KHOA HOC CONG NGHl DAIMH GIA KHA IMAIMG PHOIMG TRI CUA XA KHUAIM DOI Vbl IVAIVI Alternarla sp. GAY BEIVH LEIM LEP HAT TREIV LlJA Ly Himg', L6 Minh Tutag^ T6MTAT Nghien cuu duoc thuc hien nham tim ra chung nam Altemaria sp. gay benh lem lep hat lua nang nhat va tim ra cac chiing xa khuan co kha nang ddi khang cao voi nam Altemaria sp. trong dieu kien phong thi nghiem. Ddi voi thi nghiem khao sat kha nang gay hai ciia cac chiing nam Altemaria spp. duoc bd tri hoan toan nglu nhien vol 10 nghiem thuc (10 chung nam Altemaria spp. duoc thu thap va phan lap tai Can Tho. An Giang. Tra Vinh. Vinh Long va Sdc Trang) va 4 lan lap lai trong dieu kien nha ludi. Ket qua cho diay frong sd 10 chiing nam duoc phan lap thi chung .47fi?raa/7a.CKl-TV (thu thap tu mdng liia d huyen Cau Ke. dnh Tra Vinh) gay hai nang nhat vdi ty le hat benh 64.9% d 11 ngay sau chung bdnh. Ddi vol thi nghidm khao sat kha nang ddi khang cua cac chung xa khuan vdi nam Altemaria sp. cung dugc bd tri hoan toan ngSu nhien vdi 7 nghidm ttiiic la 7 chiing xa khuan (TG2.1. TG43. VL5.4. DT3.4. AG2.1. CT48. HG4.2) va 5 lan lap lai Uong dieu kien phdng thi nghiem. Ket qua cho thay 3 chiing xa khuan C14.8. DT3.4 va TG2.1 cd kha nang ddi khang cao so vol cac chiing cdn lai vdi ban kinh viing lic che lan lirot 23.00 mm; 7.00 mm; 5.00 mm va hieu suat ddi kbang lan loot 57.0%. 30.8% va 32.5% d 15 ngay sau khi bd tri thi nghidm. Ben canh dd. kha nang lic che su hmh thanh bao tu va su moc mam cua bao tii nam ^tema/raCKl-TV cda chung xa khujin CT4.8. DT3.4 va TG2.1 cung duoc thuc hien vdi 5 ISn lap lai trong didu kien phdng thi nghiem. Ket qua cho thay ca 3 chiing CT4.8. DT3.4 va TG2.1 deu the hidn kha nang lie che su hinh thanh bao tu cao vdi hieu qua uc che su hinh thanh bao tu lan luot la 47.8%; 41.9%; 30.4% oil ngay sau nudi lac va kha nang lic che su moc mam cda bao tu cao vdi hieu qua uc che su moc mam cda bao tu lan lugt la 42.2%; 43.2%; 25.4% d- 24 gid sau xir ly, Tii khda: Altemaria sp., benh lem lep hat, phdng trir sinh hQcxa khuan. 1. Mi BAU 'IP phuong lai ddng bang sdng Ciiu Long (Tran Thi . ,- „. , . , . . • , , - Thu Thuy, 2011). Dong bang sdng Cim Long augc biet den nhu la mdt kho lua gao cua ca nude, chiem hon 50% san Hi$n nay, ndng dan qua lam dung thudc hda hoc luong gao va 90% san lugng xuat khau gao ca nude ^°^^ Phong fri henh lem lep hat fren lua. hau qua (Vd Khac Huy. 2014). Tuy nhien. vdi dieu kien khi cua viec lam dung thudc cd the dan den hien higng hau ndng am, tap quan canh tac sa day va su dung ""^ ^<t^^ "ehzng thudc, lam giam nguon thien dich nhieu phan dam cua ndng dan da tao dieu kien thuan <:6 ^an frong hr nhidu cung nhu vi sinh vat cd ich loi cho mdt sd benh gay hai nghiem frgng (Nguydn t^ong dat va lam anh huong den mdi truong xung van Luc. 2013). Trong dd. hdnh lem lep hat lua la <l"™h (Tran Van Hai. 2005). Trong bien phap sinh mdt frong nhimg nguyen nhan chinh giy anh hudng hgc quan ly henh fren cay frong flii xa khuan la den nang suatv4 pham chat lua gao (Ou. 1985). Dac "'"''" " >*'"*' ''9' <=° '^^ " ^ 8 Phong trir sinh hoc bidt. nam Altemaria sp. it nhieu ky sinh va lay nhijm bfnh '^y rat hieu qua. Xa khuan uc che mam benh fren hat txasK khi thu hoach va thudng dugc tim thay •'^ng mdt sd eg cM; Uet khang sinh, ttft enzyme fren hat cd the gay ra cac dom den fren ndi nhu va PhS" S'^i vach te hao. cdng smh va ky smh... gdp ph4n lam giam chiit luong hat (Notteghem etal., ffalaniyandi et al, 2013). Cac nghien cuu gin day 1995) Trong cac nghien cuu gin day da ghi nhan cho thay xa khuin co kha nang phong fri mdt sd nim Altemaria padwickji li mdt frong nhung loii ^nh hai fren lua nhu benh dao dn do nim nim gay hai phd bidn fren nhifa gidng lua va nhidu Pynailana oryzae (Le Mmh Tuimg va Tran Thi Thu Em. 2014). benh ddm van do nim Rhizoctonia solani (Le Mmh Tudng va Ngd Thi Kim Ngan. 2014) b' h chiy bia la do vi khuan Xanthomonas ' Hoc vien cao hoc ngilnh Bao ve Thuc vat. Tmdng Dai hpc ^^^^^^^ ^^^^ ^ ^,__j^ . ^ ^ ^ ^^ ^^^^^ o^^zae fmo?Ndng nghiep. Trudng Dai hoc CJn Tho Ngan. 2015). Do «. viec nghien cuu xa khuan tiong 84 NONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 - THANG 7/2020
Transcript
KHOA HOC CONG NGHl
DAIMH GIA K H A IMAIMG P H O I M G TRI CUA XA KHUAIM DOI
V b l IVAIVI Alternarla sp . GAY BEIVH LEIM LEP HAT TREIV LlJA
Ly Himg', L6 Minh Tutag^
T6MTAT
Nghien cuu duoc thuc hien nham tim ra chung nam Altemaria sp. gay benh lem lep hat lua nang nhat va tim ra cac chiing xa khuan co kha nang ddi khang cao voi nam Altemaria sp. trong dieu kien phong thi nghiem. Ddi voi thi nghiem khao sat kha nang gay hai ciia cac chiing nam Altemaria spp. duoc bd tri hoan toan nglu nhien vol 10 nghiem thuc (10 chung nam Altemaria spp. duoc thu thap va phan lap tai Can Tho. An Giang. Tra Vinh. Vinh Long va Sdc Trang) va 4 lan lap lai trong dieu kien nha ludi. Ket qua cho diay frong sd 10 chiing nam duoc phan lap thi chung .47fi?raa/7a.CKl-TV (thu thap tu mdng liia d huyen Cau Ke. dnh Tra Vinh) gay hai nang nhat vdi ty le hat benh 64.9% d 11 ngay sau chung bdnh. Ddi vol thi nghidm khao sat kha nang ddi khang cua cac chung xa khuan vdi nam Altemaria sp. cung dugc bd tri hoan toan ngSu nhien vdi 7 nghidm ttiiic la 7 chiing xa khuan (TG2.1. TG43. VL5.4. DT3.4. AG2.1. CT48. HG4.2) va 5 lan lap lai Uong dieu kien phdng thi nghiem. Ket qua cho thay 3 chiing xa khuan C14.8. DT3.4 va TG2.1 cd kha nang ddi khang cao so vol cac chiing cdn lai vdi ban kinh viing lic che lan lirot 23.00 mm; 7.00 mm; 5.00 mm va hieu suat ddi kbang lan loot 57.0%. 30.8% va 32.5% d 15 ngay sau khi bd tri thi nghidm. Ben canh dd. kha nang lic che su hmh thanh bao tu va su moc mam cua bao tii nam ^tema/raCKl-TV cda chung xa khujin CT4.8. DT3.4 va TG2.1 cung duoc thuc hien vdi 5 ISn lap lai trong didu kien phdng thi nghiem. Ket qua cho thay ca 3 chiing CT4.8. DT3.4 va TG2.1 deu the hidn kha nang lie che su hinh thanh bao tu cao vdi hieu qua uc che su hinh thanh bao tu lan luot la 47.8%; 41.9%; 30.4% o i l ngay sau nudi lac va kha nang lic che su moc mam cda bao tu cao vdi hieu qua uc che su moc mam cda bao tu lan lugt la 42.2%; 43.2%; 25.4% d-24 gid sau xir ly,
Tii khda: Altemaria sp., benh lem lep hat, phdng trir sinh hQcxa khuan. 1. Mi BAU 'IP phuong lai ddng bang sdng Ciiu Long (Tran Thi
