In endosperm during germination

Fig. 4.—Disappearance of Galactomannan from the Endosperm, and Appearance of Starch in the Cotyledon, During Germination of Seeds olTriganella foenum-graecum that had Already Been Soaked for 24 Hours at 24-26°. (Adapted from Figs. 5 and 6 of Ref. 199.)...

The gum is contained in a portion of the seed call endosperm. This is the food reserve for development of the embryo during germination. As the seed is dicotyledonous, you have two for each seed endosperm. The endosperm is surrounding the embryo and a shell of a blackish brown color surrounds these. In the severe case of impairment, the seed turns black and rubber and performance is very low when the gum contaminated with yellow spots to gray [26]. The Tara seeds measure 0.6 to 0.7 cm. and endosperm are 22-24% of the seed weight. The endosperm is crushed and sold as Tara gum. 

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