Chlorophyll a fluorescence and leaf temperature are early indicators of oil palm diseases

Bud rot (BR) caused by Phytophthora palmivora and lethal wilt (LW) whose causal agent is unknown, are two diseases currently posing a threat to the oil palm (Elaeis guineensis. Jacq) industry. BR, first reported in 1964, has destroyed more than 85,000 ha. LW, first reported in 1994 in the Llanos Orientales in Colombia, has destroyed more than 5,000 ha. Chlorophyll a fluorescence is useful as a provider of information about the efficiency of the photosynthetic process when plants are subjected to biotic or abiotic stresses. Oil palms affected by BR and LW showed anomalies in the photosynthetic system, manifested by reductions in Fv/FM and ΦPSII. Changes in ΦPSII, variable fluorescence yield (Fv) and maximum fluorescence in light-adapted leaves (FM’) were observed from the start of BR infection. The most sensitive and early indicators of LW disease were leaf temperature and basal fluorescence (F0). Fv/F0 significantly changed in diseased palms, indicating problems with movement of electrons through the electron transport chain. Leaf temperature changed in response to both diseases, but variation was greater in LW. We concluded that damage to the photochemical system caused by the diseases affected the processes by which the plant captures and transports energy, causing a physiological imbalance in the plant reflected in the observed variations in chlorophyll a fluorescence and leaf temperature. The two parameters began to change early in the onset of BR and before visual symptoms appeared in LW, which is very important to the management of both diseases, the foundation of which is early detection

Complementing assisted pollination with artificial pollination in oil palm crops planted with interspecific hybrids O × G (

A total of 70 000 hectares have been dedicated to the cultivation of the interspecific hybrid O × G in Colombia as of 2020. There was a need to introduce what is known as “assisted pollination” for these O × G crops. In 2018, the Colombian Oil Palm Research Center (Cenipalma) released artificial pollination, which consists of applying naphthaleneacetic acid (NAA) as a complement to assisted pollination, with the goal of promoting the formation of oil in parthenocarpic fruits. Given the recent introduction of artificial pollination, a research study was proposed with the objective of analyzing the cost-benefit relationship from introducing artificial pollination, both during the cultivation and oil extraction stages. From a methodological point of view, the costs per unit were estimated based on the outcome from plantations in the Colombian Urabá region using two different treatments: the first consists of carrying out assisted pollination during anthesis (applying E. guineensis pollen when the flowers are receptive); the second consists of complementing assisted pollination with NAA application at 7 and 14 days after anthesis. The results indicate that the use of NAA increases net income by 7.7% per hectare of crop. Furthermore, the production costs of a metric ton of palm oil decreases by −9% mainly due to the increase in the oil extraction rate

Response of various oil palm materials (Elaeis guineensis and Elaeis oleifera × Elaeis guineensis interspecific hybrids) to bud rot disease in the southwestern oil palm-growing area of Colombia

Palms planted in an area with a high bud rot disease (BR) inoculum pressure were evaluated monthly for a six-year period to determine their tolerance, resistance, or susceptibility to the disease. Dura-type E. guineensis and OxG (E. oleifera × E. guineensis) interspecific hybrids Coari × La Me were evaluated. Of the two types of genetic material evaluated, the progenies of the E. guineensis palms showed the highest levels of incidence, reaching 90% affected palms in less than two years of evaluation. Although the hybrids showed susceptibility, they had a lower degree of affectation than the dura-type palms. The severity assessment of both genetic materials showed that the dura-type palms had the highest degree of affectation, reaching the highest values after over two years of evaluation. However, the hybrids, which were not homogeneous in terms of the level of severity, did not exceed, on average, severity level 2. According to the scale, severity level 2 is indicative of tolerance to the disease

Response of various oil palm materials (<i>Elaeis guineensis</i> and <i>Elaeis oleifera</i> &times; <i>Elaeis guineensis</i> interspecific hybrids) to bud rot disease in the southwestern oil palm-growing area of Colombia

Palms planted in an area with a high bud rot disease (BR) inoculum pressure were evaluated monthly for a six-year period to determine their tolerance, resistance, or susceptibility to the disease. Dura-type E. guineensis and OxG (E. oleifera × E. guineensis) interspecific hybrids Coari × La Me were evaluated. Of the two types of genetic material evaluated, the progenies of the E. guineensis palms showed the highest levels of incidence, reaching 90% affected palms in less than two years of evaluation. Although the hybrids showed susceptibility, they had a lower degree of affectation than the dura-type palms. The severity assessment of both genetic materials showed that the dura-type palms had the highest degree of affectation, reaching the highest values after over two years of evaluation. However, the hybrids, which were not homogeneous in terms of the level of severity, did not exceed, on average, severity level 2. According to the scale, severity level 2 is indicative of tolerance to the disease

Assessing the labor productivity of two methods of artificial pollination in oil palm crops from Colombia

Oil palm interspecific hybrids Elaeis oleífera × Elaeis guineensis (O × G) are grown across approximately 68,000 hectares in Colombia. To address the limited natural pollination capacity of O × G hybrids and the difficulties associated with assisted pollination regarding the timing of E. guineensis pollen application, the Colombian Oil Palm Research Center (Cenipalma) conducted studies on induction of parthenocarpic fruits. Cenipalma confirmed that application of 1,200 ppm of 1-naphthaleneacetic acid (NAA) at different phenological stages enabled the formation of parthenocarpic fruits. This technological advance was termed artificial pollination. This paper presents the results from a research study aimed at assessing the labor productivity for two methods of NAA application (NAA in solid mixture and NAA in liquid suspension). From a methodological standpoint, a time and motion study was conducted to assess labor productivity for each NAA application method, with time data collected using the software Cybertracker on a mobile platform (smartphone). The results indicated that a worker can cover 3.9 hectares in a working day and sprinkle 303 inflorescences in a working day when applying NAA in solid mixture. On the other hand, when applying NAA in liquid suspension, the worker can cover 3.2 hectares and sprinkle 315 inflorescences (i.e. in a working day)