Abstract: In order to screen out the sea-island cotton varieties suitable for saline-alkali land cultivation, 203 sea-island cotton were selected and evaluated under natural compound salt stress. The results showed that plant height, height of the first node, fruit branch numbers, number of boll drop, proportion of boll drop and salt tolerance coefficient of yield of Single boll seed cotton were decreased. Lint percent, boll numbers, first node of fruit branch, effective boll numbers, effective fruit branch numbers, yield of single boll lint yield, seed cotton yield per plant and lint yield per plant were increased slightly. The coefficient of variation showed that the seed cotton yield per plant and lint yield per plant were the highest. The correlation analysis showed that there was a significant positive correlation between fruit branch numbers and boll numbers; proportion of boll drop has significant correlations with boll number, height of the first node, first node of fruit branch, fruit branch number, effective fruit branch numbers, effective boll numbers, number of boll drop. Yield of Single boll Lint yield has significant correlations with lint percent, boll numbers, fruit branch numbers, effective boll numbers, effective fruit branch numbers, number of boll drop, proportion of boll drop, yield of Single boll seed cotton, yield of Single boll Lint yield, seed cotton yield per plant. The correlation analyses of the lint yield per plant identification value, the principal component score, the membership value and the comprehensive score D value showed that the four were significant positive correlation (P<0.01), indicating that sea-island cotton could be comprehensively evaluated and classified by the four comprehensive scores. The sea-island cotton resources are mainly salt-tolerant and medium salt-tolerant, with relatively few extreme materials. Through comparison, it is found that the loose fruit branch type is more salt-tolerant than the compact type. In addition, a variety Pima 4 with strong compound salt tolerance was selected. The salt tolerance indexes of 6 sea-island cotton were screened by stepwise regression. The results of this experiment provide a certain theoretical basis, identification indicators and methods for the screening of sea-island cotton varieties tolerant to compound salt in the boll stage.

Key words: sea-island cotton, complex salt stress, comprehensive evaluation

摘要： 为筛选适合盐碱地种植的海岛棉品种,本试验以203份海岛棉进行自然复合盐胁迫筛选及评价。结果表明,株高、始节高、果枝数、蕾铃脱落数、蕾铃脱落率及单铃籽棉产量耐盐系数呈现下降,衣分、铃数、始节数、有效铃数、有效果枝数、单铃皮棉产量、单株籽棉产量及单株皮棉产量耐盐系数略有上升。变异系数表现为单株皮棉、籽棉产量最高。相关分析表明,果枝数与铃数存在显著性正相关,蕾铃脱落率与铃数、始节高、始节数、果枝数、有效铃数、有效果枝数、蕾铃脱落数存在显著相关性,单株皮棉产量与衣分、铃数、果枝数、有效铃数、有效果枝数、蕾铃脱落数、蕾铃脱落率、单铃籽棉产量、单铃皮棉产量、单株籽棉产量存在显著相关性。相关性分析表明,皮棉产量鉴定值、主成分综合得分、隶属函数值、综合得分D值之间均呈显著正相关(P<0.01),说明可以通过这4个指标结合进行海岛棉综合评价及分类。海岛棉资源以耐盐、中耐盐为主,极端材料相对较少,通过对比发现果枝松散型较紧凑型耐盐性更强;此外,筛选到1份耐复合盐极强品种Pima 4,并通过逐步回归筛选到6个海岛棉耐盐指标。本研究为海岛棉花铃期耐复合盐品种的筛选提供了一定的理论依据、鉴定指标及方法。

关键词: 海岛棉, 复合盐胁迫, 综合评价