Molecular analysis of apomixis in cassava.
نویسندگان
چکیده
Cassava is the main staple for more than 800 million people in the tropics. It is propagated vegetatively by stem cuttings, which maintains superior genotypes but favors disease accumulation and spread. In this report, we present the results of the screening of the progeny and the second generation of the clone UnB 307 for apomixes using microsatellites. A total of 29 plants were screened, representing the maternal plant, its first and second generations that were left to open pollination. About 20% of the offspring were rated as genetically identical plants. This result confirms the facultative apomictic nature of cassava, with high environmental effect.
منابع مشابه
Apomixis and cassava.
Apomixis means seed formation without fertilization. In cassava (Manihot esculenta) it is an alternative to reproduction by cuttings, which normally transmits pathogens and leads to an accumulation of viral and bacterial diseases. Apomixis also assures preservation of heterosis and avoids genetic segregation. It occurs in wild relatives of cassava and has been transferred successfully from Mani...
متن کاملEmbryonic, Meiotic and Molecular Analysis of Apomictic Cassava (Manihot esculenta Crantz)
Apomixis genes have been successfully transferred to cassava by hybridizing it with the wild species, M. glaziovii. An interspecific hybrid of cassava and M. glaziovii was left for open pollination during three subsequent generations. Seven sibs and their maternal progenitor of the fourth generation were genotyped using five microsatellite loci previously developed for cassava. All sibs were id...
متن کاملCassava, Manihot esculenta Crantz, genetic resources: origin of the crop, its evolution and relationships with wild relatives.
About 98 species of Manihot are known. All of them are native to the New World and are concentrated in four regions in Brazil and Central America. All the Manihot species so far examined have 2n = 36 chromosomes. Interspecific hybrids between cassava and its wild relatives show relatively normal meiosis, and further generations can be obtained. Electrophoresis shows affinity among wild species ...
متن کاملThe nature of apomixis in cassava (Manihot esculentum, Crantz).
Apomixis in cassava is formed by aposporic embryo sacs which arise from cells in nucellus or from cells in the sexual embryo sac. There is an association between sterility and apomixis. It seems that sterility caused by defected meioses triggers a specific gene for exhibiting apomixis. This apomictic mechanism is favoured by natural selection since it offers an escape from lethality and provide...
متن کاملChromosome doubling induces apomixis in a cassava x Manihot anomala hybrid.
A new species was synthesized artificially by chromosome doubling of an interspecific hybrid between cassava and Manihot anomala. The ensuing polyploid type exhibits an apomictic nature and maintains its morphological characteristics in the progeny. It showed a 29% frequency of multiembryonic sacs in its examined ovules whereas the multiembryonic sacs were absent in the diploid type.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Genetics and molecular research : GMR
دوره 5 3 شماره
صفحات -
تاریخ انتشار 2006