Oil Palm Pollen Research Articles

Quantitative Assessment of Oil Palm Pollen After 23 Years Of Cryobanking

Cryopreservation of pollen grains is an effective means of conserving desired germplasm of crop plants. Cryoconserved pollen are expected to be long-lived and thus can be suitably retrieved to overcome hybridization constraints imposed by a variety of reasons. We ascertained the performance of oil palm pollen grains (Tenera hybrids) that were cryobanked 23 years ago using liquid nitrogen (196°C). Cryostored pollen were assessed for viability, in-vitro germinability and vigour. Our analysis showed a marginal decline in viability, assessed through fluorochromatic reaction test, of cryopreserved pollen as compared to fresh ones (pre-storage assessment); however, the viability did not decline in the cryostate since it was last tested 15 years back. On the other hand, germinability and vigour of cryopreserved pollen were maintained to the levels of fresh pollen. Our study, for the first time, demonstrates the amenability of pollen grains for cryopreservation of any plant species beyond a period of two decades in general, and that for oil palm in particular.

A Biosecurity Tool: High-Intensity, Pulsed Polychromatic Light and UV-C Treatments of Oil Palm Pollen and Spores of Fusarium oxysporum f. sp. elaeidis

The movement of oil palm ( Elaeis guineensis) pollen as a germplasm material between oil palm-growing countries for the purposes of plant-breeding programs is common in West Africa, Southeast Asia, and South America. Reports of pollen contamination with Fusarium oxysporum f. sp. elaeidis ( Foe), the causal agent of Fusarium wilt disease for oil palm, heightened the need for an operational decontamination technique for oil palm pollen prior to export. In this study, high-intensity, pulsed polychromatic light (HIPPL) and conventional UV (UV-C) were used as decontamination tools to treat Foe spores and oil palm pollen. We combined qualitative studies for HIPPL- and UV-C-treated Foe spores and quantitative studies for treated pollen. The study showed that despite UV-C and HIPPL successfully controlling Foe, oil palm pollen had reduced viability or was inviable upon exposure to various doses of UV-C and HIPPL sources. The effects of UV-C at doses of 2.5, 5, and 10 kJ/m2 and HIPPL at 10, 20, and 40 pulses were determined for oil palm pollen and Foe germination. UV-C doses of 10 kJ/m2 and 40 pulses of HIPPL showed significant reduction in germination of oil palm pollen but had no adverse effect on Foe viability. At 60 kJ/m2 of UV-C and 240 pulses of HIPPL, Foe was inviable, and pollen could not germinate. [Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .

Pollen germination genes differentially expressed in different pollens from Dura, Pisifera and Tenera oil palm ( Elaeis guineensis jacq.)

Abstract Oil palm (Elaeis guineensis jacq.) is considered as the king of world’s oil crops because it is the highest oil producing crop in the world. Pollination is perfectly important to increase fruits and yield because it is the first step in fruit development process. However, very few limited publications are available on the study of oil palm pollen. In this study, Elaeis guineensis importin subunit beta-1-like, mRNA sequence (XP_010939614.2, 3314 bp in length) which showed 76% identity to rice pollen-expressed gene (rice Importin β1), importin subunit beta-1, was downloaded to study the gene expression pattern of oil palm pollen. For gene expression analysis with real time quantitative PCR, the accuracy of the determination of target gene expression depends on the use of reliable reference gene. In order to identify suitable reference gene, we selected the most commonly used reference genes (Act, Apt, cyc and eIF) and ranked their expression stabilities using two statistical algorithms; geNorm and NormFinder. The results from both algorithms showed that Act was the most stable gene for oil palm pollen germination gene. Expression analysis of oil palm pollen gene in three different fruit forms showed that the expression levels of pollen gene in Dura and Tenera fruit forms were down-regulated after germination while up-regulation was observed in Pisifera. This research will be useful in future molecular genetics resource studies of gene expression in pollen germination of oil palm.

