{"id":775,"date":"2017-04-05T09:25:23","date_gmt":"2017-04-05T02:25:23","guid":{"rendered":"http:\/\/demo.prc.maiatech.com.vn\/?p=775"},"modified":"2017-04-05T09:25:23","modified_gmt":"2017-04-05T02:25:23","slug":"mat-mat-da-dang-di-truyen","status":"publish","type":"post","link":"https:\/\/prc.org.vn\/?p=775","title":{"rendered":"M\u1ea5t m\u00e1t \u0111a d\u1ea1ng di truy\u1ec1n"},"content":{"rendered":"\n\n\n\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Trong cu\u1ed9c s\u1ed1ng, s\u1ef1 tuy\u1ec7t ch\u1ee7ng lu\u00f4n lu\u00f4n \u0111\u1ed3ng h\u00e0nh v\u1edbi s\u1ef1 b\u1eaft \u0111\u1ea7u v\u00e0 h\u00ecnh th\u00e0nh c\u00e1c sinh v\u1eadt. Trong kho\u1ea3ng 600 tri\u1ec7u n\u0103m tr\u1edf l\u1ea1i \u0111\u00e2y, t\u1ed1c \u0111\u1ed9 tuy\u1ec7t ch\u1ee7ng v\u00e0o kho\u1ea3ng m\u1ed7i n\u0103m m\u1ed9t lo\u00e0i. \u0110\u1ebfn nay, t\u1ed1c \u0111\u1ed9 tuy\u1ec7t ch\u1ee7ng cao g\u1ea5p h\u00e0ng tr\u0103m, th\u1eadm ch\u00ed h\u00e0ng ng\u00e0n l\u1ea7n , nh\u01b0ng s\u1ef1 tuy\u1ec7t ch\u1ee7ng tr\u01b0\u1edbc \u0111\u00e2y l\u00e0 k\u1ebft qu\u1ea3 c\u1ee7a qu\u00e1 tr\u00ecnh ti\u1ebfn ho\u00e1 t\u1ef1 nhi\u00ean, c\u00f2n s\u1ef1 tuy\u1ec7t ch\u1ee7ng ng\u00e0y nay l\u1ea1i ch\u1ee7 y\u1ebfu l\u00e0 do ho\u1ea1t \u0111\u1ed9ng c\u1ee7a con ng\u01b0\u1eddi (Nguy\u1ec5n Ho\u00e0ng Ngh\u0129a, 1999).<\/p>\n

