PHONG TRU BENH DOM VAN HAI BAP

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PHONG TRU BENH DOM VAN HAI BAP

t ThS.TRAN V A N H I ^ N - Vien lua DBSCL

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enh ddm v i n la mdt loai benh kha pho bien tren eac eanh ddng trong bap. Tac nhan gay benh la n i m Rhizoctonia solani Kiihn. Ngoai bap ra thi cdn ed nhieu cay ki chCi khac nhu lua, ca chua, khoai tay, thuoc la, dau phdng, dau do, bdng vai, eai bap, xa lach v.v... Benh ed nhilu trieu ehung khac nhau nhu thoi den r l , Id co r l , thdi gde than, khd v i n , thoi la tuy theo loai eay va giai doan sinh trudng eua eay. Thdi ky eay eon benh gay hai d re lam ed re ung nude nau den, cay do rap ggi la benh Id eo r l (ea ehua, thudc la vudn uam, dau dd...). Tren b i p , benh hai tren be, philn la, than va b i p tao ra nhieu v i t Idn loang

lo, ddm v i n da ho, hinh dang b i t ky nhu hinh dam may.

Vet benh lan tCr la phia dudi gdc len bap, cd, lam eay tan lui, b i p thdi, gay ton t h i t Idn tren eae gidng b i p (bap lai, bap n i p , b i p nggt).

Nam Rhizoctonia eo nhilu ehung khae nhau.

Chung cd dang hach tuang ddi Idn, kieh thudc tu 1,5-2,5 mm, m i u nau, khong ddng d i u , tde do tang trudng eua ehung kha nhanh (30mm/

ngay) trong mdi trudng nudi ely, d nhiet do eao 28-300C.

Cae ngudn n i m tren b i p ed the lay benh cheo tren lua va nguge lai.

Tren ddng rugng, benh khd v i n hai b i p xult hien quanh nam, mua mua benh phat trien manh va lay lan

Riy bap.

nhanh han mua khd. Benh thudng phat sinh vao thdi ky 30 ngay sau khi trdng va phat trien manh tang d i n cho tdi thai ky tro ed, ra b i p thu hoaeh. Benh nang se lam cae la tan lui, thdi than, hdng b i p va dan den nang suit bi anh hudng nghiem trgng. Vdi eae giong nhiem thi ty le benh dat tdi 90-95%. Cac y l u to mdi trudng nhu c h l do mua, do I m khdng khi, nhiet do va cac y l u to ky thuat nhu thdi vy, c h l do tudi, muc dp bdn phan dam, mat do gieo trdng d i u cd anh hudng r i t lan den mue do nhilm benh cua eay bip.Nhu'ng rudng trdng dly, nhieu cd dai, bit bung, khdng thong thoang. NhCrng rudng bdn khdng bdn qua nhilu phan dam lam cho cay b i p tdt ldp, y l u dt. NhCrng rudng trong b i p lien tue nhieu vu, nhieu nam, hoae trdng tren nhCrng ehan d i t trdng Ida vy trude da bi benh khd v i n gay hai nhilu... thudng la nhO-ng rudng de bj benh khd v i n gay hai han cae rudng khae.

Phdng trj benh:

De han c h l tae hai eua benh d i n muc t h i p nhlt, c i n ap dyng k i t hgp nhieu bien phap ngay t u d i u vu. Sau day la mdt so bien phap chinh:

- Do benh truyen tu vu trude sang vy sau chu yeu tu

•. li I tMA i L'l HI Mil! 1^! Amrffflmgc^! \m la i mmsi^^^ms) m

O THANH TUU KHOA HOC C Q N G NGHfi

cac hach nim t i n tai tren d i t ruong va cac sgi nim tren cac la bj benh tu vy trudc cdn sdt lai tren rugng, vi t h i sau khi thu hoach phai thu gom sach than la, phai khd roi ddt. Cd the bam nudc len rugng ngam 3-5 ngay d l diet hach nim trong dit. O l kho rdi cay, bua, xdi d i t ky de chon vui hach nim, han chl sue song cua ehung.

