S\u00e2u \u0111\u1ee5c n\u00f5n Hypsipyla robusta<\/em> th\u01b0\u1eddng h\u1ea1i m\u1ed9t s\u1ed1 lo\u00e0i c\u00e2y h\u1ecd xoan \u0111\u1eb7c bi\u1ec7t l\u00e0 c\u00e1c lo\u00e0i c\u00e2y thu\u1ed9c ph\u00e2n h\u1ecd Swietenioideae trong \u0111\u00f3 c\u00f3 m\u1ed9t s\u1ed1 lo\u00e0i c\u00f3 gi\u00e1 tr\u1ecb kinh t\u1ebf cao nh\u01b0 l\u00e1t (Chukrasia tabularis<\/em>), xoan m\u1ed9c (Toona sureni<\/em>), l\u00e1t m\u00eahic\u00f4 (Cedrela odorata<\/em>), x\u00e0 c\u1eeb (Khaya senegalensis<\/em>)… M\u1ee9c \u0111\u1ed9 ph\u00e1 h\u1ea1i n\u1eb7ng c\u1ee7a s\u00e2u \u0111\u1ee5c n\u00f5n H. robusta <\/em>th\u01b0\u1eddng th\u1ea5y \u1edf c\u00e1c r\u1eebng tr\u1ed3ng t\u1eeb 1-3 n\u0103m tu\u1ed5i. S\u00e2u non th\u01b0\u1eddng \u0111\u1ee5c ch\u1ed3i v\u00e0 n\u00f5n c\u1ee7a c\u00e1c lo\u00e0i c\u00e2y n\u00e0y, \u0111\u1eb7c bi\u1ec7t l\u00e0 \u0111\u1ec9nh sinh tr\u01b0\u1edfng khi b\u1ecb s\u00e2u h\u1ea1i th\u01b0\u1eddng ch\u1ebft. Sau \u0111\u00f3 m\u1ed9t th\u1eddi gian c\u00e1c ch\u1ed3i b\u00ean m\u1edbi ph\u00e1t tri\u1ec3n t\u1eeb ph\u1ea7n d\u01b0\u1edbi c\u1ee7a \u0111\u1ec9nh sinh tr\u01b0\u1edfng \u0111\u00e3 b\u1ecb ch\u1ebft. S\u1ef1 ph\u00e1 h\u1ea1i nh\u01b0 v\u1eady th\u01b0\u1eddng l\u00e0m c\u00e2y h\u1ea1n ch\u1ebf ph\u00e1t tri\u1ec3n chi\u1ec1u cao, th\u00e2n th\u01b0\u1eddng b\u1ecb d\u1ecb d\u1ea1ng (kh\u00f4ng th\u1eb3ng), do \u0111\u00f3 l\u00e0m gi\u1ea3m n\u0103ng su\u1ea5t v\u00e0 ch\u1ea5t l\u01b0\u1ee3ng g\u1ed7.<\/p>\n Vi\u1ec7c ph\u00f2ng tr\u1eeb lo\u00e0i s\u00e2u n\u00e0y \u0111\u00e3 \u0111\u01b0\u1ee3c m\u1ed9t s\u1ed1 n\u01b0\u1edbc tr\u00ean th\u1ebf gi\u1edbi \u0111\u1ec1 c\u1eadp v\u00e0 nghi\u00ean c\u1ee9u nh\u01b0ng r\u1ea5t \u00edt hi\u1ec7u qu\u1ea3 v\u00ec s\u00e2u th\u01b0\u1eddng n\u1eb1m trong n\u00f5n c\u00e2y n\u00ean c\u00e1c lo\u1ea1i thu\u1ed1c tr\u1eeb s\u00e2u r\u1ea5t kh\u00f3 ti\u1ebfp x\u00fac. Tuy nhi\u00ean, trong qu\u00e1 tr\u00ecnh nghi\u00ean c\u1ee9u v\u1ec1 lo\u00e0i s\u00e2u n\u00e0y ng\u01b0\u1eddi ta \u0111\u00e3 ph\u00e1t hi\u1ec7n th\u1ea5y sau khi n\u1edf t\u1eeb tr\u1ee9ng, s\u00e2u tu\u1ed5i 1-2 th\u01b0\u1eddng lang thang b\u00ean ngo\u00e0i \u0103n c\u00e1c l\u00e1 non sau \u0111\u00f3 m\u1edbi \u0111\u1ee5c v\u00e0o trong n\u00f5n \u0111\u1ec3 ti\u1ebfp t\u1ee5c ho\u00e0n th\u00e0nh v\u00f2ng \u0111\u1eddi. N\u1ebfu