Nh\u00ecn chung, r\u1eebng nhi\u1ec7t \u0111\u1edbi (khu v\u1ef1c c\u00f3 \u0111a d\u1ea1ng sinh h\u1ecdc cao nh\u1ea5t) \u0111ang c\u00f3 nguy c\u01a1 suy gi\u1ea3m v\u00e0 b\u1ecb ph\u00e2n c\u1eaft nghi\u00eam tr\u1ecdng v\u00e0 \u0111i c\u00f9ng v\u1edbi n\u00f3 l\u00e0 s\u1ef1 tuy\u1ec7t ch\u1ee7ng h\u00e0ng lo\u1ea1t c\u1ee7a v\u00f4 s\u1ed1 lo\u00e0i. Hi\u1ec7n nay, tr\u00ean th\u1ebf gi\u1edbi ch\u1ec9 c\u00f2n kho\u1ea3ng 5% di\u1ec7n t\u00edch r\u1eebng \u0111\u01b0\u1ee3c b\u1ea3o v\u1ec7 trong c\u00e1c khu r\u1eebng c\u1ea5m v\u00e0 ngay c\u1ea3 \u1edf ch\u00ednh nh\u1eefng khu r\u1eebng n\u00e0y, c\u0169ng th\u01b0\u1eddng xuy\u00ean b\u1ecb \u0111e do\u1ea1 t\u00e0n ph\u00e1. Ch\u1ec9 c\u00f3 4% di\u1ec7n t\u00edch r\u1eebng \u0111\u01b0\u1ee3c b\u1ea3o v\u1ec7 \u1edf ch\u00e2u Phi, 2% \u1edf ch\u00e2u M\u1ef9 La Tinh v\u00e0 6% \u1edf ch\u00e2u \u00e1. N\u1ebfu c\u0103n c\u1ee9 v\u00e0o nguy\u00ean l\u00fd t\u1ef7 l\u1ec7 gi\u1eefa di\u1ec7n t\u00edch v\u00e0 s\u1ed1 lo\u00e0i th\u00ec s\u1ed1 l\u01b0\u1ee3ng lo\u00e0i ch\u1eafc ch\u1eafn s\u1ebd b\u1ecb gi\u1ea3m \u0111i m\u1ea5t m\u1ed9t n\u1eeda. Nh\u01b0ng khi di\u1ec7n t\u00edch r\u1eebng \u0111\u00e3 m\u1ea5t \u0111i 90%, s\u1ed1 lo\u00e0i s\u1ebd kh\u00f4ng ph\u1ea3i c\u00f2n l\u1ea1i 10% m\u00e0 c\u00f3 khi c\u00f2n b\u1ecb m\u1ea5t t\u1ea5t c\u1ea3 v\u00ec cu\u1ed9c s\u1ed1ng c\u1ee7a ch\u00fang c\u00f3 th\u1ec3 ho\u00e0n to\u00e0n d\u1ef1a v\u00e0o c\u00e1c khu r\u1eebng \u0111\u00e3 b\u1ecb t\u00e0n ph\u00e1. Ngo\u00e0i ra, n\u1ebfu c\u00e1c lo\u00e0i n\u00e0o \u0111\u00f3 c\u00f3 c\u00f2n t\u1ed3n t\u1ea1i \u0111i n\u1eefa th\u00ec bi\u1ebfn d\u1ecb di truy\u1ec1n, t\u00e0i nguy\u00ean di truy\u1ec1n c\u1ee7a lo\u00e0i \u0111\u00e3 b\u1ecb gi\u1ea3m \u0111i \u0111\u00e1ng k\u1ec3 (Grain, 1992).<\/p>\n

Theo Wilson (1992) nguy\u00ean nh\u00e2n c\u1ee7a s\u1ef1 tuy\u1ec7t ch\u1ee7ng g\u1ed3m:<\/p>\n

\u00b7\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Ph\u00e1 hu\u1ef7 m\u00f4i tr\u01b0\u1eddng s\u1ed1ng \u0111e do\u1ea1 73% s\u1ed1 lo\u00e0i.<\/p>\n

\u00b7\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Nh\u1eadp n\u1ed9i lo\u00e0i m\u1edbi \u0111e do\u1ea1 68% s\u1ed1 lo\u00e0i.<\/p>\n

\u00b7\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 S\u1ef1 bi\u1ebfn \u0111\u1ed5i m\u00f4i tr\u01b0\u1eddng do ho\u00e1 ch\u1ea5t \u0111e do\u1ea1 38% s\u1ed1 lo\u00e0i.<\/p>\n

\u00b7\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Vi\u1ec7c lai v\u1edbi lo\u00e0i kh\u00e1c \u0111e do\u1ea1 38% s\u1ed1 lo\u00e0i.<\/p>\n

\u00b7\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Khai th\u00e1c qu\u00e1 m\u1ee9c \u0111e do\u1ea1 15% s\u1ed1 lo\u00e0i.<\/p>\n

Qu\u00e1 tr\u00ecnh m\u1ea5t \u0111a d\u1ea1ng di truy\u1ec1n bao g\u1ed3m:<\/p>\n

