Interspecific xenia and metaxenia in seeds and fruits of tomato

Abstract

Xenia, the transmission of traits from the pollinizer to the female's tissues, is a phenomenon hitherto unknown in tomatoes. Here, we describe xenia effects on the seeds and fruits of Solanum lycopersicum, the tomato, elicited by S. galapagense. The wild tomatoes, such as S. galapagense, have highly pilose fruit surface and minute seeds, unlike the domesticated species. Crossings between S. galapagense (pollinizer) and two large-seeded, glabrous cultivars of S. lycopersicum (females) tested the former's ability to raise the trichome density and trichome-to-1000-cell ratio and to reduce the seed weight in the latter's fruits. Selfed fruits of the two cultivars, Micro-Tom and Pusa Ruby, were compared to the crossed fruits. The pollen of S.galapagense was able to raise pilosity and to reduce seed weight in the crossed fruits of both cultivars, but with different magnitudes: seed reduction was more intense in Pusa Ruby, while pilosity increase was greater in Micro-Tom, both of which characterize xenia. Pilosity increase is not completely dependent on variation in epidermal cell density, which displayed no xenia effect.The difference between the maternal cultivars in the magnitude of pilosity increase may be due to the higher dilution of a putative male chemical signal (either hormone or RNA) in the larger fruits of Pusa Ruby. However, one cannot use the signal diffusion hypothesis to explain the xenia effects on seed weight.

Effects of Metaxenia on Stone Cell Formation in Pear (Pyrus bretschneideri) Based on Transcriptomic Analysis and Functional Characterization of the Lignin-Related Gene PbC4H2

“…There is a hypothesis that seeds in the fruit are heterozygous for the parental genotype. Metaxenia might alter the synthesis of hormones in heterozygous seeds, thereby affecting the levels of hormones secreted into the fruit and ultimately regulating the relevant metabolic processes [26,46]. Therefore, we speculate that the effect of metaxenia on lignin biosynthesis in pear fruit might be achieved by regulating hormone metabolism.…”

Efek xenia dan metaxenia pada persilangan tomat ranti dan tomat cherry

“…Penurunan jumlah biji juga dapat disebabkan oleh rendahnya jumlah ovul yang berhasil diserbuki oleh polen serta tingkat kompabilitas persilangan yang rendah. Penelitian oleh Piotto et al (2013) Zipori et al (2007) menyatakan bahwa persilangan dengan tetua yang berbeda dapat meningkatkan keragaman genetik yang luas. Menurut Syukur et al (2015), pemilihan tetua dalam program pemuliaan harus didasarkan pada keragaman genetik yang lebar agar dapat menghimpun alel yang berbeda.…”

“…Efek metaxenia dapat diamati langsung pada hasil persilangan serta memiliki ekspresi fenotipe yang berbeda pada persilangan. Piotto et al (2013) …”

Pengaruh Tetua Jantan terhadap Komponen Buah dan Biji Hasil Persilangan Enam Genotipe Kakao Mulia

“…(Mizrahi et al, 2004), mentimun (Olfati et al, 2010), durian (Indriyani et al, 2012), Arabidopsis thaliana (Andriotis et al, 2012), apel (Militaru, Butac, Sumedrea, & Chi, 2015), Brassica napus (Li et al, 2015), dan tomat (Piotto, Batagin-Piotto, de Almeida, & Oliveira, 2013;Rahaii et al, 2016). Pada persilangan lobak liar (Raphanus sativus), tetua betina berpengaruh terhadap perkembangan embrio, namun pengaruh tersebut sangatlah bergantung pada peran tetua jantan sebagai donor tepung sari dan peran tetua jantan tersebut dapat berubah-ubah setiap saat (Diggle et al, 2010).…”