Optimization in vitro conditions for plum × apricot embryo rescue and modeling some critical factors by using artificial neural networks technology

Abstract The aim of this research was to overcome abortion postzygote incompatibility, and rescuing of hybrid embryos of early and mid-ripening plum cultivars, obtained from interspecific crossing between two plum cultivars (P. salicina L.) as female parents with four apricot cultivars (P. armeniaca L.) as male parents. The effects of cultivar, embryo developmental stage, plant growth regulators (PGRs), cold treatment, embryo size and removing seed coats were investigated on embryo germination at in vitro conditions. Results showed that the best conditions for embryo rescue were: harvesting embryos at 65 d after pollination (DAP) (91.33%), using completed MS medium with 0.5 mgL−1 6-benzyladenine (BA) and 1 mgL−1 indole-3-butyric acid (IBA), and embryo Stratification for 65 and 75 DAP- embryos at 4 °C for 30 d. Larger embryos testa removing treatment showed higher germination rates. Additionally, artificial neural networks (ANNs) was used to model two outputs which are the embryo generation percentage (GP) and complete plant percentage (CFP) based on three inputs including BA, IBA and embryo developmental stage (EDS). According to Multilayer 29 Perceptron (MLP), the best germination rate (100%) and the highest percentage of complete plant (100%) can be obtained by culturing the embryos at 65 DAP on MS medium containing 0.69 mgL−1 BA and 0.95 mgL−1 IBA, or at 75 DAP on MS medium containing 0.94 mgL−1 BA and 0.98 mgL−1 IBA. The MLP results showed a high correlation between the expected  and the experimental values, which was 91.99%, 89.33% for GP and CFP, respectively. The results of the traditional statistical analysis by using Two Way ANOVA method were consistent with the results of the model obtained using MLP. Taking as a whole, this research developed an optimal protocol that may be useful in rescuing plum embryos in breeding programs.