Study was conducted to isolate and characterize Rhizobia from root nodules of pigeon pea from Vijayapur, Kalaburgi and Bagalkot districts of northern regions of Karnataka. Ten Rhizobial isolates and reference strain PPM35B were subjected for nodulation test. All the isolates showed positive result for nodulation. The number of nodules was ranging from 12 to 14.5 per plant. All these isolates were also subjected for functional characterization. The amount of IAA, GA production and ACC deaminase activity by different rhizobial isolates ranged from 16.60 to 22.85 g IAA/ ml of broth, 11.00 to 14.43 g/25ml of broth and 44.5 to 73.5 nmoles of α-ketobutyrate/mg/h of broth respectively. The diameter of P, Zn and Si solubilization by the rhizobial isolates was ranged from 4.5 to 10.3 mm, 9.5 to 20.5 mm and 5.5 to 6.5 mm, respectively. These isolates were further subjected for morphological and biochemical characterization. All the isolates were found to be rod shaped and gram negative. All the isolates were positive for citrate utilization, catalase, urease, oxidase, acid and gas production tests whereas negative for Voges proskauer's and indole production test.
Chickpea (Cicer arietinum L.) is one of the most important pulse crop grown all over India. Chickpea wilt caused by Fusarium oxysporum f. sp. ciceri is one of the major disease on chickpea in Northern Karnataka, which is soil and seed borne. Heavy inoculum in the soil and favorable environment condition results in the death of infected plant and therefore total yield loss.In this study, three antagonists, and seven botanicals were studied against Fusarium oxysporum f. sp. ciceri causing chickpea wilt. In vitro studies found that among the botanicals, turmeric rhizome extract gave maximum per cent inhibition of mycelial growth (26.73%) and least per cent inhibition of mycelial growth (9.96%) was observed in cassia tora at 15 per cent concentration. Among the antagonists, Trichoderma harzianum was effective in per cent inhibition of Fusarium oxysporum f. sp. ciceri with (76.47%) and Pseudomonas fluorescens found least effective in per cent mycelial inhibition with (34.41%).
Background: Symbiotic nitrogen fixation plays a major role in the production of million tons of total biological nitrogen. The Rhizobium not only fixes the nitrogen but also produces plant growth promoting hormones. In this view, the present study was undertaken to characterize the native Rhizobium isolates for their functional properties and evaluate on pigeon pea for their plant growth promotional activities. Methods: The present investigation was carried out during the year 2018-19 at UAS, Dharwad. Five of the native isolates obtained from Northern district of Karnataka were subjected for functional characterization using standard methods. The isolates were also tested for their plant growth promotional activities.Result: The IAA production in the isolates was ranged from 20.50 to 22.85 mg IAA/ml of broth and GA production from 13.40 to 14.51 mg/25ml of broth. ACC deamination activity in the isolates was ranged from 57.50 to 75.5 nmoles of α-ketobutyrate/mg/h of broth. All the isolates exhibited their ability to solubilize P and Zn. Out of ten isolates, four isolates exhibited potential to inhibit mycelial growth of Fusarium oxysporum f. sp. udum and per cent inhibition was ranged from 48.75 to 73.75. All the isolates were found to be positive for siderophore and HCN production. The isolate AMVPR98 performed better with respect to all the growth parameters of pigeon pea. Molecular characterization of isolate AMVPR98 revealed 99% similarity with Rhizobium pusense strain AB3.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.