Author

Shukla Saluja

Abstract

Abstract: Growth is a unique biological attribute that normally follows a fairly identical pattern among similar organisms and their constituent organ systems. Young chickpea seedlings with intact cotyledons provide a unique model system to investigate a variety of growth correlative phenomena induced by selective organectomy and manifested through axillary bud outgrowth. The excision of shoot apex results in the development of a branch from the topmost leaf axillary bud whereas complete deshooting resulted in the development of a branch in the axil of each cotyledon. An additional removal of one cotyledon causes suppression of branch growth in the axil of the other intact cotyledon. This indicates that expression of the axillary branch growth is modified by persistent cotyledon. To understand the physiological mechanism of regulation of such multiorgan correlative growth responses, the seedling system was subjected to phytohormonal compounds like IAA, kinetin and Gibberellic Acid (GA). Some of the regulators brought about significant modulations of the axillary bud growth and resultant growth correlations. IAA and kinetin significantly inhibited growth of an intact seedling, and that of the non-suppressed branch in the deshooted seedling from which one cotyledon was excised. IAA also induced profuse rooting from the hypocotylar and cotyledonary nodal regions whereas kinetin induced multiple branches at the cotyledonary nodes. GA caused enhancement of growth of intact seedling and of the two axillary branches of unequal growth in the deshooted seedlings from which one cotyledon was also excised. The selected phytohormonal compounds tested were effective in modulating seedling growth, although they invoked diverse growth modulations in different cases.

Pages: 13-19

Doi Number 10.5958/2455-7218.2022.00051.1

Keywords Cicer arietinum, growth correlations, seedling growth, selective organectomy, phytohormones