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NATURALLY OCCURRING AUXINS AND INHIBITORS AND THEIR ROLE IN FRUIT GROWTH OF AONLA ( EMBLICA OFFICINALIS GAERTN.)
Author(s) -
RAM SANT,
RAO T. RAJA
Publication year - 1981
Publication title -
new phytologist
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.742
H-Index - 244
eISSN - 1469-8137
pISSN - 0028-646X
DOI - 10.1111/j.1469-8137.1981.tb04567.x
Subject(s) - auxin , dormancy , shoot , abscisic acid , apical dominance , biology , botany , horticulture , germination , biochemistry , gene
Three acidic (a 1 , a 2 and a 3 ) and two non‐acidic (a 4 and a 5 ) auxins were detected in the immature fruit of aonla ( Emblica officinalis Gaertn.). Chromatographic studies coupled with bioassays led to the tentative identification of a 2 , a 4 and a 5 as IAA, IAAld and IAN, respectively. Two growth inhibitors (R 1 and R 2 ) were also detected in the fruit. These behaved like naringenin and abscisic acid, respectively, in paper and thin‐layer chromatography. The inhibitors R 1 and R 2 were present in low concentrations in dormant fruits and did not appear to be the cause of dormancy. The factor playing a major role in the dormancy mechanism of the fruit appears to be auxin. Concentration of auxin increased in the fruit with the onset of dormancy and decreased to a low level prior to dormancy break. Shoots grew while fruits were dormant and dormancy break in fruits occurred after cessation of shoot growth. Since rise and fall in the rate of shoot growth corresponded with the period of rise and fall in the auxin content of dormant fruits and since shoot‐tips and dormant fruits contained identical auxins, it is proposed that the auxins translocated from the shoot‐tip to the fruit cause dormancy of fruits by a mechanism similar to that operative in apical dominance.