Abstract
The plant height, base diameter, leaf number, leaf area, petiole length, adventitious root ( initiarion, growth and branching habit ), periderm formation in the stem and root, anatomical features of the root ( normal and adventitious ) leaf ( lamina and petiole ) and disorganization of tissues were studied in Corchorus capsularis and C. olitorius grown under various water regimes. The cultivars CVL-1 and D-154 of C. capsularis, and 0-4 and R-26 of C. olitorius were grown under drought, saturated soil, saturation and drought conditions of soil moisture, artificial incessant rain and different levels of standing water ( 5, 10, 20 and 30 cm ). For anatomical studies the paraffin method of microtechnique was followed. In consideration to most of the growth features, the cultivars 0-4 had been found to be tolerant to drought but susceptible to waterlogging condition, particularly at the young stage. On the tolerance of submersion, the test cultivars could be placed as D-154 > CVL-1 > R-26 > 0-4. On the basis of number of adventitious roots per sq. cm. and their lengths, the cultivars were ranked as D-154 > CVL-1 > R-26 > 0-4. The adventitious roots were uniformly thick in CVL-1 but thin and sharply tapering in 0-4. The primary and secondary structures of the roots of all test cultivars showed resemblance to those of the tetrarch dicotyledonous root. Gross anatomical structures of the 3-week-old stilt root of an 0-4 plant were described for the first time. The stilt root showed both shoot and root like features. adventitious root showed primary structures with 4 or 2, sometimes 3 and rarely 5 vascular bundles. The chlorenchyma gave rise to phellogen in the stem. In the roots of all four test cultivars and in some cases of 0-4 stem, the phellogen was developed from deep cortical tissue. Irrespective of the cultivars, there was fully formed periderm in the stem and root of older plants. No remarkable structural change Was noticed in the lamina and petiole of the plants, grown under drought and standing water. The disorganization and degeneration of cortical tissue, formation of lysigenous air spaces and dissolution of corner thickening of collenchyma were observed while the plants were grown under incessant rain and standing water. In drought condition, the cells became thick walled. When the jute plants are exposed to drought after submergence, the quality of fibre deteriorates due to adherence of periderm to the fibre bundles.