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Papers by sriram krishna

Research journal of biotechnology

Capsicum annuum L. is a commercial crop which belongs to the Solanaceae family and it is widely g... more Capsicum annuum L. is a commercial crop which belongs to the Solanaceae family and it is widely grown in tropical and sub tropical regions of the world. Capsicum seeds consist of different types of soluble proteins. In the present study we analyzed the biochemical relationship among the sixteen genotypes of Capsicum annum L. Seed protein profiling was generated in sixteen genotypes of chilli seeds through SDS- PAGE. The analysis showed 92 bands and considerable variation in banding pattern. Dendrogram was constructed based on protein profiling score using NTSYS software. Total sixteen genotypes were grouped into four clusters. Based on this diversity study, CA 1, 2 and 5 are highly diversified with CA 12, 13, 15 and 16 genotypes. Based on this study, highly diversified genotypes could be utilised for chilli breeding programme.

Understanding the concept of symbiosis in a more localized natural selective way and optimizing f... more Understanding the concept of symbiosis in a more localized natural selective way and optimizing for the yielding advantages of confined geography is the prime objective of the study. Precisely the aim is to isolate and identify crop specific Rhizobium strains for Glycine max using physical, biochemical and in silico techniques from Bhadrachalam forest lands. Randomly collected soil samples from 45 different locations across Bhadrachalam forest were sown with soybean in triplets. The basic parameters like Nitrogen, Phosphorous, Potassium (NPK) and levels of micronutrients for all the soil samples were identified to be similar. Out of 45 samples in triplets, top five growth supporting soils were taken for further investigation. Organisms from the root nodules of these five plants were screened and pure cultures were maintained. Log phase cultures in broth form were inoculated on the seeds sown in sterile soils with respective controls. Tremendous improvement in the growth parameters were observed in results when compared with controls. The polyphasic analysis discovered that the contributing organisms were Bradyrhizobium japonicum, Bradyrhizobium paxllaeri, Bradyrhizobium canariense, Sinorhizobium xinjiangense, Bradyrhizobium betae sp. Pure forms of these Rhizobial species have shown elevated rate of plant growth in in vitro fallowed by field experiments in low vegetative agriculture soils of the same geography. Out of these five species the Bradyrhizobium japonicum, which was the best plant growth supporting for Glycine max has been studies further to explore the Nif genes responsible for plant growth and Nitrogen fixation. The in-silico analysis of Nif A protein revealed the underlying precursors of indole acetic acid (IAA) production and nitrogenase activity. This novel method of soil selection may be adopted for easy identification of Rhizobial species, specific for not only for Glycine max but also for various other legume crops from respective geographies.

Zea mays is one of the most important stable foods in Asian and African countries and is the seco... more Zea mays is one of the most important stable foods in Asian and African countries and is the second-largest cultivated and highest-yielding crop in India. Lepidopteron stem borer Chilo partellus is a dangerous insect pest in maize. The stem borer makes holes on the stem and leaves and enters inside the stem for feeding. The plant was therefore investigated for its bioactive components. The present study was carried out to identify the volatile compounds present in the n-hexane extract of Zea mays by GC-MS analysis. Total 30 compounds were identified in both infected and uninfected samples. Among the 30 compounds butylated hydroxytoluene, n-hexadecanoic acid and 9,12,15-octadecatrienoic acid, (Z,Z,Z)-were identified as three common major components. Differences in their concentrations reveal their role in plant-insect interactions.

Development of QPM (Quality Protein Maize) with high lysine and tryptophan is of foremost importa... more Development of QPM (Quality Protein Maize) with
high lysine and tryptophan is of foremost importance in
maize breeding programme. Marker assisted selection
in back cross breeding is the easiest way of developing
QPM hybrids in less time. The present investigation
was to attempt for conversion of elite maize inbred line
BML-7 into QPM line. CML-181 was identified as a
donor which showed good polymorphism with BML-7
for opaque-2 gene specific marker umc1066. Non-
QPM inbred line BML-7 was crossed with QPM donor
CML-181 and produced F1 followed by BC1F1 and
BC2F1 population was developed. Foreground
selection was carried out with umc1066 in F1 and
selected plants were used for BC1F1 and BC2F1
populations. Two hundred plants were screened in both
BC1F1 and BC2F1 population with umc1066 for
foreground selection.