vi\u1ec7c \u0111i\u1ec1u tra x\u00e1c \u0111\u1ecbnh tu\u1ed5i s\u00e2u trung b\u00ecnh tr\u00ean hi\u1ec7n tr\u01b0\u1eddng l\u00e0m t\u1ed1t ta c\u00f3 th\u1ec3 x\u00e1c \u0111\u1ecbnh \u0111\u01b0\u1ee3c th\u1eddi gian xu\u1ea5t hi\u1ec7n s\u00e2u tu\u1ed5i 1-2 v\u00e0 d\u1ec5 d\u00e0ng ph\u00f2ng tr\u1eeb b\u1eb1ng c\u00e1c lo\u00e0i thu\u1ed1c tr\u1eeb s\u00e2u th\u00f4ng th\u01b0\u1eddng.<\/p>\n V\u00ec s\u00e2u non th\u01b0\u1eddng n\u1eb1m trong n\u00f5n n\u00ean vi\u1ec7c x\u00e1c \u0111\u1ecbnh tu\u1ed5i s\u00e2u ph\u1ea3i b\u00f3c n\u00f5n \u0111\u1ec3 quan s\u00e1t s\u00e2u non; \u0111i\u1ec1u n\u00e0y r\u1ea5t b\u1ea5t ti\u1ec7n v\u00e0 m\u1ea5t th\u1eddi gian. Nh\u01b0ng n\u1ebfu d\u1ef1a v\u00e0o k\u00edch th\u01b0\u1edbc vi\u00ean ph\u00e2n \u0111\u00f9n ra \u1edf b\u00ean ngo\u00e0i \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh tu\u1ed5i s\u00e2u b\u00ean trong n\u00f5n c\u00f4ng vi\u1ec7c s\u1ebd ti\u1ebfn h\u00e0nh thu\u1eadn l\u1ee3i v\u00e0 t\u1ed1n \u00edt th\u1eddi gian h\u01a1n nhi\u1ec1u. Vi\u1ec7c x\u00e1c \u0111\u1ecbnh t\u01b0\u01a1ng quan gi\u1eefa k\u00edch th\u01b0\u1edbc ph\u00e2n s\u00e2u v\u00e0 k\u00edch th\u01b0\u1edbc m\u1ea3nh \u0111\u1ea7u c\u1ee7a s\u00e2u non H. robusta <\/em>s\u1ebd cho ph\u00e9p d\u1ef1a v\u00e0o k\u00edch th\u01b0\u1edbc ph\u00e2n s\u00e2u b\u00ean ngo\u00e0i \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh tu\u1ed5i s\u00e2u non \u1edf b\u00ean trong n\u00f5n.<\/p>\n 2. V\u1eadt li\u1ec7u v\u00e0 ph\u01b0\u01a1ng ph\u00e1p nghi\u00ean c\u1ee9u.<\/strong><\/p>\n – Qu\u00e1 tr\u00ecnh g\u00e2y nu\u00f4i s\u00e2u \u0111\u1ee5c n\u00f5n H. robusta<\/em> trong ph\u00f2ng th\u00ed nghi\u1ec7m c\u0169ng nh\u01b0 \u0111i\u1ec1u tra v\u00e0 quan s\u00e1t t\u1ea1i hi\u1ec7n tr\u01b0\u1eddng cho th\u1ea5y c\u00e1c m\u1eabu ph\u00e2n thu \u0111\u01b0\u1ee3c \u1edf c\u00e1c tu\u1ed5i s\u00e2u non kh\u00e1c nhau c\u00f3 k\u00edch th\u01b0\u1edbc kh\u00e1c nhau. Tuy nhi\u00ean, k\u00edch th\u01b0\u1edbc chi\u1ec1u r\u1ed9ng ph\u00e2n s\u00e2u \u1edf t\u1eebng tu\u1ed5i \u1ed5n \u0111\u1ecbnh h\u01a1n r\u1ea5t nhi\u1ec1u so v\u1edbi k\u00edch th\u01b0\u1edbc chi\u1ec1u d\u00e0i c\u1ee7a ph\u00e2n, v\u00ec v\u1eady y\u1ebfu t\u1ed1 chi\u1ec1u r\u1ed9ng c\u1ee7a ph\u00e2n \u0111\u01b0\u1ee3c ch\u1ecdn \u0111\u1ec3 ti\u1ebfn