A sequence tagged site (STS) marker encoding Copia-like retrotransposable element is associated with male specific sex expression in Momordica dioica Roxb.

2016 ◽  
Vol 201 ◽  
pp. 265-270 ◽  
Author(s):  
Jatindra Nath Mohanty ◽  
Sanghamitra Nayak ◽  
Sumita Jha ◽  
Raj Kumar Joshi
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sujatha Thankeswaran Parvathy ◽  
Amala Joseph Prabakaran ◽  
Thadakamalla Jayakrishna

AbstractCastor (Ricinus communis L) is an ideal model species for sex mechanism studies in monoecious angiosperms, due to wide variations in sex expression. Sex reversion to monoecy in pistillate lines, along with labile sex expression, negatively influences hybrid seed purity. The study focuses on understanding the mechanisms of unisexual flower development, sex reversions and sex variations in castor, using various genotypes with distinct sex expression pattern. Male and female flowers had 8 and 12 developmental stages respectively, were morphologically similar till stage 4, with an intermediate bisexual state and were intermediate between type 1 and type 2 flowers. Pistil abortion was earlier than stamen inhibition. Sex alterations occurred at floral and inflorescence level. While sex-reversion was unidirectional towards maleness via bisexual stage, at high day temperatures (Tmax > 38 °C), femaleness was restored with subsequent drop in temperatures. Temperature existing for 2–3 weeks during floral meristem development, influences sexuality of the flower. We report for first time that unisexuality is preceded by bisexuality in castor flowers which alters with genotype and temperature, and sex reversions as well as high sexual polymorphisms in castor are due to alterations in floral developmental pathways. Differentially expressed (male-abundant or male-specific) genes Short chain dehydrogenase reductase 2a (SDR) and WUSCHEL are possibly involved in sex determination of castor.


2014 ◽  
Vol 176 ◽  
pp. 85-90 ◽  
Author(s):  
Biplab Kumar Bhowmick ◽  
Satyabrata Nanda ◽  
Sanghamitra Nayak ◽  
Sumita Jha ◽  
Raj Kumar Joshi

2002 ◽  
Vol 127 (4) ◽  
pp. 673-676 ◽  
Author(s):  
Genet Teshome Mekuria ◽  
Margaret Sedgley ◽  
Graham Collins ◽  
Shimon Lavee

A sequence-tagged site (STS) was developed to identify a genetic marker linked to resistance to olive leaf spot caused by the pathogen, Spilocea oleaginea (Cast) (syn. Cycloconium oleaginum Cast.). The STS was based on a randomly amplified polymorphic DNA (RAPD) marker of about 780 base pairs (bp) linked to olive leaf spot resistance. Several primer pairs were developed to flank the sequence, and one pair produced the expected polymorphism between resistant and susceptible individuals tested, and was used as an STS marker. This primer pair was tested against parents and 34 individuals from a population segregating for resistance to olive leaf spot, and 12 commercial olive (Olea europaea L.) cultivars showing various levels of resistance to the disease. The STS marker was present in 71.4% of the parents and progeny that were designated as resistant, and was absent in 87% of the parents and progeny showing susceptibility. These primers were also able to distinguish cultivars such as `Koroneiki' and `Leccino', that are reported to show resistance to olive leaf spot, from `Barouni' and `Mission', that are reported to be susceptible. This is the first report of a STS marker for olive, and its use will assist greatly in screening olive progeny for resistance to leaf spot in breeding programs.


Euphytica ◽  
2013 ◽  
Vol 197 (1) ◽  
pp. 39-46 ◽  
Author(s):  
Akira Kanno ◽  
Shosei Kubota ◽  
Katsuya Ishino

2007 ◽  
Vol 97 (2) ◽  
pp. 162-169 ◽  
Author(s):  
S. H. Lee ◽  
S. M. Neate

Five random amplified polymorphic DNA markers, two in coupling (OPAH5545C, and OPBA12314C) and three in repulsion phase (UBC285158R, OPC2441R, and OPB17451R), closely linked to Rsp genes conferring resistance to Septoria speckled leaf blotch (SSLB), were identified using bulked segregant analysis in three F2 populations, each containing a Rsp gene. These markers were converted into the sequence tagged site (STS) markers SUBC285, SOPC2, SOPAH5, and SOPBA12. Another STS marker (MWG938) linked to Rsp2 in coupling phase was also identified in an F2 population from the cross Robust/CIho 4780. The STS markers were tested on a set of 42 resistant and susceptible barley germplasm lines and 98 landraces. The expected sizes of marker fragments associated with each allele at Rsp loci were present in resistant or susceptible accessions. Efficiency of marker-assisted selection (MAS) for Rsp1, Rsp2, and Rsp3 using STS markers were evaluated in three F2–3 populations in the greenhouse and the field. Results of testing F2–3 progeny demonstrated that the accuracy of MAS was, with one exception, greater than 97% in the greenhouse and in two field locations (90% in the Osnabrock, ND trial for Rsp2). The STS markers closely linked to Rsp genes also identified the SSLB resistance corresponding to Rsp1, Rsp2, or Rsp3 in gene pyramiding F2 populations. The STS markers tightly linked to Rsp genes may be useful for M and for pyramiding with other genes in barley breeding for SSLB resistance.


Agronomie ◽  
1983 ◽  
Vol 3 (3) ◽  
pp. 233-238 ◽  
Author(s):  
K. RAJASEKARAN ◽  
M. G. MULLINS
Keyword(s):  

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