. , - „ . , . , . . • , , - Thu Thuy, 2011). Dong bang sdng Cim Long augc biet den nhu la
mdt kho lua gao cua ca nude, chiem hon 50% san Hi$n nay, ndng dan qua lam dung thudc hda hoc luong gao va 90% san lugng xuat khau gao ca nude ^°^^ Phong fri henh lem lep hat fren lua. hau qua (Vd Khac Huy. 2014). Tuy nhien. vdi dieu kien khi cua viec lam dung thudc cd the dan den hien higng hau ndng am, tap quan canh tac sa day va su dung " " ^ ^<t^^ "ehzng thudc, lam giam nguon thien dich nhieu phan dam cua ndng dan da tao dieu kien thuan <:6 ^an frong hr nhidu cung nhu vi sinh vat cd ich loi cho mdt sd benh gay hai nghiem frgng (Nguydn t^ong dat va lam anh huong den mdi truong xung van Luc. 2013). Trong dd. hdnh lem lep hat lua la <l"™h (Tran Van Hai. 2005). Trong bien phap sinh mdt frong nhimg nguyen nhan chinh giy anh hudng hgc quan ly henh fren cay frong flii xa khuan la den nang suatv4 pham chat lua gao (Ou. 1985). Dac " ' " ' ' " " >*'"*' ' '9 ' <=° '^^ " ^ 8 Phong trir sinh hoc bidt. nam Altemaria sp. it nhieu ky sinh va lay nhijm bfnh '^y rat hieu qua. Xa khuan uc che mam benh fren hat txasK khi thu hoach va thudng dugc tim thay •'^ng mdt sd eg cM; Uet khang sinh, ttft enzyme fren hat cd the gay ra cac dom den fren ndi nhu va PhS" S'^i vach te hao. cdng smh va ky smh... gdp ph4n lam giam chiit luong hat (Notteghem etal., ffalaniyandi et al, 2013). Cac nghien cuu gin day 1995) Trong cac nghien cuu gin day da ghi nhan cho thay xa khuin co kha nang phong fri mdt sd nim Altemaria padwickji l i mdt frong nhung loii ^ n h hai fren lua nhu benh dao dn do nim nim gay hai phd bidn fren nhifa gidng lua va nhidu Pynailana oryzae (Le Mmh Tuimg va Tran Thi Thu
Em. 2014). benh ddm van do nim Rhizoctonia solani (Le Mmh Tudng va Ngd Thi Kim Ngan. 2014) b' h chiy bia la do vi khuan Xanthomonas
' Hoc vien cao hoc ngilnh Bao ve Thuc vat. Tmdng Dai hpc ^^^^^^^ ^ ^ ^ ^ ^ ^ ,__j^ . ^ ^ ^ ^^ ^^^^^ o^^zae
fmo?Ndng nghiep. Trudng Dai hoc CJn Tho Ngan. 2015). Do « . viec nghien cuu xa khuan tiong
84 NONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 - THANG 7/2020
KHOA HQC CbNG NGHE
Altemaria sp. gay ra h-en liia la rat can thiet va cap b^ch.
2 . VAT UEU VA PHUONG PHAP NGHIEN CUU
2.1.V4tUeu
Ngudn xa khuan: 7 mlu xa khuan AG2.1, CT4.8, DT3.4, HGl.l, HG4.2, TG2.1 va VL5.4 duoc phong thi nghiem Benh cay, Bo mon Bao ve thuc vat, Truang Dai hgc Can Tha cung cap. Theo Vo Thi My Kim (2016), cac mlu xa khuan tren thupc chi Stieptomyces va duoc phan lap tir dat trong lua ciia nong din b dong bing song Cuu Long (DBSCL) va CO kha nang doi khang cao voi nam Pyricularia oryzae gay b^nh dao on hai liia cr DBSCL voi hieu suat doi khang dao dong 68,89% - 76,45%.
2.2. Phuong phAp nghidn ohi
2.2.1. Thu thap, phan lap cac chiing nam Altemaria spp. gay benh lem lep bat liia tai 5 tinh DBSCL
Phuong phap thu mdu. Mlu liia benh duoc thu thap tai ruong liia cua nong dan vao thai diem sap thu hoach. M6i mk\i chgn 2 ruong liia cimg giong, thu 20-30 bong liia bi lem lep hat roi cho vao bao giay dem v^ bao quan a nhiet do phong va tien hanh phan lap ngay.
Phuong phap phan lap nam: Dugc thuc hi^n bang phuong phap ti hat tren dia petri theo phuong phap Blotter OSTA, 1985) vai 25 hat lua/(Ka va 4 ^a/mlu benh.
Phan lap tach rong va xac dinh mam benh: Hat Ilia benh sau khi u duoc 5-7 ngay, dem quan sat duoi kinh soi noi de ghi nhan mau sic va each phat tri^n cua sm nam, su hien dien cua 6 nam, each mgc ciia soi nam tren hat liia. Dong thoi, tifin hanh lam tieu ban va quan sat duoi kinh hien vi quang hpc de mo ta hinh dang, mau sdc cua sgi nam, bao tii, ghi nhan kich thuoc ciia bao tu. Phan lap cac tac nhan gay hai tren hat liia, tach dong lam thuln nam Altemana bing phuong phap cay truyfin tir dinh sinh truang spi nam theo phuong phap cua Burgess et al. (2008). Dua theo khoa phan loai cua Bamett va Hunter (1998), Mew va Gonzales (2002) va Pitt va Hocking (2009) d^ xac dmh den chi nlm Altemaria.
2.2.2. Khao sat kha nang gay hai cua cac chung
nam Altemaria spp. odieu kien nha ludi
Bd tii till nghiem: Thi nghiem dugc bd hi hoan toan nglu nhien mot nhan to voi 4 lln lap lai (moi lap
lai tuong ling 10 cay liia/chau) va s6 nghiem thiic gom so chung nam dupc phan lap.
Phmmg phap tien hanh: Hat giong liia Jasmine 85 xac nhan sau khi dupc xu ly, ngam 24 gia, it 48 gia cho den khi nay mIm se dugc gieo vao cac chau dat chuan bi sin co duong kinh 25 cm. M6i chau trong 10 cay Ilia, tuoi nuoc va bon phan dam bao cho liia phat trien toL Cac chung nam Altemaria spp. dugc nuoi tren moi truong PDA, dat a di^u kien anh sang den huynh quang chieu xen ke 12 gio sang va 12 gia toi trong 14 ngay de hinh thanh bao tir. Sau khi nam hinh thanh bao tir, cho nuoc cat vo tning vao ffia petri, dimg lame da thanh trimg cao nhe tren be mat moi truong, luge qua vai luoc va thu huyen phii nam. Diing lame dem xac dinh mat so bao tii va pha loang huyen phii nam o mat so 2x10*̂ bao tu/ml. Tien hanh chung benh a thoi diem 72 ngay sau khi gieo. Lua dugc giir trong toi 12 giir truoc khi dugc chung b&nh. Bong lua dugc chiing benh vai huyen phii nam Altemaria spp. a nong do 2x10^ bao tit/ml, mdi chau phun 10 ml huyen phii nam sao cho tat ca cac bong Ilia uot deu. Sau khi chung benh, cac chau liia dugc dem di u benh o nhiet dp 25°C, am dp 95% trong toi a 24 gia. Sau khi u benh, cac chau liia dugc dat trong di&u kien anh sanh binh thuong a nha luoi co che mat de theo doi su phat trien cua bfenh.
Chi tieu theo dor. Lay chi tieu a 3, 5, 7, 9 va 11 ngay sau khi chiing benh nhan tao. Thu lay 1 bong liia/Iap lai va dem toan bo so hat liia/bong di u theo phuong phap Blotter (ISTA, 1985). Quan sat cac hat Ilia bi nhi6m benh duoi kinh soi noi va kinh hien vi quang hpc de xac dinh ty 16 hat liia bi nhiem benh lem lep hat do nam Altemaria spp. gay ra.
Ty le hat nhifem benh dugc tinh theo cong thiic:
TLHB (%) = [(So hat liia bi benh/Tong so hat tren bong liia) x 100].
2.2.3. Khao sat kha nang ddi khang cua cac chung xa khuan ddi vdi nam Altemaria sp. a diiu kien phong thinghiem
Bd tri thi nghiem. Thi nghiem dugc bd tri hoan toan ngau nhien mot nhan to voi 5 lln lap lai (1 dia petri/lap lai). Sd nghiem thuc gdm 7 chiing xa khuan (rG2.1. TG4.3, VL5.4, DT3.4, AG2.1, CT4.8, HG4.2) nhan tir phong thi nghiem benh cay (Bg mon Bao vd thuc vat, Khoa Nong nghiep, Trucmg Dai hpc Cln Tho) va ddi chiing.
NONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 - THANG 7/2020 85
KHOA HOC CdNG NGHE
Phuong phap tien hank Chiing nam Altemaria sp. gay hai nang nhat dupc nudi hong dia pehi vdi 10 ml mdi hudng PDA khoang 7 ngiy. Nhimg chung xa khuin dupc nudi ciy frong mdi hirdng MS hong 7 ngiy. xac dmh mat sd va chuyen ve huydn phu bio hi xa khuan la 10" ciu/ml. Dung dung cu due Id cd dudng kinh 5 mm da thanh himg due lay khoanh nam d ria mep tir dia nam ngudn rdi dat cac khoanh nim dd vio dia petri chiia 10 ml mdi trudng PDA, khoanh nim dat cich thinh dia 1 cm. Dat cic khoanh giiy thim (cd duimg kinh l i 5 mm) cd thim huyen phii xa khuin vdi mat sd W cfii/ml tir cic dng falcon; ddi vdi nghiem thiic ddi chiing cho giay tham (cd dudng kmh l i 5 mm) vao nude cit thanh himg. Sau dd. cac khoanh giiy tham nay duoc dat ddi dien vdi khoanh nam Altemaria sp. each thanh dia 1 cm. Cac dia petri cd dat khoanh nam. xa khuin vi nude ci t dupc dat d didu kien nhiet dp phdng.
Chi tieu theo dor. Do ban kinh vimg lie che d nghiem thuc cd xtt ly xa khuan va nghiem thiic ddi chiing d 7,9,11.13.15 ngdy sau bd tri.
Hieu suat ddi khing dupc tinh theo cdng thiic (MoayedivaeiK.2009):
Hidu suit ddi khang = |(G1-G2)/G11 x 100. Trong dd: Gl: Ban kinh vimg scri nam d nghiem
thiic dot chiing. G2: Ban kinh vung soi nam d nghiem thiic cd
xa khuin. 2.2.4. Khao sat kha nang tic che' su hinh thanh
bao ttinam Altemaria sp. cua cac chung xa khuan & dieu kien phdng tiii nghiem
Bd bi thi nghidm: Thi nghiem bd tri hoan toan ngiu nhien. mdt nhin td vdi 5 lin lap lai. Sd nghiem thiic l i 3 chung xa khuan cd hieu qua ddi khang cao vdi nim Altemaria sp. vi ddi chung.
Phuong phap tien hanh: Chuan hi nam Altemana sp. va cac chiing xa khuan tuong hr nhu trong thi nghiem d muc 2.2.3. Tien hinh thi nghiem bang cich cho 3 khoanh khuan ty d phin ria tan nim (cd dudng kinh 5 mm) vio binh tam giac chua 98 ml PDB + 2 ml huydn phii xa khuan 10* cfii/mL Bdng thdi cung cho 3 khoanh khuin ty d phan ria tan nim (cd dudng kinh 5 mm) vao binh tam giic chiia 98 nd PDB + 2 ml nude cat da duoc thanh ttiing. Bern cic hinh tam giic di lie vdi tdc dp 100 vdng/phut.
Chi tieu tiieo ddi: Quan sat va dem mat sd hao rir nam hinh thanh dudi kmh hien vi cua cac nghiem thuc a 1. 3. 5. 7. 9 va 11 ngiy sau nudi lac.
Hieu qua uc che su hinh thanh bao tu dupc tinh
theo cdng thiic: HQUC(%)»[(C-T)/ClxlOO. Trong dd: C: Mat sd hao hi hudi thinh d nghiem
thiic ddi chiing. T: Mat sd bio hi hmh thanh d nghiem thiic xu
lyxa khuan.
2.2.5 Khao sat kha nang tic che su moc mam cua bao tir nam Altemaria sp. ddi vdi huyen phu aia cac chiing xa khuan d dieu kien phdng thinghiem
Bd bri thi nghiem. Hoin toan ngiu nhien. mdt nhan td vdi 4 lan lap lai. Sd nghiem thiic gdm 3 chiing xa khuin cd hieu qui ddi khang cao vdt nam Altemaria sp. vi ddi chiing.
Phuong phap tien hanh: Chuan hi nim Altemaria sp. hrong hr nhu hong thi nghiem d muc 2.2. Chuan bi cic chung xa khuan hrong Ur nhu trong thi nghiem d muc 2.2.3. Thi nghiem dupc hdn hanh bang each nit 500 pi huyen phii xa khuan d mat sd 10̂ ctu/ml + 500 pi huydn phii nam Altemaria sp. 6-mat sd 2x10" bio tir/ml cho vao ong efipendorf. Ddng thin nit 500 pi nude cat vd hiing + 500 pi huyen phii bao tir nam Altemaria sp. d mat sd 2x10" bio hi/ml cho vio dng efipendorf. Bat cac dng efipendorf niy d nhidt dd 25"C.
Chi tieu theo rfo/l-Quan sat su moc mam ciia bao tu nam dudi kinh hien vi d 6. 9.12 va 24 gid sau xu ly.
Ty le mpc mim cua bao hi nam dupc tinh theo cdng thiic:
TLMM (%) = [ (Sd bao hr mpc mam/Tdng sd bio tir quan sit) X 100].
Hieu qua lic che dupc tinh theo cdng diiic: HQUC(%)-[(C-T)/ClxlOO. Trong dd: C: Ty le hao hi moc mam d nghiem
thiic dot chung (%).
T: Ty Id bio hi moc mam d nghiem thiic xu ly xa khuin (%).
2.3. Xuly s i lieu
Cic sd Ueu duoc xu ly tren phan mSm Microsoft Office Excel va phin tich bang phan mdm thdng ke MSTATC qua phep thu Duncan.
K^t qua phan lip cho tiiay 100% mlu liia benh lem lep hat tiiu hi ddng mdng deu bi nhidm nim Altemaria spp. vdi ty le nhiem benh khac nhau b "' ddng hi 40.0-55.(W (Bang 1). Didu nay cho thay ta sd xuat hien cua nim Altemana spp. (, MI, ', ..
NONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 - THANG 7/2020
KHOA HOC CONG NGHl
ngoai dong l i r i t cao (100%) vi chung nim Altemaria.CKl-TV (thu thap tii huyen Ciu Ke, tinh Tra Vinh) cd ty le hat hi nhidm li 55.0% va cao hon cd vdi cac chiing nim thu dupc d nhiing mpng khac.
PP-Ty le hat bi nhiSm (%) 50.0+5.16 48.0±8,64 55.0+10.0 54.0+8.30 49.0+8.87 45.0±7.57 52.0±5.67 40.0+5.67 53.0+8.87 46.0+7.66
Quan sat hinh thai duoi kinh soi noi ciia 10 chung nam Altemaria spp. tren hat bi nhifim benh deu cho thay sgi nlm min, ben chat, ban diu mau nau nhat sau do chuyen sang mau xam tring bao phu hat Ilia.
Quan sat duoi kinh hien vi b vat kinh 40X tren moi truong PDA tat ca cac chiing nam cung deu co hinh thai sgi nam giong nhau, sgi nam ciing co mau nau nhat, phan nhanh va co nhieu vach ngan.
6 mat tren dia petri, sgi nam khi sinh phat trien, moc tuong ddi sat moi truang, nhuy6n min, moc ben chat, hoi nho iSn khoi moi truong nuoi cay va co mau
xam tring hoi ung hong. 6 mat duoi dia petri, khuan lac mau nau den nau den, co nhi^u vong tron dong tam voi cac vong phia trong co mau den va nhat din ra phia ngoai, phia ngoai ria co mau tring mgc d6u nhau.
Bao tli nam thing, co nhieu te bao, co dang hinh chiiy mot dau to va thon nho dan ve dau kia, co 1 phan phu bg a 1 dau. Bao bi co vach day, co 3-5 vach ngan, da so co 4 vach ngan va thit eo lai tai vach ngan, te bao thii 2 va thti 3 thuong phuih to hon cac te bao con lai, kich thuoc bao gom ca phan pho bg 105.5-185,5 Hm x 11,5-17,6 nm.
Khuan lac ciia ca 10 chung nam Altemaria spp. tren moi trudng PDA phat tri^n tuong ddi cham voi tdc dp phat tri^n 6,24-9,87 mm/ngay. Duong kinh khuan lac cua cac chung nam Altemaria spp. 6 7 ngay sau nuoi cay (NSNC) co sir khac nhau dao dong tir 4,64-6,14 cm; trong do, chung nam Altemaria.CKl-TV la chung co duong kinh khuan lac lon nhat (6,14 cm) va 2 chiing nlm co duong kinh khuan lac thap nhat gan nhu nhau la Alteniaria.TB-AG (4,64 cm) va Altemaria,OU-CT (4,68 cm) (Bang 2).
