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Life Science Research and Sustainable Development ISBN: 978-98-84663-33-9

plant. Crop rotation with legumes has been recognized to increase soil fertility and agricultural
productivity (Cheng, 2008). Santi1 et al., (2013) studied b iological nitrogen fixation in non-
legume plants. Endophytic bacteria can influence plant growth & productivity through Nitrogen
fixation. Conceptually, plant growth promoting endophytic bacteria may affect plant growth
either directly or indirectly (Sansanwal et al., 2017). Large and diverse populations of N2-fixing
bacteria are associated with sugarcane.
Endophytic bacteria establish in between and within the spaces of all plant parts and not
causing any plant disease. They create array of relationship include mutualism, cannibalistic,
commensalistic and trophobiotic in nature. Endophytic bacteria play a major role in developing
plant growth enhancement, phytoremediation, phosphate solubilization, nitrogen fixation,
modulation of plant metabolism and phytohormone signaling. There is an increased interest in
the use of endophytes for their agricultural applications that promote plant growth under cold,
drought or contaminated soil structure conditions or induce disease resistance in plants
(Muthukumar et al., 2018). Endophytic bacteria are alternative to agrochemicals (fertilizers and
pesticides) in developing environment friendly agriculture (Adeleke and Babolola, 2021).
Therefore, e ndophytic bacteria play an important role in microbial ecology, associating
environmental factors, and their roles that contribute to their effectiveness in promoting plant
growth for maximum agricultural crop productivity was highlighted (Adeleke and Babolola
2021). A. diazotrophicus is a nitrogen-fixing endophytic bacterium, originally isolated from
sugarcane. Its colonizing ability was evaluated in field of agriculture to promote the growth and
development of crop plant. A preliminary study regarding contributions of the bacterial
endophyte A. diazotrophicus to sugarcane nutrition was reported by Sevilla et al., (1998). A.
diazotrophicus was found mainly inside cortical cells of stems and inside xylem vessels. No L-
glucuronidase activity was observed in non-inoculated plants. A. diazotrophicus is able to increase
nutrient supply, soil fertility and crop growth of sugarcane. The study of A. diazotrophicus will
be useful for further researchers and it will be better alternative for chemical fertilizers. A.
diazotrophicus colonizing the root intercellular spaces and the interior of root epidermal cells. They
proposed that A. diazotrophicus could be distributed from the base of the stem to other organs via
stem xylem vessels, since they also detected xylem colonization in the basal region of the stalk in
non-inoculated sugarcane plants (Dong et al., 1997). Hence during the present investigation
report of A. diazotrophicus was collected from sugarcane from Rahuri taluka of Ahemednagar
district

MATERIALS & METHODS
a) Collection of bacterial samples: Rhizosphere samples were collected from 16 different
locations of Rahuri taluka of Ahmednagar district in sterile zipped locked polythene bags. Those
samples were brought to the laboratory and kept at 4 C for further investigations. Soil pH was
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calculated using pH meter, while Water Holding Capacity (WHC) was determined as described
(Kalra, 1995).
b) Isolation of bacterial samples: One gram of soil was suspended in 10 ml distilled water to
prepare soil suspension. It was inoculated on specific Acetobater manitol agar media
(Hi-Media) and incubated at 25±2 C for 48 Hrs. which allow only the growth of A. diazotrophicus.
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c) Morphological Characterization: Confirmation of the bacteria was done by relevant
morphological characterization (Phalke et al., 2017). Growth of colonies was observed after 48
Hrs. Morphology characterization of bacterial cell was studied in respect to cell size, shape and
gram staining. While Colony morphology was studied in respect to color, shape, size, appearance

https://jesjalna.org/Zoology-Publications/index.html 22 Department of Zoology, J. E. S. College, Jalna