The process of appearance of recombination nodules occurs at which sub stage of prophase I in meiosis?

Recombination nodules appear during the pachytene stage of prophase I in meiosis. At this stage, the homologous chromosomes are paired and crossing over occurs between them, resulting in the exchange of
genetic material. 
(1) Diakinesis is the fi nal stage of meiotic prophase I. This is marked by terminalisation of chiasmata.
(2) The second stage of prophase I is called zygotene. During this stage, chromosomes start pairing together,
and this process of association is called synapsis.
(4) Diplotene is characterised by the appearance of chiasmata.