A PRELIMINARY STUDY ON THE STRESS RESISTANCE OF RHIZOBIA ISOLATED FROM AMMOPIPTANTHUS MONGOLICUS

doi:10.17521/cjpe.2006.0020

Abstract

Abstract:

Ammopiptanthus mongolicus is an endangered evergreen broad-leaf species in the northwest desert zone of China. Shapotou, Alashanzuoqi, Dengkou and Wulatehouqi were defined as research regions based on soil, water and other ecological factors. Nodules of A. mongolicus were collected during the last twenty-days of April, which was the flowering period of the host, and their characteristics were studied. The resistance of rhizobia isolated from A. mongolicus also was studied in relation to environmental factors of the distribution areas. Seventeen rhizobia strains were isolated from A. mongolicus. It was found that nodules had various attachment modes, sizes, shapes and colors, which were related to differences of their environment, of which water may be the most important determinant. Several biochemical characteristics were determined, including resistance to salt, acid-alkali, temperature variation and intrinsic antibiotics. The results indicated that 64.7% strains could tolerate NaCl stress at 3% concentration, 94.1% strains could grow at a range of pH from 5-11, and all strains could grow after being exposed to 60 ℃ for 10 min. Differences in resistance to different intrinsic antibiotics existed among strain ZW₄, and WH₄¹ had high a resistance to different intrinsic antibiotics. Rhizobia strains from Dengkou had higher resistance to acid-alkali conditions and temperature. These results indicated that rhizobia strains isolated from A. mongolicus were highly resistant to stresses. However, there were differences among strains in their resistance to stresses, which might be related to adaptations of rhizobia to the diverse landscapes in different regions. Resistances of rhizobia strains isolated from accompanying plants, for example, Caragana corshinskii, Caragana intermedia and Oxytropis aciphylla, also were studied, and the results indicated that they also were highly resistant to stresses similar to the rhizobia strains isolated from A. mongolicus. These results indicated that the symbiosis between rhizobia and legumes was influenced by their environment. The high resistance of A. mongolicus may be related to the high resistance of its rhizobia, and that the symbiotic relation was beneficial to the development and maintenance of its community in diverse landscapes.

Key words: Ammopiptanthus mongolicus, Rhizobia, Resistance, Eco-environment, High resistance

HE Heng-Bin, JIA Kun-Feng, JIA Gui-Xia, DING Qiong. A PRELIMINARY STUDY ON THE STRESS RESISTANCE OF RHIZOBIA ISOLATED FROM AMMOPIPTANTHUS MONGOLICUS[J]. Chin J Plant Ecol, 2006, 30(1): 140-146.

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URL: https://www.plant-ecology.com/EN/10.17521/cjpe.2006.0020

https://www.plant-ecology.com/EN/Y2006/V30/I1/140

Figures/Tables 5

Table 1 Sampling places of the experimental strains and the source of the reference strain