Differential pollen longevity in Dura and Pisifera oil palm (Elaeis guineensis) fruit types at storage temperatures

Oil palm (Elaeis guineensis Jacq.) is the richest source of vegetable oil in the world. Specific reproductive nature of the crop necessitates artificial pollination by collection and storage of pollen for breeding as well as generation of planting material for commercial cultivation. However, little information is available on the pollen viability and storage behavior of oil palm. The present study was conducted to standardize the processing and storage of oil palm pollen in respect of Dura and Pisifera fruit forms/types. Pollen of these two fruit forms were stored up to one year at room temperature (33±2°C), refrigerator(5°C), freezer (-5°C) and in deep freezer (-20°C) and the viability as well as germination were compared. For both the fruit types, pollen viability and germination declined as the storage temperature increased up to room temperature and the maximum germination was recorded in pollen stored under -20°C storage. Therefore, deep freezer can be used without any deleterious effect on pollen viability as well as germination. Pollen longevity was significantly reduced when stored at room temperature. Of the two oil palm fruittypes, Pisifera retained greater pollen viability and germination than Dura under all four storage temperatures. To the best of our knowledge, this is the first report of differential response of pollen from Dura and Pisifera fruit types in oil palm to storage temperatures.

Optimization of culture medium and temperature for the in vitro germination of oil palm pollen

Pollens from two different types of oil palm, Pisifera and Dura, were used to study the influence of different medium components and temperature on oil palm pollen germination. The results of our study revealed that Murashige and Skoog (MS) and sucrose (0.05% MS+0.01g/mL sucrose) played a catalytic role in oil palm pollen germination and pollen tube growth. The catalytic effect could be reversed when the contents of the medium were used at higher concentrations. Besides the nutrients, temperature has also played a vital role in vitro germination of oil palm pollen. The recorded optimum temperature and time for the germination was at 31°C for 3h. A fluctuation in time and temperature has inhibited the germination rate, as well as the growth of the pollen tube to a certain level. Thus, we have concluded from this study that a proper combination of culture medium and temperature could enhance the in vitro germination of oil palm pollen. These results will be helpful in preparing pollens for oil palm pollination.

Efficacy of organic solvents for medium term storage of oil palm (<italic>Elaeis guineensis</italic> Jacq.) pollen

The oil palm is the richest source of vegetable oil in the world. The hybrid nature of crop necessitates artificial hybridization between proven parent palms which in turn require the pollen from male parent to be collected and stored without loss of viability for sufficiently long period. Reports suggested that pollen grains of various taxa could be successfully preserved in different organic solvents. In the present study, attempt was made to evaluate the suitability of organic solvents to store the oil palm pollen at 0 to -5°C temperature. Among the five solvents used, there was significant variation for viability and germination percentages. Viability was the maximum for pollen stored in Diethyl ether (90.45 %) as well as in n-Hexane (88.41%) after 200 days of storage. Viability of pollen stored in Chloroform and Acetone were moderate and in case of Methyl alcohol, complete loss of viability was observed. With respect to pollen germination <italic>in vitro</italic>, similar trend was observed. The trend was same at different intervals/period of storage. This was confirmed through <italic>in vivo</italic> pollination and fruits set studies. Thus, present method indicated that it is feasible to store oil palm pollen in non polar solvents beyond 200 days without considerable loss of viability or germination.

Fern spore and pollen airspora profile of Singapore

Monitoring atmospheric fern spore and pollen loads in Singapore was initiated in June 1990. Aside from the more numerous fungal spores, fern spores and pollen grains made up 6.2–8.6% and 4.4–5.4% of the total airspora sampled, respectively. The most frequently encountered fern spores, in descending order, were those of Nephrolepisauriculata, Dicranopterislinearis, Stenochlaenapalustris, Aspleniumnidus, Pteridiumaquilinum, and Dicranopteriscurranii. For pollen grains, the most frequently encountered, in descending order, were Elaeisguineensis, Casuarinaequisetifolia, Acaciaauriculiformis, Kyllingiapolyphylla, Podocarpus, and Poaceae pollen grains. Seasonal patterns for individual fern spore or pollen types were discernible despite the relatively uniform tropical climate in Singapore. The fern spore and pollen calendar for the period 1991–1995 was compared to that of 2005–2006 as a follow-up study to keep abreast with the rapidly changing landscape of Singapore. Diurnal patterns showing a late morning to afternoon peak period were seen in fern spores, while the peak period was in the morning for pollen types studied with the exception to oil palm pollen. Additionally, association between fern spore and pollen counts and local meteorological conditions were also analyzed and found to be highly correlated. This study has thus identified the fern spores and pollen airspora components, and determined the calendars, as well as diurnal profiles of the Singapore airspora and provides invaluable information for allergy studies by highlighting the trigger sources present in the environment.

