SENSITIVITY OF SWEET POTATO GENOTYPES TO CLOMAZONE AND WEED INTERFERENCE

ABSTRACT Sweet potato is a promising crop in Brazil due to its potential for bioenergy production. However, little information on adequate chemical weed control is found for this crop. Thus, the objective of this work was to evaluate the effect of clomazone on 20 genotypes of sweet potato and the sensitivity of these materials to weed interference. A field experiment was conducted using an experimental design with four blocks arranged in split-plots. The sweet potato genotypes Brazlândia-Branca, Cariru-Vermelha, Princesa, Tomba-Carro-1 and UFVJM (01, 05, 06, 07, 08, 10, 14, 23, 26, 30, 35, 42, 43, 46, 48 and 49) were grown for 180 days under three weed managements (soils treated with clomazone, mechanically weeded and with no weed control). The plots consisted of the weed control methods and the subplots consisted of the sweet potato genotypes. Phytotoxicity, branch growth and yield were evaluated. Plants grown with no weed interference had larger branch length. The highest yields were found in clomazone-treated soils. Weed interference reduced 81 to 99.7% of the yield. The less susceptible genotypes to weed interference were UFVJM07, UFVJM10 and UFVJM35, and the most sensitive were Princesa and UFVJM01. The root yield of plants under chemical weed control was similar to or greater than those with mechanical weed control in 17 of the 20 genotypes evaluated.

摘要 甘薯在巴西是极具发展潜力的能源作物，因其具备生物能源生产的广阔前景。然而，当前针对该作物的高效化学除草技术相关研究信息仍较为匮乏。为此，本研究旨在评估广灭灵（clomazone）对20个甘薯基因型的影响，以及这些种质材料对杂草干扰的敏感性。本试验采用裂区试验设计，设置4次重复开展田间研究。供试的20个甘薯基因型包括Brazlândia-Branca、Cariru-Vermelha、Princesa、Tomba-Carro-1以及UFVJM系列（01、05、06、07、08、10、14、23、26、30、35、42、43、46、48、49），试验周期为180天，设置三种除草管理模式：广灭灵土壤处理、机械除草与无除草对照。试验主区为除草方式，副区为甘薯基因型。本试验测定指标包括药害、分枝生长状况及产量。结果显示，无杂草干扰处理的甘薯植株分枝长度更长；广灭灵土壤处理组的产量最高；杂草干扰可使甘薯产量降低81%至99.7%。对杂草干扰耐受性较好的基因型为UFVJM07、UFVJM10与UFVJM35，而敏感性最强的基因型为Princesa与UFVJM01。在供试的20个基因型中，有17个基因型的化学除草处理块根产量与机械除草处理相当，甚至更高。