菌株号Strains number	宿主名Host	采集地点Sampling places	地形及土壤Terrain and soil
$DK 1 1$	沙冬青 Ammopiptanthus mongolicus	磴口Dengkou	平坦风蚀沙地,风沙土加粘土Wind erosion moving sand, windy sand soil and clay
$DK 1 2$	沙冬青A. mongolicus	磴口Dengkou	平坦风蚀沙地,风沙土加粘土Wind erosion moving sand, windy sand soil and clay
DK₄	沙冬青A. mongolicus	磴口Dengkou	盐渍化滩地,粗砾质风沙土Saline-alkaline land, windy stone-sand soil
DK₅	沙冬青A. mongolicus	磴口Dengkou	洪水冲积沟滩地,粉尘风沙土Land caused by seasonal floods, windy sand soil
DK₆	沙冬青A. mongolicus	磴口Dengkou	洪水冲积沟滩地,粉尘风沙土Land caused by seasonal floods, windy sand soil
DK₈	沙冬青A. mongolicus	磴口Dengkou	盐渍化滩地,粗砾质风沙土Saline-alkaline land, windy stone-sand soil
ZW₄	沙冬青A. mongolicus	中卫沙坡头Shapotou	低山坡地,红土质灰棕漠土Hillside, grey brown desert soil
ZW₇	沙冬青A. mongolicus	中卫沙坡头Shapotou	低山坡地,红土质灰棕漠土Hillside, grey brown desert soil
ZW₈	沙冬青A. mongolicus	中卫沙坡头Shapotou	低山坡地,红土质灰棕漠土Hillside, grey brown desert soil
$WH 1 1$	沙冬青A. mongolicus	乌拉特后旗Wulatehouqi	平坦石质滩地及沙丘,风沙土和红土质灰棕漠土Flood land and dune, windy sand soil and grey brown desert soil
$WH 1 2$	沙冬青A. mongolicus	乌拉特后旗Wulatehouqi	平坦石质滩地及沙丘,风沙土和红土质灰棕漠土Flood land and dune, windy sand soil and grey brown desert soil
$WH 1 3$	沙冬青A. mongolicus	乌拉特后旗Wulatehouqi	平坦石质滩地及沙丘,风沙土和红土质灰棕漠土Flood land and dune, windy sand soil and grey brown desert soil
$WH 4 1$	沙冬青A. mongolicus	乌拉特后旗Wulatehouqi	平坦石质滩地及沙丘,风沙土和红土质灰棕漠土Flood land and dune, windy sand soil and grey brown desert soil
$WH 4 2$	沙冬青A. mongolicus	乌拉特后旗Wulatehouqi	平坦石质滩地及沙丘,风沙土和红土质灰棕漠土Flood land and dune, windy sand soil and grey brown desert soil
WH₆	沙冬青A. mongolicus	乌拉特后旗Wulatehouqi	平坦石质滩地及沙丘,风沙土和红土质灰棕漠土Flood land and dune, windy sand soil and grey brown desert soil
AZ₁	沙冬青A. mongolicus	阿拉善左旗Alashanzuoqi	低山残塬,红土质灰棕漠土Loess hill, grey brown desert soil
AZ₂	沙冬青A. mongolicus	阿拉善左旗Alashanzuoqi	残存河床,风沙土Riverbed, windy sand soil
CAN(参比菌株Reference strain)	沙冬青A. mongolicus	磴口Dengkou	购于中国农业大学Bought from China Agriculture Universituy
WHn	柠条Caragana korshinskii	乌拉特后旗Wulatehouqi	平坦石质滩地及沙丘,风沙土和红土质灰棕漠土Flood land and dune, windy sand soil and grey brown desert soil
WHj	锦鸡儿C. intermedia	乌拉特后旗Wulatehouqi	平坦石质滩地及沙丘,风沙土和红土质灰棕漠土Flood land and dune, windy sand soil and grey brown desert soil
ZWn	柠条C. korshinskii	中卫沙坡头Shapotou	低山坡地,红土质灰棕漠土Hillside, grey brown desert soil
WHm	猫头刺Oxytropis aciphylla	乌拉特后旗Wulatehouqi	平坦石质滩地及沙丘,风沙土和红土质灰棕漠土Flood land and dune, windy sand soil and grey brown desert soil

Table 1 Sampling places of the experimental strains and the source of the reference strain

