Seed germination, seedling vigor and survival of papaya (Carica papaya L.) cv. 'Red Lady' under GA3 treatment and different nursery growing media

Slow, partial and uneven germination of papaya, along with high seedling mortality, are common challenges faced by papaya growers. Consequently, papaya is commercially propagated by seeds. This study aimed to enhance papaya germination and seedling success by testing various combinations of gibberellic acid (GA3) and nursery growing media under green shade net conditions. This experiment was conducted at the Department of Horticulture, Lovely Professional University (LPU), Jalandhar, Punjab from July to September 2022-2023. A field experiment was conducted using a factorial completely randomized design (F-CRD) with 16 treatments and three replications, comprising a total of 576 plants. The experiment involved in four levels of gibberellic acid: G0 (soaking in water), G1 (50 ppm), G2 (150 ppm) and G3 (250 ppm). Additionally, four levels of nursery growing media-GM0 (soil), GM1 [soil: vermicompost (1:1)], GM2 [soil: cocopeat (1:1)] and GM3 [soil: cocopeat: vermicompost (1:1:1)] and their interactions were evaluated. The results revealed that among gibberellic acid treatments G3 (GA3 250 ppm) significantly outperformed other treatments in terms of seedling parameters. Regarding the individual effect of nursery growing media, the maximum seedling parameters were observed under treatment GM3 [soil: cocopeat: vermicompost (1:1:1)]. Among the interactions of GA3 and nursery growing media levels, all seedling parameters, except petiole length, were significantly superior in treatment G3 GM3. Meanwhile, treatment G2 GM3 was statistically at par with it for most of the seedling parameters studied. These findings suggest the potential of this treatment combination for improving papaya seedling success in a new environment, specifically under Punjab climatic conditions.