Residual effects of soil applied atrazine on potatoes (solanum tuberosum) in selected South African soils

Abstract

The residual effect of Atrazine [2-chloro-4-(ethylamino)-6-isopropylamino)-s-triazine] has emerged as a concern because of the possibility of carryover. A study was conducted at the Florida campus of the University of South Africa (Unisa) to determine the residual effect of atrazine on follow-up bioassay vegetable crops. Potato cultivar (Moonlight) as a bioassay crop was grown separately in three soils (Sandy, Clay loam and Sandy loam soil) with four atrazine rates (0.0. 0.1, 0.2 and 0.3 mg/l) applied in each pot. The experiment was laid out as a Randomised Complete Block Design with three (3) replicates based on a fully automated greenhouse. Sandy loam soil increased plant height, number of leaves, dry weight and tuber number all at an application rate of 0.3 mg/l in comparison with Sandy and Clay loam soils. Sandy soil reduced fresh tuber weight at an application rate of 0.2 mg/l. An increase in the growth of potato parameters was caused by an increase in the application rate. The residual effect of atrazine was found to delay emergence of potatoes on Clay loam soil. Sandy loam soil proved to have performed better than Sandy and Clay loam soil for the growth of potatoes. The findings implied that the herbicides showed a reduction in efficacy as regards the emergence and growth of potato plants.

Seabe sa mašaledi a Atrazine [2-chloro-4-(ethylamino)-6-isopropylamino)-s-triazine] se tšweletše bjalo ka tlhobaboroko ka lebaka la kgonagalo ya kgogolego. Dinyakišišo di dirilwe ka khamphaseng ya Florida ya Yunibesithi ya Afrika Borwa (Unisa) go nyaka go tseba seabe sa mašaledi a atrazine go dibjalo tša merogo tšeo go nyakišišitšwego gore di amilwe ke seabe sa dibolayadibokwana. Mohuta wa sebjalo sa matsapane (Moonlight) bjalo ka sebjalo seo se angwago ke dibolayadibokwana se bjetšwe se arogane ka mebung ye meraro, mobu wa seloko, Letsopa le wa Santa (wa go hlakana le letsopa) wo o nago le dikelo tše nne tša atrazine (0.0. 0.1, 0.2 le 0.3 mg/l) o ile wa tsenywa ka pitšeng ye nngwe le ye nngwe. Tekolo ye e ile ya beakanywa ka go šomiša Tlhamo ya Sewelo ye e Feleletšego ya Poloko gomme ya ba le dikekišo tše tharo (3) go dirišwa ntlo ya bomedišetšo yeo e sepetšwago ka maitirišo. Mobu wa santa le wa seloko wo o hlakanego le letsopa o ile wa oketša botelele bja dimela, palo ya matlakala, boima bja go oma le palo ya go ntšha digwere ka moka ga yona ka ge go dirišitšwe kelo ya 0.3 mg/l ge go bapetšwa le mebu ya Santa le wa seloko wa go hlakana le letsopa. Mobu wa santa o fokoditše o boima bja digwere tše foreše ge go dirišwa kelo ya 0.2 mg/l. Koketšego ka go kgolo ya bogolo bja matsapane e bakilwe ke go oketšega ga kelo ya go e diriša. Seabe sa atrazine go hweditše gore se ditela go ba gona ga matsapane ka go mobu wa santa wa go hlakana le seloko le letsopa. Mobu wa santa wa go hlakana le seloko le letsopa o laeditše gore o šoma bokaone go phala mobu wa Santa le wa Seloko wo o hlakanego le letsopa go godiša matsapane. Dikutollo di laeditše gore dibolayadibokwana di baka go fokotšega ga go šoma gabotse ga go ba gona le kgolo ya dimela tša matsapane.

Umphumela wensalela ye-Atrazine [2-chloro-4-(ethylamino)-6-isopropylamino)-striazine] uvele njengento ekhathazayo ngoba kungenzeka ukuthi uyinto esukela kwenye. Ucwaningo lwenziwa ekhempasini yeNyuvesi yaseNingizimu Afrika (i-Unisa) eseFlorida ukuze kutholakale umphumela wensalela ye-atrazine ezitshalweni zemifino ezishubile. Izambane elibomvana elimhlophe ngaphakathi (i-Moonlight) njengesitshalo esishubile latshalwa lahlukaniswa enhlabathini eyayihlukene kathathu (Umhlabathi, Inhlabathi egcwele ubumba kanye neNhlabathi enobumba oluncane) enezilinganiso zeatrazine ezine (0.0. 0.1, 0.2 kanye no-0.3 mg/l) eyayifakwe ebhodweni ngalinye. Kwahlolwa kusetshenziswa uHlelo Lokucwaninga Kwezolimo Olubeka Izinto Ezifanayo Ngokwamaqoqo Ahlukahlukene kusetshenziswa izicucu ezintathu (3) ezifanayo ezazibekwe endlwaneni eyakhelwe ukuvikela izithombo kungqoqwane. Inhlabathi enobumba oluncane yakhulisa ubude bezitshalo, inani lamaqabunga, isisindo sokomile kanye nesibalo sezithombo ezimila ngaphansi komhlaba uma kufakwa isilinganiso esingu-0.3 mg/l uma kuqhathaniswa nomhlabathi kanye nenhlabathi egcwele ubumba Umhlabathi onobumba oluncane wanciphisa isisindo sezithombo ezimila ngaphansi komhlaba uma kufakwa isilinganiso esingama-0.2 mg/l. Ukwanda kokukhula kwemingcele yamazambane kwadalwa ukwanda kwezinga lokufakwa kwe-atrizine. Kwatholakala ukuthi umphumela wensalela ye-atrazine ubambezela ukuvela kwamazambane enhlabathini egcwele ubumba. Inhlabathi enobumba oluncane yabonakala yenza kangcono kunomhlabathi kanye nenhlabathi egcwele ubumba ekukhuleni kwamazambane. Okwatholakela kwaveza ukuthi imithi yokubulala izimila ayinamandla maqondana nokuvela nokukhula kwezitshalo zamazambane.