The Influence Of Light Duration On The Germination and Growth Of Gmelina arborea {Linn F.) Seedlings:- Francis, Victory C

ABSTRACT

The study was centred on the Influence of Light duration on The Germination & Growth of Gmeliiia arborea seedlings. Three treatments (No shade, mild shade and complete shade) were applied with three replicates ol each ofthe treatments. Data on height, leave number and root collar diameter was obtained at 2-weeks after planting, 4WAP, 6WAP, 8WAP, 10WAP and 12WAP. Data collected was analyzed using Analysis ofVariance and Means were separated using Duncan Multiple Range Test. The results showed that emergence and height was observed from 6WAP. Under No shade, the height of6.83cm, 8.70cm, 12.06cm and 14.06cm was observed at 6,8,10 and 12WAP respectively while the height of2.4cm, 4.3cm, 5.56cm and 6.80cm was observed at 6,8,10 and 12WAP respectively under Strong shade and under Mild shade, the height of6.46cm,7.46cm, 12.00cm and 14.33cm was observed at 6,8,10 and 12WAP respectively. The mean number of leaves under the No Shade treatment ranged from 6.33 (6WAP) to 12.67(12WAP). Also the mean number ofleaves under the Strong Shade treatment ranged from 2.40 (6WAP) to 7.00(12WAP). Lowest Mean leave number value of 6.00 was obtained under the Mild shade treatment at 6WAP while the highest leave number value of 10.67 was obtained under the Mild shade treatment at 12WAP. Under shade, the collar diameter of 1.00cm, 1.20cm, 1.33cm and 1.63cm was observed at 6.8.10 and 12WAP respectively while the collar diameter of 0.26cm, 0.43cm, 0.50cm and 0.93cm was observed at 6,8,10 and 12WAP respectively under strong shade. Under mild shade, the collar diameter of 0.83cm, 0.91cm, 0.70cm and 1.13cm was observed at 6,8,10 and 12WAP respectively. The height, leave number and collar diameter values obtained under No shade and Mild shade were not significantly (P<0.05) different for period ofthe study but were significantly (PO.05) higher than that obtained under Strong shade. Based on the findings ofthe study, it can be concluded that Gmelina arborea emergence is delayed for the first four- weeks and visible growth is observed from 6 weeks after planting. Also, the germination and seedling growth is threatened by absence oflight but growth is enhanced in the presence oflight. This applies to the growth parameters such as number ofleaves, height and collar diameter. Based on the findings of the study, it is recommended that shade should be avoided in situations of mass production of Gmeliiia arborea seedlings for afforestation or reforestation purpose.