IBA Induced Rooting and Growth Response of <I>Jatropha curcas</I> L. Cuttings under Normal and Salt Stress Conditions

Abstract

A pot culture experiment was conducted to evaluate the effect of salinity and IBA treatment on cuttings of Jatropha curcas L. in relation to sprouting of buds, initial growth parameters, rooting and survival. The performance of Jatropha curcas L. was better in S_N (Natural soil) and decreased in all salinity levels. The highest per cent sprouting of buds was recorded under S_N (Natural soil) and minimum in S₅ (10 dSm^-1) in IBA treated cuttings, while no sprouting of buds was observed under the salinity level S₅ (10 dSm^-1) in untreated cuttings. IBA treated cuttings have higher survival and rooting when compared with their respective untreated cuttings (control). The maximum per cent survival and rooting was observed under natural soil (S_N). The salinity levels of S₃ (6 dSm^-1) and beyond greatly declined the survival and rooting in IBA treated as well as untreated cuttings (control). Increasing salinity levels also suppressed the growth parameters viz., number of leaves per plant, root length, leaf area, and biomass production in IBA treated cuttings as well as untreated cuttings (control). However, the reducing effect was more pronounced in untreated cuttings when compared to IBA treated cuttings. The salinity level of S₃ (6 dSm^-1) and beyond greatly reduced the above parameters in both untreated and IBA treated cuttings. Thus the present study reveals that the untreated cuttings of Jatropha curcas can be planted in the soil up to salinity level of 2 dSm^-1, whereas, if treated with IBA the cuttings can be planted up to a salinity level of 4 dSm^-1