Effect of Gibberelun in inducing alteration of flower sex ratio in jatropha curcas

摘要

A field experiment was conducted at the School of Sustainable of Agriculture in Universiti Malaysia Sabah, Sandakan, Sabah to determine the effect of gibberellinsudconcentration on the flower sex ratio and yield of Jatropha curcas. The experimental design was using Completely Randomized Design (CRD). This study was done using four levels of treatments, a ppm (control), 50 ppm, 100 ppm and 150 ppm of gibberellin at which each treatment were replicated 6 times. The spraying was done for three times with the interval of five days on the Jatropha flower buds. Data was collected from the day of last spray on the flower buds until the fruit development. The results were analyzed using various analyses such as One Way ANOVA, IndependentSamples T-test, and also descriptive analysis through SPSS version 21 software. Although the study showed that increase in gibberellin effect increase the meanudnumber of female flowers which lead to alteration on the flower sex ratio but could not be proven through statistical analysis as it shows not significant result at 5% of significant level. Whereas, result on flower sex ratio showed that gibberellin has caused alterations. However, the alteration did not increase the ratio but reduced after being treated with gibberellin. This is due to large difference between the mean values of male and female flowers on treated plants lead to reduction in the flower sex ratio being reflected. Application of 50 ppm and 100 ppm of gibberellin shows good effect on the number of flowers and fruits development. Application of 150 ppm of gibberellin increased mean number of female flowers but does not translate to higher fruit yield compared to fruit yield produced form concentrations of 50 ppm and 100 ppm. Therefore, treating with gibberellin would be efficient in increasing flower and fruit yield, although increase in number of female flower and number of fruits could not be proven through statistical analysis. This study could be tried with other types of plants to find out whether this result would be applicable for them.