In Vitro Seedling Growth Of Adlay (Coix Lacryma-Jobi L.) 'Pulot' And Its Response To 2,4-Dichlorophenoxyacetic Acid, Benzylaminopurine, Plain Cow Dung Ash And Agnihotra Ash

Adlay (Coix lacryma-jobi L.) is an emerging alternative cereal crop which may benefit from plant tissue culture approaches. In this study, the morphogenic response of mature embryos of adlay to 2,4-dichlorophenoxyacetic acid (2,4-D; 1-3 ppm) and benzylaminopurine (BAP; 1-3 ppm) in Murashige and Skoog (MS) basal medium was screened in vitro. Further, agnihotra ash (AA) and cow dung ash (CDA) were evaluated as unconventional culture media additives. A sterilization procedure was first developed for mature embryos of adlay by varying sodium hypochlorite (NaOCl) concentration and the duration of surface sterilization. NaOCl at 1% (v/v, Chlorox (R)) using double sterilization (7 min: 8 min) was effective for surface disinfection of dehusked adlay seeds. In terms of plant growth regulators (PGRs), BAP and 2,4-D enhanced shoot growth in lower doses, but primary root growth was inhibited. Retarded shoot and root development were observed even at the lowest 2,4-D concentration and as BAP was increased. Yellow, compact callus was observed surrounding the mesocotyl and white crystalline and loose callus around the radicle region. Both types of calli appeared non-embryogenic and were most frequent at 2 and 3 ppm 2,4-D regardless of BAP concentration and ash additives. As for ash additives, application of 0.01% cow dung ash, 0.01% agnihotra ash and 1% cow dung ash resulted in larger seedlings compared with 1% agnihotra ash in basal media, although these differences were not pronounced in the plant growth regulator (PGR) background. Agnihotra ash and cow dung ash as miscellaneous additives may provide cost savings in plant tissue culture; further work is warranted.