h\u00e0nh x\u00e1c \u0111\u1ecbnh m\u1ed1i t\u01b0\u01a1ng quan gi\u1eefa k\u00edch th\u01b0\u1edbc ph\u00e2n v\u00e0 tu\u1ed5i c\u1ee7a s\u00e2u non H. robusta. <\/em><\/p>\n – S\u00e2u non c\u00e1c tu\u1ed5i c\u00f3 k\u00edch th\u01b0\u1edbc c\u01a1 th\u1ec3 v\u00e0 k\u00edch th\u01b0\u1edbc m\u1ea3nh \u0111\u1ea7u kh\u00e1c nhau. Tuy nhi\u00ean, k\u00edch th\u01b0\u1edbc c\u01a1 th\u1ec3 s\u00e2u non bi\u1ebfn \u0111\u1ed9ng r\u1ea5t l\u1edbn, nh\u01b0ng k\u00edch th\u01b0\u1edbc chi\u1ec1u r\u1ed9ng m\u1ea3nh \u0111\u1ea7u l\u1ea1i c\u00f3 t\u00ednh \u1ed5n \u0111\u1ecbnh h\u01a1n v\u00ec v\u1eady trong nghi\u00ean c\u1ee9u c\u00f4n tr\u00f9ng ng\u01b0\u1eddi ta th\u01b0\u1eddng x\u00e1c \u0111\u1ecbnh k\u00edch th\u01b0\u1edbc chi\u1ec1u ngang m\u1ea3nh \u0111\u1ea7u \u0111\u1ec3 t\u00ednh tu\u1ed5i s\u00e2u. Do \u0111\u00f3 s\u1ed1 li\u1ec7u \u0111\u1ec3 t\u00ednh t\u01b0\u01a1ng quan \u1edf \u0111\u00e2y l\u00e0 k\u00edch th\u01b0\u1edbc chi\u1ec1u ngang vi\u00ean ph\u00e2n c\u00e1c tu\u1ed5i v\u00e0 k\u00edch th\u01b0\u1edbc chi\u1ec1u ngang m\u1ea3nh \u0111\u1ea7u c\u00e1c tu\u1ed5i c\u1ee7a s\u00e2u non.<\/p>\n Ph\u01b0\u01a1ng ph\u00e1p ti\u1ebfn h\u00e0nh th\u00ed nghi\u1ec7m:<\/em><\/p>\n C\u00e1c n\u00f5n c\u00e2y l\u00e1t c\u00f3 chi\u1ec1u d\u00e0i 20- 30 cm \u0111\u01b0\u1ee3c thu th\u1eadp t\u1eeb v\u01b0\u1eddn th\u00ed nghi\u1ec7m, sau khi \u0111\u01b0a s\u00e2u tu\u1ed5i 1 v\u00e0o n\u00f5n s\u1ebd \u0111\u01b0\u1ee3c nu\u00f4i ri\u00eang r\u1ebd trong c\u00e1c \u1ed1ng nghi\u1ec7m thu\u1ef7 tinh l\u1edbn c\u00f3 \u0111\u01b0\u1eddng k\u00ednh 4 cm; m\u1ed7i \u0111\u1ee3t nu\u00f4i g\u1ed3m 20 \u0111\u1ebfn 30 c\u00e1 th\u1ec3 s\u00e2u.<\/p>\n H\u00e0ng ng\u00e0y thu th\u1eadp c\u00e1c ph\u00e2n s\u00e2u \u0111\u00f9n ra \u0111\u01b0a v\u00e0o \u0111\u0129a petri v\u00e0 ch\u1ecdn ng\u1eabu nhi\u00ean kho\u1ea3ng 30-50 vi\u00ean ph\u00e2n \u0111\u1ec3 ti\u1ebfn h\u00e0nh \u0111o chi\u1ec1u r\u1ed9ng. Hai ng\u00e0y m\u1ed9t l\u1ea7n m\u1edf c\u00e1c n\u00f5n \u0111\u1ec3 ki\u1ec3m tra t\u00ecnh tr\u1ea1ng s\u00e2u non v\u00e0 thu th\u1eadp m\u1ea3nh \u0111\u1ea7u n\u1ebfu c\u00f3. K\u00edch th\u01b0\u1edbc chi\u1ec1u r\u1ed9ng c\u1ee7a vi\u00ean ph\u00e2n v\u00e0 m\u1ea3nh \u0111\u1ea7u c\u00f9ng tu\u1ed5i s\u1ebd \u0111\u01b0\u1ee3c ghi l\u1ea1i \u0111\u1ec3 x\u1eed l\u00fd. Kho\u1ea3ng 