Abstract
This research was conducted to create a plant-available nitrogen nutrient solution utilizing ruminant bacteria for ultimate use as a liquid nitrogen fertilizer for precision fertigation of vegetable crops. Three hyperammonia-producing ruminant bacteria, Clostridium aminophilum, Peptostreptococcus anaerobius, and Clostridium sticklandii, were cultured anaerobically using five different organic nitrogen substrates to determine their efficiency in producing bioammonium/ammonia (BAA), a term defined here as a biologically produced solution containing both ammonium and ammonia. These bacteria were chosen because of their ability to produce ammonium at rates not experienced by any other bacteria. The five substrates were soy protein isolate (SPI), blood meal, feather meal, dried fish, and yeast extract (Y) used alone and in combination with Y. C. aminophilum and SPI were selected for further experimentation in an attempt to maximize BAA production. These substrates were chosen because they are commonly fed to cattle and they are also used as organic fertilizer amendments. C. aminophilum was cultured with SPI rates from 0.8 g·10 mL(-1) salt solution reaching SPI's maximum solubility level at 1.6 g·10 mL(-1) salt solution at 0.2 g intervals, and the BAA content was measured every 24 h for 168 h. It was concluded that there was no significant benefit in culturing C. aminophilum with more than 1.0 g·10 mL(-1) for more than 96 h to achieve maximum BAA concentrations.