An EgHd3a-like and its alternatively spliced transcripts in the oil palm (Elaeis guineensis)

Heading date 3a (Hd3a) is an important flowering regulator of short-day plants, and plays a role in several developmental processes. The oil palm is commercially grown for the edible oil derived from its fruit. Flowering and fruit development are key factors for successful production, contributing to productivity of the oil palm fruit. Because little is known about the gene organization of Hd3a in the oil palm, the present study aimed at isolating the Hd3a and its regulatory region. Furthermore, alternatively spliced transcripts were cloned, and their expression in different tissues was also investigated. The structure of the oil palm Hd3a (EgHd3a-like) gene and its promoter were established based on the isolation of EgHd3a-like cDNA and genomic DNA. The promoter analysis revealed that it contains two key regulatory elements, CCAAT boxes and an ARR1 motif, which are the binding sites of Hd3a inducers. Other cis-elements corresponding to flowering and organ development were also represented. Expression of the transcript variants was investigated by RT-PCR in the anther, pistil, mesocarp and leaf. EgHd3a-like was expressed in all tissues tested, which supports its multifaceted roles in several developmental processes. The variants were found in all tested tissue types but at different levels, showing some level of tissuespecificity by variant. Taken together, these results indicate that EgHd3a-like is regulated under various conditions and that transcript variants might play an important role in gene function and regulation

Potential of Bacillus spp. isolated from food waste compost for controlling rice diseases

Bacterial leaf blight, bakanae and blast are severe, economically damaging rice diseases caused by Xanthomonas oryzae, Fusarium fujikuroi, and Magnaporthe oryzae, respectively. Bacillus spp. have been applied as bioactive, eco friendly agents to control these diseases. In this study, five antagonistic strains isolated from food waste compost, namely B. subtilis strain BS, B. amyloliquefacien strain C2-1, B. tequilensis strain 1-BA, B. licheniformis strain 2-BA, and Lysinibacillus. sp strain 3-BA were tested for their efficacy against rice diseases. The inhibition of X. oryzae was tested by paper disc diffusion, while the inhibitions of F. fujikuroi and M. oryzae were tested in dual cultures. It was found that B. amyloliquefacien strain C2-1 gave the widest clear zones. At 24 h, 48 h, 72 h and 7 days, the strain had produced zones of inhibition against X. oryzae of 7.41±0.65, 7.9±0.20, 8.8±0.65 and 8.90±0.12 mm, respectively. B. amyloliquefacien strain C2-1 also reduced the growth of the fungal rice pathogens F. fujikuroi and M. oryzae, achieving 98.79% and 97.74% inhibitions, respectively. B. amyloliquefaciens strain C2-1 was also effective against X. oryzae, F. fujikuroi, and M. oryzae in the greenhouse. Fourteen days after spraying rice plants with the B. amyloliquefacien strain C2-1, infections with X. oryzae, F. fujikuroi, and M. oryzae were inhibited by 60%, 37%, and 25%, respectively. The results suggested that B. amyloliquefacien strain C2-1 can be used as a biocontrol agent against bacterial leaf blight, bakanae, and rice blast diseases

A genome scan for quantitative trait loci affecting cyanogenic potential of cassava root in an outbred population

<p>Abstract</p> <p>Background</p> <p>Cassava (<it>Manihot esculenta </it>Crantz) can produce cyanide, a toxic compound, without self-injury. That ability was called the cyanogenic potential (CN). This project aimed to identify quantitative trait loci (QTL) associated with the CN in an outbred population derived from 'Hanatee' × 'Huay Bong 60', two contrasting cultivars. CN was evaluated in 2008 and in 2009 at Rayong province, and in 2009 at Lop Buri province, Thailand. CN was measured using a picrate paper kit. QTL analysis affecting CN was performed with 303 SSR markers.</p> <p>Results</p> <p>The phenotypic values showed continuous variation with transgressive segregation events with more (115 ppm) and less CN (15 ppm) than either parent ('Hanatee' had 33 ppm and 'Huay Bong 60' had 95 ppm). The linkage map consisted of 303 SSR markers, on 27 linkage groups with a map that encompassed 1,328 cM. The average marker interval was 5.8 cM. Five QTL underlying CN were detected. <it>CN08R1</it>from 2008 at Rayong, <it>CN09R1</it>and <it>CN09R2 </it>from 2009 at Rayong, and <it>CN09L1 </it>and <it>CN09L2 </it>from 2009 at Lop Buri were mapped on linkage group 2, 5, 10 and 11, respectively. Among all the identified QTL, <it>CN09R1 </it>was the most significantly associated with the CN trait with LOD score 5.75 and explained the greatest percentage of phenotypic variation (%Expl.) of 26%.</p> <p>Conclusions</p> <p>Five new QTL affecting CN were successfully identified from 4 linkage groups. Discovery of these QTL can provide useful markers to assist in cassava breeding and studying genes affecting the trait.</p