Heterosis

Cloning and functional prediction of differentially expressed genes in the leaves of Glycine max parents and hybrids at the seedling stage

J. Zhang, Yao, D., Wang, P., Guan, S. Y., Ma, J., and Fu, Y. P., Cloning and functional prediction of differentially expressed genes in the leaves of Glycine max parents and hybrids at the seedling stage, vol. 13, pp. 5474-5483, 2014.

Here, we compare the molecular mechanism of soybean heterosis through the differential expression of basic cloning. Specifically, we cloned 22 differentially expressed cDNA fragments from hybrid combinations of Jilin 38 x EXP (which had obvious yield advantages) and their parents. In addition, we compared the homology of these fragments and predicted their functions.

Analysis of DNA methylation patterns and levels in maize hybrids and their parents

T. J. Liu, Sun, L. F., Shan, X. H., Wu, Y., Su, S. Z., Li, S. P., Liu, H. K., Han, J. Y., and Yuan, Y. P., Analysis of DNA methylation patterns and levels in maize hybrids and their parents, vol. 13, pp. 8458-8468, 2014.

Heterosis is the superior performance of heterozygous individuals and has been widely exploited in plant breeding, although the underlying regulatory mechanisms still remain largely elusive. To understand the molecular basis of heterosis in maize, in this study, roots and leaves at the seedling stage and embryos and endosperm tissues 15 days after fertilization of 2 elite hybrids and their parental lines were used to estimate the levels and patterns of cytosine methylation by the methylation-sensitive amplification polymorphism method.

Genetic diversity of different populations and improved growth in the F1 hybrids in the swimming crab (Portunus trituberculatus)

B. Q. Gao, Liu, P., Li, J., Wang, Q. Y., and Li, X. P., Genetic diversity of different populations and improved growth in the F1 hybrids in the swimming crab (Portunus trituberculatus), vol. 13, pp. 10454-10463, 2014.

The swimming crab, Portunus trituberculatus, is widely distributed throughout the coastal waters of Asian-Pacific nations and is an important economic species in this region. The aquaculture of swimming crabs has been plagued by problems associated with low growth rates, poor flesh quality, and weak disease resistance. To overcome these problems, selective breeding programs have been suggested as a means of genetically improving these traits in stock populations.

Molecular cloning and functional analysis of MRLC2 in Tianfu, Boer, and Chengdu Ma goats

H. G. Xu, Xu, G. Y., Wan, L., and Ma, J., Molecular cloning and functional analysis of MRLC2 in Tianfu, Boer, and Chengdu Ma goats, vol. 12, pp. 3510-3520, 2013.

To determine the molecular basis of heterosis in goats, fluorescence quantitative polymerase chain reaction (PCR) was performed to investigate myosin-regulatory light chain 2 (MRLC2) gene expression in the longissimus dorsi muscle tissues of the Tianfu goat and its parents, the Boer and Chengdu Ma goats. The goat MRLC2 gene was differentially expressed in the crossbreed, and the purebred mRNA were isolated and identified using fluorescence quantitative reverse transcription-PCR (RT-PCR).

Genetic analysis of NaCl tolerance in tomato

A. Saeed, Shahid, M. Q., Anjum, S. A., Khan, A. A., Shakeel, A., Saleem, M. F., and Saeed, N., Genetic analysis of NaCl tolerance in tomato, vol. 10, pp. 1754-1776, 2011.

We attempted to find the suitable parents for the development of tomato hybrids for high salt soils by exploiting combining ability, gene action and heterosis. Six salt-tolerant and three salt-intolerant genotypes, along with their 18 F1 crosses, were evaluated at seedling stage under 10 and 15 dS/m (NaCl) salinity stress, compared to the control level of salinity.

Non-additive genetic effects on weights and performance of a Brazilian Bos taurus x Bos indicus beef composite

G. B. Mourão, Ferraz, J. B. S., Eler, J. P., Bueno, R. S., Balieiro, J. C. C., Mattos, E. C., and Figueiredo, L. G. G., Non-additive genetic effects on weights and performance of a Brazilian Bos taurus x Bos indicus beef composite, vol. 7, pp. 1156-1163, 2008.

The aim of the present study was to evaluate the heterosis effects on weaning weight at 205 days (WW, n = 146,464), yearling weight at 390 days (YW, n = 69,315) and weight gain from weaning to yearling (WG, n = 59,307) in composite beef cattle. The fixed models were: RM, which included contemporary groups, class of age of dam, outcrossing percentages for direct and maternal effects, and additive direct and maternal (AM) breed effects; R, RM model, minus AM breed effects, and H, RM model, minus additive breed effects. The estimates for W205 were in general positive (P 0.01).

Genetic parameters in parents and hybrids of circulant diallel in popcorn

R. M. Rangel, Júnior, A. T. Amaral, Scapim, C. A., Júnior, S. P. Freitas, and Pereira, M. G., Genetic parameters in parents and hybrids of circulant diallel in popcorn, vol. 7, pp. 1020-1030, 2008.

With the aim of estimating genetic parameters and identifying superior popcorn combinations, 10 parents were crossed in a circulant diallel and evaluated together with the 15 resulting hybrids at two locations in two growing seasons for grain yield, number of broken plants, number of partially husked ears and popping expansion. The hybrids were less sensitive to environmental variations than the parents of the diallel in the 2003/2004 and 2004/2005 growing seasons. The genetic parameters suggested possible genetic gains for grain yield and popping expansion, mainly.

Genetic distances between popcorn populations based on molecular markers and correlations with heterosis estimates made by diallel analysis of hybrids

R. E. F. Munhoz, Prioli, A. J., Júnior, A. T. Amaral, Scapim, C. A., and Simon, G. A., Genetic distances between popcorn populations based on molecular markers and correlations with heterosis estimates made by diallel analysis of hybrids, vol. 8, pp. 951-962, 2009.

Diallel analysis was used to obtain information on com­bining ability, heterosis, estimates of genetic distances by random amplified polymorphic DNA (RAPD) and on their correlations with heterosis, for the popcorn varieties RS 20, UNB2, CMS 43, CMS 42, Zélia, UEM J1, UEM M2, Beija-Flor, and Viçosa, which were crossed to obtain all possible combinations, without reciprocals. The genitors and the 36 F1 hybrids were evaluated in field trials in Maringá during two growing seasons in a randomized complete block design with three replications.

Apomixis and cassava

N. M. A. Nassar, Apomixis and cassava, vol. 1, pp. 147-152, 2002.

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 Manihot glaziovii and M. neusana.

Subscribe to Heterosis