गुरुवार, 28 फ़रवरी 2013

plant sciences / FUSARIUM OXYSPORUM








289
N
S
ave Nature to
S
urvive
6(1) : 289-291, 2011
www.thebioscan.in
EFFECT OF DIFFERENT pH LEVELS ON THE GROWTH AND
SPORULATION OF
FUSARIUM OXYSPORUM
SCHLECHT. F. SP.
LENTIS
(VASUDEVA AND SRINIVASAN) THE CAUSAL ORGANISM
OF WILT DISEASE OF LENTIL
HIMANSHU BHUSHAN JARUHAR* AND AJAY PRASAD
1
Department of Botany, S. P. D. College, Garhwa - 822 114, Jharkhand
1
Department of Botany, S. S. J. S. N. College, Garhwa - 822 114, Jharkhand
E-mail: hbjaruhar@gmail.com
INTRODUCTION
Fusarium oxysporum
Schlecht f sp.
lentis
(Vasudeva and
Srinivasan) causes a serious wilt disease in lentil (
Lens esculenta
Moench.) which is an important pulse crop of Palamu
commissionary (23º52’North latitude and 84º17’East
longitude). Due to this disease there is huge loss of the yield in
lentil. Vasudeva and Srinivasan (1952) have reported that Wilt
disease of lentil caused by
Fusarium
spp
.
is one of the serious
disease and it causes huge loss of the standing crop throughout
the world. The extent of the damage to the crop due to the
disease ranges from 20-24% annually, (Saxena
and
Johansen,
1990 and Ali, 2007). There were various reports that indicate
Fusarium
spp grow at different pH levels for growth and
sporulation (Wilson, 1946; Srobar, 1978; Prasad
et al
., 1992;
Souramma and Singh, 2004; Groenewald, 2005). The
pathogen is soil born and infects the host during seedling
stage through root and blocks the vascular system (Vasudeva
and Srinivasan, 1952). For the successful cultivation of the
lentil it is necessary to investigate the physiology of the fungus.
Therefore, effect of different pH level on the growth and
sporulation of
Fusarium oxysporum
Schlecht. f. sp.
lentis
was
undertaken.
MATERIALS AND METHODS
The fungus was isolated from the infected plant of lentil (
Lens
esculenta
Moench). Monospore culture as described by
Prasad and Chaudhary (1966, 1967) was employed in the
present study. From the culture of the isolates, pure culture
was obtained using 10
-5
decimal level dilution plate technique.
Sucrose nitrate medium consisting of sucrose (50.0g), KNO
3
(10.0g), KH
2
PO
4
(5.0g), MgSO
4
. 7H
2
O (2.5g) and 1000 mL
double distilled water used as basal medium. There were 10
different pH level ranging from 2.0 to 6.5 with a difference of
0.5 were prepared by using pocket size pH meter HANNA
Instrument Co. Mouritius by using either N/10 HCl or NaOH
before autoclaving. 100 mL of the medium was taken in 250
mL conical flask and five replicate sets were used in each
case. The solution was autoclaved at 15 psi for 15 minutes.
The inoculation was done with 3 mm discs of the fungus
culture cut with a sterilized cork borer from a margin of 10
days old colony growing in Potato Dextrose Agar (PDA)
medium. Flasks’ were then inoculated at 26ºC ± 2ºC for two
weeks. The mean dry weight of the mycelium was determined
as described by Prasad and Chaudhary (1966). The number
of spores was counted using known depth of Haemocytometer
slide (0.01 cm) using the formula:
Where,
ABSTRACT
Effect of pH on the growth and sporulation of
Fusarium oxysporum
Schlecht . f . sp.
lentis
(Vasudeva and
Srinivansan) after incubation of two weeks
in vitro
culture in sucrose nitrate medium was studied. pH level 6.0
was found optimum for the growth as well as sporulation of the fungus. Sporulation of chlamydospore was
however found best in the pH level 4.0. Further increases in the pH level show retarding effect on growth and
sporulation. Size of the spores increases with increase in the pH range.
KEY WORDS
Fusarium oxysporum
f .
sp.
lentis
Macro conidia
Micro conidia
Chlamydospores
Received on :
16.02.2011
Accepted on :
19.04.2011
*Corresponding
author
Number of spores / 100 mL = V/NX100
N = Average number of spores per square of the four corner
square of haemocytometer counted.

