Some factors affecting the in vitro storage of "succari" orange cultures at normal growth conditions [electronic resource].

Includes references.

This work explores the possibility of using in lJitro techniques to store the shoots of "Succari" orange (Citrus sinensis L). In this study both the media composition and the vessel type were investigated. The shoot cultures were stored up to 36 month (without subculturing) in normal conditions; (16 hr. light and S hr. dark, the light intensity was about 2500 Lux at cxplapts level at 25±2°C). Media consisted of, MS at full strength without growth regulators (MSF); MS at half strength without growth regulators (Y2MSF) and MS at full strength plus (mgr1 ) 0.4IBA, I.OBA, 126 phloroglucinol. The same tested media were used in different culture vessels. The vessel types were test tubesJ5xl50mm (Tf.), glass tubes 25x 80 mm 25 x 150 mm (GT.), glass jars 200m1 and 350ml (GJ.) and conical flask 100m! (CF.). Data were recorded every 12 months storage period. The highest survival percentages were recorded in GT.25 x 150mlO & cr. filled with MSF and in IT 15 x 150 mm & 25 x 80 mm which were filled \\~th YzMSF, while the other vessels (GJ 200ml and 350ml) had recorded the lowest survival percentage during the storage period (36months) especially with MSH. Shoots stored in a small container for 36 months (such as IT, GT 25x 80, 25xl50 mm and CF.) showed good healthy appearance. Regarding the length o( the original shoots, the highest length was recorded with CF. filled with MSF and the lowest length was recorded when GJ. 350ml filled with MSH was used. The highest number of leaves was found when the GT.25x 80 mm and 25x150 mm filled with MSH or the GJ.200 ml filled with MSF were used. The lowest number was recorded with GJ. 350ml plus MSH. The highest number of new shoots was recorded with CF. filled with MSF, however the lowest number was in GJ. 350 ml with the same medium. Regarding the length of new shoots, the highest length was in CF. with MSF and GT.25x gOmm with MSH while the lowest one was recorded with GT 25x150mm with Y:! MSF. In recovery experiment, the growth rate was slow in the first subculture after storage, then it was increased gradually during the second and third subcultures. It was evident that shoots cultured in large volume vessels during storage was more efficient in proliferating shoots during recovery compared to shoots cultured in small storage one.

Summary in Arabic.

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