Effect of salinity tolerant PDH45 transgenic rice on physicochemical properties, enzymatic activities and microbial communities of rhizosphere soils

Figures & data

Figure 1. (A) Schematic structure of the pCAMBIA1301-PDH45 construct used for rice plant transformation. (B) PDH45 overexpressing T1 transgenics and WT rice plants under salt stressed (200 mM NaCl) and non-stressed conditions after 3 mo. Treatments: WT+salt, WT-salt, T1-PDH45+salt, T1-PDH45-salt.

Table 1. Physico-chemical properties of soil

Properties	Values (New Delhi, India)				Values (Odisha, India)
	WT control	WT salt	PDH45 control	PDH45 salt	WT control	WT salt	PDH45 control	PDH45 salt
Sand (%)	62	62	62	62	71	71	71	71
Slit (%)	21	21	21	21	18	18	18	18
Clay (%)	17	17	17	17	11	11	11	11
Texture	Sandy clay loam	Sandy clay loam	Sandy clay loam	Sandy clay loam	Alluvial sandy loam	Alluvial sandy loam	Alluvial sandy loam	Alluvial sandy loam
Bulk density (g cm^−3)	1.43	1.43	1.43	1.43	1.75	1.75	1.75	1.75
Particle density (g cm^−3)	2.67	2.67	2.67	2.67	2.97	2.97	2.97	2.97
pH	8.2	9.1	8.2	9.1	6.53	7.1	6.53	7.1
Electrical conductivity (dSm^−1)	0.47	0.47	0.47	0.47	0.53	0.53	0.53	0.53
Organic carbon (%)	0.45	0.45	0.45	0.45	0.42	0.42	0.42	0.42
Available nitrogen (Kg ha^−1)	247	247	247	247	212	212	212	212
Available phosphorus (Kg ha^−1)	48	48	48	48	22.20	22.20	22.20	22.20
Available potassium (Kg ha^−1)	285	285	285	285	102.06	102.06	102.06	102.06
Available sulfur (Kg ha^−1)	18.6	18.6	18.6	18.6	12.3	12.3	12.3	12.3
Available calcium (Kg ha^−1)	253	253	253	253	128.9	128.9	128.9	128.9
Available magnesium (Kg ha^−1)	198	198	198	198	208	208	208	208
Available sodium (Kg ha^−1)	20	27	20	27	18	25	18	25

* CRRI, Central Rice Research Institute; ICGEB, International Centre for Genetic Engineering and Biotechnology

Table 2. Colony characteristics of different isolates of rhizospheric soil (New Delhi, India) of pots

Rhizospheric Soil (New Delhi, India)	Isolate no.	Form	Color	Elevation	Margin	Size(mm)	Consistency	Motility	Gram staining
WT control	1	Circular	Brown	Low convex	Entire	0.60–0.75	Gummy	+	-ve
	2	Circular	Brown	Convex	Entire	0.60–0.75	Gummy	+	-ve
	3	Circular	Brown	Convex	Entire	0.85–0.90	Gummy	+	-ve
	4	Circular	Fluorescent	Flat	Entire	0.65–0.75	Not gummy	+	-ve
	5	Circular	Off white	Flat	Entire	0.60–0.75	Mucoid	+	-ve
WT+ salt	1	Circular	Brown	Low convex	Entire	0.60–0.75	Gummy	+	-ve
	2	Circular	Brown	Convex	Entire	0.60–0.75	Gummy	+	-ve
	3	Circular	Brown	Convex	Entire	0.85–0.90	Gummy	+	-ve
	4	Circular	Fluorescent	Flat	Entire	0.65–0.75	Not gummy	+	-ve
	5	Circular	Off white	Flat	Entire	0.60–0.75	Mucoid	+	-ve
PDH45 control	1	Circular	Brown	Convex	Entire	0.85–0.90	Gummy	+	-ve
	2	Circular	Brown	Low convex	Entire	0.60–0.75	Gummy	+	-ve
	3	Circular	Fluorescent	Flat	Entire	0.65–0.75	Not gummy	+	-ve
	4	Circular	Off white	Flat	Entire	0.60–0.75	Mucoid	+	-ve
	5	Circular	White	Plicate	Entire	0.95–1.00	Gummy	+	-ve
	6	Circular	Brown	Low convex	Entire	0.60–0.75	Gummy	+	-ve
PDH45+salt	1	Circular	Brown	Convex	Entire	0.85–0.90	Gummy	+	-ve
	2	Circular	Brown	Low convex	Entire	0.60–0.75	Gummy	+	-ve
	3	Circular	Fluorescent	Flat	Entire	0.65–0.75	Not gummy	+	-ve
	4	Circular	Off white	Flat	Entire	0.60–0.75	Mucoid	+	-ve
	5	Circular	White	Plicate	Entire	0.95–1.00	Gummy	+	-ve
	6	Circular	Brown	Low convex	Entire	0.60–0.75	Gummy	+	-ve

