Bud rot (BR), caused by Phytophthora palmivora, is one of the most devastating diseases affecting oil palm. It has destroyed oil palm plantations in countries throughout Latin America. To assess their resistance to BR, two cultivars of African oil palm (Elaeis guineensis Jacq.) and two interspecific OxG (E. oleifera × E. guineensis Coari × La Mé and Coari × Pobè) hybrids were planted under field conditions in a plantation with a strong presence of BR. Incidence and severity data were recorded for 1812 days from the date of planting; the disease index was estimated, and progress curves were constructed and adjusted to monomolecular, logistic and Gompertz models. Severity progression and incidence progression rates for each cultivar were estimated using a simple linear regression. Statistical comparisons of the parameters were performed using Student's t-tests. Survival analyses were performed for each of the cultivars. Log-rank statistics were used to compare the responses of the cultivars to BR. Severity progression in the interspecific hybrids was significantly slower than that in the E. guineensis cultivars. No statistically significant differences were found in the progression rates among the hybrids; however, the survival analysis did show statistically significant differences. The Coari × Pobè hybrid had the longest survival time. Considering that partial resistance does not prevent plants from becoming infected but does slow disease progression, the two evaluated hybrids may have commercially valuable levels of resistance.

The oil palm replanting process produces a large amount of organic matter that, as it begins to decompose, becomes a breeding ground for various pests, including Strategus aloeus and Rhynchophorus palmarum. Different crop replanting systems are being used today. The method used depends on the plantation and it is basically associated with the costs involved in the process. However, sometimes too little attention is paid to other issues related to the new crop, such as plant health and agronomic management. This study evaluated the effect of different crop replanting alternatives in relation to two pest populations affecting oil palm plantations. Pest populations of S. aloeus and R. palmarum were assessed and monitored for 27 months using seven replanting methods. It was found that the largest number of individuals of R. palmarum and S. aloeus was associated with the stem felling and stacking method. No individuals of the two pest species were found when the felling and burying method was used. The exposed organic matter method that had the lowest number of individuals of both pest species was the felling, chipping, spreading method.