290
HIMANSHU BHUSHAN JARUHAR AND AJAY PRASAD
and sporulation of the fungus. On the other hand sporulation
of chlamydospores at more acidic range indicates that this
spore is characteristically different from other two spores and
more tolerable to stressed condition than the macro and micro
conidia.
ACKNOWLEDGEMENT
The
authors are happy to record the grateful cooperation of
the persons concerned of the G.L. A. College, Medininagar, in
the completion of this work.
REFERENCES
Ali, M. 2007.
Augmentation of Pulses Production. Mission2007: IIPR
Kanpur-24: pp: 16-21
Chaudhary, S. K. 1971.
Studies of the Physiology of the
Fusarium
oxysporum
f.
udum
(Butler) Snyder and Hansen (Causal Organism of
Wilt of
Cajanus cajan
(Linn.) Millsp) Ph.D. Thesis, Deptt. of Bot.
Ranchi University Ranchi, p. 297.
Groenewald, S. 2005.
Biology, Pathogenicity and Diversity of
Fusarium oxysporum
f. sp.
cubense
. M.Sc. (Agri.) Thesis. Faculty of
Natural and Agricultural Science, Universiity of Pretoria etd, Pretoria.
p. 176.
Jat, R. G. and Goyal, J. P. 1978.
Physiological Studies of
Claviceps
microcephala
Causing Ergot Diseases of Bajra.
Ind. J. Mycol. and Pl.
Pathol.
8:
21.
Kishore, R., Pandey, M., Dubey, K. and Kumar, Y. 2009.
Effect of
Temperature and pH on Growth and Sporulation of
Fusarium
oxysporum
f. sp.
lini
(Bolley) Snyder and Hensan Causing Linseed
Wilting.
Prog. Agric
.
9(1):
147-149.
Mix, A. J. 1933.
Factors Affecting the Sporulation of
Phyllosticta
solitaria
in Culture.
Phytopath.
23:
503.
Munjal, R. L. and Gautam, S. R. 1977.
Effect of vitamins on growth
and sporulation of
Septoria humuli
. Indian Phytopath.
30:
566-567.
Nair, P. N. 1957.
Factors Affecting Resistance of Flax to
Fusarium
oxysporum lini
(Belley). Dis. Abstr.
17(5):
942.
Prasad, A., Chaudhary, R. S. and Chaudhary, S. K. 1992.
Effect of
Different pH levels on Growth and Sporulation of
Fusarium
moniliforme
V.
subglutinans
Wr. and Rg., The Causal Organism of
Wilt of Maize.
Bio. J.
4(1 and 2):
75-78.
S. No. pH range Dry wt. in mg. Spores in millions /100mL medium* Size of spores in μ*
Macro conidia Micro conidia Chlamydo spores Macro conidia Micro conidia Chlamydo spores
1 2.0 37.00 0.67 2.62 0.39 26.20 7.20 4.90
2 2.5 53.00 0.78 3.63 3.51 27.70 7.30 4.90
3 3.0 73.00 1.17 4.06 3.64 28.20 8.10 6.10
4 3.5 93.00 1.55 7.42 5.20 28.90 8.90 6.30
5 4.0 124.00 1.69 9.37
4.03 29.20 9.60 7.30
6 4.5 169.00 1.95
13.68 3.71 30.70 9.80 7.50
7 5.0 198.00 2.19
19.68 3.71 31.20 10.70 7.50
8 5.5 276.00 2.62
69.14 2.73 33.30 12.30 8.20
9 6.0 476.00 5.86 154.03
2.19 34.20 12.90 8.30
10 6.5 210.00 3.69 132.42
3.51 31.10 9.20 8.50
SE± 15.24 1.50 5.78 1.74 0.05 0.18 0.24
C.D. at p= (5%) 30.97 3.14
11.75 3.54 0.11 0.36 0.48
Table 1: Effect of different pH levels of mycelia growth, spore population and size of spore change of
Fusarium oxysporum Schlecht. F.
sp.
Lentis
(Vasudeva and Srinivasan). Incubation period: 2 Weeks
*mean of five replicates
V = Volume of haemocytometer (0.256 x10
-5
) cc
Length of the spores was measured by calibrated ocular
micrometer under compound microscope (10 x 45 x of
magnification).
RESULTS AND DISCUSSION
The mean dry weight of mycelium and sporulation of three
spore forms of the fungus on different pH levels is recorded in
Table 1. The perusal of the results showed that
Fusarium
oxysporum
Schlecht. f. sp. l
entis
grew maximum in pH 6.0.
Very high acidic range of pH showed very poor growth of
mycelium. Mycelial mat accumulation increased with increase
in pH but declined after pH 6.0. Sporulation of the
macroconidia and microconidia was observed to be
maximum at pH 6.0. Least sporulation occurred in pH 2.0.
Chlamydospores produced were noted to be the maximum at
pH 4.0. Length of macroconidia and microconidia were the
maximum at pH 6.0 and thereafter it started to decline. Diameter
of chlamydospores increased with increase in pH level.
The growth and sporulation of many fungi have been studied
under the influence of various pH levels. Mix (1933) found
that pH range from 4 to 8 showed good growth for
Phyllosticta
solitaria.
Wilson (1946) observed acid soil (pH 4.2) support
growth of
Fusarium
spp. where as a pH near neutrality prevents
growth. Chaudhary (1971) and Prasad
et al
. (1992) reported
6.0 pH level as the best for the growth and sporulation of
Fusarium moniliforme
v
subglutinanse
Wr. and Rg. Munjal
and Gautam (1977) observed that maximum fungal growth
and sporulation occurred at pH 6.0 and 5.5 respectively for
Septoria humuli
. Srobar (1978) found pH 6 to be the most
suitable for the growth of all species while a highly acidic
medium was unsuitable for sporulation of all species causing
fusarioses disease in wheat. Jat and Goyal (1978) found that
growth and sporulation of
Claviceps microcephala
to be
optimum at pH 7.5 and 6.0 respectively. Nair(1957); Souramma
and Singh (2004); Groenewald (2005); Kishore
et al.
(2009)
also found pH 5.5 to 7.0 to be the best for growth and
sporulation of
Fusarium oxysporum f.
sp
. lini
( Belley). Such
reports are in agreement with present findings for this pathogen.
This indicates that unusual acidity badly hampered the growth