Dua vao dac cac diem hinh thai cho thay cac chimg nam phan lap dugc thuoc chi Altemaria theo khoa phan loai cua Bamett va Hunter (1998). B6n canh do, khi so sanh cac dSc diem ve hinh dang va kich thuoc bao tu voi cac ket qua nghien ciiu ciia Mew va Gozales (2002), Nguyen Van Luc (2013), Trin Thi Thu Thuy (2011) thi cac chiing nam Altemana spp. rit gidng voi loai Altemaria padm'ckii.
Bang 2. Die dilm hmh thii cua cic chung nSm Altemaria spp. 6
Kha nang gay hai cua 10 chiing nam Altemaria spp. trong dieu kien nha luoi dugc danh gia thong qua t\' le (%) hat liia bi nhi^ni bfenh tren tdng sd hat
NONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 - THANG 7/2020 87
ciia bdng lua b cac thdi diem 3. 5, 7. 9, 11 ngiy sau chung hdnh (NSCB) (Bang 3).
^ a flidi diem 3 NSCB, tat ca 10 chung nam deu the hien kha nang gay bdnh vdi ty 16 hat hdnh dao ddng tir 17.1 - 33.7%. Til flidi diem 5 NSCB hd di, ty le hat bdnh Uep hic gia ting a cac chung nim. dao ddng til 17,2 - 37,9%; ddn thdi diem 11 NSCB, cd 7 chung nim giy hai frdn hat lua cd ty le benh cap tren 50% Ian lupt la Altemaria.CKl-TV, AltemariaSM.NL, Altemaria.lB-ST, Altemaria.CKZTV, Altemaria.TO-VL. Alteniaria.OM-CT, Altemaria.TB-ST: hpng dd chung nam Altemaria.CKl-TV gay hai hen hat vdi ty Id benh cao nhat (64,9%) va khac biet cd y nghia so vdi cic chiing nam cdn lai (Bang 3).
Ket qua thi nghidm cimg cho thiy trieu chiing giy hai tren hat cda 10 chtmg nim Altemaria spp.
(2013) sau khi dupc liy benh nhan tao vdi nim Altemaria padwickii\a vet henh bat diu hmh fliinh vdi cham nhd hmh mui kim, miu niu nhat. Bdn canh dd. kdt qua nay cung phii hpp vdi nghidn am cua Lau etal. (2012) hen hat lua, bio hi nam Altemaria padwickhhan dau xam nhidm chu yeu tan cdng qua cic chin long hen vd hat. sau dd nam tan cdng den cic te bao bieu bi xung quanh vd hat tao fliinh nhung ddm nau nhd cd dudng kuih khoing 1 mm. sau dd nhiing ddm nau nhd lan rdng ra bid'n vd hat tiiinh timg mang miu den hoac den sam. bien hat trd nen lep va lung.
Nhu vay, ket qua lay nhidm bdnh nhin tao hong didu kien nhi ludi da xic dinh dupc Altemaria.CKl-TV la chiing nam giy hai nang nhat tren hat cua gidng lua Jasmme 85.
tuong tu vdi ket qua nghien ciiu cua Nguydn Van Liic Bang 3. Ty Id hat bdnh do 10 chiing nim Altemaria spp. giy ra qua cic thdi dilm khao sit
Nghiem thuc
AltemariaTQ-NL Altemaria.mA-V\. Altemaria.CKl-TV Altemaria.CK2-TV AltemariaTT-AG AltemariaTS-AG Altemaria.OM-CT Altemaria.PB-CT Altemaria.TB-ST Altemaria.LB-Sr Miic y nghia F
CV(%)
Tyle hat henh (%) 3 NSCB 27,6abc 25.9abc 32.3ab 31.9ah 26.3ahc 22.5cd 29.7ahc 17.1d 33,7a 23,6 bed
Chi chii: Cac sd tiong cung mot cot dirac theo sau bdi mdt hoac nhidu chu cai gidng nhau thi khdng khac bidt qua phep kiem dinh Duncan: sd lieu chuyen ddi sang dang arcsm ^ (x) trudc khi phan tich thdng ke: **: Khac biet dmiic y nghia 1%: NSCB: ngay sau khi chung benh.
TV hong didu kien phdng thi nghiem d cac muc dp khic nhau va BKVUC giim dan tir thdi diem d 9 NSBT den 15 NSBT hi 2.6-16,0 mm; trong dd cd 3 chiing xa khuin tiie hien khi nang ddi khdng cao va khic biet cd y nghia ve mat flidng ke d mirc y nghia 1% so vdi cac chung xa khuan cdn lai d flidi diem 15 NSBT vdi BKVUC lan lupt li CT4.8, DT3.4 va TG2 1 vdi BKVUC lan luot la 23.0 mm. 7,0 ram va 5 0 dac biet chung xa khuan CT4.8 ludn cd BKVUC nhat qua cic thdi diem khio sit.
Kdt qua flii nghiem niy cd su hiong ddng vdi cic ket qua nghidn ciiu ciia Vd Duy Hoang (2019) d'
NONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 - THANG 7/2020
3.3. Kha nang ddi khing cua cic chiing xa khuin ddi vdi nim Altemaria.CKl-TV h-ong diiu kidn phdng Ihi nghidm
Kha nang ddi khing cua 7 chung xa khuan ddi vdi nam AItemaria.CKl-TV hong dieu kien phdng flii nghiem duoc danh gii thdng qua bin kmh vung lic che (BKVUC) va hidu suit ddi khang (HSDK).
Ket qua trong bang 4 cho fliiy BKVUC cua 7 chung xa khuin (AG2.1, CT4.8. HG4.2 BT3.4,TG4.3, TG2.1 va Vl.5.4) d cic thdi diem 9, 11, 13, 15 NSBT ddu cd khi ning ddi khang vdi nam Altemaria.CKl-
gia khi nang ddi khang cua 7 chung xa khuan (AG2.1, CT 4.8, DT3.4. VL5.4, HGl.l. HG4.2 vi TG2.1) ddi vdi nam Fusarium moniliforme gay benh Ilia von va Bien Thi Bich Chi (2019) dinh gia kha nang ddi khing cua 7 chiing xa khuan ddi vdi nam Curvularia sp. gay henh lem lep hat lua la ca 3 chung xa khuan CTi.S, TG2.1 va DT3.4 deu cd kha nang ddi khang manh va on dinh vol bin kinh vimg lie che lin lupt la CT4.8 (13,5 v i 15.5 mm). TG2.1 (5.0 v i 9,0 mm) va BT3.4 (5.25 vi 3.0 mm). Tuy nhien. BKVUC ciia chung xa khuan CT4.8 ddi vdi nam Altemaria.CKl-TV trong ket qua nghidn ciiu nay (23.0 mm) cao hon nhieu so voi cac nghien cuu ciia Vo Duy Hoing (2019) v i Bien Thi Bich Chi (2019) doi vdi nam Curvularia sp. va nam Fusarium monlUforme.
Bang 4. Bin kinh vimg lie chd cua 7 chiing xa khuin ddi vdi chung nam ^te/nanaCKl-TV qua cic thdi
di^m khao sit
Nghiem thuc
TG2.1
TG4.3
VL5.4
DT3.4
AG2.1
CT4.8
HG4.2
Miicy nghia F
CV(%)
Bin kinh vun^
9 NSBT
16.0h
14,6b
16,0b
15,8b
16,4b
25,6a
14,6b
.. 2,86
11 NSBT
11,8c
7,00e
15,6b
8,40d
11,2c
24,8a
8,00de
.. 3,48
' ire che (mm) 13
NSBT
7,80bc
5,00d
6,20cd 8,20b
6,00cd
23,6a
5,20d
.. 5,41
15 NSBT
5,00c
2,60d O.OOe
7,00b
3,00d
23,0a
3,00d
.. 9,30
Ghi chu: Cac so tiong cung mdt cdt duoc theo sau ben mdt hoac nhieu cho cai gidng nhau thi khdng khac biet qua phdp kiem dinh Duncan: sd lieu chuyen doi sang dang log (x-i-1) tivdc khi phan ti'ch tiidng ke: ": Khac biet a muc y nghia 1%: NSBT: ngay sau bd tif.