Anthracnose is a well-known disease caused by Colletotrichum capsici/truncatum resulting in both ... more Anthracnose is a well-known disease caused by
Colletotrichum capsici/truncatum resulting in both
qualitative and quantitative yield loss of a commercial
vegetable crop chilli. Variability among the C.
truncatum species with respect to geographical
distribution remained as a major constraint to chilli
production. Hence present study was aimed at
identifying the genetic variability existing among the
species within Andhra Pradesh region. Eight different
isolates were characterized and confirmed as C.
capsici with species specific marker. Variations among
the isolates exist in their cultural and morphological
features including aerial fluffy cotton to submerged
felty type colonies at a growth rate of 3.8-9.8 mm per
day while conidial size varied from 18.1-22.36 μm in
length to 2.8-4.0 μm in width.

Objectives: To isolate and identify the crop specific Rhizobium strains for Glycine max from Bhad... more Objectives: To isolate and identify the crop specific Rhizobium strains for Glycine max from Bhadrachalam forest lands
by an indigenous novel strategy to reduce the input cost in exploration of compatible strains for soybean avoiding serious
constrain of bio-fertilizers i.e., shelf life. Materials and Methods: Soil samples were collected randomly from 40 different
locations of Bhadrachalam forest and sown with ground nut seeds in triplets. Five out of 40 samples which supported the
best plant growth were taken for further investigations. The NPK and micronutrient levels of all the soil samples were found
to be comparatively similar. This may be because of the fact that all samples have been taken from same geographic region.
Rhizobial strains from the root nodules of these five samples were isolated and maintained in pure cultures. Broths of each
pure culture were inoculated on the seeds sown in sterile soil and controls were maintained. Findings: The results showed
that the inoculated Rhizobia tremendously improved the plant growth when compared with control. Further phylogenetic
analysis revealed that the contributing organisms were Rhizobium leguminosarum, Rhizobium trifolii, Rhizobium meliloti,
Rhizobium phaseoli and Bradyrhizobiumjaponicum. These Rhizobial species in the pure form exhibited high rate of plant
growth at lab conditions followed by improved growth in low vegetative agriculture soils of the same geography. The 16S
rRNA gene sequences revealed the fact that soil sample 3 contain abundant Rhizobium leguminosarum sp., with 99%
similarity. The sample 1, 2, 4 and 5 contain abundant levels of Rhizobium trifolii, Rhizobium meliloti, Rhizobium phaseoli
and Bradyrhizobiumjaponicum respectively. Application: Therefore this method could be applied for the preliminary
screening of compatible, species specific strains for any leguminous plants making the process easy and less expensive

Transgenic Bt Cottons expressing Cry protein are proved to be toxic to bollworms played significa... more Transgenic Bt Cottons expressing Cry protein are proved to be toxic to bollworms played significant role
in reducing crop losses. Besides Cry protein expression level, spatial and temporal expression of Cry
protein plays a very crucial role in attaining hosts resistance. In the present investigation, we focused on
the effect of four cotton diseases on Cry protein expression in JK Durga Bt cotton hybrids at 60 and 120
DAS (with Grey mildew), at 120 DAS (with Tobacco Streak Virus) and at 150 DAS (with Bacterial Leaf
Blight). Experiment results revealed that there is no significant difference in the expression of cry protein
between healthy Bt cotton hybrids and diseased hybrids. Thus, we conclude that there is no effect of
disease incidence on the Cry protein expression which in turn conveys that the expression of Cry1Ac
protein, responsible for resistance against insects is not influenced by other diseases on the plant.

