Responses of in vitro raised bitter gourd plantlets to arbuscular mycorrhiza fungal species

Acclimatization of micropropagated plants corresponds to a transition period when roots become adapted to a substrate with less available nutrients, and to an autotrophic condition. To ameliorate this problem in bitter gourd, 30-day-old, in vitro rooted plantlets of bitter gourd cultivars Pusa Do Mausami, Pusa Vishesh and the DBGy 201 were subjected to root inoculation with different arbuscular mycorrhiza fungal (AMF) strains. All the mycorrhizal treatments showed almost two times higher ex vitro survival than the control plantlets. Mycorrhization plantlet showed increase in vine length in Pusa Vishesh (194.02 cm) in mixed strain, leaf area in Pusa Vishesh (107.91 cm²) in Acaulospora scorbiculata, chlorophyll in Pusa Do Mausami (3.29 mg/g FW) in A. scorbiculata) and total phenols content in Pusa Do Mausami (7.84 μg/g FW) in E. columbiana). Photosynthetic rates were enhanced in arbuscular mycorrhizal fungi (AMF) treated plant in Pusa Do Mausami (10.75 μmol CO₂/m²/s¹) in mixed strain in comparison to an uninoculated control. Among the AMF species, mixed strain (Nutrilink^®) showed good as high as 38% root colonization for all the cultivars. In this experiment the mixed AMF strain has contributed significantly in survival of the plantlets and plant establishment in the field.