Developmental and Structural Section
Al-khatib, Rami , Sundberg, Marshall D .
Anatomical Changes during Fruit Ripening in Two Lines of Tabasco Pepper (Capsicum frutescens).
Fruit development was examined in two lines of Tabasco pepper (Capsicum frutescens) which had previously been selected for hard-to-pick persistent fruit (HP) or easy-to-pick (EP) fruit. Four plants of each line were grown under glass. Random selections of ten flowers of each line were tagged at 3 or 4-day intervals until the first-tagged flowers were in the ?mature red? harvest condition. At that point all samples were collected and paraffin-processed for anatomical examination. Cells and intercellular spaces in the separation zone and fruit wall were examined morphometrically to determine what, if any, anatomical changes were associated with ease of fruit separation from the pedicle. Although cells in both the central and peripheral regions of the separation zone become sclerified in both lines, sclereid differentiation is faster and more complete in the HP line. The cells were larger in the central region than in the periphery of both lines and EP cells were larger than HP cells. Similarly in the fruit wall, EP cells tended to be larger than their HP counterparts in all areas and at all stages examined. During fruit growth and maturation significant differences in the volume of intercellular spaces also developed and by later stages, the cell walls of the EP line appeared to be thinning. These results suggest that a combination of larger cells, more intercellular spaces and enzymatic hydrolysis of the fruit cell walls all contribute to ease of fruit separation from the pedicle in the EP line.
1 - Emporia State University, Biological Sciences, Box 4050, 1200 Commercial Street, Emporia, Kansas, 66801, USA
Presentation Type: Paper
Location: Alpine A (Snowbird Center)
Date: Wednesday, August 4th, 2004
Time: 1:45 PM