– X\u00f3i m\u00f2n di truy\u1ec1n<\/strong> (Genetic Erosion): Bao g\u1ed3m vi\u1ec7c m\u1ea5t nh\u1eefng gen \u0111\u01a1n l\u1ebb hay to\u00e0n b\u1ed9 c\u00e1c t\u1ed5 h\u1ee3p gen. Thu\u1eadt ng\u1eef \u201cX\u00f3i m\u00f2n di truy\u1ec1n\u201d ngh\u0129a h\u1eb9p \u0111\u01b0\u1ee3c hi\u1ec3u l\u00e0 s\u1ef1 m\u1ea5t c\u00e1c gen hay c\u00e1c alen, ngh\u0129a r\u1ed9ng l\u00e0 s\u1ef1 m\u1ea5t m\u00e1t c\u00e1c gi\u1ed1ng c\u00e2y tr\u1ed3ng (FAO, 1996).<\/p>\n

Con ng\u01b0\u1eddi l\u00e0 nguy\u00ean nh\u00e2n c\u01a1 b\u1ea3n c\u1ee7a s\u1ef1 m\u1ea5t \u0111a d\u1ea1ng di truy\u1ec1n v\u00ec trong qu\u00e1 tr\u00ecnh \u0111\u1ea3m b\u1ea3o cu\u1ed9c s\u1ed1ng, con ng\u01b0\u1eddi \u0111\u00e3 l\u00e0m bi\u1ebfn \u0111\u1ed5i m\u00f4i tr\u01b0\u1eddng theo h\u01b0\u1edbng b\u1ea5t l\u1ee3i. Vi\u1ec7c khai th\u00e1c r\u1eebng kh\u00f4ng h\u1ee3p l\u00fd, ph\u00e1 r\u1eebng l\u00e0m r\u00e3y, ho\u1eb7c cho m\u1ed9t m\u1ee5c \u0111\u00edch kh\u00e1c l\u00e0 nguy\u00ean nh\u00e2n ch\u1ee7 y\u1ebfu d\u1eabn \u0111\u1ebfn x\u00f3i m\u00f2n t\u00e0i nguy\u00ean c\u00e2y r\u1eebng, c\u00e2y thu\u1ed1c qu\u00fd hi\u1ebfm v\u00e0 c\u00e1c c\u00e2y hoang d\u1ea1i c\u00f3 h\u1ecd h\u00e0ng xa g\u1ea7n v\u1edbi c\u00e2y tr\u1ed3ng (FAO,1995).<\/p>\n

Ti\u1ebfp \u0111\u1ebfn l\u00e0 nh\u1eefng ti\u1ebfn b\u1ed9 trong n\u1ec1n n\u00f4ng nghi\u1ec7p th\u00e2m canh t\u0103ng n\u0103ng su\u1ea5t; s\u1ef1 \u0111a d\u1ea1ng di truy\u1ec1n trong lo\u00e0i, \u0111\u01b0\u1ee3c th\u1ec3 hi\u1ec7n \u1edf v\u00f4 s\u1ed1 c\u00e1c gi\u1ed1ng c\u00e2y tr\u1ed3ng kh\u00e1c nhau t\u1eeb bao \u0111\u1eddi nay \u0111\u00e3 v\u00e0 \u0111ang b\u1ecb mai m\u1ed9t \u0111i m\u1ed9t c\u00e1ch nghi\u00eam tr\u1ecdng. H\u00e0ng lo\u1ea1t c\u00e1c gi\u1ed1ng c\u1ed5 truy\u1ec1n \u0111\u00e3 th\u00edch nghi v\u1edbi \u0111i\u1ec1u ki\u1ec7n \u0111\u1ea5t \u0111ai kh\u00ed h\u1eadu c\u1ee7a t\u1eebng \u0111\u1ecba ph\u01b0\u01a1ng \u0111\u00e3 b\u1ecb thay th\u1ebf cho c\u00e1c gi\u1ed1ng m\u1edbi c\u00f3 n\u0103ng su\u1ea5t cao.<\/p>\n

