Abstract
Piriformospora indica is an endophytic fungus that colonized monocot as well as dicot. P. indica has been termed as plant probiotic because of its plant growth promoting activity and its role in enhancement of the tolerance of the host plants against abiotic and biotic stresses. In our recent study, we have characterized a high affinity phosphate transporter (PiPT) and by using RNAi approach, we have demonstrated the involvement of PiPT in P transfer to the host plant. When knockdown strains of PiPT-P. indica was colonized with the host plant, it resulted in the impaired growth of the host plants. Here we have analyzed and discussed whether the growth promoting activity of P. indica is its intrinsic property or it is dependent on P availability. Our data explain the correlation between the availability of P and growth-promoting activity of P. indica.