Premium
Contribution of Cotyledons to Growth of the Sainfoin Seedling 1
Author(s) -
Cooper C. S.,
Fransen S. C.
Publication year - 1974
Publication title -
crop science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.76
H-Index - 147
eISSN - 1435-0653
pISSN - 0011-183X
DOI - 10.2135/cropsci1974.0011183x001400050036x
Subject(s) - seedling , cotyledon , biology , photosynthesis , dry matter , botany , dry weight , agronomy , horticulture
We studied growth of the sainfoin ( Onobrychis viciaefolia Scop.) seedling in three experiments designed to measure energy relationships during early seedling development and the photosynthetic contribution of the cotyledons. Growth of the sainfoin seedling depends on stored substrates during the first 7 days of growth. Stored substrate, however, was not adequate for normal first‐leaf formation and expansion, which appeared to depend on cotyledonary photosynthesis. Once stored reserves have been used, cotyledon photosynthesis is of major importance to early seedling growth. Covering the cotyledon resulted in: (1) a greater proportion of accumulated dry matter being transported to leaves and stems at the expense of root growth; (2) a significant decrease in specific leaf weight of first leaves; and (3) a reduction in seedling growth of 36% at 18 days of age. Cotyledons provided all of the photosynthate when seedlings were 7 days old. A subsequent decrease in photosynthetic contribution of cotyledons was in proportion to the decrease in cotyledon area as a percentage of total photosynthetic area and was only 18% by the time seedlings were 19 days old.