Healthy leaf, shoot and root tissues of Eaglewood (Aquilaria crassna Pierre ex Lec.) were collected from the plantations in Nakhonnayok province (14° 7′ 20.60″ N, 101° 4′ 16.23″ E) and Phetchabun province (16° 25′ 27.59″ N, 101° 9′ 42.25″ E) of Thailand, during the period of September-October 2008. The actinomycetes isolates were grown on HT agar at 30 ℃ for 3 weeks. Four-millimeter-diameter agar plugs were cut with a sterile cork borer from the leading edges of colonies, and one such plug was transferred into a 250 ml Erlenmeyer flask containing 100 ml of ISP-2 broth and incubated at 30 ℃ for 3 weeks for preparation of seed culture. One percent of seed culture was propagated in ISP-2 broth supplemented with 0.2% L-tryptophan and incubated in the dark at 30 ℃ with shaking at 120 rev/min for 3 weeks. One percent of seed culture was propagated in peptone water and incubated at 30 ℃ with shaking at 120 rev/min for 3 weeks. One percent of seed culture was propagated in modified Gaus No.1 broth and incubated at 30 ℃ with shaking at 120 rev/min for 3 weeks. Catechol-type siderophores were determined by using Arnow's method (Arnow 1937) and hydroxamate siderophores were determined by using the Csaky test (Csaky 1984).

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).

Healthy leaf, shoot and root tissues of Eaglewood (Aquilaria crassna Pierre ex Lec.) were collected from the plantations in Nakhonnayok province (14° 7′ 20.60″ N, 101° 4′ 16.23″ E) and Phetchabun province (16° 25′ 27.59″ N, 101° 9′ 42.25″ E) of Thailand, during the period of September-October 2008. The actinomycetes isolates were grown on HT agar at 30 ℃ for 3 weeks. Four-millimeter-diameter agar plugs were cut with a sterile cork borer from the leading edges of colonies, and one such plug was transferred into a 250 ml Erlenmeyer flask containing 100 ml of ISP-2 broth and incubated at 30 ℃ for 3 weeks for preparation of seed culture. One percent of seed culture was propagated in ISP-2 broth supplemented with 0.2% L-tryptophan and incubated in the dark at 30 ℃ with shaking at 120 rev/min for 3 weeks. One percent of seed culture was propagated in peptone water and incubated at 30 ℃ with shaking at 120 rev/min for 3 weeks. One percent of seed culture was propagated in modified Gaus No.1 broth and incubated at 30 ℃ with shaking at 120 rev/min for 3 weeks. Catechol-type siderophores were determined by using Arnow's method (Arnow 1937) and hydroxamate siderophores were determined by using the Csaky test (Csaky 1984).

Healthy leaf, shoot and root tissues of Eaglewood (Aquilaria crassna Pierre ex Lec.) were collected from the plantations in Nakhonnayok province (14° 7′ 20.60″ N, 101° 4′ 16.23″ E) and Phetchabun province (16° 25′ 27.59″ N, 101° 9′ 42.25″ E) of Thailand, during the period of September-October 2008. The actinomycetes isolates were grown on HT agar at 30 ℃ for 3 weeks. Four-millimeter-diameter agar plugs were cut with a sterile cork borer from the leading edges of colonies, and one such plug was transferred into a 250 ml Erlenmeyer flask containing 100 ml of ISP-2 broth and incubated at 30 ℃ for 3 weeks for preparation of seed culture. One percent of seed culture was propagated in ISP-2 broth supplemented with 0.2% L-tryptophan and incubated in the dark at 30 ℃ with shaking at 120 rev/min for 3 weeks. One percent of seed culture was propagated in peptone water and incubated at 30 ℃ with shaking at 120 rev/min for 3 weeks. One percent of seed culture was propagated in modified Gaus No.1 broth and incubated at 30 ℃ with shaking at 120 rev/min for 3 weeks. Catechol-type siderophores were determined by using Arnow's method (Arnow 1937) and hydroxamate siderophores were determined by using the Csaky test (Csaky 1984).

Healthy leaf, shoot and root tissues of Eaglewood (Aquilaria crassna Pierre ex Lec.) were collected from the plantations in Nakhonnayok province (14° 7′ 20.60″ N, 101° 4′ 16.23″ E) and Phetchabun province (16° 25′ 27.59″ N, 101° 9′ 42.25″ E) of Thailand, during the period of September-October 2008. The actinomycetes isolates were grown on HT agar at 30 ℃ for 3 weeks. Four-millimeter-diameter agar plugs were cut with a sterile cork borer from the leading edges of colonies, and one such plug was transferred into a 250 ml Erlenmeyer flask containing 100 ml of ISP-2 broth and incubated at 30 ℃ for 3 weeks for preparation of seed culture. One percent of seed culture was propagated in ISP-2 broth supplemented with 0.2% L-tryptophan and incubated in the dark at 30 ℃ with shaking at 120 rev/min for 3 weeks. One percent of seed culture was propagated in peptone water and incubated at 30 ℃ with shaking at 120 rev/min for 3 weeks. One percent of seed culture was propagated in modified Gaus No.1 broth and incubated at 30 ℃ with shaking at 120 rev/min for 3 weeks. Catechol-type siderophores were determined by using Arnow's method (Arnow 1937) and hydroxamate siderophores were determined by using the Csaky test (Csaky 1984).

