The study of the leaf anatomical structure of macadamia germplasm resources and its drought resistance was aimed to provide theoretical basis for macadamia seed breeding, introduction and cultivation. 11 leaf anatomical parameters of 20 macadamia germplasm resources were analyzed and compared using paraffin section technique. The drought resistance of different germplasm resources was comprehensively evaluated by the principal component analysis, membership function method and systematic clustering method. The results showed that macadamia leaves were typical leaves with different faces, and there were significant differences among the anatomical structure indexes of different germplasm resources (P<0.01). Principal component analysis showed that the order of the eleven indexes reflecting the drought resistance of macadamia was thickness of palisade parenchyma thickness>leaf thickness>cell tense ratio>palisade/spongy tissue>sponge ratio>upper cuticle thickness>lower epidermis thickness>upper epidermis thickness>lower cuticle thickness>midrib thickness>spongy parenchyma thickness. According to the membership function method and the weight of each index, the order of drought resistance of the 20 macadamia germplasm resources was as follows: No. 1>No. 19>No. 5>No. 10>No. 14>No. 11>No. 16>No. 7>No. 2>No. 20>No. 8>No. 13>No. 18>No. 15>No. 9>No. 3>No. 6>No. 4>No. 17>No. 12. After "Z-score" standardization, the 20 germplasm resources were classified into 3 groups at 15 genetic distances. No. 1, No. 5, No. 10, No. 11, No. 14, No. 16 and No. 19 had thicker leaves, developed palisade tissue, higher palisade/spongy tissue and cell tense ratio than other germplasms, and had higher water retention and photosynthetic capacity, so they were high drought-resistant groups. The leaves, epidermis and cuticle of No. 3, No. 4, No. 6, No. 9, No. 12, No. 15 and No. 17 were thin, and the leaves were relatively loose, showing low drought resistance, so they were low drought resistance groups. The drought resistance of other germplasms was in the middle.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |