Hadacidin, a New Plant-Growth Inhibitor Produced by Fermentation

Publisher Website
Google Scholar
Abstract
The culture filtrates of Penicillium purpurescens and P. frequentans caused severe stunting of many plants and killed crabgrass when applied as foliage sprays. The active dwarfing component in each fermentation broth was isolated in crystalline form and identified as the sodium salt of N-formyl-hydroxyaminoacetic acid (hadacidin). Foliage sprays containing hadacidin caused dwarfing effects on pea plants inhibited root growth and delayed flowering without causing any contact injury. Sprays containing 125 to 500 mg/liter of hadacidin stopped the expansion of the young leaves of bean plants and inhibited stem elongation for 1 week, but this was followed by an enhancement of stem elongation the second week. Hadacidin was ineffective when applied to the soil, but it inhibited root growth and stem growth when it was applied to the roots of tomato plants growing in nutrient solution. Hadacidin counteracted the enhancing effect of another fungal product, gibberellic acid, on stem elongation and leaf enlargement of pinto bean plants.