मंगलवार, 26 फ़रवरी 2013

Accountability and Responsibility in Journalism






Ever since its inception, Rakshak foundation has been constantly engaging in reviewing bills under consideration in the Parliament on various issues affecting the policy level initiatives in the social sector and submitting well researched opinions and recommendations on the same for the consideration of the decision makers.
We would like to continue the practice and keep bringing to the attention of the policy makers of the country, various issues and perspectives affecting the lives of the masses. We further strive to initiate policy changes by publishing our research and organising policy debates and discussions on important issues.
We invite interested volunteers to join our research team and experience being part of the team drafting well researched and robust recommendations on crucial public policy issues having the potential to shape a bright future for the country.


Accountability and Responsibility in Journalism

The state of Journalism today is similar to that described by the Irish poet Edward Eggleston as “Organized gossip”. It reports everything that people would be interested in rather than everything they should know.
Since it has become a mammoth industry with turnovers running into hundreds of crores, it is dominated by the old economic principle of demand and supply. However, basic duties such as reporting truth and informing people about both the sides of the coin are something that cannot be compromised at any cost.
Journalists have to be honest fair and courageous in gathering, reporting and interpreting information; ensuring accuracy, objectivity, balance and fairness. A Journalist should be free of any obligations, whether political or corporate.. Speaking of corporations, there is no denying that Journalism and reporting like most other professions need significant capital inputs and sound business sense to survive. But, this is a profession where the stakes are much higher because it is a profession which has the power to create opinions and to shape a nation’s present and its future. Journalists must maintain dignity in expression and be sensitive while reporting on critical issues.
They should be accountable to their audience as well as to each other. Moreover, Journalists should have a commitment to promptly correct any mistakes or expose unethical practices that they may come across.
It is important to keep Journalism independent yet honest and responsible. Attempts at self-regulation do not appear to have been very successful.
We need to start with small steps like putting draft proposals on Journalism’s best practices out in the public domain on the internet to spark discussions. These discussions could be organized by way of internet polls as well as by public events like discussion panels with eminent Journalists and known public figures. We need to research best practices in journalism in other democratic countries and create proposals which are simple to understand and yet broad enough to be effective. We will also need volunteers to engineer enough buzz on these issues in the Journalist community and the public to bring about meaningful debate at local and national level.