Oil palm, arboriculture, and changing subsistence practices during Kintampo times (3600–3200 BP, Ghana)

Oil palm is an integral part of modern subsistence economies in West Africa, and archaeological evidence suggests that it also played an important role in antiquity. Steep increases in oil palm pollen during the mid- to late Holocene have been observed in the paleoenvironmental record, which some have argued may represent cultivation activities. Charred plant macroremains from archaeological sites provide an alternate means by which to examine the relationship between people and oil palm. The Late Stone Age Kintampo Tradition is associated with early domesticates alongside continued use of wild resources, leading scholars to suggest that they occupy the middle ground between foraging and farming. This paper evaluates the relationship between Kintampo and oil palm using archaeological plant remains from two sites (K6 and the B-sites) in central Ghana. Oil palm use at both sites over time indicates similar patterns of landscape utilization that may represent arboriculture. These activities can be viewed as the performance of domesticatory relationships on the landscape, which may be a more fruitful lens through which to characterize Kintampo subsistence practices.

Comparative studies on <i>In Vitro</i> storage techniques of oil palm pollen

Comparative studies on <i>In Vitro</i> storage techniques of oil palm pollen

Oil palm and prehistoric subsistence in tropical West Africa

This study reports on the analysis of macrobotanical remains recovered at three of the B-sites rock shelters in central Ghana (B4C, B5C, B6B), which were excavated under the auspices of the Kintampo Archaeological Research Project (KARP). These rock shelters yielded large quantities of Kintampo material culture as well as pottery attributed to the Punpun. The overall aims are to further our understanding of prehistoric subsistence in tropical West Africa and to address some outstanding issues relating to the economic role of oil palm through the study of macrobotanical remains. Although palynological evidence indicates a substantial rise in oil palm pollen during the Late Holocene, various interpretations of this increase have been proposed. To date, sampling and analysis of macrobotanical remains have not been designed to investigate the nature of oil palm utilisation during this period. We argue that simple archaeobotanical quantification methods indicate that oil palm use during Kintampo occupations of sites B4C, B5C, and B6B and possibly other locales was significant. As such, humans should not be ruled out as agents having an impact on Late Holocene landscapes of West Africa. These and other archaeobotanical data from tropical Africa suggest that arboriculture was a component of prehistoric subsistence.

Structural features of N-glycans linked to glycoproteins from oil palm pollen, an allergenic pollen*.

The pollen of oil palm (Elaeis guineensis Jacq.) is a strong allergen and causes severe pollinosis in Malaysia and Singapore. In the previous study (Biosci. Biotechnol. Biochem., 64, 820-827 (2002)), from the oil palm pollens, we purified an antigenic glycoprotein (Ela g Bd 31 K), which is recognized by IgE from palm pollinosis patients. In this report, we describe the structural analysis of sugar chains linked to palm pollen glycoproteins to confirm the ubiquitous occurrence of antigenic N-glycans in the allergenic pollen. N-Glycans liberated from the pollen glycoprotein mixture by hydrazinolysis were labeled with 2-aminopyridine followed by purification with a combination of size-fractionation HPLC and reversed-phase HPLC. The structures of the PA-sugar chains were analyzed by a combination of two-dimensional sugar chain mapping, electrospray ionization mass spectrometry (ESI-MS), and tandem MS analysis, as well as exoglycosidase digestions. The antigenic N-glycan bearing alpha1-3 fucose and/or beta1-2 xylose residues accounts for 36.9% of total N-glycans: GlcNAc2Man3Xyl1Fuc1GlcNAc2 (24.6%), GlcNAc2Man3Xyl1GlcNAc2 (4.4%), Man3Xyl1Fuc1-GlcNAc2 (1.1%), GlcNAc1Man3Xyl1Fuc1GlcNAc2 (5.6%), and GlcNAc1Man3Xyl1GlcNAc2 (1.2%). The remaining 63.1% of the total N-glycans belong to the high-mannose type structure: Man9GlcNAc2 (5.8%), Man8GlcNAc2 (32.1%), Man7GlcNAc2 (19.9%), Man6GlcNAc2 (5.3%).

