Productivity and forage quality of sorghum irrigated with saline Waters

Abstract The dry matter yield and the chemical composition of two sorghum genotypes, CSF 18 and CSF 20, irrigated with waters of different salt levels, 0.90 (well water), 2.60, 4.20 and 5.80 dS m-1, were evaluated. A completely randomized block design, in a factorial arrangement (2 x 4), with four replicating was adopted. The experiment was set up in the field, during the dry season, in spacing of 0.80 x 0.10 m. At 112 days after sowing, the plant height was measured and the plants were harvested to evaluate biomass production and chemical composition. Plants containing completely open panicles were harvested and pre-dried and triturated samples were used to perform bromatologic analysis. Increase in salt levels in irrigation water reduced plant height and yield, especially in CSF 18 genotype. Salinity also reduced crude protein and protein yield in both genotypes, but reduced soluble carbohydrates only in CSF 18 genotype. On the other hand, effects of saline water on the neutral and acid detergent fiber levels were not observed.

摘要 本研究以两个高粱基因型CSF 18与CSF 20为试材，设置0.90 dS·m⁻¹（即井水）、2.60、4.20及5.80 dS·m⁻¹共4个盐水平灌溉处理，评估其干物质产量与化学成分。试验采用2×4因子组合的完全随机区组设计，设置4次重复，于旱季在大田开展，种植规格为0.80×0.10 m。于播种后112天测定株高并收获植株，以评估生物量产量与化学成分。收获完全抽穗的植株，经预干燥后磨碎制样，用于开展常规营养成分分析。结果显示，灌溉水盐水平升高会显著降低株高与产量，该抑制效应在CSF 18基因型中尤为突出。盐分胁迫同时降低了两个基因型的粗蛋白含量与蛋白产量，但仅在CSF 18基因型中降低可溶性碳水化合物含量。此外，未观测到咸水灌溉对中性洗涤纤维与酸性洗涤纤维含量产生显著影响。