Effect of Microbial Inoculants on Plant Attributes and Nutrients Uptake by Soybean in Vertisols

The present study was carried out during kharif season 2019-20 at the Research Farm, Department of Soil Science & Agricultural Chemistry, Jawaharlal Nehru Krishi Vishwa Vidyalaya, Jabalpur, Madhya Pradesh (INDIA), to assess the effect of microbial inoculants on plant attributes and nutrients uptake by soybean in Vertisols. The experiment was laid out under randomized block design (RBD) with three replications. The 15 treatments comprised of different beneficial microbial consortia in possible combinations applied as seed treatments. The crop was supplemented with recommended dose of fertilizers 20 N : 80 P2O5 : 20 K2O kg ha-1. Besides these, two control plots were maintained as fertilized un-inoculated control (FUI) and unfertilized un-inoculated control (UFUI). The findings revealed that the significant improvement were noticed by the application of consortia NPK+EM+PGPR in plant growth attributes of nodulation at 25, 45 & 65 DAS (71, 70 & 59% respectively), over control (9.5, 33.4 & 34.7 nodule plant-1) and its biomass, (62, 69 & 74% respectively),over the control (0.58, 1.16 & 0.99 g plant-1), plant height at 25, 45 & 65DAS were increased 61, 40, 41% respectively, over the control (16.20, 34.90 and 44.30 cm) and plant biomass, (48, 62 & 53%), over the control 1.67, 4.73 and 6.1 g plant-1. Similarly, nutrient uptake (seed & stover) were also increased at 25, 45 and 65 stages of crop growth, with 36.6, 34.8 & 51.3% in seed and 66.7, 98.2 & 67.2% in straw respectively over the control (98.5, 63.8, 5.2, and 7.4, 24.9 and 44.4 kg ha-1 respectively). Thus, it may be concluded that the consortium of NPK + EM + PGPR was superior for sustainable crop production and soil health.

Phenotypic and microsite plant individual variation determine the pollination network structure and its functional consequences

The biotic and abiotic context of individual plants in animal-pollinated plant populations may influence pollinator foraging behaviour and therefore how the pollen flow occurs. Thus, this variation among conspecifics within a given plant population can ultimately influence the plant reproductive success. Here we used a fine-scale, well characterized population of Halimium halimifolium in combination with exponential random graph models (ERGMs) to assess how the intrapopulation variation in intrinsic (i.e. phenotype and phenology) and extrinsic (i.e. microsite) plant attributes configures individual plant-pollinator networks and its functional consequences. We found that pollinator visitation patterns and the emerging network configuration were associated with both intrinsic and extrinsic plant attributes, such as the number of flowers, the flowering synchrony and the cover of intraspecific and interspecific neighbours. Both intrinsic and extrinsic plant attributes also affected the plant female reproductive success directly and indirectly - through its effects on the probability of conspecifics plants to share pollinators. Our study opens up new approaches to assess and predict the functional consequences of context-dependency in plant-pollinator interactions, especially under global change scenarios, where the ecological context of individual plants is likely to change.