IJSRP, Volume 3, Issue 12, December 2013 Edition [ISSN 2250-3153]
Msaakpa, T. S., Obasi, M. O., Kalu, B. A.
Abstract:
A field study was conducted at the Teaching and Research Farm, University of Agriculture, Makurdi, in 2008 and 2009 cropping seasons. The objective was to determine the effects of six selected growth regulators viz: 2, 4-dichlorophenoxyacetic acid (2, 4-D), aluminum tetraflouride (AIF4), fusicoccin, ethrel (2-chloroethyl phosphonic acid) – both at 200mg/L; coconut milk and potassium nitrate (KNO3) at 15% each, on the growth of four castor accessions namely; LAF-4, LAF-11, AKW-5 and AKW-7. Observations on growth were recorded on leaf area index (LAI), absolute growth rate (AGR), net assimilation rate (NAR), number of leaves and plant height – all per plant at 4, 8, 12, 16, 20, 24 and 28 weeks after sowing. The technique of growth analysis described by Steel and Torrie was adopted for data collection. Results showed that all the growth parameters were significantly affected by growth regulators and castor accessions at all growth stages, and were higher when castor accession were treated with 15% of coconut milk. Castor accessions varied significantly in growth being higher in AKW-5 at early growth stages and LAF-4 at latter growth stages. The 15% of coconut milk and AKW-5 interaction produced significantly higher growth at 8 to 24 WAS than other growth regulators and castor accession interactions. AKW-5 showed greater growth response to application of 15% of coconut milk.