- Gieo trdng bip vdi mat do hgp ly, vy he thu nen trdng thua (80x20em), tfa djnh cay sdm, lam sach cd dai trong rugng de rugng ludn thdng thoang, giam bdt am do trong rugng.

- Bdn can doi va hgp ly giCi-a dam, lan va kali, khdng bdn qua nhieu phan dam, de cay bap sinh trudng khde han c h l benh xam nhiem va cd SCPC chong da vdi benh tdt ban.

- Trong trudng hgp ap lye benh qua manh thi nen thay vy bip bing mgt loai cay trong khac khdng nhiim benh dim van nhy hanh, tdi, dt hoac rau muong, rau cin.

- Su dyng thudc hda hge de diet benh nhu: Validacin 3L; Validan 3DD hoac 5DD;

Vivadamy 3DD hoac 5DD;

5BHN; TSM 70WP; Folieur 250EW; Cozol 250EC; Rovral 50WP de phun xjt. Cin phun luc trdi kho rao, it gid. Phun theo lieu khuyin cao, cin phun lln 2 each lln thu nhlt 15 ngay vi benh cd kha nang hoi phyc./.

NGUA BENH TifeU

t BS. PHAM VAN THAN Tiheo; http://www. suckhoedoisong. vn

S

au bao lyt, mdi trudng bj d nhilm, nguy ca xay ra eae loai djeh benh la rit Idn, dac biet la cae benh tieu chay. Cung vdi bien phap clp bach la xu' ly mdi trudng bj d nhilm, eung elp nudc saeh eho nhan dan cua eac dja phuang vung bao lu.

Bai vilt sau day se giup ban dgc cd nhij'ng hilu bilt de phdng chong cac benh tieu ehay do ta, ly.

Vi sao trong moi triro'ng sau bao lut de mac benh tieu chay?

Tai vung bao lyt, cac cdng trinh ve sinh, cong ranh bj ngap trong nudc nen cac chit thai eua ngudi va gia sue, xac dgng thyc vat hda vao nudc gay d nhilm nang cho mdi trudng nudc, dit va do vat chim trong nudc khien mim benh rit d l lan nhilm vao thuc an, nudc udng gay benh cho mgi ngudi dan. Han nu'a, sau bao lu, viec cung clp luang thyc va thyc phim bj han chl, nhilu dja phuang cdn bj cd lap bdi nudc lyt, chua ed dilu kien thyc hien an chin, uong sdi. Vi vay, hai loai benh tieu chay hay gap nhlt sau bao lyt la ta va ly.

Bai vilt nay chi d l cap ro viec phdng chong ta va ly.

Dac diem cua vi khuan

gay benh ta ly

Kha nang t i n tai cua vi khuan: trong nudc va thuc an, nhlt la d nhiet do lanh, phly khuin ta (PKT) cd the sdng dugc tCr vai ngay din 2-3 tuin. PKT cd the tdn tai nhilu nam trong cac dgng vat than mim d vung ven bien, nhung d l bj diet bdi nhiet do 80°C trong 5 phut, bdi hda chit cloramin B 10% va bdi mdi trudng axit; tryc khuan Shigella gay benh ly ton tai trong nudc nggt, rau song, thCpc an tir 7-10 ngay d nhiet do phdng; d quan ao nhiim ban va trong dat 6-7 tuan, nhung bj diet nhanh trong nudc sdi, dudi anh ning mgt trdi va cac thudc khu khuan thdng thudng. Tren thyc te hiu hit cac vi khuan gay tieu chay clp deu bj diet bdi nudc sdi 100°C va cac hda chat khu khuIn thdng thudng.

Bleu hien lam sang Benh ta the cap tinh dien hinh, muc dd nang cd cac trieu chung: dOt ngpt tieu chay dO' doi. Ban dau phan cd the it, set, sau phan Idng, toan nuac, mau tring due nhy nudc vo gao cd lin nhu'ng hat trang Ion nhin, mui tanh. Ogi tien nhieu lan, so lugng den hang chgc lit mgt ngay. Bgnh nhan d i non,

m

*yAU!IAIiLy!».LI.^^