Purification and characterization of 31-kDa palm pollen glycoprotein (Ela g Bd 31 K), which is recognized by IgE from palm pollinosis patients.

A basic glycoprotein, which was recognized by IgE from oil palm pollinosis patients, has been purified from oil palm pollen (Elaeis guineensis Jacq.), which is a strong allergen and causes severe pollinosis in Malaysia and Singapore. Soluble proteins were extracted from defatted palm pollen with both Tris-HCl buffer (pH 7.8) and Na-acetate buffer (pH 4.0). The allergenic glycoprotein was purified from the total extract to homogeneity with 0.4% yield by a combination of DEAE- and CM-cellulose, SP-HPLC, and gel filtration. The purified oil palm pollen glycoprotein with molecular mass of 31 kDa was recognized by the beta1-2 xylose specific antibody, suggesting this basic glycoprotein bears plant complex type N-glycan(s). The palm pollen basic glycoprotein, designated Ela g Bd 31 K, was recognized by IgE of palm pollinosis patients, suggesting Ela g Bd 31 K should be one of the palm pollen allergens. The preliminary structural analysis of N-glycans linked to glycoproteins of palm pollens showed that the antigenic N-glycans having alpha1-3 fucose and alpha1-2 xylose residues (GlcNAc(2 to approximately 0)Man3Xyl1Fuc(1 to approximately 0)GlcNAc2) actually occur on the palm pollen glycoproteins, in addition to the high-mannose type structures (Man(9 to approximately 5)GlcNAc2).

Evaluation of the allergenicity of tropical pollen and airborne spores in Singapore.

Sensitization to pollen and spores of the Southeast Asian tropical region is not well documented. This study evaluated the allergenicity of the tropical airspora in Singapore. On the basis of the results of an aerobiologic survey of the airspora profile of Singapore, crude extracts of 23 main spore (fungal and fern) and pollen types were prepared. A total of 231 patients with asthma and/or allergic rhinitis and 76 healthy controls were evaluated by skin prick test (SPT). Total and specific IgE levels were also quantified by the fluorescence allergosorbent test (FAST). All 23 allergenic extracts tested elicited positive SPT responses. Among the patients with atopic diseases, extracts of oil-palm pollen (Elaeis guineensis) were observed to have the highest frequency of positive reactions (40%), followed by extracts of resam-fern spores (Dicranopteris linearis) (34%) and sea-teak pollen (Podocarpus polystachyus) (33.8%). Fungal spores with the highest SPT responses were Curvularia spp. (26-32%) and Drechslera-like spores (31%). Positive responses to these extracts correlated with total serum IgE levels of the subjects and were significantly associated with the presence of atopic disease. We have documented sensitization to tropical pollen and spores in our population. Its association with atopy suggests that it has a role in allergic diseases in the tropics.

The significance of the oil palm (Elaeis guineensis Jacq.) in the late Holocene environments of west and west central Africa: A further consideration

Abundant archaeological evidence of the occurrence of the endocarp of the oil palm,Elaeis guineensis, in the rain forest and woodland savanna zones of west and central Africa from about 5000 B.P. has shown the tree to be an important element in the subsistence economy of the region; its pollen also has been recorded in most of the regional terrestrial sediments studied so far. The distinct and consistently sudden and more marked increases in this pollen during the late Holocene when compared with the late Tertiary and late Pleistocene frequencies strongly indicate that the late Holocene upsurges were due to both natural and human factors favourable for the expansion of this heliophytic tree. Reasons are given for suggesting that upsurges in oil palm pollen during the late Holocene period in this region can be used as indices of plant cultivation. While the oil palm is known from early Tertiary deposits in west Africa, its earliest palynological record from terrestrial sediments in the west central part dates back only to the early Holocene. More palynological studies of Tertiary and Quaternary terrestrial cores are required to establish with more certainty the antiquity ofE. guineensis in west central Africa.