Promoting Responsible Citizenry

Like the common saying goes, there are three kinds of people: those who “make” things happen, those who “watch” things happen and those who “wonder” what happened. And though we would all like to believe that we fall into the first category, in terms of citizen participation most of us are very far from it. It is necessary to make a critical analysis and decide whether we are actively helping make the changes that we demand, whether we take interest and keep ourselves up to date with what goes on in our community. Do we care to critically examine voter lists for any omissions or errors and take steps to get them corrected? Do we vote? And when we vote, is it based on an objective analysis of issues and the candidates’ stand on issues and their character and capabilities? The idea that people should participate in planning, implementing and managing cities has gained wider acceptance among local governments and development agencies. It means a readiness of both the government and the citizens to accept certain responsibilities and roles. It can also mean that the value of each group’s contribution is acknowledged, appreciated and used. The honest inclusion of citizen’s representatives as “partners” in decision-making, makes for successful participation. For Citizen’s participation to be truly effective, it is necessary for the people to be involved in all stages of planning, design, implementation and evaluation of an urban program or project. The very success of a project may sometimes depend on the degree of participation of the beneficiaries.


Improving Quality of Life – Infrastructure, Traffic, Pollution and Basic Necessities

With growing population in India and the resultant strain on the resources, natural as well as man-made, along with the stiff competition to acquire them, the quality of life for the common man deteriorates with every passing day.
Citizens experience a wide disparity in the quality of, and access to, infrastructure and services. While the urban elite and middle class enjoy 24 hour electricity and water supply through individual investment in generators, private wells, storage tanks etc. The urban poor are left to cope with frequent power cuts and intermittent or non-existent water supply. Overall, the lack of high quality infrastructure, security and services hinders cities’ ability to become engines of inclusive, sustainable growth.
The Economies of scale and success stories of community based development of resources and services are well known. Individual investments for catering to the personal needs for these resources and services is intrinsically inefficient and wasteful both monetarily and on the resources of nature. The origins of municipalities and other local governing bodies lies in these very fundamentals of pooling the resources of the community through contributions (via. local taxes) to create and maintain the essential services for all. But, with explosive unplanned growth in urban population, poor public oversight and rampant corruption there is a complete breakdown of this local governance. No solution for this state of affairs will succeed without involvement of local population into the process to renovate and rebuild the existing systems. The success lies in our ability to gather enough attention from the public on this and initiate a strong dialog at the local level. We are in a better position today to reach the masses by employing the technological innovations of social networking and the internet. This effort has to be first started and perfected at the major cities where people are better connected with modern communication mediums of mobile and internet. Once perfected it can be replicated across the country for other cities.
We should invite researchers to engage in projects and develop innovative solutions to most important challenges in the areas of space constraint in cities, public transport, safe drinking water, sanitation, public safety and security, energy efficiency, waste processing, pollution and institutional reforms. We must involve the local population, they being the most important stakeholders, in all discussions on the proposed solutions and the implementation strategies.


Improving Accountability, Efficiency and Transparency of Public Offices

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Nationalism, Social Responsibility and Civil Society

