METHODS AND RESULTS: This study aimed to isolate and characterize the full-length cDNA encoding ERG11 from G. boninense. The G. boninense ERG11 gene expression during interaction with oil palm was also studied. A full-length 1860 bp cDNA encoding ERG11 was successfully isolated from G. boninense. The G. boninense ERG11 shared 91% similarity to ERG11 from other basidiomycete fungi. The protein structure homology modeling of GbERG11 was analyzed using the SWISS-MODEL workspace. Southern blot and genome data analyses showed that there is only a single copy of ERG11 gene in the G. boninense genome. Based on the in-vitro inoculation study, the ERG11 gene expression in G. boninense has shown almost 2-fold upregulation with the presence of oil palm.
CONCLUSION: This study provided molecular information and characterization study on the G. boninense ERG11 and this knowledge could be used to design effective control measures to tackle the BSR disease of oil palm.
RESULTS: The sizes of the 27 ACP mitogenome sequences ranged from 14 986 to 15 030 bp. Along with three previously published mitogenome sequences, the 30 sequences formed three major mitochondrial groups (MGs): MG1, present in southwestern China and occurring at elevations above 1000 m; MG2, present in southeastern China and Southeast Asia (Cambodia, Indonesia, Malaysia, and Vietnam) and occurring at elevations below 180 m; and MG3, present in the USA and Pakistan. Single nucleotide polymorphisms in five genes (cox2, atp8, nad3, nad1 and rrnL) contributed mostly in the ACP diversity. Among these genes, rrnL had the most variation.
CONCLUSION: Mitogenome sequences analyses revealed two major phylogenetic groups of ACP present in China as well as a possible unique group present currently in Pakistan and the USA. The information could have significant implications for current ACP control and HLB management. © 2018 Society of Chemical Industry.
MATERIALS AND RESULTS: Four bioformulations consisting of dry (pesta granules, talc powder and alginate beads) and liquid formulations were evaluated for their ability to control Foc-TR4, sustain microbial populations after application and maintain microbial stability during storage. All tested bioformulations reduced disease severity (DS) by more than 43·00% with pesta granules producing the highest reduction in DS by 66·67% and the lowest area under the disease progress curve value (468·75) in a glasshouse trial. Microbial populations of DRB1 and CBF2 were abundant in the rhizosphere, rhizoplane and within the roots of bananas after pesta granules application as compared to talc powder, alginate beads and liquid formulations 84 days after inoculation (DAI). The stability of both microbial populations after 180 days of storage at 4°C was the greatest in the pesta granule formulation.
CONCLUSION: The pesta granule formulation was a suitable carrier of biological control agents (BCA) without compromising biocontrol efficacy, microbial population and storage stability as compared to other bioformulations used in this study.
SIGNIFICANCE AND IMPACT OF THE STUDY: Pesta granules could be utilized to formulate BCA consortia into biofertilizers. This formulation could be further investigated for possible applications under agricultural field settings.
METHODS AND RESULTS: Based on the sequences of internal transcribed spacer (ITS), TEF1-α and β-tubulin, as well as on the phylogenetic analysis of combined sequences, four species of Lasiodiplodia (L. theobromae,L. pseudotheobromae, L. iranensis, L. mahajangana) and two species of Neofusicoccum (N. ribis, N. parvum) were identified. Pseudofusicoccum violaceum, Neoscytalidium dimidiatum and three species of Botryosphaeria (B. scharifii, B. dothidea, B. ramosa) were identified based on sequences of ITS and TEF1-α. Pathogenicity test of selected isolates were tested on Chok Anan, Waterlily and Falan mango cultivars. Generally, all species were observed to be pathogenic on the three tested mango cultivars on wounded fruits, except for N. ribis and N. parvum, which were pathogenic on both wounded and unwounded fruits. However, N. ribis was only pathogenic on cultivar Falan, whereas B. ramosa were pathogenic on cultivars Waterlily and Falan.
CONCLUSIONS: Eleven species of Botryosphaeriaceae were associated with mango stem-end rot in Malaysia. To the best of our knowledge, four species, namely L. mahajangana, B. ramosa, N. ribis and P. violaceum are the first recorded Botryosphaeriaceae fungi associated with stem end rot of mango.
SIGNIFICANCE AND IMPACT OF THE STUDY: The identification of Botryosphaeriaceae fungi is important to establish suitable control measures and quarantine requirements. Many species have a wide host range, which means that there is a possibility of cross infection from other infected plants.