4 \u0111\u1ebfn 5 ng\u00e0y thay n\u00f5n m\u1edbi \u0111\u1ec3 b\u1ea3o \u0111\u1ea3m th\u1ee9c \u0103n t\u01b0\u01a1i cho s\u00e2u non; vi\u1ec7c chuy\u1ec3n s\u00e2u sang n\u00f5n m\u1edbi \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng b\u1eb1ng b\u00fat l\u00f4ng m\u1ec1m. S\u1eed d\u1ee5ng ph\u01b0\u01a1ng ph\u00e1p \u0111\u00e1nh gi\u00e1 c\u1ee7a Mo & Tanton (1995) v\u00e0 x\u1eed l\u00fd s\u1ed1 li\u1ec7u b\u1eb1ng m\u00e1y t\u00ednh tr\u00ean ch\u01b0\u01a1ng tr\u00ecnh Excel 7.0.<\/p>\n Ph\u01b0\u01a1ng ph\u00e1p tr\u00ean c\u0169ng \u0111\u01b0\u1ee3c ti\u1ebfn h\u00e0nh tr\u00ean c\u00e1c c\u00e2y 1-2 tu\u1ed5i t\u1ea1i v\u01b0\u1eddn th\u00ed nghi\u1ec7m; k\u1ebft qu\u1ea3 cho th\u1ea5y c\u00e1c s\u1ed1 li\u1ec7u thu \u0111\u01b0\u1ee3c kh\u00f4ng c\u00f3 s\u1ef1 kh\u00e1c bi\u1ec7t nhi\u1ec1u so v\u1edbi nu\u00f4i trong ph\u00f2ng th\u00ed nghi\u1ec7m.<\/p>\n 2.K\u1ebft qu\u1ea3 nghi\u00ean c\u1ee9u v\u00e0 th\u1ea3o lu\u1eadn <\/strong><\/p>\n K\u1ebft qu\u1ea3<\/em><\/strong><\/p>\n Sau khi thu th\u1eadp \u0111\u1ea7y \u0111\u1ee7 c\u00e1c s\u1ed1 li\u1ec7u t\u1ea1i ph\u00f2ng th\u00ed nghi\u1ec7m v\u00e0 hi\u1ec7n tr\u01b0\u1eddng, \u0111\u1ec1 t\u00e0i \u0111\u00e3 x\u00e1c \u0111\u1ecbnh \u0111\u01b0\u1ee3c k\u00edch th\u01b0\u1edbc chi\u1ec1u r\u1ed9ng vi\u00ean ph\u00e2n v\u00e0 chi\u1ec1u r\u1ed9ng m\u1ea3nh \u0111\u1ea7u t\u01b0\u01a1ng \u1ee9ng \u1edf c\u00e1c tu\u1ed5i s\u00e2u. C\u00e1c k\u1ebft qu\u1ea3 \u0111\u01b0\u1ee3c th\u1ec3 hi\u1ec7n tr\u00ean b\u1ea3ng sau:<\/p>\n B\u1ea3ng k\u00edch th\u01b0\u1edbc chi\u1ec1u r\u1ed9ng ph\u00e2n s\u00e2u v\u00e0 k\u00edch th\u01b0\u1edbc chi\u1ec1u r\u1ed9ng m\u1ea3nh \u0111\u1ea7u c\u00e1c tu\u1ed5i s\u00e2u tu\u01a1ng \u1ee9ng c\u1ee7a s\u00e2u \u0111\u1ee5c n\u00f5n H. robusta.<\/em><\/strong><\/p>\n (mm)<\/strong><\/td>\n (mm)<\/strong><\/td>\n<\/tr>\n \u0110\u1ec1 t\u00e0i \u0111\u00e3 ti\u1ebfn h\u00e0nh ph\u00e2n t\u00edch t\u01b0\u01a1ng quan gi\u1eefa k\u00edch th\u01b0\u1edbc chi\u1ec1u r\u1ed9ng vi\u00ean ph\u00e2n v\u00e0 chi\u1ec1u r\u1ed9ng m\u1ea3nh \u0111\u1ea7u t\u01b0\u01a1ng \u1ee9ng \u1edf c\u00e1c tu\u1ed5i, k\u1ebft qu\u1ea3 cho th\u1ea5y: R t\u01b0\u01a1ng quan l\u00e0: 0,89<\/p>\n V\u1edbi R l\u00e0: 0,89 th\u00ec h\u1ec7 s\u1ed1 tu\u01a1ng quan gi\u1eefa k\u00edch th\u01b0\u1edbc chi\u1ec1u