The growth and yield response of cassava to Glomus fasciculatum (an arbuscular mycorrhizal, fungus)

Abstract

The beneficial effects of arbuscular mycorrhizal (AM) fungus, Glomus fasciculatum on the vegetative growth characters and yield of improved cassava (Manihot esculenta Crantz) are not well described.  Therefore a controlled experiment was carried out to evaluate the response of two improved cassava cultivars TMS 91934 and TMS 30572 to mycorrhizal application.  The experiment was arranged in a complete randomized design with three replications.  The plants were either inoculated with G. fasciculatum (Thax. Sensu Gerd.) or not.  Genotypic differences were observed and confirmed between the two cultivars whether inoculated or not.  It was evident from the results obtained that the two cultivars responded to the Am fungus; however TMS 30572 showed greater vegetative growth and yield response that TMS 91934.  The results also showed that the cassava plants responded to mycorrhizal inoculation as early as two to three weeks after planting.  TMS 91934 consistently produced more leaves, leaf area and numbers of stems.  Our studies also revealed that TMS 91934 diverted its photoassimilates to the shoot for maintenance of aerial parts rather than to the storage roots, whereas TMS 30572 diverted its photoassimilates more to the tuberous roots instead of maintaining higher leaf area.  It was concluded that due to positive growth and yield, use of AM fungus is beneficial for greater productivity of cassava.