Characterization of Streptomyces spp. from Rice Fields as a Potential Biocontrol Agent against Burkholderia glumae and Rice Plant Growth Promoter
, Erneeza Mohd Hata 2,*, Dzarifah Zulperi 3, Siti Izera Ismail 3, Mohd Razi Ismail 4,5, Nur Ain Izzati Mohd Zainudin 6, Noor Baity Saidi 7 and Mohd Termizi Yusof 1,*Round 1
Reviewer 1 Report
2. Material and Methods:
2.1. Sampling and isolaton
¿How many samples of soil, risosphere and endorphere of rice plants were obtained? from which the 50 isolates were obtained??
2.6.2. Effect of bacterial....
I think they were not exactly in vitro conditions and the reference 45 not mentioned in vitro conditions.
In this case it would be under laboratory and greenhouse conditions
Author Response
We have attached the edited manuscript as well as the response to the major and minor comments by the reviewer.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The manuscript describes isolation of streptomycete strains from rice field soil, rice rhizosphere and endosphere. The isolates were characterized by determination of inhibitory activity against Burkholderia glumae, enzymatic activities related to plant growth promotion, and impact of rice seed treatment on germination and growth of the seedlings. The topic is of general interest and some of the results may be promising, however, the manuscript suffers from serious flaws including description of experiments, data presentation and statistical analysis, that prevent its publication in the present form.
Major comments:
- The experiments testing the effect of seed treatment with bacterial isolates are described in a confusing way using inappropriate terms "in vitro" for seedlings grown under laboratory conditions and "in vivo" for those grown in a greenhouse. No further details are given for the latter, e.g. whether the seeds germinated in soil, sterilized soil, or some artificial substrate.
The results are presented as a heatmap (Fig. 5) and supplementary Table S2, both showing the parameters as percentage in comparison with the control. However, are they "percentage of Streptomyces-treated rice seedling’s relative to non-treated control seedlings" as stated in the both legends, or "Increase in germination, vigor and growth (%)" as written in the header of Table S2?
The measured values should be presented instead, accompanied by proper statistical analysis, i.e. showing whether the results of individual treatments significantly differed from the control.
- Both title and the introduction part suggest that antagonistic activity of the strains against Burkholderia glumae was the primary reason for their isolation. It is therefore rather surprising that this trait was tested on Petri dishes only. The title and text should be adapted accordingly.
Minor comments:
l. 82 - 92 The paragraph should be replaced with one or two sentences clearly stating what was done and why.
From l. 257, Fig. 2 - It is impossible to assign a species name to the isolate based on its 16S rRNA gene sequence. The bacterial species are not defined based this single property, therefore even if the sequence was identical to a validly described species, the isolate should be designated as Streptomyces sp.
Fig. 2a - Presenting a snapshot of an electrophoresis gel with PCR products of the same lengths is unnecessary.
Fig. 2c - A closer relative of the analyzed sequences should be used as an outgroup instead of B. subtilis.
The entire text needs to be revised to remove frequent grammatical and stylistic errors.
Author Response
Attached is the edited manuscript as well as the response to the major and minor comments by the reviewer.
Author Response File: Author Response.pdf