Ket qua hong bang 5 cho thiy 7 chung xa khuan d k cd hieu qua ddi khang vdi nam Altemaria.CKl-TV o cic miic dp khac nhau vi HSDK tang dan to thdi diem 9 NSBT den 15 NSBT; hong dd 3 chung xa khuan cd HSDK cao va khac biet cd y nghia so vdi cac chung xa khuan cdn lai cung la CT4.8, TG2.1 vi DT3.4 vdi HSDK lin lupt l i 57,0%. 32,5% vi 30,8%. Mat khac, mdt sd chiing xa khuin cd xu hudng giam kha nang ddi khang theo flidi gian thi nghiem (vi du
chung VL5.4) thdng qua BKVUC vi hieu suit ddi khing giam. Didu niy cd the giai thich l i do d diu thi nghiem, cac chung xa khuan sinh trudng vi phit trien nhanh nen kha nSng ddi khing cao, khi thdi gian thi nghiem cang vd sau, mdt sd chung xa khuan khdng cdn kha ning phat hien va ting mat sd (do mdi trudng sdng khdng thuin lpi, nim benh phit trien...) til dd lim suy giam kha nang ddi khang cua xa khuan. Tuy nhien. 3 chung CT4.8, TG2.1 vi DT3.4 vin duy tri kha nang ddi khang cao thdng qua BKVUC cao vi hieu suit ddi khang cao so vdi cac chimg xa khuan dung hong thi nghiem.
Bang 5. Hidu suit ddi khing cua 7 chung xa khuin ddi vdi nim Altemaria,CKl-TV qua cic thdi diim
khao sit
Nghiem thiic
TG2.1
TG4.3 VL5.4 DT3.4
AG2.1
CT4.8 HG4.2
Miic y nghia F
CV(%)
Hidu suit ddi khang (%)
9 NSBT
14.3b
lO.Sbcd 7.40cde 6,88de
ll,Obc 33,8a
4,75e
.. 10,7
11 NSBT
19,8b
12,1c 6,52d 10,5cd
15,6bc 45,7a
12,6c
.. 11,8
13 NSBT 27,8b
19,4bc 2,92d
22.3hc 18,1c
52.1a 24,8bc
.. 11,5
15 NSBT
32,5b
21,0c l,64d
30,8b 22,6c
57,0a 23.6c
*• 5.40
Ghi chu: Cac sd tiong cung mot cot duoc theo sau bdi mot hoac nhiiu chd cai gidng nhau thi khdng khac biet qua phep kiem dinh Duncan; sd lieu chuyen ddi sang dang arcsin ^(x) trudc khi pban tich thdngke; *: Khac biet & mdc y nghia 1%; NSBT: ngay sau bd tri.
So sanh vol ket qua nghien ciiu cua Vo Duy Hoang (2019) va Bien Thi Bich Chi (2019) thi ca 3 chiing xa khuan CT4.8, TG2.1 va DT3.4 deu co HSDK cao doi voi nam Curvularia sp. va nam Fusarium monilifonne lln lugt la 47,7 va 51,1%; 40,7 va 28,7%; 34,3 va 24,7%. Tuy nhien, HSDK cua chiing xa khuan CT4.8 ddi voi nam Altemana.CKl-TV trong k6t qua nghien ciiu nay (57,0%) cao hon so vm nam Curvulana sp. va nlm Fusarium moniliforme.
Tom lai, qua ket qua khao sat kha nang doi khang thong qua BKVUC va HSDK h-ong dieu kien phong thi nghiem da xac dinh duoc 3 chung xa khuan co hieu qua doi khang cao doi voi nam
N 6 N G NGHIEP V A PHAT TRIEN NONG THON - KY 2 - THANG 7/2020 89
KHOA HOG CONG NGHl
^femanaCKl-TV hong sd 7 chung xa khuan dupc thii nghiem lan lupt la CT4.8. TG2.1 va DT3.4; hong dd chiing xa khuin CT4.8 cd hien vong cao nhat
3.4. Kha ning lie chd su hmh thinh bio hi nam /4/feroanaCKl-TV c ia cac chiing xa khuin trong di& kidn phdng thi nghiftn
Ket qua hong hang 6 da cho thay 3 chiing xa khuan CT4.8, BT3.4 va TG2.1 cd kha nang uc chd su hinh fliinh bao hr nam ^fcraanaCKl-TV tii flidi diem 1 ngiy sau nudi lie (NSNL). Nhu viy. cd the chinh cic enzyme ngoai bio nhu chihnase. p-
glucanase cua 3 chung xa khuan CT4.8. TG2.1 vi DT3.4 da lam lie che su hmh ttianh bao hi nim ^te/i?ana.CKl-TV. Tuy nhien, log mat so bao hi ciia nim ^tentanaCKl-TV tang dan d thdi diem 1 NSNL ddn 11 NSNL to 0,28-1,02; die biet log mat sd bio hi ting nhanh d flidi diem 5 NSNL to 0,2W),39. Tuy nhien. kha nang iic che cua chung TG2.1 ddi vdi nim ^teroanaCKl-TV dat cao hon so vdi nim Fusarium moniliforme hong ket qua nghien cuu cua Vd Duy Hoing (2019).
Bang 6. Log mat so
Nghiem thiic
TG2.1 DT3.4
CT4.8 DC Miic y nghia F CV(%)
bio hi nim Altemaria.Cm.VI hinh thinh qua cic flidi di&n khao sit Log mat sd bao hi hmh thinh
INSNL 3.53h 3.19c 3.16c 4.17a
., 4.19
3 NSNL 3.63b 3,37c 3,42c
4,19a
.» 2,52
5 NSNL 3,92b 3,76c 3,73c 4,44a
•* 1,49
7 NSNL 4,05b 4,00b 3,87c 4,45a
" 0,68
9 NSNL 4,20h 4,22b 4,14c 4,46a
•* 0,67
11 NSNL 4,29b
4,21c 4,17c 4,45a
** 0,88
Ghi chu: Cac sd trong ciing mot cot duoc theo sau bdi mot hoac nhiiu chd cai gidng nhau thi khong khac biet qua phep kiim dinh Duncan; *: Khac biet dmuc y nghia 1%; NSNL ngay sau nuoi ldc.
K^t qua h-ong bang 7 da cho thly ca 3 chung xa khuan CT4.8, DT3.4 va TG2.1 co hieu qua lie ch^ su hinh thanh bao tu nam Altemaria.CYH-TV kha cao b thoi diem 1 NSNL tif 77,2-90,3% va hieu qua lie che bi t dau giam hr 3 NSNL d6n 11 NSNL; dac biet giam manh 6 thai diem 9 NSNL tir 16,1-22,3%. Trong do, 2
chung xa khuan CT4.8 va DT3.4 co hieu qua lie ch^ su hinh thanh bao tir ciia nlm Altemaria.CKl-T^ keo dai va dat ty le tir 41,947,8%. Ket qua nay cao hon so voi chung TG2.1 itc che su hinh thanh bao tic nam F. moniliforme cao nhat voi log mat so bao tic nam la 5,44 o thoi diem 9 ngay sau xir ly.
Bang 7. Hi^u qua lic ch^ su hinh thinh bao tu nam ^temaraaCKl-TV cua cic chiing x^ khuan qua cic th6i di^m khao sit
Nghiem thiic
TG2.1 DT3.4 CT4.8
Miic y nghia F CV(%)
Hieu qua lic che (%)
INSNL 77.2b 88,1a
90,3a
»» 4,34
3 NSNL 71,8b 84,0a
82,7a
** 5,64
5 NSNL 69,7b 78,6a 80,7a
** 5.44
7 NSNL 60.4b 64.8b 73.6a
** 2.90
9 NSNL 44.3ab 42.5b
52.2a
** 5.64
11 NSNL 30.4b
41.9ab
47.8a
** 10,1
Chi chu: Cac sd tiong ciing mdt cot duac theo sau bidt qua phep kiem dinh Duncan:': Sdheu chuyen ddi Khac biet dmucy nghia 1%; NSNL: ngay sau nudi lic.
Nghien cuu cua Trejo-Eshada et al. (1998) da chi ra rang mdt sd loii Sheptomyces cung cd kha ning Het cac enzyme pha huy vach te bio nam bdnh nhu chitinase. p-glucanase. Nghien ciiu cua Joo (2005) da cho fliiy xa khuin Stieptomyces halstedii AJ -7 hdt ra enzyme ngoai hao chitinase cd kha nang
bdi mdt hoac nhieu chu cai gidng nhau tiii khdng khac sang dang arcsm V (x) tivdc khi phin tich thdng ke- '•
lie chd su hmh fliinh bio to aia nim Fusarium oxyspomm. Ngoii ra. theo nghien cuu cua Schoenian e^ al. (2011) thi mdt so loai xa khi ' Sheptomyces cd khi nang tiet ra khang smh anhmycins (thudc nhdm urauchimycms) cd tic d ' lie che su dan ttnyen dien to d ty the trong qua trinh
90 NONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 - THANG 7/2020
ho hap gay lic che cac qua trinh smh ly, sinh hoa ciia t^ bao nam b§nh (trich din boi Sharma el al., 2014). Nhu vay, 3 chung xa khuan tri^n vong CT4.8, TG2.1 va DT3.4 con co them mot dac tinh doi khang voi nam Altemaria.CKl-TV la kha nang lic che su hinh thanh bao tir cua nlm.