Table 3. Colony characteristics of different isolates of rhizospheric soil (Odisha, India) of pots

Rhizospheric Soil (Odisha, India)	Isolate no.	Form	Color	Elevation	Margin	Size(mm)	Consistency	Motility	Gram staining
WT control	1	Circular	White	Plicate	Entire	0.95–1.00	Gummy	+	-ve
	2	Circular	Brown	Convex	Entire	0.85–0.90	Gummy	+	-ve
	3	Circular	Fluorescent	Flat	Entire	0.65–0.75	Not gummy	+	-ve
	4	Circular	Brown	Convex	Entire	0.85–0.90	Gummy	+	-ve
	5	Circular	Off white	Flat	Entire	0.60–0.75	Mucoid	+	-ve
	6	Circular	Brown	Convex	Entire	0.85–0.90	Gummy	+	-ve
	7	Circular	White	Plicate	Entire	0.90–1.00	Gummy	+	-ve
WT+ salt	1	Circular	White	Plicate	Entire	0.95–1.00	Gummy	+	-ve
	2	Circular	Brown	Convex	Entire	0.85–0.90	Gummy	+	-ve
	3	Circular	Fluorescent	Flat	Entire	0.65–0.75	Not gummy	+	-ve
	4	Circular	Brown	Convex	Entire	0.85–0.90	Gummy	+	-ve
	5	Circular	Off white	Flat	Entire	0.60–0.75	Mucoid	+	-ve
	6	Circular	Brown	Convex	Entire	0.85–0.90	Gummy	+	-ve
	7	Circular	White	Plicate	Entire	0.90–1.00	Gummy	+	-ve
PDH45 control	1	Circular	Off white	Flat	Entire	0.60–0.75	Mucoid	+	-ve
	2	Circular	White	Plicate	Entire	0.95–1.00	Gummy	+	-ve
	3	Circular	Fluorescent	Flat	Entire	0.65–0.75	Not gummy	+	-ve
	4	Circular	Brown	Convex	Entire	0.85–0.90	Gummy	+	-ve
	5	Circular	Fluorescent	Flat	Entire	0.65–0.75	Not gummy	+	-ve
	6	Circular	Brown	Low convex	Entire	0.60–0.75	Gummy	+	-ve
PDH45+salt	1	Circular	Off white	Flat	Entire	0.60–0.75	Mucoid	+	-ve
	2	Circular	White	Plicate	Entire	0.95–1.00	Gummy	+	-ve
	3	Circular	Fluorescent	Flat	Entire	0.65–0.75	Not gummy	+	-ve
	4	Circular	Brown	Convex	Entire	0.85–0.90	Gummy	+	-ve
	5	Circular	Fluorescent	Flat	Entire	0.65–0.75	Not gummy	+	-ve
	6	Circular	Brown	Low convex	Entire	0.60–0.75	Gummy	+	-ve

Table 4. Population of nematodes and bacteria in rhizospheric soil of different pots

Rhizospheric soil (New Delhi, India)	Nematodes numbers/pots	Population of bacteria in pots (x 10^5 cfu/g soil)	Rhizospheric soil (Odisha, India)	Nematodes numbers/pots	Population of bacteria in pots (x 10^5 cfu/g soil)
WT control	911.3 ± 1.7^a	51 ± 0.14^a	WT control	845 ± 1.9^c	55 ± 0.16^a
WT+salt	917.4 ± 1.9^a	49 ± 0.12^a	WT+salt	853 ± 1.7^c	53 ± 0.15^a
PDH45 control	915.2 ± 1.4^b	48 ± 0.12^a	PDH45 control	842 ± 1.7^c	52 ± 0.14^a
PDH45+salt	920.3 ± 1.4^b	48 ± 0.13^a	PDH45+salt	847 ± 1.7c	50 ± 0.12^a

Data followed by the same letter in the same row are significantly not different at p < 0.05 as determined by Duncan’s multiple range test (n = 3).

Figure 2. Enzyme activity assay of soils (New Delhi, India). Variations of dehydrogenase (A) acid phosphatase (B), urease (C) and nitrate reductae (D) activities in: (1) WT control (−salt); (2) WT+salt; (3) T1-PDH 45-salt; (4) T1-PDH 45+salt (200 mM NaCl). Data are significantly not different at p < 0.05, n = 3).

Figure 3. Enzyme activity assay of soils (Odisha, India).Variations of dehydrogenase (A) acid phosphatase (B), urease (C) and nitrate reductae (D) activities in: (1) WT control (−salt); (2) T+salt; (3) T1-PDH 45-salt; (4) T1-PDH 45+salt (200 mM NaCl). Data are significantly not different at p < 0.05, n = 3).