Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).

Soil samples were collected from 16 medicinal plant rhizospheres in Lumphun Province. Indole acetic acid (IAA) production: The actinomycete discs (8 mm), grown on yeast malt extract agar (YM) incubated at 28 ℃ for 5 days, were inoculated into 5 ml YM broth containing 0.2% L-tryptophan and incubated at 28 ℃ with shaking at 125 rev/min for 7 days. Cultures were centrifuged at 11,000 rev/min for 15 min. One milliliter of the supernatant was mixed with 2 ml of Salkowski reagent. Appearance of a pink color indicated IAA production. Optical density (OD) was read at 530 nm using a spectrophotometer. The level of IAA produced was estimated by comparison with an IAA standard. The actinomycete discs (8 mm), grown on YM agar incubated at 28 ℃ for 5 days were inoculated on CAS-substrates with modified Gaus No.1 medium (MGs) and incubated at 28 ℃ for 10 days. The colonies with orange zones were considered as siderophore-producing isolates. The functional groups of the siderophores were determined. The active isolates (width of orange zone on CAS plate >20 mm) were cultured on modified Gaus No.1 broth and incubated at 28 ℃ with shaking at 125 rpm for 10 days. Catechol-type siderophores were estimated by Arnow's method (Arnow 1937) and hydroxamate siderophores were estimated by the Csaky test (Csaky 1948).