r\u1ed9ng vi\u00ean ph\u00e2n v\u00e0 k\u00edch th\u01b0\u1edbc chi\u1ec1u ngang m\u1ea3nh \u0111\u1ea7u c\u1ee7a s\u00e2u non H. robusta<\/em> l\u00e0 r\u1ea5t ch\u1eb7t ch\u1ebd. V\u00ec v\u1eady, c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng k\u00edch th\u01b0\u1edbc chi\u1ec1u r\u1ed9ng vi\u00ean ph\u00e2n \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh tu\u1ed5i s\u00e2u v\u00e0 s\u1ebd cho k\u1ebft qu\u1ea3 \u0111\u00e1ng tin c\u1eady<\/p>\n Bi\u1ec3u \u0111\u1ed3 t\u01b0\u01a1ng quan gi\u1eefa k\u00edch th\u01b0\u1edbc chi\u1ec1u r\u1ed9ng vi\u00ean ph\u00e2n v\u00e0 k\u00edch th\u01b0\u1edbc chi\u1ec1u ngang m\u1ea3nh \u0111\u1ea7u c\u1ee7a s\u00e2u non H. robusta.<\/em><\/strong><\/p>\n Th\u1ea3o lu\u1eadn<\/em><\/strong><\/p>\n T\u1eeb nh\u1eefng k\u1ebft qu\u1ea3 tr\u00ean ta th\u1ea5y:<\/p>\n – D\u1ef1a v\u00e0o k\u00edch th\u01b0\u1edbc ph\u00e2n s\u00e2u \u1edf b\u00ean ngo\u00e0i t\u00ednh \u0111\u01b0\u1ee3c ta c\u00f3 th\u1ec3 \u0111\u00e1nh gi\u00e1 \u0111\u01b0\u1ee3c tu\u1ed5i s\u00e2u \u0111ang s\u1ed1ng \u1edf trong n\u00f5n.<\/p>\n – Trong su\u1ed1t qu\u00e1 tr\u00ecnh s\u1ed1ng c\u1ee7a s\u00e2u \u0111\u1ee5c n\u00f5n H. robusta<\/em> kh\u00f4ng k\u1ec3 giai \u0111o\u1ea1n tr\u1ee9ng th\u00ec ch\u1ec9 c\u00f3 giai \u0111o\u1ea1n s\u00e2u tr\u01b0\u1edfng th\u00e0nh v\u00e0 s\u00e2u non tu\u1ed5i 1 v\u00e0 2 s\u1ed1ng \u1edf b\u00ean ngo\u00e0i (kh\u00f4ng \u1edf trong n\u00f5n) n\u00ean c\u00f3 th\u1ec3 d\u1ec5 d\u00e0ng di\u1ec7t ch\u00fang b\u1eb1ng c\u00e1c lo\u1ea1i thu\u1ed1c ho\u00e1 h\u1ecdct v\u00e0 ch\u1ebf ph\u1ea9m sinh h\u1ecdc. V\u00ec v\u1eady vi\u1ec7c x\u00e1c \u0111\u1ecbnh ch\u00ednh x\u00e1c th\u1eddi gian xu\u1ea5t hi\u1ec7n c\u1ee7a s\u00e2u tr\u01b0\u1edfng th\u00e0nh v\u00e0 s\u00e2u non tu\u1ed5i 1-2 l\u00e0 r\u1ea5t c\u1ea7n thi\u1ebft cho vi\u1ec7c quy\u1ebft \u0111\u1ecbnh khi n\u00e0o ti\u1ebfn h\u00e0nh ph\u00f2ng tr\u1eeb. Th\u00f4ng qua \u0111i\u1ec1u tra m\u1eadt \u0111\u1ed9 qu\u1ea7n th\u1ec3 s\u00e2u h\u1ea1i t\u1ea1i hi\u1ec7n tr\u01b0\u1eddng, bi\u1ebft \u0111\u01b0\u1ee3c tu\u1ed5i s\u00e2u trong th\u1ebf h\u1ec7 v\u00e0 th\u1eddi gian c\u1ee7a c\u00e1c pha ph\u00e1t tri\u1ec3n ta c\u00f3 th\u1ec3 x\u00e1c \u0111\u1ecbnh th\u1eddi \u0111i\u1ec3m xu\u1ea5t hi\u1ec7n s\u00e2u tr\u01b0\u1edfng th\u00e0nh v\u00e0 s\u00e2u non tu\u1ed5i 1-2.