Soil is major reservoir for microbes and harbors a vast microbial diversity. Soil microbiota play... more Soil is major reservoir for microbes and harbors
a vast microbial diversity. Soil microbiota plays a pivotal
role in biogeochemical cycles, bioremediation, and in
health and disease states of humans, animals, and plants. It
is imperative to understand the microbial signatures which
are specific in such an ecosystem to unravel their potential
role and impact on environment. During the recent years,
exploration of soil microbial communities has been geared
up with the advent of advanced sequencing technologies.
Introduction of custom-made protocols and optimized
procedures have enhanced the accuracy levels along with
cost-effectiveness of DNA extraction. Standardization of
DNA extraction method from soil microbiota has its own
limitations due to different nature of soils and the complexity
of ecosystems. Though a few standardized protocols
are in usage, huge variations and complexities among
the microbial communities frequently suggest the optimization,
based on various known and unknown factors.
Therefore, a set of four standardized DNA isolation protocols
was comparatively analyzed with respect to our
custom-made protocol owing to the scientific fact that the
same protocol does not hold good for all soil samples.
Furthermore, the developed protocol has been successfully
applied for the identification of efficient plant-specific
Rhizobial stains for five legume plants from the soils of
various locations under same geographical region. Out of
40 Badrachalam forest soils, five samples, KPFS36, CHFS17, TPFS33, GVFS06, and GPFS40, one for each of
Arachis hypogaea, Vigna radiata, Vigna mungo, Glycine
max, and Cicer arietinum plants, were selected, respectively,
for the soil DNA extraction. A considerable
improvement in the DNA yield was identified using the
modified protocol with a yield of 21.08 lg/g providing
abundant DNA fragments for further investigation on
Rhizobial species

Soil has been one of the major habitats for microbial communities in the ecosystem. It is a well ... more Soil has been one of the major habitats for microbial communities in the ecosystem. It is a
well established scientific fact that Microorganisms are ubiquitous in nature, and not more than one
percentage of the microbial population has been explored. The quest of microbial exploration in the
name of biodiversity is being carried, as a result of which more and more novel microbial communities
are getting added to the literature. One such attempt has been made with an indigenous strategy to
reduce the input cost in exploration of compatible strains for chickpea avoiding serious constrain of
biofertilizers i.e, shelf life in the name of acclimatization. Forest lands of Bhadrachalam receive heavy
rain fall and are rich in microbial biomass. Soil samples are collected randomly from 40 different
locations of Bhadrachalam forest and sown with chickpea seeds in triplets. Five out of 40 samples
which supported the best plant growth were taken for further investigations. The NPK and micronutrient
levels of all the soil samples were found to be comparatively similar. This may be because of the fact
that all samples have been taken from same geographic region. Rhizobial strains from the root nodules
of these five samples were isolated and maintained in pure cultures. Broths of each pure culture were
inoculated on the seeds sown in sterile soil and controls were maintained. The results showed that the
inoculated Rhizobia tremendously improved the plant growth when compared with control. Further
phylogenetic analysis revealed that the contributing organisms are Mesorhizobium Ciceri, Rhizobium
meliloti, Rhizobium fredii, Bradyrhizobium japonicum, Mesorhizobium loti sp. These Rhizobial species in the
pure form exhibited high rate of plant growth at lab conditions followed by improved growth in low
vegetative agriculture soils of the same geography. This infers that a simple strategic pot experiment
could be applied for the preliminary screening of compatible, species specific strains for any
leguminous plants making the process easy and less expensive.

Soil has been one of the major habitats for microbial communities in the ecosystem. It is a known... more Soil has been one of the major habitats for microbial communities in the ecosystem. It is a known fact that
not more than one percentage of the microbial population has been explored. The quest of microbial
exploration in the name of biodiversity is being carried, as a result of which more and more novel
microbial communities are getting added to the literature. The aim of the study is to isolate and identify
the crop specific Rhizobial strains for Glycine max from Bhadrachalam forest lands by an indigenous
novel strategy to reduce the input cost in exploration of compatible strains for soybean avoiding serious
constrain of biofertilizers i.e, shelf life. The results showed that the inoculated Rhizobia tremendously
improved the plant growth when compared with control. Further phylogenetic analysis revealed that the
contributing organisms are Bradyrhizobium japonicum, Bradyrhizobium elkanii, Sinorhizobium fredii,
Bradyrhizobium yuanmingense, and Bradyrhizobium liaoningense sp. These Rhizobial species in the
pure form exhibited high rate of plant growth at lab conditions followed by improved growth in low
vegetative agriculture soils of the same geography. Therefore this method could be applied for the
preliminary screening of compatible, species specific strains for any leguminous plants making the
process easy and less expensive.
KEYWORDS: Rhizobial strains; NPK; Micronutrient Levels; Plant Growth Promoting Rhizobacteria; Glycine max
Received on : 14-11-2016
Revised and Accepted on : 22-03-2017
DOI: http://dx.doi.org/10.22376/ijpbs.2017.8.2.b401-408

