Gibberellin-induced perturbation of source–sink communication promotes sucrose accumulation in sugarcane

Abstract

Constant removal of sugars from the site of synthesis (i.e., leaves), in response to elevated sink (culm) demand, may perhaps prevent damping of photosynthesis, by sugar, and hence promote further sucrose accumulation in the culm. In this study, gibberellic acid (GA) induced nearly 42.3% enlargement in cell size and about 39.3% increase in internodal length (sink capacity), 177% escalation in reducing sugar level (sink strength), amplified the expression of sucrose-metabolizing enzymes (sink demand), viz., 7.5-fold for SAI, 4.5-fold for CWI, sixfold for SPS, all demonstrating facilitation of augmented sucrose accumulation in the culm. The GA-treated BO 91 cane (late maturing sugarcane variety) exhibited an elevated final sucrose concentration (40.54-41.6%) as compared to control (30.44-38.8%). The GA-sprayed cane of early maturing Co J64 also showed such a boost, but it was lost by the end of maturity, perhaps due to inversion and/or the less effective GA treatment. Thus, results demonstrated the role of GA in augmenting sucrose content of cane culm, possibly by influencing source-sink dynamics in sugarcane.

Ethylene-mediated improvement in sucrose accumulation in ripening sugarcane involves increased sink strength

“…The consequent realization that sucrose synthesis and accumulation in sugarcane is highly complex and that it may involve a large network of interactions operating at different levels of organization led to studies aimed at understanding the dynamics of gene and metabolic activities associated with sucrose accumulation at a more global scale [8, 13, 14]. The strong evidence of sucrose as a signaling molecule modulating a myriad of growth and developmental processes including cell division, cell differentiation and accumulation of storage products further strengthened this strategy [15, 16]. Microarray, transcriptomics and metabolomics studies on sucrose synthesis and accumulation in sugarcane internodes, though very limited in numbers, reported an association of sucrose level and the activity of a network of genes related to cell wall synthesis, stress responses, flowering, carbohydrate metabolism, lignin synthesis and sugar transport [8, 13, 14, 17, 18].…”

Dormancy Breaking and Stimulation of Apical and Basal Sugarcane Stem to Increase Multiplication Index

“…Hasil penelitian Barani et al (2013) menjelaskan bahwa perlakuan GA3 10 mg/l dapat meningkatkan kandungan gula total pada umbi kentang lebih tinggi dibandingkan perlakuan kontrol dan GA3 5 mg/l. Roopendra et al (2018) melaporkan bahwa GA3 dapat mempengaruhi dinamika source-sink yang menyebabkan kandungan sukrosa pada batang tebu meningkat.…”

Peranan GA3 terhadap Kerontokan dan Kualitas Buah Jeruk Pamelo Berbiji dan Tidak Berbiji

“…Penyemprotan GA 3 menambah kekuatan buah dalam menyerap fotosintat (Tuan et al, 2013;Roopendra et al, 2018). Hormon GA 3 menstimulus phloem loading/ unloading dikarenakan sink yang lebih kuat, mendorong aktivitas fructose-1.6-biphosphatase dan sucrose phosphate synthase (SPS) dalam meningkatkan sintesis dan ekspor fruktosa dan sukrosa serta meningkatkan ekstraseluler invertase dan gradien sukrosa melalui konversi sukrosa menjadi glukosa (Iqbal et al, 2011;Roopendra et al, 2018). Fruktosa, glukosa dan sukrosa merupakan komponen utama PTT pada jeruk (Li et al, 2019).…”