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The eastern Liaoning Province of China has rich morphological diversity in walnut fruit, which is beneficial for selecting promising characters for marketability purposes. However, only a few reports have addressed morphological diversity in this region. In this study, J. mandshurica nuts and kernels from six geographical provenances were assessed for morphological traits, such as nut longitudinal diameter, nut lateral diameter, nut transverse diameter, mean diameter, nut weight, kernel weight, shell thickness, nut sutural thickness, kernel percentage, and index of roundness. Morphological traits proved to be quite variable and showed differences both within and among the geographical provenances. The frequency distribution of the traits had single peaks and followed a normal distribution. Principal component analysis revealed that 81.062% of the total variance was explained by the first three components. An unweighted PGM with averaging cluster analysis divided the geographical provenances into two groups; cluster I, containing five geographical provenances, and cluster II, containing only one. The study highlighted that the traits related to nut weight were of importance for discrimination, and Fushun is the optimal geographical provenance for breeding and selection. This study could provide a basis and reference for further understanding of the genetic resources of Juglans mandshurica fruit types. [ABSTRACT FROM AUTHOR]

The diversity of microbial communities in rhizosphere soil and non-rhizosphere soil was investigated in Juglans mandshurica plantation in Liaodong Mountain, and the relationship between the diversity and physical or chemical characteristics of soil were also studied. The results showed that most of chemical characteristics such as pH, total carbon, total nitrogen, total phosphorus and available phosphorus in rhizosphere soils were higher than that in non-rhizosphere soils significantly. The main factors affecting soil bacterial and fungal community structure are soil pH and available phosphorus (bacteria) and available nitrogen (fungi), respectively. Significant difference in the number of biomaker between rhizosphere and non-rhizosphere soils was detected for fungal, but not for bacteria. On contrast, significant difference of the diversity indexes between rhizosphere and non-rhizosphere soils were detected for bacteria, but not for fungi. These differences between rhizosphere and non-rhizosphere soils, and also between bacteria and fungi might caused by roots physiological metabolism of J. mandshurica. The dominant microbial groups are Actinobacteriota, Proteobacteria and Acidobacteriota (bacteria) and Ascomycota (fungi), which accounted for about 80% of relative abundance of bacteria or fungi. These results will provide the theoretical and scientific basis for the sustainable management and improvement of soil fertility of J. mandshurica plantation. [ABSTRACT FROM AUTHOR]