Introduction: Diseases and its causative pathogens are the remarkable challenges faced by a plant... more Introduction: Diseases and its causative pathogens are the remarkable challenges faced by a plant for its survival, eventually to cause severe food security problems. Host resistance is an eco-friendly approach which requires a depth understanding on host–pathogen interactions. During these interactions, a cascade of defense responsive antioxidants was induced by a pathogen with respect to the type of cultivar while causing a disease. These array of enzymes can be biochemically detected and aid as markers to identify the ability of the host to restrict the pathogen. This study was conducted to detect the Colletotrichum truncatum elicited defense responsive antioxidants among the seedlings of G-4, LCA-353, BSS-355, and S-2 chili cultivars. Materials and Methods: Chilli seedlings of 25 days old were spray inoculated with pathogen and after 7 days of infection their antioxidant potential was analyzed by estimating few enzymes, viz., phenylalanine ammonia lyase, polyphenol oxidase, superoxide dismutase, catalase, 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, reducing power, and total phenol content. Results: Biochemical estimations revealed that G-4 cultivar to be a resistant variety showing increased production of defense induced enzymes in all parameters while in contrast BSS-355 remained as susceptible variety. Conclusion: Anthracnose induced antioxidative enzymes showed a significant correlation between the enzymes, unveiling G-4as resistant and BSS-355 to be the susceptible chili cultivar with the highest and lowest enzyme activities. Identified resistant cultivar can be used in anthracnose resistant breeding programs and also these enzymes can be employed as biochemical markers to screen the chili genotypes against anthracnose disease.

Abstract Improvement of quality protein maize (QPM) along with high content of lysine and tryptop... more Abstract Improvement of quality protein maize (QPM)
along with high content of lysine and tryptophan had
foremost importance in maize breeding program. The
efficient and easiest way of developing QPM hybrids was
by backcross breeding in marker aided selection. Hence,
the present investigation aimed at conversion of elite maize
inbred line BML-7 into QPM line. CML-186 was identified
to be a donor variety as it revealed high-quality polymorphism
with BML-7 for opaque-2 gene specific marker
umc1066. Non-QPM inbred line BML-7 was crossed with
QPM donor CML-186 and produced F1 followed by the
development of BC1F1 and BC2F1 population. Foreground
selection was carried out with umc1066 in F1, and selected
plants were used for BC1F1 and BC2F1 populations. Two
hundred plants were screened in both BC1F1 and BC2F1
population with umc1066 for foreground selection amino
acid modifiers. Foreground selected plants for both opaque-
2 and amino acid modifiers were screened for background
selection for BML-7 genome. Recurrent parent
genome (RPG) was calculated for BC2F1 population plants.
Two plants have shown with RPG 90–93% in two generation
with back cross population. Two BC2F2 populations
resulted from marker recognized BC2F1 individuals subjected
toward foreground selection followed by tryptophan
estimation. The tryptophan and lysine concentration was
improved in all the plants. BC2F2 lines developed from
hard endosperm kernels were selfed for BC2F2 lines and finest line was selected to illustrate the QPM version of
BML-7, with 0.97% of tryptophan and 4.04% of lysine
concentration in protein. Therefore, the QPM version of
BML-7 line can be used for the development of single
cross hybrid QPM maize version.

Improvement of QPM(Quality ProteinMaize) along with high content of lysine and tryptophan had for... more Improvement of QPM(Quality ProteinMaize) along with high content of lysine and tryptophan had foremost importance
in maize breeding programme. The efficient and easiest way of developing QPM hybrids was of backcross
breeding in marker aided selection. Hence the present investigation was aimed with an endeavour to
convert elite maize inbred line BML-6 into QPMline. CML-181 was identified to be a donor variety as it revealed
high-quality polymorphismwith BML-6 for opaque-2 gene specificmarker umc1066. Non-QPMinbred line BML-
6 was crossed with QPM donor CML-181 and produced F1 followed by BC1F1 and BC2F1 population was developed.
Foreground selection was carried out with umc1066 in F1, and selected plants were used for BC1F1 and
BC2F1 populations. Two hundred plants were screened in both BC1F1 and BC2F1 population with umc1066 for
foreground selection. The selected plants were screened for foreground selection with amino acid modifiers.
Foreground selected plants for both opaque-2 and amino acid modifiers were screened for background selection
for BML-6 genome. Recurrent parent genome (RPG) was determined for BC2F1 population plants. Three plants
have shown with RPG 90–93% in two generation back cross population. Three selected BC2F2 populations were
screened for foreground and back ground selection followed by agronomical and biochemical evaluation. The
QPM converted version of BML-6 contains 0.97% of tryptophan and 4.02% of lysine concentration in a protein.
Agronomical and biochemical screened BC2F2 plants were selfed for BC2F3. QPM version of BML-6 line can be
used for the development QPM version of maize single cross hybrids