\u1ede Trung Qu\u1ed1c, kho\u1ea3ng 10 000 gi\u1ed1ng l\u00faa m\u1ef3 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong s\u1ea3n xu\u1ea5t n\u0103m 1949 v\u00e0 ch\u1ec9 c\u00f2n kho\u1ea3ng 1000 gi\u1ed1ng trong nh\u1eefng n\u0103m 1970. \u1edf M\u1ef9, trong s\u1ed1 7098 gi\u1ed1ng t\u00e1o \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng t\u1eeb n\u0103m 1804 \u0111\u1ebfn 1904 th\u00ec \u0111\u00e3 c\u00f3 86% b\u1ecb m\u1ea5t. T\u01b0\u01a1ng t\u1ef1, 95% c\u00e1c gi\u1ed1ng b\u1eafp c\u1ea3i, 91% gi\u1ed1ng ng\u00f4, 94% gi\u1ed1ng \u0111\u1eadu\u00a0 v\u00e0 81 % gi\u1ed1ng khoai t\u00e2y \u0111\u00e3 kh\u00f4ng c\u00f2n t\u1ed3n t\u1ea1i (Fowler, 1994).<\/p>\n

– Nguy c\u01a1 do thu h\u1eb9p di truy\u1ec1n<\/strong> (Genetic Vulnerability): Th\u1ea3m ho\u1ea1 n\u00e0y x\u1ea3y ra khi m\u1ed9t gi\u1ed1ng c\u00e2y n\u00e0o \u0111\u00f3 \u0111\u01b0\u1ee3c tr\u1ed3ng tr\u00ean m\u1ed9t di\u1ec7n t\u00edch l\u1edbn, do \u0111\u00f3 d\u1ec5 d\u1eabn \u0111\u1ebfn b\u1ecb nhi\u1ec5m s\u00e2u b\u1ec7nh v\u00e0 c\u00e1c th\u1ea3m ho\u1ea1 m\u00f4i tr\u01b0\u1eddng. Hai y\u1ebfu t\u1ed1 c\u00f3 li\u00ean quan \u0111\u1ebfn thu h\u1eb9p di truy\u1ec1n l\u00e0: Di\u1ec7n t\u00edch \u0111\u1ea5t d\u00e0nh cho vi\u1ec7c gieo tr\u1ed3ng c\u1ee7a t\u1eebng gi\u1ed1ng v\u00e0 m\u1ee9c \u0111\u1ed3ng nh\u1ea5t c\u1ee7a gi\u1ed1ng c\u00e2y tr\u1ed3ng \u0111\u00f3. N\u0103m 1982, di\u1ec7n t\u00edch gieo tr\u1ed3ng gi\u1ed1ng l\u00faa \u201cIR 36\u201d l\u00ean t\u1edbi 11 tri\u1ec7u ha \u1edf Ch\u00e2u \u00e1. V\u00e0o n\u0103m 1983 gi\u1ed1ng l\u00faa m\u1ef3 \u201cSonalika\u201d \u0111\u00e3 \u0111\u01b0\u1ee3c tr\u1ed3ng tr\u00ean 67 % di\u1ec7n t\u00edch \u0111\u1ea5t tr\u1ed3ng l\u00faa m\u1ef3 c\u1ee7a B\u0103ngladesh . N\u0103m 1990, gi\u1ed1ng l\u00faa lai F1 chi\u1ebfm tr\u00ean 15 tri\u1ec7u ha \u0111\u1ea5t \u1edf Trung Qu\u1ed1c. Vi\u1ec7c gieo tr\u1ed3ng m\u1ed9t lo\u1ea1i c\u00e2y tr\u00ean di\u1ec7n t\u00edch l\u1edbn c\u00f3 th\u1ec3 d\u1eabn \u0111\u1ebfn th\u1ea3m ho\u1ea1 khi c\u00e2y tr\u1ed3ng \u0111\u00f3 b\u1ecb nhi\u1ec5m s\u00e2u b\u1ec7nh. C\u00e1c v\u00ed d\u1ee5 \u0111i\u1ec3n h\u00ecnh nh\u01b0 n\u1ea1n \u0111\u00f3i do d\u1ecbch b\u1ec7nh khoai t\u00e2y (Phytopthera infestan<\/em>) \u1edf Ch\u00e2u \u00c2u v\u00e0 B\u1eafc M\u1ef9 t\u1eeb n\u0103m 1845- 1848, d\u1eabn t\u1edbi c\u00e1c ch\u1ebft c\u1ee7a 1,5 tri\u1ec7u ng\u01b0\u1eddi Aix\u01a1len. \u1edf M\u1ef9, n\u0103m 1970 b\u1ec7nh ch\u00e1y l\u00e1 ng\u00f4 \u0111\u00e3 ph\u00e1 hu\u1ef7 to\u00e0n b\u1ed9 v\u00e0nh \u0111ai ng\u00f4 v\u00e0 l\u00e0m m\u1ea5t kho\u1ea3ng 15 % s\u1ea3n l\u01b0\u1ee3ng ng\u00f4 c\u1ee7a n\u01b0\u1edbc n\u00e0y. T\u1eeb n\u0103m 1970 \u0111\u1ebfn 1980 b\u1ec7nh g\u1ec9 s\u1eaft \u0111\u00e3 t\u00e0n ph\u00e1 40 % di\u1ec7n t\u00edch m\u00eda v\u00e0 l\u00e0m thi\u1ec7t h\u1ea1i h\u01a1n m\u1ed9t tri\u1ec7u t\u1ea5n \u0111\u01b0\u1eddng c\u1ee7a Cuba (Fowler, 1994).<\/p>\n

