Correlation of epiphyllous bud differentiation with foliar senescence in crassulacean succulent Kalanchoe pinnata as revealed by thidiazuron and ethrel application

Correlations among Attributes of Senescence and Antioxidative Status of Leaf Discs during Epiphyllous Bud Differentiation in Kalanchoe pinnata Lam. (Pers.)

“…The pigment loss in discs with differentiating epiphyllous buds was faster than in those lacking buds. This could be explained on the basis of a source-sink type of relationship that exists between disc and the developing plantlet, as shown earlier (Jaiswal and Sawhney, 2006), resulting in a faster senescence in budded discs as compared to those without a bud. However, a somewhat reverse situation was observed in case of soluble proteins, for which a greater loss was recorded in budless discs.…”

“…It also acts as a recycler of nutrients from senescing cells to young leaves (Hörtensteiner and Feller, 2001;Lim et al, 2007). In vitro experimentation on epiphyllous bud differentiation has been shown to create conditions similar to senescence in the subten ding mother leaf disc that nourishes the growing plantlet (Jaiswal and Sawhney, 2006). Removal of the bud from the mother disc enhances the life span of the disc by several months (unpublished data), which could be related to a strong enzymatic and non-enzymatic antioxidative status prevailing in its tissues.…”

“…The diminishing Chl a+b content was found to be maximally correlated with alterations in the membrane protection. ferentiation but also accelerates foliar senescence, which appear to be correlative developmental phenomena (Jaiswal and Sawhney, 2006). The two developmental responses appear to be linked in the manner of a source-sink duo, especially during the early establishment phase of epiphyllous plantlets (Jaiswal and Sawhney, 2006).…”

“…ferentiation but also accelerates foliar senescence, which appear to be correlative developmental phenomena (Jaiswal and Sawhney, 2006). The two developmental responses appear to be linked in the manner of a source-sink duo, especially during the early establishment phase of epiphyllous plantlets (Jaiswal and Sawhney, 2006). In any case, senescence is characterized by a programmed recycling of nutrients (Hörtensteiner and Feller, 2001;Lim et al, 2007;Gregerson et al, 2008;Guiboileau et al, 2010).…”

“…In case of the biphasic types, the fi rst phase extends from initiation to the in situ development of morphologically mature but physiologically dormant buds, with the second phase leading to plantlet formation, triggered normally by leaf detachment, e.g. in Kalanchoe pinnata (Jaiswal and Sawhney, 2006). Leaf detachment in the latter case not only acts as a trigger for epiphyllous bud dif-…”