Germination‐induced changes in acyl lipids and free sterols of olive pollen

Abstract

SUMMARYThe capacity of Olea europaea L. pollen grains to germinate has been studied. They germinated poorly when incubated in media with a pH higher than 5-55. However, germination was stimulated when a stream of air was passed through the incubation medium. Phosphatidylcholine, diacylglycerols, free fatty acids and triacylglycerols are the most abundant lipids in mature and germinated pollen. The level of diacylglycerol increases during germination while phosphatidylcholine, free fatty acids and triacylglycerols decrease, as compared with mature pollen. Overall, the fatty acid composition of mature pollen lipids is similar to that of germinated pollen. Compared to phospholipids and triacylglycerols, monoacyl-, diacylglycerols and free fatty acids contain more laurate and myristate fatty acids. In relation to the amount of acyl lipids, free-.sterols are minor constituents of the lipid fraction from mature and germinated pollen, /^-sitosterol being the only significant component. The percentage of stigmasterol is significantly higher in mature than in germinated pollen.

Lipid Composition and Associated Gene Expression Patterns during Pollen Germination and Pollen Tube Growth in Olive (Olea europaea L.)

“…1A ). These values were similar to those previously reported in olive pollen ( Rodríguez-Rosales and Donaire 1988 ) but differed quantitatively from the average amount of acyl lipids present in other tissues, such as leaves, seeds and mesocarp ( Donaire et al. 1975 , Bianchi and Blahov 1994 , Hernández et al.…”

“…2000 ), Aleppo pine ( Andrikopoulos et al. 1985 ) and olive ( Rodríguez-Rosales and Donaire 1988 ) among others. Different lipid classes, such as sterols ( Villette et al.…”

“…These authors also depicted the expression patterns of several lipid biosynthetic genes that were differentially regulated in developing microspores/pollen grains and tapetal cells. A pioneer comparative study reported the lipid composition of the olive pollen grain at maturity and after 24 h of germination ( Rodríguez-Rosales and Donaire 1988 ). Transcriptomic data from olive pollen are also publicly available ( Carmona et al.…”

Lipid Composition of Arabidopsis thaliana Pollen

“…In Nicotiana benthamiana pollen, isofucosterol accounts for Lipid Composition of Arabidopsis thaliana Pollen, Table 2 Triacylglycerol composition of olive pollen. The fatty acid composition was determined via GC-FID by Rodriguez-Rosales and Donaire (1988). The fatty acid species are described by their total number of carbons and the number of double bonds Fatty acid 12:0 14:0 16:0 18:0 18:1 D9 18:2 D9, 12 18:3 D9, 12, 15 % 1.9 2.9 37.8 traces 4.3 31.4 21.7…”