** 我非此領域專家，對植物幾乎不懂，自己摸索學習，引用參考請小心!**
我的看法:(自己研判，不一定正確，有誤請告知)
1.九重葛屬異花授粉及自交不親合
2.三個基本園藝種(光葉/毛葉/秘魯)每一種內之栽培種，有部份屬可育，部份不可育，主要受地區氣候環境影響
3.所有種"間"雜交種應屬不可育，然於某特殊情況下(如二倍變四倍體，可能自然或人為促變)仍可能變為可育
4. 種"內"各栽培品種有因地區環境、自然或人工變異(芽變)而產生些微基因差異，然根本上仍屬同"種"，其中可育栽培品種間的雜交，當然包括如Formosa與Mrs. Eva組合及Mrs. Eva品系內綠葉栽培種與金邊或銀邊斑葉品種間之雜交組合，兩者之組合均屬種"內"雜交，其原可育雜交後之後代仍屬同種，亦應屬可育。
5.任何不可育品種如經多倍體變異，不管是同源或異源，雖有可能恢復其可育性(異源高於同源)，但實務上並非一定如此，沒那麼簡單!!!
6. 紅花品種少有結籽，然偶有花友採獲種子，我認為三基本種(Species)中的毛葉種(spectabilis)有玫瑰花色品種，秘魯種也有紅色(暗洋紅至粉)，猜想應屬這兩種其中之品種可能性較高，秘魯種的品種非常少，但卻有二種間雜交種，因此推段其可結籽性高，屬雜交種(如Butt.)多倍體變異品種則可能性較低
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雜交種(hybrid)，分類學上稱為雜交分類群(nothotaxon)，雜交分類群包括雜交屬(nothogenus)、雜交種(nothospecies)、與雜交型(nothomorph)，即農學界一般稱的: 屬間雜交、種間雜交及種內雜交
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九重葛：
紫茉莉Nyctaginaceae科(Family)，九重葛Bougainvillea屬(Genus)，種(Species)有十幾種原種，惟常見者只有:光葉(Glabra)/毛葉(Spectabilis)/秘魯(Peruviana)及其雜交種(如光葉與秘魯B.x buttiana，毛葉與秘魯B.x spectoperuviana，毛葉與光葉B.x spectoglabra)，種內各有許多栽培品種(Cultivar)，目前已知只有極少數栽培品種可結籽。
光葉種內栽培品種如Formosa及Mrs.Eva品系具結籽能力，Mrs.Eva品系經芽變出有十幾種栽培品種(如金邊銀邊)
很想知道"種間"與"種內"雜交的相關知識**
1.如將Formosa與Mrs.Eva品系任一品種兩者雜交，是否就是"種內"雜交? 如是
2.那Mrs.Eva品系內小葉白與金邊銀邊的雜交應叫甚麼? 也是"種內"雜交? 或不是?
3.種間(如B.x buttiana，B.x spectoperuviana， B.x spectoglabra)是否全是不可育(不結籽)?
4. 只有種內(如Formosa與Mrs.Eva)雜交具可育性(結籽)? 如是，那代表毛葉及秘魯之種內一定也有可育品種?
5.種內(如Formosa與Mrs.Eva)雜交的第2代3代...仍具可育性?
...
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九重葛有性繁殖必須先澄清
1. 自花授粉或是異花授粉?
2.自交相容或不相容?
維基百科，自由的百科全書
http://zh.wikipedia.org/wiki/%E9%9B%9C%E4%BA%A4%E7%A8%AE
雜交（英語：hybrid，又稱雜種或混種）是一個涉及有性繁殖過程，是指二倍體或多倍體染色體在減數分裂後，與另一組分裂後的同源染色體重新配對，形成新的染色體稱為雜交種，一般可以含有以下含義：[1]：
雜交種，是指從兩種不同的動物或植物雜交產生的物種的新物種，分二類情況：
- 第一類：同一種內的不同亞種間相互交配產生的後代，也被稱為種內雜交；進一步的有在同一屬下的不同種之間的互相交配產生的後代，稱為種間雜交（interspecific hybridization）；
- 第二類：指不同族群（population）之間相互交配產生的後代，並形成一個單一物種。最常見的是植物的花粉傳播和對動物進行育種。植物雜交並形成雜交種在自然界很常見，因為植物並不能注意和選擇交配對象，而這在動物中非常罕見，除非它們沒有意識到對方與自己是不同族群。
一般地，動物頻繁雜交並培育出穩定的雜交種（譬如騾子和狗)，往往是在被強行干預之下才可能發生。不同種的動物通過雜交產生雜交種是非常困難的，失敗率很高，而且通常雜交子代不具生育能力。若要培養一個具有繁殖能力的全新雜交種，則需要許多代不斷地反覆雜交嘗試才可能成功。期間對子代的人工選擇和淘汰是必須的，也意味著嚴格的封閉管理。
**待續...
wow, Larry, you have opened up a very interesting topic.I feel motivated to comment on this topic with the knowledge I have (not necessary all correct because I am too, still learning) and hope to share a point or two with you.