菌株号Strains number	宿主名Host	采集地点Sampling places	地形及土壤Terrain and soil
$DK 1 1$	沙冬青 Ammopiptanthus mongolicus	磴口Dengkou	平坦风蚀沙地,风沙土加粘土Wind erosion moving sand, windy sand soil and clay
$DK 1 2$	沙冬青A. mongolicus	磴口Dengkou	平坦风蚀沙地,风沙土加粘土Wind erosion moving sand, windy sand soil and clay
DK₄	沙冬青A. mongolicus	磴口Dengkou	盐渍化滩地,粗砾质风沙土Saline-alkaline land, windy stone-sand soil
DK₅	沙冬青A. mongolicus	磴口Dengkou	洪水冲积沟滩地,粉尘风沙土Land caused by seasonal floods, windy sand soil
DK₆	沙冬青A. mongolicus	磴口Dengkou	洪水冲积沟滩地,粉尘风沙土Land caused by seasonal floods, windy sand soil
DK₈	沙冬青A. mongolicus	磴口Dengkou	盐渍化滩地,粗砾质风沙土Saline-alkaline land, windy stone-sand soil
ZW₄	沙冬青A. mongolicus	中卫沙坡头Shapotou	低山坡地,红土质灰棕漠土Hillside, grey brown desert soil
ZW₇	沙冬青A. mongolicus	中卫沙坡头Shapotou	低山坡地,红土质灰棕漠土Hillside, grey brown desert soil
ZW₈	沙冬青A. mongolicus	中卫沙坡头Shapotou	低山坡地,红土质灰棕漠土Hillside, grey brown desert soil
$WH 1 1$	沙冬青A. mongolicus	乌拉特后旗Wulatehouqi	平坦石质滩地及沙丘,风沙土和红土质灰棕漠土Flood land and dune, windy sand soil and grey brown desert soil
$WH 1 2$	沙冬青A. mongolicus	乌拉特后旗Wulatehouqi	平坦石质滩地及沙丘,风沙土和红土质灰棕漠土Flood land and dune, windy sand soil and grey brown desert soil
$WH 1 3$	沙冬青A. mongolicus	乌拉特后旗Wulatehouqi	平坦石质滩地及沙丘,风沙土和红土质灰棕漠土Flood land and dune, windy sand soil and grey brown desert soil
$WH 4 1$	沙冬青A. mongolicus	乌拉特后旗Wulatehouqi	平坦石质滩地及沙丘,风沙土和红土质灰棕漠土Flood land and dune, windy sand soil and grey brown desert soil
$WH 4 2$	沙冬青A. mongolicus	乌拉特后旗Wulatehouqi	平坦石质滩地及沙丘,风沙土和红土质灰棕漠土Flood land and dune, windy sand soil and grey brown desert soil
WH₆	沙冬青A. mongolicus	乌拉特后旗Wulatehouqi	平坦石质滩地及沙丘,风沙土和红土质灰棕漠土Flood land and dune, windy sand soil and grey brown desert soil
AZ₁	沙冬青A. mongolicus	阿拉善左旗Alashanzuoqi	低山残塬,红土质灰棕漠土Loess hill, grey brown desert soil
AZ₂	沙冬青A. mongolicus	阿拉善左旗Alashanzuoqi	残存河床,风沙土Riverbed, windy sand soil
CAN(参比菌株Reference strain)	沙冬青A. mongolicus	磴口Dengkou	购于中国农业大学Bought from China Agriculture Universituy
WHn	柠条Caragana korshinskii	乌拉特后旗Wulatehouqi	平坦石质滩地及沙丘,风沙土和红土质灰棕漠土Flood land and dune, windy sand soil and grey brown desert soil
WHj	锦鸡儿C. intermedia	乌拉特后旗Wulatehouqi	平坦石质滩地及沙丘,风沙土和红土质灰棕漠土Flood land and dune, windy sand soil and grey brown desert soil
ZWn	柠条C. korshinskii	中卫沙坡头Shapotou	低山坡地,红土质灰棕漠土Hillside, grey brown desert soil
WHm	猫头刺Oxytropis aciphylla	乌拉特后旗Wulatehouqi	平坦石质滩地及沙丘,风沙土和红土质灰棕漠土Flood land and dune, windy sand soil and grey brown desert soil

Table 2 Effects of NaCl on growth of rhizobium

菌株 Strains	NaCl (%)
菌株 Strains	1	2	3	4	5	6	7
$DK 1 1$	+	+	+	-	-	-	-
$DK 1 2$	+	+	-	-	-	-	-
DK₄	+	+	+	+	+	+	-
DK₅	+	-	-	-	-	-	-
DK₆	+	-	-	-	-	-	-
DK₈	+	+	+	+	+	+	+
ZW₄	+	+	-	-	-	-	-
ZW₇	+	+	+	+	+	-	-
ZW₈	+	+	+	+	+	+	+
$WH 1 1$	+	-	-	-	-	-	-
$WH 1 2$	+	-	-	-	-	-	-
$WH 1 3$	-	-	-	-	-	-	-
$WH 4 1$	+	-	-	-	-	-	-
$WH 4 2$	+	+	+	+	-	-	-
WH₆	+	+	+	-	-	-	-
AZ₁	-	-	-	-	-	-	-
AZ₂	+	+	+	+	+	+	+
CAN	+	+	+	-	-	-	-
WHn	+	+	+	+	+	+	-
WHj	+	+	+	+	+	+	-
ZWn	-	-	-	-	-	-	-
WHm	+	+	+	+	+	+	+

