Phosphorus In Plant Essay

1. Introduction

Phosphorus (P) is vital for the growth of plants and is the second major macro-element after nitrogen, which limits plant growth (Gyaneshwar et al., 2002). Most of the soluble inorganic phosphate is applied annually to the soil as a chemical fertilizer, which is immobilized quickly and again becomes inaccessible to plants. Hence, the lower amount of soluble P in soil is one of the limiting factors for agronomic crop production. Fertilizers (microbial inoculant) offer a solution, as they not only revitalize the soil, improving soil fertility, but also a powerful tool for increasing efficiency (Minaxi et al., 2012) and reducing soil diseases. Furthermore, its application is one of the most economical strategies developed to assist

The crop occupies 12.1% of total pulses area and 8.8% of total pulse production in India with an average national productivity of 518 Kg/ha. Because of its relative tolerance to drought, a short life cycle (75-90 days) and the ability to fix atmospheric nitrogen, it is cultivated as a component in various cropping systems, chiefly with rice and wheat (Kaewwongwal et al. 2015). Soil amendments that increase soil fertility and plant productivity can be very useful for crops. An improved crop yield by inoculation with a phosphate solubilizing fungal strain has been observed in many field studies. Thus, during the present investigation the facts that the inoculation of PSF has a positive effect on the growth and productivity of plants, has led us to in vitro and pot experiment studies to observe the ability of Aspergillus niger K7 in the growth, yield and nutrient absorption of plants against the soil

The flasks without inoculum served as control and were incubated in triplicate at 28±2°C for 14 days in an orbital incubator shaker at 130 rpm. The samples were collected after every 48 h to evaluate soluble phosphorus in the culture supernatant following the molybdenum-blue method of Murphy and Riley (1962). pH of sample was also recorded using a pH meter.

2.4 Culture Identification

For the molecular identification of K7 strain, total DNA was extracted by using ZR Fungal/Bacteria DNA kit (Zymo- Research Corporation, CA, USA) Mini Prep following the manufacture’s standard protocol. Thereafter, the amplified fragments were sent to NFCCI, Agharkar Research Institute, Pune, India for DNA sequencing.

2.5 Soil analysis

Soil of experimental field was analyzed for pH and available P. pH was measured using pH meter and method of Olsen et al. (1954) was used for the determination of available P.

2.8 Plant-soil experiment set