– Hu\u1ef7 di\u1ec7t di truy\u1ec1n <\/strong>(Genetic Wipeout): S\u1ef1 m\u1ea5t \u0111a d\u1ea1ng di truy\u1ec1n c\u00f2n do nh\u1eefng nguy\u00ean nh\u00e2n nh\u01b0 chi\u1ebfn tranh, ho\u1ea3 ho\u1ea1n, do nh\u1eefng b\u1ea5t c\u1ea9n, thi\u1ebfu tr\u00e1ch nhi\u1ec7m trong c\u00f4ng t\u00e1c qu\u1ea3n l\u00fd, \u0111\u00f4i khi c\u00f2n do \u0111\u1eddi s\u1ed1ng c\u1ee7a ng\u01b0\u1eddi d\u00e2n qu\u00e1 kh\u00f3 kh\u0103n (FAO, 1996).<\/p>\n

Xem t\u00e0i li\u1ec7u tham kh\u1ea3o t\u1ea1i \u0111\u00e2y<\/a>.<\/td>\n<\/tr>\n

TS. Tr\u1ea7n Danh S\u1eedu<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"excerpt":{"rendered":"

\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Trong cu\u1ed9c s\u1ed1ng, s\u1ef1 tuy\u1ec7t ch\u1ee7ng lu\u00f4n lu\u00f4n \u0111\u1ed3ng h\u00e0nh v\u1edbi s\u1ef1 b\u1eaft \u0111\u1ea7u v\u00e0 h\u00ecnh th\u00e0nh c\u00e1c sinh<\/p>\n","protected":false},"author":4,"featured_media":280,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[38],"tags":[],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/prc.org.vn\/index.php?rest_route=\/wp\/v2\/posts\/775"}],"collection":[{"href":"https:\/\/prc.org.vn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prc.org.vn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prc.org.vn\/index.php?rest_route=\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/prc.org.vn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=775"}],"version-history":[{"count":1,"href":"https:\/\/prc.org.vn\/index.php?rest_route=\/wp\/v2\/posts\/775\/revisions"}],"predecessor-version":[{"id":776,"href":"https:\/\/prc.org.vn\/index.php?rest_route=\/wp\/v2\/posts\/775\/revisions\/776"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/prc.org.vn\/index.php?rest_route=\/wp\/v2\/media\/280"}],"wp:attachment":[{"href":"https:\/\/prc.org.vn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=775"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prc.org.vn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=775"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prc.org.vn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=775"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}