Turnover of cell wall components during sink development in seeds of three cotton genotypes

R.K. Sharma

Department of Biosciences, Saurashtra University, Rajkot 360 005 Gujarat (INDIA) (India)

V.S. Thaker

Department of Biosciences, Saurashtra University, Rajkot 360 005 Gujarat (INDIA) (India)

Abstract

Size of the cells in developing seed is one of the major factors that regulate yield potentials. Seed of three cotton genotypes, Gossypium hirsutum. L cv (H-4; H-8) G. herbaceum L. cv (G. Cot-15) exhibits variation in their final seed size (large, middle and smaller) were studied for growth and changes in cell wall components during entire period of seed development. High and low molecular weight xyloglucan contents were extracted with 1M and 4M alkali, respectively. Initially the high and low molecular weight xyloglucan contents remained low and increased when cell size stabilized. Changes in esterified and non-esterified pectic substances were also fractionated from the cell wall of developing seed and theirs role in cell elongation phase is discussed. It was observed that bigger seed has higher xyloglucan contents than that of middle and smaller sized seed. Pectic substances were higher during elongation phase in all genotypes. The role of these polysaccharides in sink size development is discussed.

Keywords:

Cotton seeds, Gossypium Pectic substances, Sink size, Water amount, Xyloglucans