How sex is determined in monoecious
plants. write their genes involved in it.
Answers
Answer:
Mechanisms underlying sex determination in plants are largely unknown. Silene latifolia is a dioecious species (with separate male and female individuals) which harbours XY sex chromosomes and constitutes an important model for sex determination in plants. Chromosome deletion experiments have shown that the Y chromosome of Silene latifolia carries two loci involved in sex determination: the first involved in the suppression of female organ development and the second involved in the activation of male organ development. Several attempts to identify the corresponding genes and the regulatory pathways controlled by these have been unsuccessful.
In the dioecious species Silene latifolia, four whorls of floral organs are observed in both male and female floral meristems, as it is the case for any hermaphrodite species: sepals, petals, stamens (male reproductive organs) and carpels (female reproductive organs). At an early stage, the flower meristem is similar in male and female plants (undifferentiated). As soon as all floral organ primordia are initiated, the female territory in the centre of the flower meristem is significantly smaller in male compared to female flower buds. Later, a filament develops in male flower, in place of female organs. In female flower buds, stamens are initiated but rapidly degenerate, whereas five fused carpels (female organs) develop in the centre. In this study, we investigated the possible mechanisms that may lead to female organ arrest in male flowers of S. latifolia.