Induction of parthenocarpy in dog rose (Rosa canina L.), persimmon (Diospyros lotus L.) and firethorn (Pyracantha cocineae Roemer) by the application of growth substances

Induction of Parthenocarpy in Dog Rose (Rosa canina L.), Persimmon (Diospyros lotus L.) and Firethorn (Pyracantha coccineae Roemer) by the Application of Growth Substances In this study, indole-3 -acetic acid (IAA) in concentrations of 10 and 100 ppm and gibberellic acid (GA) in concentrations of 200 and 500 ppm were applied in the bloom sta ges of flowering in dog rose (Rosa canina), persimmon (Diospyros lotus) and firethorn (Pyracantha coccineae). And the effects of these growth regulators on seedless fruit ( parthenocarpic fruit) set were investigated. In addition, the some morphological and bi ochemical changes were also investigated during development of parthenocarpic fruits. The results showed that GA induced parthenocarpic fruit set in R. canina and D. lotus, but IAA only in D. lotus. IAA and GA have not only any effect on the seedless fruit set in P. coccineae. GA caused a decrease in the fresh mass and size of both fruits of R. canina and D. lotus in addition IAA induced an increase in the fresh mass and size in part henocarpic fruits of D. lotus. GA also increased pedicels and hipanthium lengths in R. canina. Maturation of seedless fruits was earlier than the seeded fruits. Ascorbic acid con tents significantly increased in parthenocarpic fruits of D. lotus (treated IAA and GA) and hipanthium of R. canina sprayed GA and IAA. In all fruits, IAA and GA applications (except low concentrations of growth regulators in R. canina) decreased levels of total phe nolic substances. In addition, the growth regulators increased total carbohydrate and reducing sugar contents in R. canina, D. lotus and P. coccineae. Carotenoid contents in creased in the fruits of D. lotus and hipanthium of R. canina but it was not changed a lot of in P. coccineae sprayed the growth regulators. The highest changes of protein levels were observed in the hipanthium of R. canina sprayed IAA and GA. Consequently it has been found very important changes in metabolism during parthe nocarpic fruit set in R. canina and D. lotus since parthenocarpic fruits have a rich organic content, it has also been found that parthenocarpic fruits have higher quality than seeded fruits. Key Words: Dog Rose, Persimmon, Firethorn, Gibberellic acid, Indole-3 -acetic acid, Parthenocarp fruit vm