3.5. Khi nang lie ch^ su mgc mam bao tii nam Altemaria sp. cua huy^n phii xa khuin trong di^u ki§n phong thi nghidm
K^t qua trong bang 8 cho thay ca 3 chung xa khuin CT4.8, TG2.1 va DT3.4 deu th^ hien kha nang lie che su moc mIm ciia nam Altemaria.CKl-TV a cac mirc dp khac nhau va ty 16 bao tu moc mIm tang dan qua cac thoi diem khao sat o 6, 9. 12 va 24 gio sau xu ly (GSXL); trong do, chiing xa khuin DT3.4 the hien kha nang lie che su moc mam som va cao hon doi voi nam Altemaria.CKl-TV so voi 2 chimg xa khuan con lai.
Bang 8. Ty Ife mgc mam aia bio tb nam Altemaria.CKl-TV qua cic thdi di^m khao sit
Nghiem thiic
TG2.1 DT3.4
CT4.8 DC Miic y nghia F CV(%)
Ty le bao to moc mam {%)
6 GSXL
16.0b 11.7c 16.8b 41.0a
* 5.91
9 GSXL 30.5b 14.8d 23.3c 50.7a
.. 3.91
12 GSXL 44.4b 29.2c 32.9c 60.2a
.. 3.55
24 GSXL 51,5b 39,3c 40,6c 69,0a
" 6,50
chimg CT4.8, TG2.1 va DT3.4 deu the hien kha nang lie ch^ su moc mam bao tu doi voi nam Pyricularia oryzae vbi hieu qua som o 6 GSXL vl keo dai den 24 GSXL. So dl, xa khuan co kha nang lie che su mgc mIm cua bao tu nam benh la do cic hop chit khang sinh, enzyme phan huy (chitinase, p-glucanase,...). Theo nghien cuu cua L& TuIn Anh (2016) thi cac chiing xa khuan CT4.8. TG2.1 va DT3.4 co kha nang tiet enzyme ^glucanase, tiet enzyme chitinase co kha nang lie che bao tir nlm P. oryzae mgc mIm. Do do, CO the chinh nhimg enzyme ngoai bao (chitinase, p-glucanase) co trong huyen phu cua cac chung xa khuan CT4.8, TG2.1 vl DT3.4 da co tac dong gay lie che su mgc mam ciia bao hr nam Altemaria.CK\-TN.
Tom lai, ca 3 chung TG2.1, DT3.4 va CT4.8 vira CO kha nang lic che su hinh thanh bao tir vira co khi nang ice che su moc mam doi voi nam Altemaria.CK\-TV.
Bang 9. Hi6u qua lie ch^ su mgc mIm ciia cic chiing xa khuan ddi vdi bio tu nlm Altemaria.CKl-TW qua
cic Ihdi di^m khao sit
Nghiem thiic
TG2.1 BT3.4 CT4.8 Miic y nghia F CV(%)
Hieu qua dc che (%)
6 GSXL 60.9ab 71.5a 59.0b
" 5.78
9 GSXL 39.8c 70,8a 54,0b
" 5.42
12 GSXL 26.2b 51.4a 45.2a
.. 6.06
24 GSXL 25,4b 43.2a 41,2a
* 12,3
Ghi chu: Cac sd tiong cung mdt cdt duoc tiieo sau bai mdt hoac nhieu chu cai gidng nhau till khong khac biet y nghia qua phep kiem dinh Duncan: sd lieu chuyen ddi sang dang arcsin V (x) tiirdc khi phan tich thdng ke; *'.• Khac biet a muc y nghia 1%: *: Khac biet a muc y nghia 5%: GSXL: gid sau xu ly.
Hieu qua uc che su moc mim cua cac chung xa khuin ddi vdi hao to' nam A/fcrnarra.CKl-TV dupc duy hi va kep dii td 6 GSXL den 24 GSXL; hieu qua lie che dat hieu qua kha cao hdn 50% d 6 GSXL va giam dan den 24 GSXL. hong dd 2 chung xa khuan DT3.4 vi CT4.8 the hidn ning lic che cao hon so vdi chung xa khuan TG2.1 (Bang 9).
Cac loii Sheptomyces duoc biet la cd kha ning lie che su moc mim cua bao to nam benh cay hdng (Walter va Crawford. 1995). Mdt nghien cuu cua Vd Thi My Kim (2016) da chi ra ring huyen phu cua cic
NONG NGHliP VA PHAT TRIEN NONG THON - KY 2 - THANG 7/2020
Ghi chu: Cac sd tiong ciing mot cot dupc theo sau bdi mot hoac nhieu cbd cai gidng nhau thi khong khac biet y nghia qua phep kiem dinh Duncan; sd lieu chuyen ddi sang dang arcsin \ (x) tivdc khi pban ti'ch tiidng ke; **: Khac biet d mm: y nghia 1%; *: Khac biet & muc y nghia 5%; GSXL: gid sau xuly.
4.KETLUAniVA0EniGHI
- Buoc diu xac dinh duoc 10 chiing nam phan lap tai 5 tinh DBSCL thuoc chi Altemaria va dugc ghi nhan co nhieu dac diem tuong ddng voi loai Altemana padwickii.
- Chung nam Altemaria.CK\-T\' (thu thap b huyen Clu Ke, tinh Tra Vinh) co kha nang gay benh lem lep hat liia nang nhlt trong so 10 chung nlm Altemaria spp. phan lap.
- Ba (03) chiing xa khuan CT4.8. DT3.4 va TG2.1 CO kha nang ddi khang cao doi vdi nam
91
KHOA HOC CdNG NGHE
^feraanaCKl-TV frong sd 7 chung xa khuan duoc thii nghiem lin lupt l i CT4.8. TG2.1 va DT3.4; frong dd chting xa khuan CT4.8 cd frien vpng cao nhat.
3.4. Kha ning lic chd su hinh fliinh bio hi nim AferaanaCKl-TV cua cic chung xa khuin frong dite kidn phdng thi nghidm
Kdt qua frong bang 6 da cho thiy 3 ehung xa khuan CT4.8. DT3.4 va TG2.1 cd kha nang iic che su hmh fliinh bao to nim Altemaria.CKl-TV to flidi didm 1 ngiy sau nudi lie (NSNL). Nhu vay. cd the chinh cic enzyme ngoai bao nhu chihnase. fr
glucanase cua 3 chung xa khuan CT4.8. TG2.1 vi BT3.4 da lim UK che su hinh flianh bao tu nim Altemaria.CKl-TV. Tuy nhien. log mat sd bao to cua nim Altemaria.CKl-TV tang din d ttidi diem 1 NSNL den 11 NSNL to 0.28-1,02; dac biet log mat sd bao to tang nhanh d thdi diem 5 NSNL to 0.25-0.39. Tuy nhien, kha nang uc che cua chung TG2.1 ddi vdi nim Altemaria.CKl-TV dat cao hon so vdi nim Fusarium moniliforme frong ket qua nghien ciiu cua Vd Duy Hoing (2019).
Bing 6. Log mit sd bio to nam Altemaria.CKl-TV hinh fliinh qua cic flidi dilm
Nghidm thiic
TG2.1 DT3.4 CT4.8 DC Miic y nghia F CV(%)
khao sit
Log mit sd bio to hinh thanh INSNL
3,53b 3,19c 3,16c
4,17a
** 4.19
3 NSNL 3.63b 3.37c 3,42c 4,19a
*• 2,52
5 NSNL 3,92h 3,76c 3,73c 4.44a
*• 1.49
7 NSNL 4.05b 4.00b 3.87c 4.45a
** 0,68
9 NSNL 4,20b 4.22b 4.14c 4.46a
.. 0.67
11 NSNL 4.29b 4.21c
4.17c 4,45a
»» 0,88
Ghi chu: Cac SO tiong cung mot cot duoc theo sau bdi mdt ho0c nhieu chu cai gidng nhau thi khdng khac biet qua phep Idem dinh Duncan; *: Khac biet dmucy nghia 1%; NSNL: ngay sau nuoi ldc.
Ket qua trong bang 7 da cho thly ca 3 chung xa khuan CT4.8, E)T3.4 va TG2.1 co hieu qua iic che su hinh thanh bao tu nam .^ten7a/7^.CKl-TY kha cao o thoi di^m 1 NSNL tic 77,2-90,3% va hieu qua lie ch^ bi t diu giam tir 3 NSNL den 11 NSNL; dac biet giam manh o thin diem 9 NSNL tir 16,1-22,3%. Trong do, 2
Bang 7. Hi^u qui iic ch^ str hinh thanh bio tu nlm Altemaria.CKl-TW cua cac chiing xa khuan qua cic th6i di^m khao sat
chiing xa khuin CT4.8 va DT3.4 co hieu qua lie che sir hinh thinh bio tir cua nam Altemaria.CKl-TV keo dai va dat ty le tii 41,9-47,8%. Ket qua nay cao hon so vol chung TG2.1 iic che su hinh Uianh bao tir nam F. moniliforme cao nhat voi log mat so bao tir nam 11 5,44 o thoi diem 9 ngay sau xu ly.