Table 2 Effects of NaCl on growth of rhizobium

菌株 Strains	NaCl (%)
菌株 Strains	1	2	3	4	5	6	7
$DK 1 1$	+	+	+	-	-	-	-
$DK 1 2$	+	+	-	-	-	-	-
DK₄	+	+	+	+	+	+	-
DK₅	+	-	-	-	-	-	-
DK₆	+	-	-	-	-	-	-
DK₈	+	+	+	+	+	+	+
ZW₄	+	+	-	-	-	-	-
ZW₇	+	+	+	+	+	-	-
ZW₈	+	+	+	+	+	+	+
$WH 1 1$	+	-	-	-	-	-	-
$WH 1 2$	+	-	-	-	-	-	-
$WH 1 3$	-	-	-	-	-	-	-
$WH 4 1$	+	-	-	-	-	-	-
$WH 4 2$	+	+	+	+	-	-	-
WH₆	+	+	+	-	-	-	-
AZ₁	-	-	-	-	-	-	-
AZ₂	+	+	+	+	+	+	+
CAN	+	+	+	-	-	-	-
WHn	+	+	+	+	+	+	-
WHj	+	+	+	+	+	+	-
ZWn	-	-	-	-	-	-	-
WHm	+	+	+	+	+	+	+

Table 3 Effects of pH on growth of rhizobium

菌株 Strains	pH
菌株 Strains	3	4	5	6	8	9	10	11	12	13
$DK 1 1$	-	+	+	+	+	+	+	+	-	-
$DK 1 2$	-	+	+	+	+	+	+	+	-	-
DK₄	-	-	-	+	+	+	+	+	+	-
DK₅	-	-	+	+	+	+	+	+	-	-
DK₆	-	+	+	+	+	+	+	+	+	-
DK₈	-	+	+	+	+	+	+	+	+	-
ZW₄	-	-	+	+	+	+	+	+	+	-
ZW₇	-	-	+	+	+	+	+	+	-	-
ZW₈	-	-	+	+	+	+	+	+	+	-
$WH 1 1$	-	-	+	+	+	+	+	+	-	-
$WH 1 2$	-	+	+	+	+	+	+	+	-	-
$WH 1 3$	-	+	+	+	+	+	+	+	-	-
$WH 4 1$	-	+	+	+	+	+	+	+	-	-
$WH 4 2$	-	-	+	+	+	+	+	+	+	-
WH₆	-	-	+	+	+	+	+	+	-	-
AZ₁	-	-	+	+	+	+	+	+	-	-
AZ₂	-	+	+	+	+	+	+	+	+	-
CAN	-	-	-	-	+	+	+	+	-	-
WHn	-	-	-	-	+	+	+	+	+	-
WHj	-	+	+	+	+	+	+	+	+	-
ZWn	-	-	+	+	+	+	+	+	-	-
WHm	-	+	+	+	+	+	+	+	+	-

