DANOS CAUSADOS PELA LARVA-ALFINETE EM MILHO EM CONDIÇÕES DE CAMPO - AFONSO-ROSA, ANA PAULA; MEDINA, LAUREN BITTENCOURT; HELLWIG, LETICIA; TRECHA, CALISC DE OLIVEIRA; FIPKE, MARCUS VINÍCIUS (International Journal of Maize & Sorghum, 2017)
<!--[if gte mso 9]> <![endif]--> RESUMO - O objetivo desse trabalho foi avaliar os danos causados por diferentes densidades larvais de Diabrotica speciosa em milho BG 7060 H em condições de campo. O experimento foi realizado na safra 2012/2013, na Embrapa Clima Temperado (S 31°49.268 e W 52°27.472). Cada parcela foi constituída de seis linhas de 5 m x 0,70 m. As plantas foram infestadas com 0, 5, 15, 30 e 40 larvas/planta. Foram avaliados, 64 dias após a infestação, o peso e o comprimento e dano em raízes e, na ocasião da colheita, a altura da planta e inserção da espiga e o rendimento. Não foi observada redução significativa do peso de raízes infestadas com larvas de D. speciosa. O comprimento das raízes foi numericamente maior quando não houve infestação larval, e a altura de plantas e a inserção da espiga não foram influenciadas pela infestação. De acordo com a escala de Iowa State 1-6, independentemente do número de larvas inoculadas às raízes, os danos foram abaixo de 2,0 (1,29 - 1,74). Pela escala de Iowa 0-3, verificou-se dano inferior a 0,75 (0,23 - 0,60). Em relação ao rendimento, de modo geral, à medida que aumentou a densidade larval, houve redução no rendimento. Palavras-chave: Diabrotica speciosa, injúrias, infestação artificial, raízes. DAMAGE CAUSED BY CORN ROOTWORM IN CORN FIELD CONDITIONS ABSTRACT - The aim of this study was to evaluate the damage caused by different larval densities of Diabrotica speciosa in maize BG 7060 H under field conditions. The experiment was conducted in the field in 2012/2013, at Embrapa Clima Temperado (31°S 52°W 49,268 and 27,472). Each plot consisted of six rows 5 m x 0.70 m and the cultivar used was BG 7060 H. The plants were infested with 5, 15, 30 and 40 larvae/plant, and there was a control (no larvae). The damage, weight and length of roots were evaluated 64 days after infestation (DAI) (22/01/2013). At the harvest, plant and ear height and yield were evaluated. No significant reduction in the weight of roots infested with larvae of beetles was observed. The root length was numerically higher when there was no larval infestation. Plant and ear height was not affected by the infestation. According to Iowa State 1-6 damage scale, regardless of of the number of larvae inoculated to roots, damages were below 2.0 (1.29 to 1.74). According to scale of Iowa 0-3, there was damage less to 0.75 (0.23 to 0.60). In relation to yield, it was observed that, in general, as increased larval density, there was a reduction in yield. Keywords: Diabrotica speciosa, injuries, artificial infestation, roots. <!--[if gte mso 9]> Normal 0 21 false false false PT-BR X-NONE X-NONE <![endif]--><!--[if gte mso 9]> <![endif]--><!--[if gte mso 10]> <mce:style><! /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabela normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; text-align:justify; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} --> <!--[endif] -->