Aphids prepare their offspring for life by depositing them on a host plant. The aphids will also need symbiotic bacteria that are provided by the mother to the developing offspring. The symbiotic bacteria of the pea aphid are housed in special aphid “bacteriocyte cells. Some of the bacteriocytes are in close proximity to the ovaries where aphid offspring develop. During the formation of an aphid embryo*, a bacteriocyte will fuse with a special site on the embryo. The bacteria are transferred from the bacteriocyte to the developing embryo. Embryo nuclei that are destined to form bateriocytes mingle with the bacteria. When the cell membranes are produced, the bacteria will be housed in the a bacteriocyte cell with an aphid nucleus. As the aphid fully develops, it contains its own bacteriocytes with bacteria donated by its mother. This complex method ensures that aphids will have the bacteria they need to survive.
*TORU MIURA, CHRISTIAN BRAENDLE, ALEXANDER SHINGLETON, GEOFFROY SISK, SRINIVAS KAMBHAMPATI,and DAVID L. STERN. A Comparison of Parthenogenetic and SexualEmbryogenesis of the Pea Aphid Acyrthosiphonpisum. J Exp Zool B Mol Dev Evol. 2003 Feb 15;295(1):59-81.