Paternity analysis in a progeny test of Cryptomeria japonica revealed adverse effects of pollen contamination from outside seed orchards on morphological traits

Abstract

To evaluate the effects of pollen contamination from outside of Cryptomeria japonica seed orchard on the growth performance (height and diameter at breast height, DBH) and morphological traits (stem straightness and basal stem straightness), paternity testing using seven microsatellite markers was performed in a progeny test. In the studied progeny test, high rates of inconsistency were found between the observed and expected genotypes. The average rates of pollen contamination from outside the orchard and self-fertilization were 58.47% and 0.65%, respectively. We divided the individuals of the studied progeny test into two groups based on their genotype data, for which: (1) both parents were elite trees and (2) only the mother trees were elite trees, and then compared them with respect to the growth performance and morphological traits of progenies using data at 20 and 30 years old. Significant adverse effects of contaminating pollen were detected in relation to straightness, but not tree height and DBH. The results suggest that the genetic gains for straightness generally show higher narrow-sense heritability than growth traits, which should be increased by reduction of pollen contamination. Breeding with paternal analysis (BWPA) is an effective approach for evaluating breeding materials based on maternal and paternal information revealed by DNA markers. The use of BWPA in progeny test allows effective forward-and backward selection without laborious and time-consuming tasks. In this study, we also suggest that the significant pollen contamination and paternal deviation found in the open-pollinated progeny test are serious impediments for BWPA.

Genomic Prediction of Tree Height, Wood Stiffness, and Male Flower Quantity Traits across Two Generations in Selected Individuals of Cryptomeria japonica D. Don (Japanese Cedar)

“…Forests 2023, 14, x FOR PEER REVIEW 3 of 18 many reports of exogenous pollen contamination in seed orchards [30,31], and mating errors may also occur during artificial crosses. Moreover, forest tree breeding takes place over many years, so when dealing with material that was bred over 50 years ago, as in the case studied here, confirmation and correction of parentage information using DNA information is essential for efficient breeding [32].…”

“…Because parentage and sibling relationships are thought to create genetic similarities between clones and influence the accuracy of GP predictions [29], prior knowledge about the genetic relationships of the studied population is important [7,12]. There have been many reports of exogenous pollen contamination in seed orchards [30,31], and mating errors may also occur during artificial crosses. Moreover, forest tree breeding takes place over many years, so when dealing with material that was bred over 50 years ago, as in the case studied here, confirmation and correction of parentage information using DNA information is essential for efficient breeding [32].…”

Simple Genetic Distance-Optimized Field Deployments for Clonal Seed Orchards Based on Microsatellite Markers: As a Case of Chinese Pine Seed Orchard

“…The efficiency of this strategy has been evaluated by progeny testing, parental selection, and construction of pedigrees [ 9 – 11 ]. Later, the BWB strategy was demonstrated in a number of tree species [ 12 – 14 ] and it has been extensively used in different areas of forest tree breeding, including phylogenetic analysis [ 15 , 16 ], mating systems [ 12 , 17 – 19 ], estimation of genetic parameters and breeding value [ 13 , 20 ], and spatial variation [ 17 ]. Selecting superior individuals directly from the open-pollinated progeny of a seed orchard or from plantations established using seed orchard seeds, coupled with identifying the phylogenetic relationship of the selected materials based on molecular markers, could decrease the reliance on controlled pollination and shorten the breeding cycle by 10–15 years [ 9 ].…”

Evaluation of the growth traits of Toxicodendron vernicifluum progeny based on their genetic groups assigned using new microsatellite markers

“…Conventionally, many forest tree improvement programs have been started with selection of plus trees, which requires significant effort, cost, and time. Recently, family reconstruction based on paternal analysis using DNA markers has become a practical method for forest tree improvement, called breeding with paternal analysis in an open-pollinated progeny test or polymix breeding with parental analysis (GRATTAPAGLIA et al, 2004;LAMBETH et al, 2001;MORIGUCHI et al, 2011). EL-KASSABY and LSTIBU°REK (2009) proposed so-called breeding without breeding (BwB), which is a breeding with paternal analysis approach for backward and forward selection in an open-pollinated progeny test.…”