PDF(Pubmed)
Abstract：
Olive (Olea europaea subsp. europaea var. europaea) is the most extensively cultivated fruit crop worldwide. It is considered a wind-pollinated and strictly outcrossing crop. Thus, elevated pollen production is crucial to guarantee optimum fruit set and yield. Despite these facts, the variability of pollen production within the cultivated olive has been scarcely studied. This study aimed to characterize this feature by analysing a representative set of worldwide olive cultivars.
We evaluated the average number of pollen grains per anther in 57 principal cultivars over three consecutive years. We applied a standard generalized linear model (GLM) approach to study the influence of cultivar, year and the previous year\'s fruit load on the amount of pollen per anther. Additionally, the K-means method was used for cluster analysis to group cultivars based on their pollen production capacity.
Pollen production per anther was highly variable among olive cultivars. The cultivar significantly accounted for 51.3 % of the variance in pollen production and the year for 0.3 %. The interaction between the two factors explained 8.4 % of the variance, indicating that not all cultivars were equally stable in producing pollen across the years. The previous year\'s fruit load and its interaction with the year were significant, but barely accounted for 1.5 % of the variance. Olive cultivars were classified into four clusters according to their capacity to produce pollen. Interestingly, the fourth cluster was composed of male-sterile cultivars, which presumably share this character by inheritance.
Pollen production per anther varied extensively within the cultivated olive. This variation was mainly driven by the cultivar and its interaction with the year. The differential capacity of olive cultivars to produce pollen should be considered not only for designing new orchards but also gardens where this species is used as an ornamental.
We evaluated the average number of pollen grains per anther in 57 principal cultivars over three consecutive years. We applied a standard generalized linear model (GLM) approach to study the influence of cultivar, year and the previous year\'s fruit load on the amount of pollen per anther. Additionally, the K-means method was used for cluster analysis to group cultivars based on their pollen production capacity.
Pollen production per anther was highly variable among olive cultivars. The cultivar significantly accounted for 51.3 % of the variance in pollen production and the year for 0.3 %. The interaction between the two factors explained 8.4 % of the variance, indicating that not all cultivars were equally stable in producing pollen across the years. The previous year\'s fruit load and its interaction with the year were significant, but barely accounted for 1.5 % of the variance. Olive cultivars were classified into four clusters according to their capacity to produce pollen. Interestingly, the fourth cluster was composed of male-sterile cultivars, which presumably share this character by inheritance.
Pollen production per anther varied extensively within the cultivated olive. This variation was mainly driven by the cultivar and its interaction with the year. The differential capacity of olive cultivars to produce pollen should be considered not only for designing new orchards but also gardens where this species is used as an ornamental.
摘要：
目标：橄榄（橄榄亚种。europaeavar.europaea）是世界上种植最广泛的水果作物。它被认为是风授粉和严格杂交的作物。因此，提高花粉产量对于保证最佳坐果和产量至关重要。尽管有这些事实,栽培橄榄中花粉产量的变异性几乎没有研究。这项研究旨在通过分析一组具有代表性的全球橄榄品种来表征这一特征。
方法：我们评估了连续三年57个主要品种的平均花粉粒。我们应用标准的广义线性模型(GLM)方法来研究品种的影响，每年和前一年的果实负荷对每个花药花粉量的影响。此外,K-means方法用于聚类分析，根据花粉生产能力对品种进行分组。
结果：油橄榄品种的花药花粉产量差异很大。品种占花粉产量差异的51.3％，年份占0.3％。这两个因素之间的相互作用解释了8.4%的方差，表明并非所有品种多年来在产生花粉方面都同样稳定。前一年果实负荷及其与年份的交互作用显著，但几乎没有占差异的1.5%。橄榄品种根据其产生花粉的能力分为四个簇。有趣的是,第四个集群由雄性不育品种组成，大概是通过继承来分享这个角色的。
结论：栽培橄榄中每个花药的花粉产量差异很大。这种变化主要是由品种及其与年份的相互作用驱动的。不仅在设计新果园时，而且在将该物种用作观赏植物的花园中，都应考虑橄榄品种产生花粉的能力差异。
方法：我们评估了连续三年57个主要品种的平均花粉粒。我们应用标准的广义线性模型(GLM)方法来研究品种的影响，每年和前一年的果实负荷对每个花药花粉量的影响。此外,K-means方法用于聚类分析，根据花粉生产能力对品种进行分组。
结果：油橄榄品种的花药花粉产量差异很大。品种占花粉产量差异的51.3％，年份占0.3％。这两个因素之间的相互作用解释了8.4%的方差，表明并非所有品种多年来在产生花粉方面都同样稳定。前一年果实负荷及其与年份的交互作用显著，但几乎没有占差异的1.5%。橄榄品种根据其产生花粉的能力分为四个簇。有趣的是,第四个集群由雄性不育品种组成，大概是通过继承来分享这个角色的。
结论：栽培橄榄中每个花药的花粉产量差异很大。这种变化主要是由品种及其与年份的相互作用驱动的。不仅在设计新果园时，而且在将该物种用作观赏植物的花园中，都应考虑橄榄品种产生花粉的能力差异。