Table 3 Effects of pH on growth of rhizobium

菌株 Strains	pH
菌株 Strains	3	4	5	6	8	9	10	11	12	13
$DK 1 1$	-	+	+	+	+	+	+	+	-	-
$DK 1 2$	-	+	+	+	+	+	+	+	-	-
DK₄	-	-	-	+	+	+	+	+	+	-
DK₅	-	-	+	+	+	+	+	+	-	-
DK₆	-	+	+	+	+	+	+	+	+	-
DK₈	-	+	+	+	+	+	+	+	+	-
ZW₄	-	-	+	+	+	+	+	+	+	-
ZW₇	-	-	+	+	+	+	+	+	-	-
ZW₈	-	-	+	+	+	+	+	+	+	-
$WH 1 1$	-	-	+	+	+	+	+	+	-	-
$WH 1 2$	-	+	+	+	+	+	+	+	-	-
$WH 1 3$	-	+	+	+	+	+	+	+	-	-
$WH 4 1$	-	+	+	+	+	+	+	+	-	-
$WH 4 2$	-	-	+	+	+	+	+	+	+	-
WH₆	-	-	+	+	+	+	+	+	-	-
AZ₁	-	-	+	+	+	+	+	+	-	-
AZ₂	-	+	+	+	+	+	+	+	+	-
CAN	-	-	-	-	+	+	+	+	-	-
WHn	-	-	-	-	+	+	+	+	+	-
WHj	-	+	+	+	+	+	+	+	+	-
ZWn	-	-	+	+	+	+	+	+	-	-
WHm	-	+	+	+	+	+	+	+	+	-

Table 4 Effects of temperature on growth of rhizobium

菌株 Strains	温度 Temperature (℃)
菌株 Strains	4	12	20	37	45	50(10 min)	60(10 min)
$DK 1 1$	-	+	+	+	-	+	+
$DK 1 2$	-	+	+	+	-	+	+
DK₄	+	+	+	+	+	+	+
DK₅	+	+	+	-	-	+	+
DK₆	-	+	+	+	+	+	+
DK₈	-	+	+	+	+	+	+
ZW₄	+	+	+	+	-	+	+
ZW₇	-	+	+	+	-	+	+
ZW₈	+	+	+	+	+	+	+
$WH 1 1$	-	+	+	+	-	+	+
$WH 1 2$	-	+	+	+	-	+	+
$WH 1 3$	-	-	+	+	-	+	+
$WH 4 1$	-	+	+	+	-	+	+
$WH 4 2$	-	+	+	+	-	+	+
WH₆	-	+	+	+	-	+	+
AZ₁	+	+	+	+	-	+	+
AZ₂	+	+	+	+	-	+	+
CAN	+	+	+	+	-	+	+
WHn	-	+	+	+	-	+	+
WHj	-	+	+	+	-	+	+
ZWn	-	-	+	-	-	+	+
WHm	-	-	+	+	+	+	+

Table 4 Effects of temperature on growth of rhizobium

菌株 Strains	温度 Temperature (℃)
菌株 Strains	4	12	20	37	45	50(10 min)	60(10 min)
$DK 1 1$	-	+	+	+	-	+	+
$DK 1 2$	-	+	+	+	-	+	+
DK₄	+	+	+	+	+	+	+
DK₅	+	+	+	-	-	+	+
DK₆	-	+	+	+	+	+	+
DK₈	-	+	+	+	+	+	+
ZW₄	+	+	+	+	-	+	+
ZW₇	-	+	+	+	-	+	+
ZW₈	+	+	+	+	+	+	+
$WH 1 1$	-	+	+	+	-	+	+
$WH 1 2$	-	+	+	+	-	+	+
$WH 1 3$	-	-	+	+	-	+	+
$WH 4 1$	-	+	+	+	-	+	+
$WH 4 2$	-	+	+	+	-	+	+
WH₆	-	+	+	+	-	+	+
AZ₁	+	+	+	+	-	+	+
AZ₂	+	+	+	+	-	+	+
CAN	+	+	+	+	-	+	+
WHn	-	+	+	+	-	+	+
WHj	-	+	+	+	-	+	+
ZWn	-	-	+	-	-	+	+
WHm	-	-	+	+	+	+	+

