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Pre-emergence herbicides were tested for relative phytotoxicity to Nemaguard peach seedlings (Prunus persica) in a sand culture. Typical symptoms, phytotoxicity ratings, growth and regrowth parameters were recorded. Diuron, the mixture diu ron plus terbacil (1 :1), terbutryne and nortlurazon were rated phytotoxic at concentrations as low as 1 mg r 1 with little recovery in the regrowth. Terbacil and simazine caused moderate initial phytotoxicity at concentrations up to 3 mg 1-1 but the seedlings showed recovery in the regrowth. Oryzalin at 6 mg 1-1 and higher caused stunting of growth, especially with the regrowth, while trifluralin, pendimethalin, napropamide and prodiamine proved to be relatively safe to peach seedlings at concentrations up to 6 mg r1.Vooropkoms onkruiddoders is getoets vir hul relatiewe fitotoksisiteit teenoor perskesaailinge in 'n sandkultuur. Tipiese simptome, graad van fitotoksisiteit, groei en hergroei parameters is b'epaal. Diuron, die mengsel diuron plus terbasil (1 :1), terbutrien en nortlurazon was fitotoksies teenoor die saailinge teen konsentrasies so laag as 1 mg 1-1 en het ook swak herstel van die hergroei getoon. Terbasil en simasien teen 'n konsentrasie van 3 mg 1-1 en laer het matige fitotoksisiteit veroorsaak, maar die saailinge het goeie herstel in die hergroei getoon. Orisalin teen 6 mg 1-1 en hOEk het groei en veral hergroei onderdruk, terwyl trifluralin, pendimethalin, napropamied en prodiamien teen konsentrasies tot 6 mg 1-1 relatief veilig teenoor perskesaailinge vertoon het.

The tolerance of 1-year-old almond seedlings (Prunus amygda/us) in a loamy sand, and newly planted peach seedlings (P. per sica) in washed river sand to low concentrations of metam-sodium (sodium methyldithiocarbamate) in the root zone was investigated. Phytotoxic symptoms were observed from 40 mg r 1 active ingredient (a.i.) on both crops but the almonds were more tolerant to higher metam-sodium concentrations. There was no indication of growth suppression, decrease in fresh mass or restricted regrowth of the peach seedlings within the concentration range of 5 to 20 mg 1-1 .Die bestandheid van 1-jaaroud amandelsaailinge in 'n lemerige sandgrond en nuut-geplante perskesaailinge in gewaste riviersand teen lae konsentrasies metam in die wortelsone is ondersoek. Ligte simptome van fitotoksisiteit is by beide gewasse vanaf 40 mg 1-1 aktiewe bestanddeel waargeneem, maar amandelsaailinge was meer bestand teen hoar konsentrasies. Geen onderdrukking van groei, afname in vars massa of beperkte hergroei is in die konsentrasiereeks vanaf 5 tot 20 mg 1-1 by perskesaailinge waargeneem nie.