I understand that very well, thats why I wrote, we got 3n sporophytic stage. Saying sporophytic offcourse means a 2N stage only. We crossed a normal radish (2n = 18) with the polyploid 4n (2n = 36) radish, getting few 3n (2n = 27) (sporophyte) radish seeds. Pankaj
On Sat, Sep 25, 2010 at 11:45 PM, Gurcharan Singh <[email protected]> wrote: > Pankaj ji > You are again confusing between N and X, that was my original correction > that you did not realize. > A plant can either be N (gametic) or 2N (sporophytic), it can't be 2N, 4N, > 6N, etc. > it can be 2N=2X, 3X, 4X, 6X, 8X, etc., all except first one being polyploids > > -- > Dr. Gurcharan Singh > Retired Associate Professor > SGTB Khalsa College, University of Delhi, Delhi-110007 > Res: 932 Anand Kunj, Vikas Puri, New Delhi-110018. > Phone: 011-25518297 Mob: 9810359089 > http://people.du.ac.in/~singhg45/ > > On Sat, Sep 25, 2010 at 11:09 AM, Pankaj Kumar <[email protected]> > wrote: >> >> I have done experiments personally and they are not always sterile. I >> had crossed 2n and 4n Raddish and got 3n sporophytic stage. >> Thanks anyways. >> Pankaj >> >> >> On Sat, Sep 25, 2010 at 11:29 PM, Gurcharan Singh <[email protected]> >> wrote: >> > A plant with 3X in gametic stage, would become hexaploid sporophytic >> > phase >> > 2N=3X may generally result from a cross between a diploid and a >> > tetraploid, >> > and would be sterile and perish soon, unless it multiplies vegetatively, >> > or >> > else duplication of chromosomes occurs to make it hexaploid, a >> > phenomenon >> > commonly seen in Senecio and Tragopogon. >> > >> > -- >> > Dr. Gurcharan Singh >> > Retired Associate Professor >> > SGTB Khalsa College, University of Delhi, Delhi-110007 >> > Res: 932 Anand Kunj, Vikas Puri, New Delhi-110018. >> > Phone: 011-25518297 Mob: 9810359089 >> > http://people.du.ac.in/~singhg45/ >> > >> > On Sat, Sep 25, 2010 at 10:51 AM, Pankaj Kumar <[email protected]> >> > wrote: >> >> >> >> I imagine if it was a correction of addition. Anyways, just a >> >> querry...So you mean to say a plant with 3x chromosome is not a >> >> polyploid? >> >> Pankaj >> >> >> >> On Sat, Sep 25, 2010 at 9:30 PM, Gurcharan Singh <[email protected]> >> >> wrote: >> >> > Pankaj ji >> >> > A slight correction. Every plant has N (gametic) and 2N (sporophytic) >> >> > chromosomes. Every plant has basic number X, usually same for a >> >> > genus. A >> >> > diploid would have 2N=2X, whereas a polyploid would have 2N=4X >> >> > (tetraploid), >> >> > 6X (hexaploid), 8X (octaploid), etc. Plant is known as polyploid and >> >> > phenomenon as polyploidy. >> >> > -- >> >> > Dr. Gurcharan Singh >> >> > Retired Associate Professor >> >> > SGTB Khalsa College, University of Delhi, Delhi-110007 >> >> > Res: 932 Anand Kunj, Vikas Puri, New Delhi-110018. >> >> > Phone: 011-25518297 Mob: 9810359089 >> >> > http://people.du.ac.in/~singhg45/ >> >> > >> >> > >> >> > On Sat, Sep 25, 2010 at 6:59 AM, Pankaj Kumar >> >> > <[email protected]> >> >> > wrote: >> >> >> >> >> >> Usually the chromosoe number is 2n or diploid, when an organism has >> >> >> more than two sets of chromosomes then they are called polyploid and >> >> >> the phenomena is called Polyploidy. >> >> >> It is not a very uncommon phenomena in plants. Highest polyploidy is >> >> >> found in ferns. Orchidaceae is supposed to be one group with high >> >> >> polyploidy too. >> >> >> Regards >> >> >> Pankaj >> >> >> >> >> >> >> >> >> >> >> >> On Sat, Sep 25, 2010 at 7:17 PM, promila chaturvedi >> >> >> <[email protected]> wrote: >> >> >> > Dear All, >> >> >> > I want to know what is Polyploid and Polyploidy. This is >> >> >> > usuall occurance in >> >> >> > Passifloras, but can bein other plants as well. >> >> >> > Promia >> >> >> >> >> >> >> >> >> >> >> >> -- >> >> >> *********************************************** >> >> >> "TAXONOMISTS GETTING EXTINCT AND SPECIES DATA DEFICIENT !!" >> >> >> >> >> >> >> >> >> Pankaj Kumar Ph.D. (Orchidaceae) >> >> >> Research Associate >> >> >> Greater Kailash Sacred Landscape Project >> >> >> Department of Habitat Ecology >> >> >> Wildlife Institute of India >> >> >> Post Box # 18 >> >> >> Dehradun - 248001, India >> >> > >> >> > >> >> > >> >> > >> >> > >> >> >> >> >> >> >> >> -- >> >> *********************************************** >> >> "TAXONOMISTS GETTING EXTINCT AND SPECIES DATA DEFICIENT !!" >> >> >> >> >> >> Pankaj Kumar Ph.D. (Orchidaceae) >> >> Research Associate >> >> Greater Kailash Sacred Landscape Project >> >> Department of Habitat Ecology >> >> Wildlife Institute of India >> >> Post Box # 18 >> >> Dehradun - 248001, India >> > >> > >> > >> > >> > >> >> >> >> -- >> *********************************************** >> "TAXONOMISTS GETTING EXTINCT AND SPECIES DATA DEFICIENT !!" >> >> >> Pankaj Kumar Ph.D. (Orchidaceae) >> Research Associate >> Greater Kailash Sacred Landscape Project >> Department of Habitat Ecology >> Wildlife Institute of India >> Post Box # 18 >> Dehradun - 248001, India > > > > -- > Dr. Gurcharan Singh > Retired Associate Professor > SGTB Khalsa College, University of Delhi, Delhi-110007 > Res: 932 Anand Kunj, Vikas Puri, New Delhi-110018. > Phone: 011-25518297 Mob: 9810359089 > http://people.du.ac.in/~singhg45/ > > -- *********************************************** "TAXONOMISTS GETTING EXTINCT AND SPECIES DATA DEFICIENT !!" Pankaj Kumar Ph.D. (Orchidaceae) Research Associate Greater Kailash Sacred Landscape Project Department of Habitat Ecology Wildlife Institute of India Post Box # 18 Dehradun - 248001, India