The variability in settling velocities of some pollen and spores

Abstract The settling velocity in still air of natural and dyed spores and pollen of several species was measured using the method of McCubbin and was found to be as follows (in cm s-1): black spruce (Picea mariana), 3.19; jack pine (Pinus banksiana), 2.53; Lycopodium, 2.31; dyed Lycopodium, 2.15; oil palm (Elaeis guineensis), 3.00; dyed oil palm, 2.16 and corn(Zea Mays), 30.95. The percentage of clustered spores and pollen was taken into account but was not found to significantly affect settling velocity except in the case of dyed oil palm. Comparisons of the measured settling velocities of clustred grains were made with the model of Ferrandino and Aylor. This was found to be accurate in general, but tended to over-estimate the settling velocity of clumped spores of Lycopodium and of dyed pollen of oil palm.

Contamination of oil palm pollen and seeds by Fusarium spp.

Five Fusarium spp. were isolated from oil palm seed and pollen. F. solani and F. oxysporum were the most frequent and the 4 isolates of F. oxysporum tested were pathogenic to seedlings. The implications of pollen and seed contamination are discussed.

I. Development of suspension media

Abstract A number of aqueous solutions were evaluated as possible pollen carriers for the spray pollination of fruit trees. The viability of apple, kiwifruit, oil palm, and plum pollen was markedly reduced after pollen was suspended in water. This loss of viability could be partly overcome by slow hydration of the pollen in moist air before its suspension. The viability of hydrated oil palm and kiwifruit pollen after suspension in calcium nitrate solution of low concentration with or without boric acid, was similar to that of hydrated pollen germinated directly. Similar results were obtained with apple and plum pollens, provided that pentaerythritol was added to the suspension medium. However, the viability of apple, kiwifruit, and plum pollen that had been suspended in these media was substantially reduced during drying on a simulated stigma surface. For kiwifruit, the loss of pollen viability after drying could be partially overcome by the further addition of sodium carboxymethyl cellulose, with or without sodium alginate, to the suspension medium.

Lipid and sterol composition of the pollen of the west african oilpalm, Elaeis guineensis

The lipid classes, fatty acid methyl esters and the sterols of oilpalm pollen were analysed. The neutral lipid fraction consisted of triglycerides, esterified and free sterols and trace amounts of hydrocarbons. Monogalactosyl and digalactosyl diglycerides, phosphatidyl choline, phosphatidyl inositol and phosphatidyl ethanolamine represented the polar lipids. The major fatty acids were linoleic, palmitic and linolenic acids together with small to trace amounts of oleic, stearic, arachidic, myristic, lauric, palmitoleic and margaric acids. Unsaturated fatty acids predominated over saturated ones in the ratio of 3:2. The 4-desmethyl sterols were the major phytosterols in the free form but they constituted a lower proportion of the sterols in the esterified state. 28-Isofucosterol was isolated and characterized as the principal sterol.

Effects of Vacuum-Drying on the Viability of Oil Palm Pollen

SUMMARYPollen of the oil palm (Elaeis guineensis) was vacuum dried for various lengths of time and stored under vacuum in ampoules at 28°, 5° and −10°C. Little loss in viability over a period of 12 months was observed in any of the storage treatments when vacuum drying did not exceed one hour. Progenies resulting from crosses with pollen stored three months under vacuum have shown no anamolous seedling development.

Observations on Natural Pollination in Commercial Plantings of Oil Palm (Elaeis Guineensis) in Malaya

SummaryMost oil palm pollen is produced by male inflorescences 2–3 days after anthesis, and this pollen is the most viable. When protected, pollen viability on female inflorescences is good up to 6 days, after which it declines. The majority of the pollen remains below the canopy, especially at bunch level. Results of quantitative evaluation of pollen dispersal showed that atmospheric pollen density is very variable and is governed by numerous factors. There is a marked diurnal variation, with highest pollen density during the afternoon and a negligible amount during the night and early morning. Rain causes an immediate drop in concentration, but pollen densities were influenced more by the number of days on which rain was recorded than by total rainfall. A relationship exists between pollen density, the number of male inflorescences in the vicinity, and rainfall, but the effects of relative humidity, sunshine and wind are obscure. Whilst pollen density drops rapidly within a short distance from the inflorescence, there is a significant dispersal over greater distances than previously thought.