Pheromone-binding proteins (PBPs) play a significant role in olfaction and mating. The present wo... more Pheromone-binding proteins (PBPs) play a significant role in olfaction and mating. The present work was designed to isolate, extract, and purify the pheromone-binding proteins from the antennae of male Chilo partellus (Swinhoe, 1885) (Lepidoptera: Crambidae). The pheromone-binding proteins extracted from the male antennae were found to be 770 μg in 100 mg of sample. Pheromone-binding protein molecular weight was determined as 17 kDa by SDS-PAGE analysis. Identified proteins were purified through gel extraction with a recovery percentage of proteins up to 95%. Purified protein samples are analyzed on native PAGE gels. Relative mobility of proteins was determined as 0.574 nm in the densitometry analysis. These identified pheromone-binding proteins can be used for identification of novel pheromone compounds in in vitro studies. This study can be helpful in designing integrated pest management programs to control the maize stem borer by mass trapping of male moths.

The Life cycle of maize stem borer, Chilo partellus (Swinhoe) was studied in in vitro conditions.... more The Life cycle of maize stem borer, Chilo partellus (Swinhoe) was studied in in vitro conditions. Development of stem borer undergoes following stages like egg, larvae, pupa and moth. The egg incubation period ranged from 3 to 6 days, larval stage was observed in five instars. The mean value of I, II, III, IV and V instars showed 3.8 ± 0.16, 5.2 ± 0.02, 6.1 ± 0.06, 7.35 ± 1.5, and 10.12 ± 0.29 days, respectively and complete larvae period ranged from 42 to 49 days. Pupae stage was observed in 8-9 days. The pre-mating and mating period was found at 9.10 ± 1.20 and 5.14 ± 1.08 h while egg laying period in 4.1 ± 1.32 days respectively. Fecundity rate of stem borer is from 262 to 657 eggs. The life span of adult male (3-7) and female (3-8) days was observed with a mean of 6.30 ± 0.85 and 5.10 ± 0.69 days respectively. Life cycle of stem borer gets completed in 47 to 51 days. Development of quality insects in required quantities at different developmental stages and their timely supply plays an inevitable role particularly for insect-breeding resistant programs. Hence to meet these challenges we had tried to standardize an artificial diet with cost effective to rear Chilo partellus under in vitro conditions.

Altering climatic conditions and water stress drastically affects the chilli crop yield. In this ... more Altering climatic conditions and water stress drastically affects the chilli crop yield. In this scenario we adapted a strategic approach for screening of elite chilli genotypes, by exploring role of seed antioxidants in stress tolerance during vegetative phase. A total of 20 chilli genotypes' seed antioxidant potential and its effect on water stress tolerance were studied at three water regimes, namely, control (100% Field Capacity), moderate (80% Field Capacity), and severe (60% Field Capacity) stress conditions. Drought tolerance traits relative water content, chlorophyll content, and activities of superoxide dismutase and catalase enzymes were measured. A strong correlation was observed between seed antioxidants and water stress tolerant traits in seedlings. Genotypes KCa-5, KCa-6, and KCa-10 showed low quantity of H 2 O 2 and Malondialdehyde in seeds and maintained high membrane integrity and chlorophyll content in seedlings. High content of proline in KCa-5, KCa-7, and KCa-10 seeds retained high relative water content at seedling stage under severe water stress. Present work reveals genotypic differences of hot pepper to different water regimes. Based on Principal Component Analysis (PCA) of seed antioxidant variables and drought tolerance indices twenty genotypes segregated into three clusters, namely, drought tolerant and susceptible and moderately tolerant.

