Cytological mechanisms of 2n pollen formation in the wild potato Solanum okadae and pollen-pistil relations with the cultivated potato, Solanum tuberosum

Tetraploid potato hybrids representing three genomic compositions (TTTT, TTPP, and TTPC (T, Solanum tuberosum; P, Solanum phureja; C, Solanum chacoense)) were constructed by crossing S. tuberosum (2n = 4x = 48) cultivars or advanced breeding selections among themselves or with 2n pollen producing selections of either S. phureja (2n = 2x = 24) or F1 hybrids between S. phureja and S. chacoense (2n = 2x = 24). Seedling families were evaluated in the fall season and selections within each family were evaluated in spring trials at Ait-Melloul, Morocco. Genomic composition was the greatest source of variance for yield-attributing traits, with TTPC outperforming other hybrids in fall trials for vine vigor, tuber set, and tuber yield and TTPP outperforming other hybrids in spring trials for the same traits. The results imply that analytic breeding for potato by construction of complex interspecific hybrids may result in clones surpassing a previously proposed heterotic threshold if the target environment is conducive to expression of favorable traits from alien germ plasm.Key words: Solanum phureja, Solanum chacoense, Solanum tuberosum, 4x–2x hybrids, potato, analytic breeding.

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CYTOLOGY OF 2n POLLEN FORMATION IN DIPLOID ALFALFA, MEDICAGO SATIVA

Canadian Journal of Genetics and Cytology ◽

10.1139/g79-057 ◽

1979 ◽

Vol 21 (4) ◽

pp. 525-530 ◽

Cited By ~ 52

Author(s):

Nicholi Vorsa ◽

E. T. Bingham

Keyword(s):

Medicago Sativa ◽

Seed Set ◽

Pollen Grains ◽

Genetic Constitution ◽

2N Pollen ◽

Diploid Parent ◽

2N Gamete ◽

Medicago Sativa L ◽

Pollen Formation ◽

Mother Cells

Four diploid (2x) clones of alfalfa, Medicago sativa L., which produced good seed set when used as male parents in 4x-2x crosses were selected for study. The 2x clones descended from 2x haploids of cultivated 4x alfalfa. Fertility in the 4x-2x cross was due to the production of pollen with the unreduced chromosome number (2n pollen) from the 2x parent. The cytological mechanism of 2n pollen formation was found to be disorientation of spindles at metaphase II in up to 38% of the pollen mother cells. Thus, both n and 2n pollen were produced by all four diploids examined. Normal spindles at metaphase II were oriented such that they defined the poles of a tetrahedron and resulted in normal tetrads in a tetrahedral arrangement. Disoriented spindles were basically parallel to each other and resulted in formation of dyads and occasionally a triad. Dyads developed into two 2n pollen grains; triads developed into one 2n and two n pollen grains. Since both n and 2n pollen grains are produced by the diploids, they can be maintained as diploids or they can be used as male parents in crosses to tetraploids. The genetic constitution of 2n pollen resulting from parallel spindles is similar to that expected after first division restitution of meiosis and much of the heterozygosity of the diploid parent is conserved in the gametes. The 2n gamete mechanism has potential application in germplasm transfer and in maximizing heterozygosity in tetraploid hybrids.

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An AFLP Marker Core Subset for the Cultivated Potato Species Solanum phureja ( Solanum tuberosum L. subsp. andigenum)

American Journal of Potato Research ◽

10.1007/s12230-021-09849-w ◽

2021 ◽

Author(s):

Alfonso del Rio ◽

John Bamberg

Keyword(s):

Solanum Tuberosum ◽

Aflp Marker ◽

Solanum Tuberosum L ◽

Solanum Phureja ◽

Cultivated Potato ◽

Potato Species ◽

Core Subset

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Meiotic Aberrations Underlying Pollen Sterility in Cultivated Potato (Solanum tuberosum L.)

CYTOLOGIA ◽

10.1508/cytologia.81.271 ◽

2016 ◽

Vol 81 (3) ◽

pp. 271-274

Author(s):

Tanuja Buckseth ◽

Manjit Inder Singh Saggoo

Keyword(s):

Solanum Tuberosum ◽

Pollen Sterility ◽

Cultivated Potato ◽

Meiotic Aberrations

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Recognition of Phytophthora infestans in potato (Solanum tuberosum L.): Scr74 gene as an example

Open Agriculture ◽

10.1515/opag-2016-0021 ◽

2016 ◽

Vol 1 (1) ◽

Author(s):

Mulusew Kassa Bitew ◽

Emmanouil Domazakis

Keyword(s):

Amino Acid ◽

Phytophthora Infestans ◽

Solanum Tuberosum L ◽

Effector Proteins ◽

Wild Potato ◽

Detached Leaf ◽

Polymorphic Genes ◽

Cysteine Rich Protein ◽

In The Wild ◽

Polymorphic Gene

AbstractPhytophthora infestans is the causal agent of late blight, the most devastating disease of potato worldwide. The P. infestans genome encodes potentially polymorphic genes that evolve continually to evade the recognition of plant R genes, though it has hundreds of predicted and conserved effector proteins recognised by the plant. The gene Scr74 encodes a predicted 74-amino acid secreted cysteine-rich protein belonging to a highly polymorphic gene family within P. infestans. This study screened the recognition of Scr74 genes in wild potato genotypes from August 2013 to January 2014 in the Plant Breeding Laboratory of Wageningen University, the Netherlands. To identify the recognition of the Scr74 gene, we grew potato genotypes in the green house for PVX assays, detached leaf assays and molecular work. Twenty-seven good-quality sequences of the Scr74 gene variant with a length of 74 amino acids were found and more frequent amino acid variation was detected on the mature protein. Seventeen Scr74 constructs were identified as diversified and two effectors were strongly recognised by wild S. verrucosum genotypes via effectoromics from the PVX assay. A strong plant cell death hypersensitive response (HR) was recorded on wild S. verrucosum and S. tuberosum genotypes from the detached leaf assay. This recognition seems to be a useful indicator for the presence of a resistance gene (s) to the polymorphic effectors of P. infestans (as it has seen on Scr74 gene) in the wild potato genotypes.

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