在线观看亚洲精品专区-在线观看亚洲免费-在线观看亚洲免费视频-在线观看亚洲欧美-欧美freexxx-欧美free嫩交video

食品伙伴網服務號
 
 
當前位置: 首頁 » 專業英語 » 專業知識 » 正文

What are the reasons for producing transgenic plants instead of classical breedi

放大字體  縮小字體 發布日期:2007-06-06
核心提示:The classical way of plant breeding is a long process. It is mainly done by crossing two plants that are different but related. Pollen from one plant is transferred in a natural way by wind or by human help to another plant. In that way during meios

The classical way of plant breeding is a long process. It is mainly done by crossing two plants that are different but related. Pollen from one plant is transferred in a natural way by wind or by human help to another plant. In that way during meiosis the genes of both plants are distributed randomly to the progeny. By repeated backcrossing, a specific method in plant breeding, specific traits, such as resistances can also be introduced from a wild type into a cultivar.

Normally the offspring of crossing two plants is produced through a random process, because during meiosis (the production of gametes) the genes from both parents are distributed randomly to the gametes. For that reason, the product of the crossing process cannot be predicted. The process to select for the desired trait takes a long time, because from each crossing process a high number of progenies, which contain different characteristics and have to be selected for the desired traits, arise. So it can take a long time to get a new cultivar that shows the wanted traits, which means that it is also quite expensive to produce a new cultivar by classical breeding. Further classical breeding is limited, because crossing can only take place with more or less related species. If a resistance gene from an unrelated species has to be introduced into another crop, this is not possible.

Furthermore, genes from completely different organisms, for example, the Bt- toxin from bacteria can only be introduced into plants by genetic engineering.

更多翻譯詳細信息請點擊:http://www.trans1.cn
 
[ 網刊訂閱 ]  [ 專業英語搜索 ]  [ ]  [ 告訴好友 ]  [ 打印本文 ]  [ 關閉窗口 ] [ 返回頂部 ]
分享:

 

 
推薦圖文
推薦專業英語
點擊排行
 
 
Processed in 0.166 second(s), 17 queries, Memory 0.89 M
主站蜘蛛池模板: 国内精品久久久久影 | 久久久久大香线焦 | 性欧美黑人巨大videos | 女人张腿让男桶免费视频观看 | 日韩一级免费视频 | 亚洲福利视频一区二区 | 久久天天躁狠狠躁夜夜免费观看 | 澳门久久 | 日本三级吹潮 | 婷婷99视频精品全部在线观看 | 婷婷在线五月 | 国产精品怡红院永久免费 | 爱综合网| 色版视频| 午夜看片网站 | 欧美一级片免费在线观看 | 禁漫画羞羞动漫入口 | 天天操女人| 人成电影免费观看在线 | 中文字幕色婷婷在线精品中 | 18视频免费网址在线观看 | 天天色天天射天天操 | 国产毛片哪里有 | 天天夜干 | 四虎在线观看免费永久 | 97视频hd | 午夜视频在线网站 | 午夜影院在线观看免费 | 久久精品视频免费播放 | 久久精品免费观看视频 | 狠狠色狠狠色综合 | 中文字幕在线视频第一页 | 免费看啪啪的网站 | 国产免费私拍一区二区三区 | 日本不卡在线视频高清免费 | 日本69xxxxxxx69| 日韩一级精品视频在线观看 | 天天色操 | 国产欧美日韩综合精品一区二区 | 亚洲另类激情综合偷自拍 | 男女午夜特黄毛片免费 |