Education is the process by which society deliberately transmits its accumulated knowledge, skills and values from one generation to another. The role of education in facilitating social and economic progress is well recognized. It opens up opportunities leading to both individual and group entitlements. Education, in its broadest sense of development of youth, is the most crucial input for empowering people with skills and knowledge and giving them access to productive employment in future.
Education should also prepare the children to be the rightful future citizens aware of their social responsibilities and equipped with the skills to effectively participate in furthering the common social good. Imbibing the young minds with proper ethical values, imparting skills of team work and leadership and learning to do creative things individually and in groups have to be an essential part of a holistic education. Building social skills at an early stage of education is essential so that our youth entering the colleges can handle the sometimes difficult dialogs involving the religion and the socio-economic structure. Education should also enable them as individuals later in life to rise above their differences of caste, religion or economic status and help them arrive at consensus on issues important for the growth of the nation. A comprehensive education curriculum needs to familiarize the students at the appropriate stage with the political process and the practical insight into the structure of government and its functioning. This will enable them for greater and effective participation in the political process by taking leadership role in the society. Improvements in education are not only expected to enhance efficiency but also augment the overall quality of life. The objective of national education should be to develop an army of proud and independent Indians striving for innovation, creativity and excellence in all walks of life. The education must fill the youth with a spirit of supreme confidence in themselves and in their nation with an awareness that he/she has something to offer to the country and to the world.. We invite volunteers to join out team researching on the education curriculum at the primary schooling all the way to the high schools and identify the gaps that exist at various stages. Development of such a comprehensive curriculum either from bottoms up or by way of augmenting the existing one has to be done in stages. This multi-stage approach is required so as to build consesus on need for a change in the current curriculum as well as to demonstrate the tremendous benefits of introducing it at the school level.
To start with,we have tasked our volunteers to evolve a complementary curriculum such that it can be introduced to students in a workshop setting allowing the students to benefit from its diverse content. We are also developing ways to measure the benefits of such workshops to the students in instituting the kinds of skills that the proposed revolutionary curriculum aims to bring about.


Promoting positive aspects of our culture and society

India has made tremendous strides in the last 2-3 decades in the fields of communications which include radio, television, mobile telephony and internet access. We now have our own communications satellites, a vast network of mobile services and hundreds of TV channels which reach at least 90% of our population. Perhaps, as a result of the almost explosive and seemingly uncontrolled growth in the number of TV channels over a relatively short period of time of 10-15 years, the sole motive has remained maximization of profits and earnings from advertisement revenue. In a cut-throat race for increasing the TRP which are linked to earnings from ads, the stress has been on serving to the viewers the sensational and often what is base and vulgar. A vast number of TV serials base their stories and themes on deviant or abhorrent behavior in the society or purport to depict the fanticised life-styles of a minuscule super-rich section of the society. The cinema industry is indulging in the same behavior for producing a majority of their films.
India has a rich culture. Many religions and faiths have prospered together in harmony. There have been conflicts too but good sense has always prevailed. TV can be an instrument to promote the harmony in the society by emphasizing and educating the masses with what is good and positive in each faith and what good work is being done by the followers of each faith. Numerous individuals and organizations are doing exemplary work by way of philanthropy, by educating the underprivileged, by helping the poor, sick or the destitute which must be highlighted to encourage others to devote some of their energies for the good of the society. The heroic deeds by individuals in everyday life need to be similarly broadcast to the public. There are many public servants who are doing good honest work and are putting ‘good governance’ in to practice. These individuals must be invited on TV to speak about their approach to work which will encourage their co-workers to follow similar practices and it will foster a bond between the public and the public servant.
TV is a powerful medium whose power and capability to positively impact the thinking and behavior of the masses has remained untapped and largely forgotten. TV is a visual medium which can benefit even the illiterate. We at Rakshak wish to help evolve suitable controls and policies through discussions, public debate on various fora, researching best practices elsewhere and tailoring them to the local and national needs and getting the TV channel functionaries involved in all such discussions. As a condition for permitting the use of radio-waves for transmission, the TV channels can be required to devote a certain proportion of their total telecast for programs which provide the citizens with facts, information, knowledge of local issues, opinions of thinkers, experts and respected members of the society. Citizens need to be informed and educated about their rights, they need to be informed the phone numbers of various services, procedures to get a problem addressed with clear accountability of public servants, to be informed of clear steps and procedure to submit an RTI application or a complaint in a Consumer Forum and so on. TV needs to be utilized on a much larger scale for spread of education amongst the underprivileged children and youth and for adult literacy through regional language programs. Various Departments and Ministries have large funds budgeted for public information which can be put to good use for promoting the aforesaid activities/programs on TV.