Table 5 The resistance of Ammopiptanthus mongolicus thtzobia to antibioties

菌株 Strains	Km(μg·ml^-1)				Amp(μg·ml^-1)				Rif(μg·ml^-1)				Cm(μg·ml^-1)
菌株 Strains	5	50	100	300	5	50	100	300	5	50	100	300	5	50	100	300
$DK 1 1$	+	+	-	-	+	+	+	+	+	-	-	-	+	+	+	+
$DK 1 2$	+	+	+	-	+	+	+	+	+	-	-	-	+	+	+	+
DK₄	-	-	-	-	+	-	-	-	-	-	-	-	+	-	-	-
DK₅	+	+	-	-	+	+	+	-	-	-	-	-	+	+	-
DK₆	-	-	-	-	-	-	-	-	-	-	-	-	+	-	-	-
DK₈	-	-	-	-	+	-	-	-	-	-	-	-	-	-	-	-
ZW₄	+	+	+	-	+	+	+	+	+	+	+	-	+	+	+	+
ZW₇	+	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-
ZW₈	-	-	-	-	-	-	-	-	-	-	-	-	+	-	-	-
$WH 1 1$	-	-	-	-	+	-	-	-	+	-	-	-	+	+	+	+
$WH 1 2$	+	-	-	-	+	-	-	-	-	-	-	-	+	+	+	+
$WH 1 3$	+	+	-	-	+	+	+	+	-	-	-	-	+	+	+	+
$WH 4 1$	+	+	+	-	+	+	+	+	+	+	-	-	+	+	+	+
$WH 4 2$	-	-	-	-	+	+	+	+	-	-	-	-	+	-	-	-
WH₆	+	+	-	-	+	+	+	+	+	-	-	-	+	+	+	-
AZ₁	+	+	-	-	+	-	-	-	-	-	-	-	+	-	-	-
AZ₂	+	-	-	-	+	+	+	+	+	-	-	-	+	+	+	+
CAN	+	-	-	-	+	+	+	+	-	-	-	-	+	+	+	+
WHn	-	-	-	-	+	-	-	-	-	-	-	-	+	-	-	-
WHj	+	-	-	-	+	+	-	-	-	-	-	-	+	+	+	+
ZWn	-	-	-	-	-	-	-	-	-	-	-	-	+	-	-	-
WHm	-	-	-	-	+	-	-	-	-	-	-	-	-	-	-	-

Table 5 The resistance of Ammopiptanthus mongolicus thtzobia to antibioties

菌株 Strains	Km(μg·ml^-1)				Amp(μg·ml^-1)				Rif(μg·ml^-1)				Cm(μg·ml^-1)
菌株 Strains	5	50	100	300	5	50	100	300	5	50	100	300	5	50	100	300
$DK 1 1$	+	+	-	-	+	+	+	+	+	-	-	-	+	+	+	+
$DK 1 2$	+	+	+	-	+	+	+	+	+	-	-	-	+	+	+	+
DK₄	-	-	-	-	+	-	-	-	-	-	-	-	+	-	-	-
DK₅	+	+	-	-	+	+	+	-	-	-	-	-	+	+	-
DK₆	-	-	-	-	-	-	-	-	-	-	-	-	+	-	-	-
DK₈	-	-	-	-	+	-	-	-	-	-	-	-	-	-	-	-
ZW₄	+	+	+	-	+	+	+	+	+	+	+	-	+	+	+	+
ZW₇	+	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-
ZW₈	-	-	-	-	-	-	-	-	-	-	-	-	+	-	-	-
$WH 1 1$	-	-	-	-	+	-	-	-	+	-	-	-	+	+	+	+
$WH 1 2$	+	-	-	-	+	-	-	-	-	-	-	-	+	+	+	+
$WH 1 3$	+	+	-	-	+	+	+	+	-	-	-	-	+	+	+	+
$WH 4 1$	+	+	+	-	+	+	+	+	+	+	-	-	+	+	+	+
$WH 4 2$	-	-	-	-	+	+	+	+	-	-	-	-	+	-	-	-
WH₆	+	+	-	-	+	+	+	+	+	-	-	-	+	+	+	-
AZ₁	+	+	-	-	+	-	-	-	-	-	-	-	+	-	-	-
AZ₂	+	-	-	-	+	+	+	+	+	-	-	-	+	+	+	+
CAN	+	-	-	-	+	+	+	+	-	-	-	-	+	+	+	+
WHn	-	-	-	-	+	-	-	-	-	-	-	-	+	-	-	-
WHj	+	-	-	-	+	+	-	-	-	-	-	-	+	+	+	+
ZWn	-	-	-	-	-	-	-	-	-	-	-	-	+	-	-	-
WHm	-	-	-	-	+	-	-	-	-	-	-	-	-	-	-	-

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