Thaum cov ntsiab lus hlau ib kilogram ntawm cov khoom qhuav hauv cov nroj tsuag tsawg dua 60 mg, cov tsos mob tsis txaus tuaj yeem tshwm sim. Hauv cov mob me me, cov nplooj me me tshwm sim daj lossis daj daj, thiab cov leeg poob chlorosis. Cov tsos mob ua ntej ntawm ntug ntawm nplooj mus rau cov hlab ntsha tseem ceeb, thiab cov nplooj qub yog qhov qub; Nyob rau hauv cov xwm txheej hnyav, cov tub ntxhais hluas nplooj ua ntej thiab tom qab ntawd cov nplooj qub, kom tag nrho cov nplooj ntawm cov ceg thiab tendrils poob ntsuab thiab daj, thiab txawm tias cov leeg poob ntsuab thiab daj lossis albino. Cov nplooj ua nyias thiab yooj yim poob tawm; cov txiv hmab txiv ntoo yog me me thiab tawv, thiab tev yog ntxhib.
Txoj kev tiv thaiv:
① Ntxiv acidic chiv, xws li ammonium sulfate, ammonium nitrate, peat av, distiller cov nplej, vinegar nplej, thiab organic chiv, mus rau alkaline av nyob rau hauv sab qaum teb kom txo cov pH ntawm cov av thiab tso hlau los ntawm cov av;
② Txau ferric ammonium sulfate ntawm qhov concentration ntawm {{0}}.3 feem pua rau 0.5 feem pua, thiab tshuaj tsuag 3 mus rau 5 zaug ntawm 10 hnub. Kev siv av ntawm ferrous sulfate, cov tshuaj siv yog 10 kg / ha.
