Isolation of Plant Growth Promoting Bacteria from the Rhizosphere of Different Plants and Assessment of Their Plant Growth Promotion Potential Isolation of Bacteria and their Assessment for Plant Growth Promotion Potential

Plant are benefitted in different aspects by symbiotic bacteria. Environmental conditions, Plant conditions and type of pathogens determine these important services for plants Objective: The research was conducted to assess the plant growth enhancing effects of wheat and cabbage rhizobacteria on the growth of wheat plantMethods: For this purpose, total 49 bacteria were isolated and characterized from the rhizosphere of wheat and cabbage plants. The isolates were assessed for plant growth promoting properties such as: indole acetic acid production, phosphate solubilization, antibacterial activity and heavy metal resistance. Indole acetic acid was found to be produced by 7 isolates and phosphate solubilization was shown by 20 isolates. Antibacterial activity was determined against four clinical isolates like Staphylococcus aureus, Klebsiella sp, Escherichia coli and Pseudomonas aeruginosaResults: Antibacterial activity against Staphylococcus aureus was shown by 38 isolates, 12 isolates showed antibacterial activity against Escherichia coli and Klebsiella sp, whereas no isolate was found to bepositive against Pseudomonas aeruginosa. Another plant growth enhancing trait (heavy metal resistance) was shown by 28 rhizobacteria. In order to evaluate the capability of isolates to enhance the plant growth, bio-inoculation assay was performed using wheat seedsConclusions: Rhizobacterial inoculation increased the number of roots, shoots, leaves and roots and shoot length of wheat plantlets as compared to un-inoculated control.  

Estimation of Biodiversity and Physio-Genetic Parameters for Drought Tolerance in Maize Zea Mays L.

Maize genotypes including 64 in number were evaluated at early stage in greenhouse with the soil having 40-100% moisture levels for different seedling parameters on various genetic analysis revealed that the highest estimates of heritability were found for root fresh weight, root volume and shoot fresh weight, at 40% soil moisture providing the evidence that these plant characters are under the control of additive genetic effects. The results showed that selection should evolve the genetic material with improved characteristics within short time. The single linkage cluster analysis and principle component analysis identified the variation among these parameters and in genotypes under the different moisture levels. Genotypes 21 in number with moderately tolerant and drought susceptible backgrounds were further evaluated by using Inter simple sequence repeats markers to ascertain their biodiversity. So 14 number of parents with determined diversity were finally selected and were crossed in line x tester fashion and their F1 along with their related parents were grown using randomized complete block design with 3 replications under normal and 50% of normal irrigation field conditions. All the cultural and other practices were kept uniform to both plantings except irrigation. Various agronomic and physiological parameters were recorded and analyzed for analysis of variance, genotypic and phenotypic correlation, principle component analysis, cluster analysis, general combining ability analysis and specific combining ability analysis for both conditions. Highest range of broad sense heritability with higher genetic advance regarding different plant characteristics depicted that these plant characters were controlled by additive genetic effects. So, it indicates that a fast genetic improvement is found in the experimental material. Clusters with superior genotypes showed the genetic potential of accession to transfer the desirable genes to improve yield in maize. The best combiners for both normal and 50% of normal irrigation field conditions were L3 x T4 (015114 x EV-6098), L9 x T4 (015129 x EV-6098), L9 x T1 (015129 x Sahiwal-2002). These crosses might be useful as transgressive seggregants in subsequent generations. The lines viz 014955, 015084, 015114, Sahiwal-2002, Agaiti-2002, Ev-5098 and Ev-6098 were found as best parents. These lines may be exploited in future breeding program for drought conditions. On the basis of different inheritance pattern of each parameter, it was suggested that overall performance of the lines and their all possible combinations might be more useful while selecting for water stress condition.