In the agricultural ecosystems, environmental stresses impede plants from expressing full genetic... more In the agricultural ecosystems, environmental stresses impede plants from expressing full genetic
potential. Water stress is one of the major constraints of agriculture production in the world. Everchanging
environmental conditions and lowered ground water levels remained as a significant cause
for increased water stress conditions. As chilli is highly prone to water stress owing to their shallow
roots, present investigation was carried out to identify drought tolerant genotypes in hot pepper. To
distinguish different physiological and biochemical characteristics, twenty six hot pepper genotypes
were subjected to mild (80% Field Capacity), moderate (60% Field Capacity) and severe water
stress (40% Field Capacity) for one week in the green house. From the present investigation, a
significant accumulation of proline and malondialdehyde levels and decrease in the chlorophyll
content and relative water content was observed among 26 genotypes. A significant negative
correlation was observed between relative water content and Ion Leakage. Furthermore, genotypes
showed different responses to drought stress. Principal Component Analysis revealed differential
interrelationships among different traits under control and stress conditions. From present
investigation five genotypes viz., SHP4884-1-1, LCA353-1-1, BSS355-1-1, CA960-1-1 and LCA334-1-
1 were considered to be drought tolerant while four genotypes viz., G4-1-1, S2-1-1, Preethi-1-1 and
NCH5-1-1 were considered as drought susceptible. Identified drought tolerant genotypes may be
used as parents in the breeding programme.

Improvement of QPM (Quality Protein Maize) along with high content of lysine and tryptophan had f... more Improvement of QPM (Quality Protein Maize) along with high content of lysine and tryptophan had foremost importance in maize breeding programme. The efficient and easiest way of developing QPM hybrids was of back-cross breeding in marker aided selection. Hence the present investigation was aimed with an endeavour to convert elite maize inbred line BML-6 into QPM line. CML-181 was identified to be a donor variety as it revealed high-quality polymorphism with BML-6 for opaque-2 gene specific marker umc1066. Non-QPM inbred line BML-6 was crossed with QPM donor CML-181 and produced F 1 followed by BC 1 F 1 and BC 2 F 1 population was developed. Foreground selection was carried out with umc1066 in F 1, and selected plants were used for BC 1 F 1 and BC 2 F 1 populations. Two hundred plants were screened in both BC 1 F 1 and BC 2 F 1 population with umc1066 for foreground selection. The selected plants were screened for foreground selection with amino acid modifiers. Foreground selected plants for both opaque-2 and amino acid modifiers were screened for background selection for BML-6 genome. Recurrent parent genome (RPG) was determined for BC 2 F 1 population plants. Three plants have shown with RPG 90–93% in two generation back cross population. Three selected BC 2 F 2 populations were screened for foreground and back ground selection followed by agronomical and biochemical evaluation. The QPM converted version of BML-6 contains 0.97% of tryptophan and 4.02% of lysine concentration in a protein. Agronomical and biochemical screened BC 2 F 2 plants were selfed for BC 2 F 3. QPM version of BML-6 line can be used for the development QPM version of maize single cross hybrids.

Biological control agents with ecofriendly approach now a day's remained as a requisite in crop p... more Biological control agents with ecofriendly approach now a day's remained as a requisite in crop protection strategy against indiscriminate usage of chemicals. Contemporarily integration of technology made fungal agents potent with broad spectrum control. Hence present work aims at determining the antimycotic ability of Trichodermae species as biocontrol agent in controlled conditions against phyto-pathogens like fusarium and Colletotrichum species. Results revealed that Trichodermae viridae showed maximum inhibition on radial growth of fusarium oxysporiumf.s.p.capsici (76.74±0.4) in dual culture while its volatile metabolites on growth of C.gleosporides (53.3±0.3) and nonvolatile metabolites on C.capsici (70.94±0.6). While Trichodermae harzianum exhibited its maximum potentiality in arresting radial growth of C.capsici at 87.6±0.9 percent in dual culture while 58.6±0.2 reduction by volatile metabolites and over growth at 5% filtrate application by nonvolatile metabolites. From the results it has been illustrated that both Trichodermae species may serve as biological agents and in combination work effectively to control plant diseases with respect to their mode of infection and host pathosystem promoting harmful chemical free agricultural practices.

Research journal of biotechnology