Review paperStudy on effect of Plant Growth Promoting Rhizobacteria (PGPR) application on seed germination ability, seedling vigor and some related characters of late maturity Maize (Zea mays L.) hybrids

In order to study the effect of Azotobacter chroococcum, Azospirillum lipoferum and Pseudomonas fluorescen application on late maturity Maize (Zea mays L.) single cross hybrids (SC700, SC 704 and a promising single cross, B73×K18) seed germination ability and seedling vigor a laboratory research was conducted. Experiment treatments including hybrids seeds were single inoculated with one by one bacteria and co inoculated by two and three bacterial combined inoculants and no inoculation as control treatment. Also studied characters including: final germination percent, mean time to germination, mean daily germination, coefficient of velocity of germination, daily germination speed, seedling, primary root and shoot length, seedling, primary root and shoot dry matter and seedling vigor index were determined. Results revealed that except of mean daily germination and coefficient of velocity of germination, other studied traits affected by interactions of hybrids and Plant Growth Promoting Rhizobacteria. Likewise, revealed that application of an inoculants of three bacteria combination have highest growth promoting effect on germination ability and traits related to seedling vigor of all hybrieds and Azotobacter chroococcum and Pseudomonas fluorescens and seed single inoculation by those bacteria have most growth promoting effect respectively. Also, revealed that studied characters of SC704more than other hybrids affected by growth promoting effect of studied bacteria and respectively B73×K18 and SC700 affected by studied Plant Growth Promoting Rhizobacteria stimulating effect and studied characters have high correlation among them. Therefore, based on this research results application of studied Plant Growth Promoting Rhizobacteria have considerable effect on Maize studied hybrids seed seedling enhancement.