracted using a basic cetyltrimethylammonium bromide method. Both nucleic acids were quantified and evaluated for quality based on agarose gel electrophoresis. The DNA and RNA extractions were successful for all species, and RNA quality in pellets was maintained after storage at room temperature for three weeks. This protocol can reduce costs considerably in laboratories with ongoing routine activities of DNA and RNA extraction for genetic diversity and gene expression analyses, where other conventional methods have not been successful due to explant, condition of samples and quantity and quality of nucleic acids. This is especially relevant for many laboratories in developing countries where the cost and availability of liquid nitrogen may be a constraint

Characterization And Selection Of Passion Fruit (yellow And Purple) Accessions Based On Molecular Markers And Disease Reactions For Use In Breeding Programs

Passiflora edulis Sims, which is native to South America, stands out as a passion fruit species with major potential for fruit production and marketing. This species is popularly known as yellow or purple passion fruit, depending on the color of the fruits produced. Brazil is the major worldwide producer of passion fruit; however, the average productivity of the country is low compared with its potential for culture. Fungal, bacterial and viral pathogens are among the factors limiting the productivity of passion fruit. Furthermore, no existing cultivars exhibit both productivity and resistance to disease. To select genetic material that will be useful for core collections and for increasing the genetic resistance of passion fruit cultivars to pathogens, we characterized 36 accessions based on 23 microsatellite loci and six variables related to the reactions to three diseases (woodiness virus, scab and anthracnose). We identified 127 alleles (an average of 5.52 alleles per locus), 30 % of which were private for yellow or purple passion fruit accessions. Analysis of variance and mean comparison tests indicated differences in five of the six variables (p < 0.05, Scott-Knott test). Differences between the average reactions of the yellow and purple passion fruit accessions were also observed for the symptoms of woodiness virus and anthracnose (p < 0.05, Mann-Whitney test).Together with these results, molecular and phenotypic estimates allowed the identification of groups of preferential accessions for use in breeding programs, for example, accessions BGP029, 071, 168, 205 and 277. © 2014 The Author(s)

Sesbania virgata stimulates the occurrence of its microsymbiont in soils but does not inhibit microsymbionts of other species Sesbania virgata estimula a ocorrência de seu microssimbionte nos solos, mas não inibe os microssimbiontes de outras espécies

The legume species Sesbania virgata establishes a specific and efficient symbiosis with Azorhizobium doebereinerae. Previous studies have shown that A. doebereinerae occurrence correlates to the presence of S. virgata. This work aimed to evaluate the occurrence of A. doebereinerae and of other nitrogen-fixing Leguminosae-nodulating bacteria (NFLNB) in soil samples collected adjacent to and 10 m away from the stems of five S. virgata plants in pasture areas. Symbiotic characteristics of isolates from these NFLNB populations were also studied. S. virgata and the four promiscuous legume species Leucaena leucocephala, Macroptilium atropurpureum, Phaseolus vulgaris and Vigna unguiculata were inoculated with soil samples to trap A. doebereinerae and other NFLNB. NFLNB capable of inducing nodulation in at least one of these legumes were found in all samples. M. atropurpureum was the most promiscuous species, as it trapped the highest number of NFLNB cultural types from soil suspensions. The other species were less promiscuous in the following order: V. unguiculata, P. vulgaris, and L. leucocephala. Isolates of the promiscuous legumes were classified into seven cultural groups. One of these groups, isolated from all promiscuous species, showed fast-growth alkali-reaction in culture medium (like Azorhizobium); it was identified as Cupriavidus. This is the first report of symbiosis of Cupriavidus with Papilionoideae species. The symbiotic efficiency of promiscuous hosts with NFLNB varied, but it was always less than that of controls with mineral nitrogen or an inoculant strain. S. virgata was efficiently nodulated only by A. doebereinerae, which occurred mainly in samples collected close to the plant stem, corroborating a high stimulus by its host species. A high diversity of NFLNB occurs as saprophytes close to the S. virgata root system.<br>A espécie de leguminosa Sesbania virgata estabelece uma simbiose especifica e eficiente com Azorhizobium doebereinerae. Estudos prévios indicam que a ocorrência de A. doebereinerae esta relacionada à presença de S. virgata. Avaliou-se a ocorrência de A. doebereinerae e de outras Bactérias Fixadoras de Nitrogênio Nodulíferas em Leguminosas (BFNNL) em amostras de solos coletadas próximo e a 10 metros do caule de cinco plantas de S. virgata em áreas de pastagem. As características simbióticas de isolados das populações dessas BFNNL foram também estudadas. Para captura de A. doebereinerae e de outras BFNNL, essas amostras de solos foram inoculadas em S. virgata e nas leguminosas promíscuas Leucaena leucocephala, Macroptilium atropurpureum, Phaseolus vulgaris e Vigna unguiculata. Todas as amostras de solos apresentaram BFNNL capazes de nodular, pelo menos, uma espécie. M. atropurpureum foi a espécie mais promíscua capturando um grande número de tipos culturais de BFNNL das suspensões de solo. As outras espécies foram menos promíscuas na seguinte ordem: V. unguiculata, P. vulgaris, e L. leucocephala. Os isolados das espécies hospedeiras consideradas promíscuas foram agrupados em sete tipos culturais. Um desses grupos, isolado de todas as espécies promiscuas, apresentou crescimento rápido e reação alcalina em meio de cultura (como Azorhizobium) e foi identificado como Cupriavidus. Este é o primeiro relato da simbiose de Cupriavidus com espécies de Papilionoideae. A simbiose de BFNNL com as demais espécies teve eficiência variável, mas foi sempre menor que a da adubação nitrogenada e da estirpe recomendada como inoculante. S. virgata formou simbiose somente com A. doebereinerae, a qual foi mais freqüente nas amostras de solos coletadas próximo ao caule da planta, corroborando alto estímulo deste microsimbionte por sua espécie hospedeira. Uma alta diversidade de BFNNL ocorre saprofiticamente próximo ao sistema radicular de S. virgata