45 research outputs found
A New Proposed PDF for the Sub-Optimum Receiver Architecture
The detection performance of communication systems in general is limited by the presence of undesirable energy in the received signal. And this undesirable energy at communication receiver is modeled as the sum of gaussian noise and impulsive interference for which closed form probability density function generally does not exist. Due to this implementation of optimum receivers becomes very difficult. In this paper an alternate PDF is proposed written in closed form which provides a much simple architecture
Effect of waterlogging tolerance in wheat (Tritium aestivum L.) at ear emergence stage on growth, biochemical and yield parameters in sodic soil
Globally more than one-third of the irrigated area is under waterlogging which limits our wheat production and out of which northern Indo-Gangetic plains of India alone had 2.5 million ha affected by irregular waterlogging. So, to meet out the food demand of ever-growing population we have to find some alternates to harness the potential of the waterlogged area. With this point of view this investigation was conducted to study the changes in growth and biochemical behavior of wheat due to waterlogging at ear emergence stage in sodic soil and also to assess the traits conferring higher yield at experimental site of department of crop physiology, Narendra Deva University of Agriculture & Technology, Kumarganj, Faizabad (U.P.), India. The results showed that the genotypic variability exists for waterlogging tolerance in wheat varieties evaluated under investigation. HD-2009 which is susceptible to waterlogging gave poor performance in terms of growth parameters, biochemical behavior and traits conferring higher yield under waterlogging conditions at ear head emergence stage in sodic soil as compared to HD-2851, KRL-3-4 and KRL-99 wheat varieties. KRL-99 (1.80g yield plant-1) gave best results followed KRL-3-4 (1.37g yield plant-1) by under waterlogged conditions at ear head emergence stage in sodic soil
Increase in wheat production through management of abiotic stresses : A review
About 9% of area on earth is under crops out of which 91% is under various stresses. On an average, about 50% yield losses are due to abiotic stresses mostly due to high temperature (20%), low temperature (7%), salinity (10%), drought (9%) and other abiotic stresses (4%). As there is no scope for increasing area under agriculture, the increased productivity from these stressed land is a must to meet the ever increasing demand. Further, the severity of abiotic stresses is likely to increase due to changing climate leading to adverse effect on crops. Therefore, abiotic stresses like drought, salinity, sodicity, acidity, water logging, heat, nutrient toxicities/ deficiencies etc need to be effectively addressed through adoption of management practices like tillage and planting options, residue management, sowing time, stress tolerant cultivars, irrigation scheduling and integrated nutrient management to conserve natural resources, mitigating their adverse effect and sustainable wheat production
Host Plant Induced Variation in Gut Bacteria of Helicoverpa armigera
Helicoverpa are important polyphagous agricultural insect pests and they have a worldwide distribution. In this study, we report the bacterial community structure in the midgut of fifth instar larvae of Helicoverpa armigera, a species prevalent in the India, China, South Asia, South East Asia, Southern & Eastern Africa and Australia. Using culturable techniques, we isolated and identified members of Bacillus firmus, Bacillus niabense, Paenibacillus jamilae, Cellulomonas variformis, Acinetobacter schindleri, Micrococcus yunnanesis, Enterobacter sp., and Enterococcus cassiliflavus in insect samples collected from host plants grown in different parts of India. Besides these the presence of Sphingomonas, Ralstonia, Delftia, Paracoccus and Bacteriodetes was determined by culture independent molecular analysis. We found that Enterobacter and Enterococcus were universally present in all our Helicoverpa samples collected from different crops and in different parts of India. The bacterial diversity varied greatly among insects that were from different host plants than those from the same host plant of different locations. This result suggested that the type of host plant greatly influences the midgut bacterial diversity of H. armigera, more than the location of the host plant. On further analyzing the leaf from which the larva was collected, it was found that the H. armigera midgut bacterial community was similar to that of the leaf phyllosphere. This finding indicates that the bacterial flora of the larval midgut is influenced by the leaf surface bacterial community of the crop on which it feeds. Additionally, we found that laboratory made media or the artificial diet is a poor bacterial source for these insects compared to a natural diet of crop plant
Assessment of variation in isoproturon in susceptible and resistant biotypes of <i style="">Phalaris minor</i> Retz. by RAPD analysis
534-537The extensive use of isoproturon for the control of weeds in wheat fields for the past 20 years has lead to the formation of isoproturon resistant biotypes of Phalaris minor. This problem was first identified in Haryana and later in Panjab and some parts of Uttar Pradesh. PCR based RAPD technique, which can detect variability at DNA level was used to assess the variability among the two isoproturon susceptible and two resistant biotypes of Phalaris minor. Nine oligonucleotides (10 base) were screened for their ability to produce polymorphic bands. Three primers did not amplify DNA of one or the other biotypes. Three more did not show any polymorphism amongst the biotypes. The rest three indicated 20% polymorphism level. The size of amplified DNA segments ranged from 105 to 1020 base pair (bp). The mean dissimilarity value of these biotypes was 0.19. Highest dissimilarity (0.21) could be observed between the two resistant biotypes. Cluster analysis of the RAPDs generated separated one of the resistant biotypes from rest of the populations. Primer 20 A0 showed maximum polymorphic value of 1.0 between the susceptible biotype from Karnal and the resistant biotype from Kalwehri. This suggests that the technique could be utilized in the assessment of genetic diversity of the populations existing in other states and developing markers for the resistant trait
Evaluation of genetic diversity using random amplified polymorphic DNA (RAPD) markers in <i>Melia dubia</i> Cav.
