Indlela yokwenza kunye nophuhliso lwe-glyphosate

I-Glyphosate luhlobo lwe-organic phosphine herbicide ene-ebroad spectrum etshabalalisayo. I-Glyphosate ikakhulu ithatha iziphumo ngokuthintela i-biosynthesis ye-amino acid enuka kamnandi, eyile biosynthesis ye-phenylalanine, i-tryptophan kunye ne-tyrosine ngendlela ye-shikimic acid. Ine-inhibitory effect kwi-5-enolpyruvylshikimate-3-phosphate synthase (EPSP synthase), enokubangela ukuguqulwa phakathi kwe-shikimate-3-phosphate kunye ne-5-enolpyruvate phosphate kwi-5-enolpyruvylshikimate-3-phosphate (EPSP), ngoko i-glyphosate iphazamise. kunye nale biosynthesis yokusabela kwe-enzymatic, okukhokelela ekuqokeleleni kwe-shikimic acid kwi-vivo. Ukongeza, i-glyphosate inokucinezela ezinye iintlobo ze-enzymes zezityalo kunye nomsebenzi we-enzyme yezilwanyana. I-metabolism ye-glyphosate kwizityalo eziphezulu icotha kakhulu kwaye ihlolwe ukuba i-metabolite yayo i-aminomethylphosphonic acid kunye ne-methyl amino acetic acid. Ngenxa yokusebenza okuphezulu, ukuthotywa okucothayo, kunye netyhefu yezityalo ephezulu ye-glyphosate kumzimba wezityalo, i-glyphosate ithathwa njengeyona ndlela ifanelekileyo yokulawula imichiza yokutshabalalisa ukhula. kunye nesiphumo esihle sokukhula, ngakumbi kwindawo enkulu yokulima izityalo ze-glyphosate ezinyamezelayo, iye yaba yeyona nto isetyenziswa kakhulu emhlabeni.

Ngokutsho kovavanyo lwe-PMRA, i-glyphosate ayinayo i-genotoxicity kwaye ayinakwenzeka ukuba ibangele umngcipheko womhlaza ebantwini. Akukho mngcipheko kwimpilo yomntu okulindelekileyo ngokuvavanywa kokutya (ukutya kunye namanzi) ezinxulumene nokusetyenziswa kwe-glyphosate; Landela imiyalelo yeleyibhile, kwaye akukho mfuneko yakukhathazeka malunga nohlobo lomsebenzi usebenzisa i-glyphosate okanye umngcipheko kubahlali. Akukho mngcipheko wokusingqongileyo ulindelekileyo xa usetyenziswa ngokuhambelana neleyibhile ehlaziyiweyo, kodwa isithinteli sokutshiza siyafuneka ukunciphisa umngcipheko onokubakho wokutshiza kwiintlobo ezingajoliswanga (uhlaza, izilwanyana zasemanzini ezingenamqolo kunye neentlanzi ezikummandla wesicelo).

Kuqikelelwa ukuba ukusetyenziswa kwehlabathi jikelele kwe-glyphosate kuya kuba yi-600,000 ~ 750,000 t ngo-2020, kwaye kulindeleke ukuba ibe yi-740,000 ~ 920,000 t ngo-2025, ebonisa ukwanda ngokukhawuleza.