Emergence and Growth Characteristics of Sorghum and Pearl Millet Intercropped with French Beans after PEG-based Seed Priming under Greenhouse and Phytotron Conditions

Abstract

In order to study the performance of primed sorghum and millet seeds under intercropped or monocropped planting systems, and to investigate the possibilities of enhancing the osmotic effects of polyethylene glycol (PEG) with salt or growth regulator additives, two experiments were conducted in the greenhouse and phytotron. Intercropping primed seeds with Phaseolus vulgaris L. did not affect germination percentage but reduced germination speed as compared to primed, monocropped seeds. This was ascribed to effects of competition for water and to seed size. Neither priming treatment nor cropping system affected seedling growth in the genotypes studied. Priming treatments with PEG and other additives increased the speed of germination. The PEG and PEG + Sucrose treatments yielded the highest germination percentages, and PEG + GA_3 the highest germination speed. Mixing PEG with NaCl or ascorbic acid yielded lower germination percentages and longer germination periods.