Both Formosa and Mrs Eva are in the germplasm collection at NBRI, indicating they have values in breeding programme.
On your queries of 1 & 2, if they ever set seeds, you can safely call it "種內"雜交 .
Natural seeds occurrence does happen. Several cultivars for B glabra and B spectabilis set seeds occasionally under the right climate and the right age of the plant. Tetra Mrs McClean is known to set seeds at Lucknow India too. In Malaysia around April/May we can strike better luck finding natural seeds from B. glabra. Speciosa from B spectabilis is also an often seed bearer.
On no 3, these are interspecific hybrids and mostly (or you call safely say all) are triploids. Thus, they are sterile.
However, there are still tetraploid hybrids around in these interspecific hybrids ( B x spectoperuviana 'Shubhra' and Bx buttiana 'Tetra Mrs McClean' to name a few) and therefore given the correct natural condition, although very unlikely and near mission impossible, they technically can set seed if crossed.
So the other interesting point to note on your queries for 1,2 and 3 is which plant is the pollen plant. Apart from seed sterility, we also have the problem of pollen sterility. If we crossed a fertile seeder with a sterile pollinator, we still don't get result because nothing will be viable.
For no 4 & 5, same species offspring from fertile plant doesn't guarantee future fertility. Many modern cultivars are actually triploids (2n=3x=51), because many only pollenized the induced tetraploidy (seed bearer) cultivar, while still retain the pollinator diploids condition. Unless we ensure pairing of chromosome during meiosis will yield fertile tetraploids (2n=4x=68), the offspring we get can safely regard all offspring sterile.
Tetraploids are self incompatible but will happily set seeds crossing with other fertile forms. Therefore, we need to ensure both plants are fertile, a cultivar with ability to produce seeds and a plant with fertile pollen. Seedling doesn't come true to the form and types and therefore they should be used for evolving new cultivars.
Many new evolved cultivars from bud sport has imperfect floral tubes (Mahsuri and Ratana to name a few) and breeding almost impossible. Omvrey bred Mrs Eva Icecream with induced tetraploidy of both seeder and pollinator through colchicine with the help of the Agricultural Dept of Malaysia (strangely, the rubber plant development dept which is the only helpful dept around that time).
We had been collecting and planting many natural seeds but later eliminated all because they didn't rise up to meet any aesthetic requirement and agriculturally vigorous and growing them will be a waste of time. They were often flowering with paler bracts, less flowering habit and long sharp thorns with tall and wild growth condition.
Only a PLANNED hybridization programme will give us good cultivar, which has vigorous and highly floriferous plants.
What the modern world now lacking for bougainvillea is a complete germplasm study, which understood is impossible. But NBRI has done an amazing amount of work and I trust they are continuing with this.
[版主回覆11/27/2012 11:53:34]
It’s actually not an easy work on this topic. There were queries bothered me. Just no one can consult. I’ve felt feadache for some days. Howere, yesterday was a good day, ‘cause I finally connected pieces of inforamtion and though out some idea that might be the answers I needed. And this morning was also a happy moment, because I found most of my idea or conclusion was so close to yours. So appreciate and thank to you.
"Mrs Eva Icecream with induced tetraploidy of both seeder and pollinator" is a good news for my friend Mr. Yang(二羊), he has high interest on bougainvillea seed breeding.
I'd like to thaink you again for such a helpfull reply on this topic. See you!
pollinator is a wrong words to use here. Pollinator is the agent goes round carrying the pollen from the anther to the stigma, i.e insect such as bee. What I really want to say is the plant being the pollen provider and I've forgotten the botanical term for it.
[版主回覆11/29/2012 06:41:21]I see! thks!
http://bbs.mychg.org/forum.php?mod=viewthread&tid=113158&page=14#pid3486206
會結子的紅九重葛較接近mrs butt或四季紅?(不是我給你的根苗-古早紅)