<\/p>\n Nh\u01b0 v\u1eady c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng ph\u01b0\u01a1ng ph\u00e1p n\u00e0y \u0111\u1ec3 t\u00ednh \u0111\u01b0\u1ee3c tu\u1ed5i s\u00e2u non H. robusta <\/em>th\u00f4ng qua chi\u1ec1u r\u1ed9ng ph\u00e2n m\u00e0 kh\u00f4ng c\u1ea7n t\u00e1ch c\u00e1c n\u00f5n \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh tu\u1ed5i s\u00e2u. Ph\u01b0\u01a1ng ph\u00e1p tr\u00ean s\u1ebd gi\u00fap ng\u01b0\u1eddi \u0111i\u1ec1u tra x\u00e1c \u0111\u1ecbnh nhanh s\u1ed1 l\u01b0\u1ee3ng v\u00e0 tu\u1ed5i s\u00e2u trung b\u00ecnh t\u1ea1i hi\u1ec7n tr\u01b0\u1eddng t\u1eeb \u0111\u00f3 c\u00f3 quy\u1ebft \u0111\u1ecbnh phun thu\u1ed1c hay kh\u00f4ng v\u00e0 n\u1ebfu phun th\u00ec phun v\u00e0o l\u00fac n\u00e0o \u0111\u1ec3 c\u00f3 hi\u1ec7u qu\u1ea3 cao nh\u1ea5t.<\/p>\n T\u00e0i li\u1ec7u tham kh\u1ea3o<\/strong><\/p>\n 1- Griffiths M.W. (1996), The Biology and Ecology of Hypsipyla Shoot Borers, International Workshop on Hypsipyla, Kandy, Srilanka, 1996, ACIAR proceedings No.97, 2001, <\/em>pp. 74-80.<\/p>\n 2- Mo-J; Tanton-MT. 1995. Estimation of larval instars of Hypsipyla robusta<\/em> Moore(Lepidoptera: Pyralidae) by larval frass widths. Australian-Entomologist. 1995, 22: 2, 59-62; 4 ref.<\/p>\n Summary<\/strong><\/p>\n Shoot borer Hypsipyla robusta<\/em> is one of the insect species causing much damage to species of Meliaceae family such as Chukrasia tabularis, Toona sureni<\/em>\u2026. The control of the borers however meets with many difficulties as the larvae usually live inside the shoots, hardly contacted with insecticide, the control is therefore of low efficiency.<\/p>\n Observation on biological characteristics of H. robusta<\/em> shows that the chrysalis and the instars 1-2 usually live outside the shoot. If the time of these stages can be determined one can control this insect species by ordinary insecticides.<\/p>\n Research has been carried out on correlation between width of the frass and width of the head capsule of various instars. Research result shows that quick determination in the field on the instars ispossible through the width of the frass and combined with the understanding of biological characteristics of H. robusta <\/em>one can determine on the emergence of the chrysalis and the instars 1-2 for their effective control.