Regulation of assimilation and senescence by the fruit in monocarpic plants

NOODÉN L.D.; GUIAMET J.J

PHYSIOLOGIA PLANTARUM

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 1989 vol. 77 p. 267 - 274

0031-9317

For most monocarpic species studied, blocking fruit development prevents or at least delays the death of the plants. However, it usually does not prevent the decline in photosynthetic rate, while it may or may not maintain the photosynthetic components (machinery) such as chlorophyll and ribulose 1,5-bisphosphate carboxylase. Since sink demand influences photosynthetic rate and the fruit-less plants have hmited sink capacity, their reduced photosynthesis may represent a metabolic adjustment but not senescence. The exact causes of the variable decreases in photosynthetic components in fruit-less plants are uncertain. The causes of metabolic decline may be different in reproductive-phase monocarpic plants with and without fruit. In any case, assimilation rate, i,e, photosynthesis, may not always provide a reliable index of senescence. Whether or not the developing fruits of monocarpic plants actually control the early and intermediate decline of metabolism is not clear; however, at least in soybean under non-stress conditions, they cause the final decrease and death