Healthy leaf, shoot and root tissues of Eaglewood (Aquilaria crassna Pierre ex Lec.) were collected from the plantations in Nakhonnayok province (14° 7′ 20.60″ N, 101° 4′ 16.23″ E) and Phetchabun province (16° 25′ 27.59″ N, 101° 9′ 42.25″ E) of Thailand, during the period of September-October 2008. The actinomycetes isolates were grown on HT agar at 30 ℃ for 3 weeks. Four-millimeter-diameter agar plugs were cut with a sterile cork borer from the leading edges of colonies, and one such plug was transferred into a 250 ml Erlenmeyer flask containing 100 ml of ISP-2 broth and incubated at 30 ℃ for 3 weeks for preparation of seed culture. One percent of seed culture was propagated in ISP-2 broth supplemented with 0.2% L-tryptophan and incubated in the dark at 30 ℃ with shaking at 120 rev/min for 3 weeks. One percent of seed culture was propagated in peptone water and incubated at 30 ℃ with shaking at 120 rev/min for 3 weeks. One percent of seed culture was propagated in modified Gaus No.1 broth and incubated at 30 ℃ with shaking at 120 rev/min for 3 weeks. Catechol-type siderophores were determined by using Arnow's method (Arnow 1937) and hydroxamate siderophores were determined by using the Csaky test (Csaky 1984).

Healthy leaf, shoot and root tissues of Eaglewood (Aquilaria crassna Pierre ex Lec.) were collected from the plantations in Nakhonnayok province (14° 7′ 20.60″ N, 101° 4′ 16.23″ E) and Phetchabun province (16° 25′ 27.59″ N, 101° 9′ 42.25″ E) of Thailand, during the period of September-October 2008. The actinomycetes isolates were grown on HT agar at 30 ℃ for 3 weeks. Four-millimeter-diameter agar plugs were cut with a sterile cork borer from the leading edges of colonies, and one such plug was transferred into a 250 ml Erlenmeyer flask containing 100 ml of ISP-2 broth and incubated at 30 ℃ for 3 weeks for preparation of seed culture. One percent of seed culture was propagated in ISP-2 broth supplemented with 0.2% L-tryptophan and incubated in the dark at 30 ℃ with shaking at 120 rev/min for 3 weeks. One percent of seed culture was propagated in peptone water and incubated at 30 ℃ with shaking at 120 rev/min for 3 weeks. One percent of seed culture was propagated in modified Gaus No.1 broth and incubated at 30 ℃ with shaking at 120 rev/min for 3 weeks. Catechol-type siderophores were determined by using Arnow's method (Arnow 1937) and hydroxamate siderophores were determined by using the Csaky test (Csaky 1984).

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).

Healthy leaf, shoot and root tissues of Eaglewood (Aquilaria crassna Pierre ex Lec.) were collected from the plantations in Nakhonnayok province (14° 7′ 20.60″ N, 101° 4′ 16.23″ E) and Phetchabun province (16° 25′ 27.59″ N, 101° 9′ 42.25″ E) of Thailand, during the period of September-October 2008. The actinomycetes isolates were grown on HT agar at 30 ℃ for 3 weeks. Four-millimeter-diameter agar plugs were cut with a sterile cork borer from the leading edges of colonies, and one such plug was transferred into a 250 ml Erlenmeyer flask containing 100 ml of ISP-2 broth and incubated at 30 ℃ for 3 weeks for preparation of seed culture. One percent of seed culture was propagated in ISP-2 broth supplemented with 0.2% L-tryptophan and incubated in the dark at 30 ℃ with shaking at 120 rev/min for 3 weeks. One percent of seed culture was propagated in peptone water and incubated at 30 ℃ with shaking at 120 rev/min for 3 weeks. One percent of seed culture was propagated in modified Gaus No.1 broth and incubated at 30 ℃ with shaking at 120 rev/min for 3 weeks. Catechol-type siderophores were determined by using Arnow's method (Arnow 1937) and hydroxamate siderophores were determined by using the Csaky test (Csaky 1984).

Healthy leaf, shoot and root tissues of Eaglewood (Aquilaria crassna Pierre ex Lec.) were collected from the plantations in Nakhonnayok province (14° 7′ 20.60″ N, 101° 4′ 16.23″ E) and Phetchabun province (16° 25′ 27.59″ N, 101° 9′ 42.25″ E) of Thailand, during the period of September-October 2008. The actinomycetes isolates were grown on HT agar at 30 ℃ for 3 weeks. Four-millimeter-diameter agar plugs were cut with a sterile cork borer from the leading edges of colonies, and one such plug was transferred into a 250 ml Erlenmeyer flask containing 100 ml of ISP-2 broth and incubated at 30 ℃ for 3 weeks for preparation of seed culture. One percent of seed culture was propagated in ISP-2 broth supplemented with 0.2% L-tryptophan and incubated in the dark at 30 ℃ with shaking at 120 rev/min for 3 weeks. One percent of seed culture was propagated in peptone water and incubated at 30 ℃ with shaking at 120 rev/min for 3 weeks. One percent of seed culture was propagated in modified Gaus No.1 broth and incubated at 30 ℃ with shaking at 120 rev/min for 3 weeks. Catechol-type siderophores were determined by using Arnow's method (Arnow 1937) and hydroxamate siderophores were determined by using the Csaky test (Csaky 1984).

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).