Evaluation and comparison of field production performance of Pennisetum longissimumvar. intermedium in saline soil region

In Qinwangchuan saline soil region of Gansu Province, the phenological phase, growing rate, leaf area and tiller number of 4 domesticated lines of Pennisetum longissimum var. intermedium were comparatively investigated in field trials and their production performance were comprehensively evaluated with grey system theory. The result showed that line 1, 2 and 3 germinated quickly, matured early and had growth period of 147 d, in contrast, line 4 germinated slowly, matured lately and had growth period of 160 d. Line 1 was the fastest growing with significantly higher (P0.05) plant heights than the other three lines in each growth period and reached the maximum (187.94 cm) at blooming stage. Line 3 grew slowly with the lowest height of 150.51 cm at ripe stage. During the early and middle of growth stage, leaf area and stem diameter of all lines gradually increased and then stabilized or declined after heading stage. Line 1, 2 and 4 performed consistently and significantly better than the line 3. Line 2 also has the strongest tiller ability. Line 1 and 2 had fast growing rate, strong tiller ability, high hay yield and early maturity after comprehensive evaluation which were suitable for widely planting in the Qinwangchuan saline soil region.