Nghiem thiic
TG2.1 DT3.4
CT4.8 Muc y nghia F
CV(%)
Hieu qua uc che (%)
INSNL 77.2b 88.1a 90.3a
** 4.34
3 NSNL 71,8b 84,0a
82,7a
** 5,64
5 NSNL 69,7b 78,6a 80,7a
** 5,44
7 NSNL 60,4b 64,8b
73,6a
** 2,90
9 NSNL 44,3ab 42,5b
52,2a
** 5,64
11 NSNL 30,4b
41,9ab
r 47,8a
»* 10,1
Ghi chu: Cac sd tiong cung mdt cdt duac tiieo sau bdi mdt hoac nhieu chu cai gidng nhau thi khdng khac biet qua phep kiem dinh Duncan:': Sdheu chuyen ddi sang dang arcsm V (x) tiirdc khi phan ti'ch tiidng kd- '• Khac biet d mtic y nghia 1%: NSNL: ngay sau nudi ISc.
Nghien cuu cua Trejo-Esfrada et al. (1998) da " ' '̂ ^d su hinh thanh bao to cua nim Fusarium chi ra r ing mdt sd loai Sheptomyces ciing cd kha o^spomm. Ngoai ra, theo nghien cuu cua nang het cac enzyme phi huy vich te bio nam benh Schoenian et al (2011) flii mdt sd loai xa khuan nhu chitinase, ji-glucanase. Nghien cuu cua Joo Sheptomyces co kha nang hdt ra khang sinh (2005) da cho fliiy xa khuin Stieptomyces halstedu anhmycins (Uiupc nhcm miiuchimycms) cd tic dcng AJ -7 tidt ra enzyme ngoai bio chihnase cd kha nang •« *<= ^V dan fruyen dien tu d ty did trung qua tnnh
90 NONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 - THANG 7/2020
KHOA HOC CONG NGHE
ho hap giy uc ch^ cac qui trinh sinh ly, sinh hoa cua t^ bio nam bfenh (trich din boi Sharma el al, 2014). Nhu vly, 3 chung xa khuan tri^n vgng CT4.8, TG2.1 va DT3.4 con co them mot dac tinh doi khang voi nlm Altemaria.CKl-TV la kha nang iic che su hinh thinh bio tu cua nam.
3.5. Khi nang uc ch^ su mgc mim bao tu n ^ Altemaria sp. cua huy^n phii x^ khuan trong di^u ki$n phdng thi nghidm
Ket qua trong bang 8 cho thly ca 3 chiing xa khuan CT4.8, TG2.1 va DT3.4 deu thg hien kha nang lie chg su mgc mam cua nam Altemaria.CK\-TV 6 cac miic dp khac nhau vl ty le bio tii mgc mam tang din qua cac thoi diem khao sat b 6, 9, 12 va 24 gio sau xu ly (GSXL); trong do, chiing xa khuan DT3.4 the hifen kha nang lie che su mgc mim som va cao hon doi vod nam Altemaria.CKl-TV so vdi 2 chung xa khuan con lai.
Bing 8. Tf 1§ mgc mim cua bio tii nam Altemaria.CKlTS qua cic th6i dilm khao sit
Nghidm thiic
TG2.1 DT3.4 CT4.8 DC
Muc y nghia F CV(%)
Ty Id bio to moc mam (%) 6
GSXL 16.0b 11,7c 16,8b
41,0a
* 5.91
9 GSXL 30.5b 14,8d 23,3c 50,7a
.. 3,91
12 GSXL 44,4b 29,2c 32,9c 60,2a
.. 3,55
24 GSXL 51,5b 39,3c 40,6c 69,0a
.. 6.50
chimg CT4.8, TG2.1 va DT3.4 dfeu the hien kha nang lie che su mgc mim bao tii doi voi nam Pyricularia oryzae voi hieu qua sdm o 6 GSXL va keo dai den 24 GSXL. So dl, xa khuan co kha nang uc chg su mgc mam cua bao tic nam benh la do cac hop chat khing sinh, enzyme phan huy (chitmase, p-glucanase,...). Theo nghien cihi cua Le TuIn Anh (2016) thi cac chiing xa khuan CT4.8, TG2.1 va DT3.4 co kha nang tiet enzyme p-glucanase, tiet enzyme chitinase cd kha nang uc che bao tu nlm P. oryzae moc mim. Do do, CO the chinh nhung enzyme ngoai bao (chitinase, p-glucanase) co trong huyen phii cua cac chung xa khuan CT4.8, TG2.1 va DT3.4 da co tac dgng gay iic che su mgc mam ciia bao tir nam Altemaria.CK\TN.
Tom lai, ca 3 chiing TG2.1, DT3.4 va CT4.8 vira CO kha nang lie che su hinh thanh bio tir vira cd kha nang iic che su mgc mam ddi voi nam Altemaria.CK\-TV.
Bang 9. Hifiu qua iic chi su mgc mim ciia cic chung xa khuan doi v6i bio tu nlm Altemaria.CKX^W qua
cic th6i dilm khao sit
Nghidm thirc
TG2.1 DT3.4 CT4.8 Miic y nghia F CV(%)
Hidu qua lie che (%) 6
GSXL 60.9ab 71.5a 59.0b
.. 5.78
9 GSXL 39.8c 70.8a 54.0b
.. 5.42
12 GSXL 26.2b 51,4a 45.2a
„
6.06
24 GSXL 25.4b 43,2a 41,2a
* 12,3
Ghi chu: Cac so tiong cung mot cdt duoc theo sau bdi mdt hoac nhieu chu cai gidng nhau thi khdng khac biet y nghia qua phep Idem dinh Duncan; sd litu chuydn doi sang dang arcsm V (x) trudc khi phan tich thdng ke; **: Khac biet & mtic y nghia 1%; *: Khac biet dmucy nghia 5%; GSXL: gid sau xuly.
Hieu qui lie che su mpc mam cda cic chung xa khuan ddi vdi bao to nam Altemaria.CKl-TV dupc duy hi vi keo dii to 6 GSXL den 24 GSXL; hidu qua lie che dat hieu qua kha cao frdn 50% d 6 GSXL va giam dan den 24 GSXL, frong dd 2 chung xa khuan DT3.4 vi (jr4.8 flie hien nang itc chd cao hon so vdi chung xa khuan TG2.1 (Bang 9).
Cac loii Sheptomyces dupc biet la cd kha nang lie che su mpc mam cua bao to nim bdnh ciy frdng (Walter va Crawford. 1995). Mdt nghien cim cua Vd Thi My Kim (2016) da chi ra r ing huydn phii cua cdc
NONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 - THANG 7/2020
Ghi chii: Cac sd tiong cung mdt cdt duoc theo sau bdi mot hoac nhiiu chd cai gidng nhau thi khdng khac biet y ngbia qua phep kiem dinh Duncan; sd lieu chuyen ddi sang dang arcsin V (x) trudc khi phan ti'ch thdng ke; **: Khac biet o muc y nghia 196; *: Khac biet & muc y nghia 5%; GSXL: gid sau xuly.
4. i(FT LUAN VADE NGHI
- Budc diu xac dinh duoc 10 chung nlm phan lap tai 5 tinh DBSCL thuoc chi Altemaria vl dug^ ghi nhan co nhieu dac diem tuong d6ng voi loai Altemaria padwickii
- Chimg nam Altemaria.CKl-TW (thu thap b huyen Clu Ke, tinh Tra Vmh) co khi nang gay benh lem lep hat lua nang nhat frong s6 10 chung nlm Altemaria spp. phan lap.
- Ba (03) chung xa khuan CT4.8, DT3.4 va TG2.1 cd kha nang ddi khang cao doi voi nlm
91
KHOA HOC CdNG NGHl
^femanaCKl-TV flidng qua khao sat ban kinh vimg lie chd ldn, hidu suit ddi khing cao, khi nang tie che su hinh thinh bio to cao vi kha ning iic che su mpc mim cua bao to nim cao frong dieu kidn phdng thi nghiem.
- De nghi tiep tuc dinh danh den loai ddi vdi 10 chung nam phin lip tai 5 tinh DBSCL vi dinh gia kha nang phdng til cua 3 chung xa khuan CT4.8. DT3.4 vi TG2.1 ddi vdi hdnh lem lep hat lua do nim Altemaria sp. giy ra frong didu kidn nha ludi.
TAIUEUIHAMKIUO
1. Bamett. H. L and B. B. Hunter, 1998. niusfrated Genera of Imperfect Fungi. 4* Edihon. The American phytopathological society, Mmnesota, USA. 218 pp.