76-83Random amplified polymorphic DNA (RAPD) molecular markers were used to evaluate the genetic diversity in populations of Melia dubia Cav. syn. M. composita Willd. (Family: Meliaceae) (Burma dek) from different agroclimatic regions of India. Of the 38 decamer primers used, 13 yielded polymorphic banding patterns. In total, 105 different bands were reproducibly obtained, of which 69 (65.7%) were polymorphic. The polymorphisms were scored and used in band-sharing analysis to identify genetic relationships. Cluster analysis based on Jaccard’s similarity coefficient using UPGMA grouped all the 24 populations into two major groups. Similarity indices ranged from 0.80 to 0.91, indicating that Burma dek germplasm within India constitutes considerably narrow genetic base
Amylase induction during seed germination <span style="mso-bidi-font-weight:bold">in<b> </b>isoproturon susceptible and resistant biotypes of <i>Phalaris minor </i>Retz. </span>
373-375Isoproturon resistant biotype of P.minor
germinates early, shows higher germination percentage and faster rate of
growth as compared to the susceptible biotype. Higher amylase activity is observed
in the initial hours of imbibition in the resistant biotype. In the susceptible
biotype it is activated at a much later stage
Rapid protocol for callus induction and differentiation of roots and shoots in Dioscorea alata—a medicinal plant
The present study was carried out to investigate the effect of different concentrations of growth regulators on in vitro
differentiation of Dioscorea through nodal explants which provide a fast, reliable and alternate method of multiplication
and facilitate ex situ conservation of this valuable plant species. Nodal explants excised from in vivo grown plants were
cultured on Murashige and Skoog (MS) medium supplemented with different combinations of plant growth substances.
The maximum (100 per cent) callus induction as well as growth was obtained on NAA (2.5 mg/l). The induced callus was
transferred onto the nutrient media supplemented with different combinations of growth regulators for the differentiation
of roots and shoots. Roots were developed on MS medium + NAA (2.0 mg/l) + IBA (0.5 mg/l), shoots on MS + BAP (2.0
mg/l) + NAA (0.5 mg/l) and roots-shoots on MS + NAA (2.5 mg/l) + 2, 4-D (2.0 mg/l) from the callus
<span style="font-size:13.0pt;mso-bidi-font-family:"Times New Roman"; mso-bidi-font-weight:bold" lang="EN-GB">Molecular assessment of genetic stability using ISSR and RAPD markers in <i style="mso-bidi-font-style:normal">in vitro</i> multiplied copies of commercial banana cv. Robusta </span>
420-424<span style="font-size:9.0pt;mso-bidi-font-family:
" times="" new="" roman""="" lang="EN-GB">The present study was carried out to monitor somaclonal
variations of banana cv. Robusta during micropropagation using random amplified
polymorphic DNA (RAPD) and inter simple sequence repeats (ISSR) markers. Shoot
tips were used as explants and regenerated on MS+BAP 4.0 mg/L medium. The
regenerated shoots were cultured on MS medium fortified with 4.0 mg/L BAP+0.25 mg/L
NAA+30 mg/L AdSO4 for multiplication. Rooting was obtained on ½ MS
medium supplemented with 2.0 mg/L NAA. Rooted shootlets were separated
individually and hardened in greenhouse. The hardened plants of banana were
screened for genetic stability using 46
(26 RAPD and 20 ISSR) primers. The number of scorable bands for each RAPD
primer varied from 1 to 9. Twenty-six RAPD primers produced 108 distinct and
scorable bands, with an average of 4.15 bands per primer and the amplification
products range was from 100-1150 bps. No polymorphism was detected during the
RAPD analysis of in vitro raised
clones. Twenty ISSR primers produced 81 distinct and scorable bands in the
range of 100-1000 bps and the number of scorable bands for each primer varied
from 2 to 8 with an average of 4.05 bands per primer. A homogenous
amplification profile was observed for all the micropropagated plants when
compared to mother plant in both types of markers used. The results corroborate
the fact that in vitro multiplication is the safest
mode for production of true to type plants.
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