The MLO (powdery mildew locus O) gene family is important in resistance to powdery mildew (PM). In this study, all of the members of the MLO family were identified and analyzed in the strawberry (Fragaria vesca) genome. The strawberry contains at least 20 members of the MLO family, and the protein sequence contained between 171 and 1485 amino acids, with 0-34 introns. Chromosomal localization showed that the MLOs were unevenly distributed on each of the chromosomes, except for chromosome 4.
The role of polygalacturonase (PG) in the development, ripening, and softening of fruit from two strawberry cultivars with different flesh firmness and softening characteristics was compared. Changes in PG activity and gene expression during development, ripening and softening were measured. The PG genes from each cultivar were cloned and analyzed, and were classified with other PG genes using phylogenetic analysis. In Toyonoka fruit, PG activity increased gradually, reaching a peak during the pink stage, and remained at this level during post-harvest softening.
In contrast to climacteric fruits, in which ethylene is known to be pivotal, the regulation of ripening in non-climacteric fruits is not well understood. The strawberry is a typical example of a non-climacteric fruit, which has been used as a model system of these types of fruit.
Single nucleotide polymorphisms (SNPs) occur at high frequencies in both plant and animal genomes and can provide broad genome coverage and reliable estimates of genetic relationships. The availability of expressed sequence tag (EST) data has made it feasible to discover SNPs. DNA analysis is crucial in genetic studies not only for strawberry breeding programs but also for characterization of hybrids and species. We cloned 96 EST sequences, and 116 SNPs were discovered by comparing 16 strawberry cultivars grown in the region of Nanjing, China.
We investigated the success of two stingless bee species in pollinating strawberries in greenhouses. Three greenhouses and one open field area were used; one greenhouse had only strawberry plants (control), another (G1) had three colonies of Scaptotrigona aff. depilis and another (G2) had three colonies of Nannotrigona testaceicornis. In the open field area, the flowers could be visited by any bee. The total production of fruits was counted and a random sample (N = 100) from each area was used to measure weight, length, circumference, and achenes number (N = 5).