2. Bien Thi Bich Chi. 2019. Dinh gii kh i nang phdng tri cua xa khuin ddi vdi henh lem lep hat frdn lua nam Curvularia sp. giy ra. Luan van thac si nginh Bao ve thuc vat. Dai hpc Can Tho. Can Tho. 66 frang.
3. Burgess. L. W.. T. E. Knight. L. Tesoriero and P. T. Hien, 2008. Diagnostic manual for plant diseases m Vietoam. Ausfrahan Cenfre for Intemational Agricultoral Research. Canberra. Ausfraha. 210 pp.
4. ISTA-lntemahonal Seed Testmg Associahon. 1985. Intemational Seed Testing Association mle book. Seed Science and Technology, 13(2):299-520.
5. Joo, G. J.. 2005. Purification and characterization of an exfracellular chitinase from the antifungal bioconfrol agent Stieptomyces halstedh. Biotechnology Letters. 27:1483-1486.
6. Lau. K. H and J. E. Sheridan. 2012. Mycoflora of rice {Oryza sativa L.) seed in New Zealand. New Zealand Joumal of Agricultural Research, 183(5): 237 -250.
7. Le Minh Tudng va Ngd Thi Kun Ngin. 2014. Phan lap v i dinh gii kha ning ddi khang cua cic chimg xa khuin ddi vdi nam Rhizoctonia solanlKiihn gay benh ddm vin tien lua. Tap chi Khoa hoc -Tnrdng Dai hoc Can Tho, sd 4:113-119.
8. Le Mmh Tudng vi Trin Thi Thu Em. 2014. Khao sat kha ning ddi khang cua cic chung xa khuan ddi vdi nam Pyricularia oryzae giy benh dao dn hai Ida. Tap chi Khoa hoc - Tnrdng Dai hoc Can Thd, sd 4:120-126.
9. Le Mmh Tudng. Nguydn Thi My Ngin, 2015. Khio sat kha ning phdng frir cua xa khuan ddi vol hdnh bac la hai lua. Tap chi Bio vd fliuc vat. 6:3946.
10. Le Tuan Anh. 2016. Khao sit mdt sd dac tinh cua 8 chung xa khuan cd Wen vpng frong quin ly benh chiy la Ida do nim Pyricularia oryzae gay ra. Luan vin tdt nghiep dai hpc. Khoa Ndng nghidp va Sudi hpc ling dung. Dai hpc Cin Tho. Cin Tha.
11. Mew. T. W and P. Gonzales, 2002. A handbook of rice seedbome fimgi. International Rice Research histitote. Los Banos. Phihppmes. 83pp.
12. Moayedi G. and R. Mostowflzadeh-ghalamfarsa, 2009. Anfcigonistic Activities of Trichoderma spp. on Phytophfliora Root Rot of Sugar Beet, han Agricultoral Research 28(2) 21-38.
13. Nguydn Van Luc. 2013. Xic dmh tiiinh phin nim giy hai fren hat cua bdn gidng Ida tai tinh Sdc Trang va dinh gia hieu qua cua mdt sd loai thudc hda hoc frong didu kien nha ludi. Luin van tdt nghidp thac si nganh Bio vd thuc viL Dai hpc Cin Tho. Can Tho. 94 frang.
14. Notteghem J. L . Roux-Cuvelier M.. Andre F., Roumen E, 1995. Rice diseases in the Camargue (France). Cahiers Options Meditenaneennes, 15:41-44.
15. Ou, S. H.. 1985. Rice disease. 2" Edition. Common Wealth Mycological Institote. Kew Surrey. England. 380 pp.
16. Palaniyandi. S. A.. S. H. Yang. L. Zhang and J. W. Suh. 2013. Effects of actmobacteria on plant disease suppression and growth promotion. Apphed Microbiology and Biotechnology,°il-.yoll-%'^.
17. Pitt, J. I., and A. D. Hockmg. 2009. Fungi and Food Spodage. 3"" Edition. Springer Science plus Business Media, New York, NY 10013, USA 524 pp.
18. Sharmar, M., P. Dangi and M. Choudhary. 2014. Achnomycetes: source, identification, and theu applications. Intemational Joumal of Current Microbiology and AppUed Sciences. 3(2): 801 - 832
19. Trin Thi Thu Thuy. 2011. Xac dinh nim giy benh lem lep hat lua tai ddng bang sdng Cuu Long Tap chi Khoa hoc - Trudng Dai hoc Cin Tho sd 17a:155-163.
20. Tran Van Hai. 2005. Giao hnnh hda bao " fliuc vat Trudng Dai hpc Can Tho. Cin Tho 364 frang.
92 NONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 - THANG 7/2020
KHOA HOC CONG NGHE
21. Trejo-Esfrada, S. R. A Paszczynski and D. L. Cim Long. Tap chi Phat tiien va Hdi nhap, sd 17:73-Crawford. 1998. Antibiotics and enzymes produced 77.
1,1 <he Uocontsol agent Stieptiimycesviolaceusniger oj i r -TI . . . . - 1 ^ n„,r in.- .»,u- -YCED-9. Joumal of Industiial Microbiology & , . 24-Vo Thi My I ^ . 2016. Khao sat kha nang gay fti,(edii,o/c«7.21:81-90. ha. cua chmig nam/>77c</&7a<,yy^ae gay henh chay
la lua vung dat nggt va buoc diu nghidn cuu bi&n 22. Vd Duy Hoang, 2019. Danh gia kha nang phlp phdng hi. Luan van tdt nghiep Dai hoc. Khoa
phong hi cua xa khuan doi voi nam Fusarium Nong nghiep va Sinh hgc ling dung. Dai hgc Cln moniliforme Sheldon gay benh liia von. Luan van tdt Tho. Cln Tho. nghiep thac si nglnh Bao v6 thuc vat. Dai hgc Can Tho. Cln Tho. 99 frang.
25. Walter, M. Y. and D. L. Crawford, 1995. Characterization of Stieptomyces lydicus WYEC108
23. Vd Khlc Huy, 2014. Nang cao siic canh franh as a potential bioconfrol agent against fungal root vl gii tri xuat khau gao cua cac tinh dong bang song and seed rots. Appl Envton. Microbiol 61: 3119 -
3128.
EVALUATION OF BIOCONTROL ABILnY OF ACTINOMYCETES AGAINST^tenianasp. CAUSING RICE GRAIN DISCOLORATION DISEASE
Ly Hung ,̂ Le Minh Tuong^
^Masters student in Plant protection, Can Tho University
^College of Agriculture, Can Tho University
Summary
The study was carried out to find out the pathogenicity of Altemaria sp. causing the most serious damage for nee grain discoloration disease and tlie isolated actinomycetes strains having high antagonistic ability against Altemaria sp. under laboratory and nethouse conditions. For experiment investigating the pathogenicity of Altemaria spp. fungal strains. It was arranged following to a completely randomized design with 10 freatments (10 strains of Altemaria spp. was collected and isolated in 5 provinces of Can Tho, An Giang, Tra Vinh, Vinh Long and Soc Trang) and 4 replications under nethouse conditions. The results indicated that among of the 10 isolated fungal strains, Altemaria.CKl-TV (collected from rice fields in Cau Ke district, Tra Vinh province) was the most pathogenicity with 64.9% rate of infected grain at 11 days after inoculation. For experiment investigating the antagonistic ability of actinomycetes strams against Alternaria sp. also arranged followuig to a completely randomized design with 7 treatments (TG2.1, TG4.3, YL5.4, DT3.4, AG2.1, CT4.8. HG4.2) and 5 replications under laboratory condiUons. The results showed that 3 isolates CT4.8, DT3.4 and TG2.1 was the highly antagonistic ability against Altemaria.CKl-TV with radiuses of inhibition zones reached 23.00 mm; 7.00 mm; 5.00 mm and antagonistic efficiency was 57.0%, 30.81% and 32.5%, respectively, at 15 days after the designed experiment. Beside, invesUgaUon of the inhibitory ability of 3 achnomycetes isolates, CT4.8, DT3.4 andTG2.1 for the formation and germination oi Altemaria.CKl-TV spores were examined with 5 replications under laboratory conditions. The results found that 3 actinomycetes isolates, CT4.8. DT3.4 and TG2.1 showed high inhibitory effect of spore formation was 47.8%; 41.9%; 30.4% at 11 days after testing and high inhibitory effect of spore germination was 42.2%; 43.2%; 25.4% at 24 hours after treatinent, respectively. Keywords: Actinomycetes. Altemaria sp.. biological control, grain discoloration disease.
Ngudi phan bien: GS.TS. Nguyen Van Tuat
Ngly nhin bii: 10/3/2020
Ngly thang qua phan hitm 10/4/2020
Ngay duy^t ding: 17/4/2020
NONG NGHIEP VA PHAT TRIEN NONG THON - KY 2 - THANG 7/2020 93
