Water harvesting method, Nitrogen-Phosphorus fertilizer, Date palm variety, and leaf number
A field experiment was conducted to study the effect of water harvesting methods, NP - fertilizer rate on leaf number of some young date palm plants over a period of 32 months (May 2004- December 2006).The trial was sited at the Date palm Research Sub-station of the Nigerian Institute for Oil palm Research (NIFOR) Dutse (11o50’N, 09o25’E) in the Sudan savanna ecological
zone of Nigeria. The treatments consisted of six water harvesting methods (standard 30cm radius basin, single side pit, double side pits, perimeter square basin, side square basin and double square basin). Six NP-fertilizer rates (control which is zero level fertilizer, 20g N + 10g P, 40g N + 20g P, 60g N + 30g P, 80g N + 40g P and 100g N + 50g P) and six date palm varieties (Palm 300, Tirgal,
Dan Mali, Deglet Noor, Shuwarin C and Shuwarin B) arranged in a Latin square design. Two plants per experimental plot were sampled for plant leaf number, giving a total of 72 plants. Results from this study revealed that the effects due of varying water harvesting methods were not significant on leaf number. The effects due to varying NP-fertilizer rates were also not significant on leaf number. A three year experiment was not long enough to cause pronounced effects. Deglet Noor
and Dan Mali significantly recorded more leaf number while Shuwarin B, Tirgal and Palm 300 recorded the lowest leaf number. Application of NP- fertilizer at rates 80- 100g N and 40- 50g P/ plant/year on a three year Deglet Noor or Dan Mali date palm variety will enhance plant leaf number and yield and may be recommended for better date palm production, within the Sudan
ecological zone of Nigeria where this experiment was conducted, following further studies.