<\/p>\n","protected":false},"excerpt":{"rendered":" Sâu \u0111\u1ee5c nõn Hypsipyla robusta th\u01b0\u1eddng h\u1ea1i m\u1ed9t s\u1ed1 loài cây h\u1ecd xoan \u0111\u1eb7c bi\u1ec7t là các loài cây thu\u1ed9c phân h\u1ecd Swietenioideae trong \u0111ó có m\u1ed9t s\u1ed1 loài có giá tr\u1ecb kinh t\u1ebf cao nh\u01b0 lát (Chukrasia tabularis), xoan m\u1ed9c (Toona sureni), lát mêhicô (Cedrela odorata), xà c\u1eeb (Khaya senegalensis)… M\u1ee9c \u0111\u1ed9 phá h\u1ea1i n\u1eb7ng c\u1ee7a sâu \u0111\u1ee5c nõn H. robusta th\u01b0\u1eddng th\u1ea5y \u1edf các r\u1eebng tr\u1ed3ng t\u1eeb 1-3 n\u0103m tu\u1ed5i. Sâu non th\u01b0\u1eddng \u0111\u1ee5c ch\u1ed3i và nõn c\u1ee7a các loài cây này, \u0111\u1eb7c bi\u1ec7t là \u0111\u1ec9nh sinh tr\u01b0\u1edfng khi b\u1ecb sâu h\u1ea1i th\u01b0\u1eddng ch\u1ebft.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[18],"tags":[],"_links":{"self":[{"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/posts\/8661"}],"collection":[{"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/comments?post=8661"}],"version-history":[{"count":2,"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/posts\/8661\/revisions"}],"predecessor-version":[{"id":19259,"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/posts\/8661\/revisions\/19259"}],"wp:attachment":[{"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/media?parent=8661"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/categories?post=8661"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vafs.gov.vn\/vn\/wp-json\/wp\/v2\/tags?post=8661"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}\n\n
\n Tu\u1ed5i s\u00e2u<\/strong><\/td>\n K\u00edch th\u01b0\u1edbc chi\u1ec1u r\u1ed9ng trung b\u00ecnh c\u1ee7a vi\u00ean ph\u00e2n<\/strong><\/p>\n K\u00edch th\u01b0\u1edbc chi\u1ec1u r\u1ed9ng trung b\u00ecnh c\u1ee7a m\u1ea3nh \u0111\u1ea7u<\/strong><\/p>\n \n Tu\u1ed5i 1<\/td>\n 0,21 \u00b1 0,01<\/td>\n 0,81 \u00b1 0,01<\/td>\n<\/tr>\n \n Tu\u1ed5i 2<\/td>\n 0,32 \u00b1 0,02<\/td>\n 1,03 \u00b1 0,03<\/td>\n<\/tr>\n \n Tu\u1ed5i 3<\/td>\n 0,45 \u00b1 0,03<\/td>\n 1,24 \u00b1 0,03<\/td>\n<\/tr>\n \n Tu\u1ed5i 4<\/td>\n 0,72 \u00b1 0,03<\/td>\n 1,53 \u00b1 0,05<\/td>\n<\/tr>\n \n Tu\u1ed5i 5<\/td>\n 1,02 \u00b1 0,02<\/td>\n 2,77 \u00b1 0,07<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n