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Sixty-nine rhizobacteria isolated from chickpea rhizosphere were screened for their antagonistic potential against Fusarium oxysporum f. sp. ciceris under in vitro condition. Of these, 30 isolates inhibited growth of the pathogen and 13 potent antagonists were assessed for their functionality traits. Among the antagonistic traits exhibited by antagonists, production of diffusible antimetabolites insured its inhibitory effect on growth of test fungus as well as spore germination on solid media. Inhibition of fungus biomass in broth-based dual culture was revealed by 11 antagonists, while metabolic extracts of 5 isolates reduced the radial proliferation on solid media. Implication of biocidal volatiles in antagonism was demonstrated by 11 isolates; 3 produced cyanogenic volatiles, while all were ammonia producers. Investigation for hydrolytic activity demonstrated production of chitinase by 4 isolates and β-1,4-glucanase by 11, while all were protease and amylase producers. Revealing the dual potential of bioantagonists, all the isolates tested positive for IAA and salicylic acid production, 7 for siderophore production while 10 were P-solubilizers and 8 Zn-solubilizers. Under glass house condition, bacterization of chickpea seeds with potential isolate Ps14c alone and in consortium with Mesorhizobium ciceris reduced wilt incidence in pots (soil amended with F. oxysporum) to 48 and 28%, respectively, as compared to uninoculated control (74%) and also recorded appreciable increase in growth parameters. Present investigation clearly reveals the potential of rhizobacteria for use as bioinoculants.

The antagonistic activity against Fusarium oxysporum f. sp. ciceris was determined for 40 chickpea rhizobacteria. Twenty eight isolates showed antagonistic activity against test fungus ranging from 18.2 to 41.8%. Characterization of the antagonistic attributes showed that all the antagonistic isolates produced diffusible and volatile antifungal metabolites in terms of growth inhibition, maximum being with the isolates 39P (77.8%) and 15B (64.2%), respectively. Nineteen of the isolates showed catechol and hydroxamate type siderophore production. All the isolates produced ammonia and twelve showed HCN production. On the basis of their antagonistic and PGP functionality traits, five isolates (2B, 7B, 28P, 34P and 38P) were selected for glass house studies on two chickpea varieties (JG-62 and GPF-2). Isolates 28P, 34P and 38P were found to be most promising for wilt control and plant growth promotion. Isolate 38P reduced the wilt incidence to 44.6% which was at par with fungicide treatment (55.5%) and had a significant edge over negative control (85%) in the chickpea variety JG-62. Similar trend of wilt incidence was observed in GPF-2 variety. Green house experiments on two varieties of chickpea JG-62 and GPF-2 showed that seed treatment with plant growth promoting rhizobacteria (PGPR) + Mesorhizobia had a synergistic effect in terms of disease control and growth promotion as compared to use of single bioinoculants, thus positively influencing plant microbe interaction. Key words: Antagonism, chickpea, Fusarium, plant growth promoting rhizobacteria (PGPR), Rhizobium.

The experiment was conducted to study the effect of four levels of phosphorus (0, 20, 30 and 40 kg P2O5 ha-1) and four biofertilizer treatments [uninoculated control, Rhizobium, plant growth promoting rhizobacteria (PGPR) and Rhizobium + PGPR] on growth and grain yield of lentil. The experiment was conducted in factorial randomized complete block design (RCBD) with three replications. The periodic data recorded at 30, 60, 90, 120 days after sowing (DAS) and at harvest showed that the highest growth in various parameters i.e. plant height, branches plant-1 and shoot dry matter accumulation was recorded with application of 40 kg P2O5 ha-1, however, it was at par with 30 P2O5 ha-1. Among the biofertilizers, Rhizobium + PGPR treatment gave maximum values of growth parameters like plant height, branches plant-1 and shoot dry matter accumulation at all the stages. At 30-60 DAS, the maximum crop growth rate (CGR) was recorded with the application of 40 kg P2O5 ha-1 (71.3 kg ha-1 day-1) and co-inoculation of Rhizobium and PGPR (72.0 kg ha-1 day-1). Application of 40 P2O5 ha-1 and use of coinoculation (Rhizobium + PGPR) provided the highest grain yields. The study highlights the importance of phosphorus application and biofertilizers inoculation for improving the growth and grain yield of lentil.

The present investigation was conducted to evaluate the effect of plant growth promoting rhizobacteria (PGPR) cultures on the activities of antioxidant enzymes in brinjal seedlings. The treatment with these PGPR cultures enhanced the activities of these enzymes. The brinjal seedlings inoculated with PGPR7 (Bacillus spp.) showed maximum activity of superoxide dismutase, catalase and amylase. Minimum peroxidase activity was observed in the seedlings treated with PGPR2 (Pseudomonas spp.). Based on the results of the experiment, the use of plant growth promoting rhizobacteria treatment may provide a means of preventing the oxidative stress in plants by enhancing the activities of antioxidant enzymes.

Nodal anatomy of 14 species belonging to 10 genera of Bignoniaceae is described. Unilacunar is the basic nodal pattern for the family with triple and multi-traced condition. The former type is observed inCampsis grandiflora, Pyrostegia venusta, Doxyantha unguis-cati, Stenolobium stans, Tabebuia pentaphylla andTecoma spp., while the latter is found inAdenocalymma alliaceum, Haplophragma adenophyllum, Jacaranda mimosifolia, Millingtonia hortensis, Spathodea campanulata, Tecoma capensis andT. jasminoides. Parmentiera cereifera has an arc of vascular elements passing through the single gap. Phylogenetic aspect of nodal anatomy is discussed.

The petiolar anatomy of sixteen species belonging to fourteen genera of Bignoniaceae has been studied. Two aspects, namely, the vascular pattern in the slender part of the petiole and the mode of vascular supply from the primary rachis to leaflets or secondary rachii, are taken into consideration. On the basis of the vasculature as seen in transection of the slender part, four main types of petioles have been recognised, while there are three patterns of vascular supply. A key also has been devised to identify these sixteen species.