Application of Polyphasic OJIP Chlorophyll Fluorescent Transient Analysis as an Indicator for Testing of Seedling Vigour of Common Bean (Phaseolus vulgaris L.)

In many stored seeds, even though the standard germination stays high with storage time the field emergence may not always be so. This makes the standard germination test results questionable in a commercial setting. The OJIP test derived from the polyphasic transient fluorescence is used as a latest method to determine the quality of seeds. We tested the suitability of this test to determine vigour of seeds of two Phaseolus varieties. Seeds of two varieties were stored in bulk in two different packing materials at controlled temperature (17±1 °C) and relative humidity (52-55%) for one year, and the seed germination and the field emergence were evaluated once in two months. The OJIP chlorophyll fluorescence parameters were measured in the first two leaves of 5-day old seedlings. Standard germination test results were acceptable even after one-year of storage. However, field emergence percentage reduced over storage time. Analysed data showed that OJIP derived parameters; specific energy fluxes (ABS/RC, TR0/RC, ET0/RC), quantum efficiencies (Phi_P0, Psi_0 , Phi_E0) and performance index (PIABS) were significantly different with the storage period. PIABS did not differ significantly with variety and packing materials. PIABS significantly correlated with the field emergence. As the reduction of PIABS in the seedlings is due to the changes in physiological condition of the seeds at the seed storage, it can be used as a good indicator in assessing seed quality, seed vigour in particular.