Question

The presence of many embryos (polyembryony) is a characteristic feature of
(a) Citrus
(b) Mango
(c) Banana
(d) None of the above

Answer 1

Hint: Polyembryony generally occurs at the time of seed development which leads to the formation of more than one embryo from a single seed. Polyembryony also takes place by fertilization of more than one oosphere and adventive budding.

Complete Answer:
The presence of more than one embryo is a characteristic feature of citrus. Polyembryony in citrus was first discovered by Leeuwenhoek in 1719. In citrus polyembryony takes place in ovules where more than one egg cell gets fertilized, this happens due to the presence of more than one egg cell in the embryo sac or due to the presence of more than one embryo sac.

Additional information:
Polyembryony is of three different types: simple, cleavage, and adventive.
Citrus shows simple polyembryony whereas cleavage polyembryony takes place in pinus and orchids where polyembryony gets divided into two or more parts and in case of adventive polyembryony formation of additional embryo take place from different part of ovule except the egg. Adventive polyembryony takes place in citrus, opuntia, onion, and groundnut.
Apomixis is the process of forming an embryo by an asexual method where seed formation takes place without the fusion of gamete. Nowadays production of plant seed by apomictic polyembryony process become very useful for the farmer because for high crop production farmers use hybrid varieties but from generation to generation the crop production gets affected due to unmaintained hybrid vigour which needs the development of new seed every year. Development of new hybrid seeds is a very costly process that's why agriculture scientists used apomictic processes for the generation of numbers of seeds. In apomixis segregation of character does not take place and hybrid vigour gets maintained from generation to generation.

So, the correct answer is ‘Citrus’.

Note: Polyembryony increases the potential of the crop to tolerate varied conditions; it also helps to maintain hybrid vigour but in some cases, polyembryony hampers the formation of the zygotic embryo which affects the hybridization of plants.