河北省滨海盐渍土地区油葵综合性状分析

Comprehensive analysis of oil sunflower traits in salinized coastal soils in Hebei Province

盐渍逆境胁迫是影响盐渍土地区油葵产量和品质的主要自然环境因素,培育耐盐优质油葵品种是盐渍土油葵育种的主要任务之一。本文采用防雨棚盐碱原土鉴定法,研究土壤含盐量为6 g·kg^(-1)下9份油葵品种苗期株高、叶面积、生物量、出苗率和出苗指数的影响,并通过隶属函数法进行苗期耐盐性初步鉴定,了解不同品种苗期耐盐性能力差异;之后在滨海盐渍化土壤大田条件下观测生育期、植株形态、产量、籽粒品质等10个农艺性状,并进行相关性分析、主成分分析和聚类分析,为滨海盐渍土地区油葵耐盐种质资源的挖掘和遗传育种提供参考。结果表明,在6 g·kg^(-1)盐碱原土处理下,不同油葵品种的各测定指标与对照(1 g·kg^(-1)左右的中壤耕层土)相比均呈现下降趋势,但不同品种的变化率有显著差异,说明油葵品种对盐分的耐受能力差异较大。通过模糊数学隶属函数法对不同油葵品种进行耐盐性排序,‘T562’、‘滨葵1号’的耐盐性最好,‘先瑞1号’的耐盐能力最弱。在田间盐渍土地区,油葵农艺性状表现各异,各性状至少与2个其他性状呈显著或极显著相关。生育期与产量构成因子呈极显著负相关,表明油葵在盐渍土环境下生长时间越长受害就越严重,越不利于油葵产量提高。根据各农艺性状的表现将滨海盐渍土种植的油葵品种进行系统聚类分析,按成熟期、产量、品质综合分为高油中产晚熟品种、早熟中产低油品种和高产中熟中等含油量品种3个类群。主成分分析将不同品种农艺性状分成3个主成分,可将其归纳为生育期和形态因子、产量因子和籽粒品质因子,其总变异累积贡献率达69%。对不同油葵品种的综合表现进行加权求和,‘滨葵1号’排名第1。结合苗期耐盐性鉴定结果综合分析认为,‘滨葵1号’和‘T562’可以作为优质品种在滨海盐渍土地区栽培及油葵耐盐育种中加以利用。

Because of soil salinization,economic benefits of agricultural lands are low in saline coastal soils.It is therefore important to improve agricultural productivity of saline coastal soils.Though oil sunflower(Helianthus annuus L.)has long been considered as economic oil crop with considerable tolerance to saline-alkaline soils,salinization-driven abiotic stress is a major natural environmental factor that adversely affects oil sunflower production and quality in saline coastal soils.To select salt tolerant oil sunflower variety with optimal traits,and provide reference for salt-tolerant germplasm resources and genetic breeding of oil sunflower,we conducted a controlled chamber test for evaluation of salt tolerance at seedling stage,and a field test for comprehensive assessment of agronomic traits of oil sunflower.In the chamber test,9 oil sunflower accessions were cultivated in saline-alkali soil and loamy soil.The saline-alkali soil was coastal saline soil with 6 g·kg-1 salt content adjusted by using weighting method.The loamy soil was a tillage layer of farmland with salt content of 1 g·kg-1,used as the control.The emergence rate and index were analyzed every 3 days after sowing,and plant height,leaf area,biomass weight of oil sunflower seedlings were measured after 20 days of sowing.In the field experiment,9 oil sunflower accessions were planted in coastal saline soil with>4 g·kg-1 salt content.Growth stage,growth and fruit traits were investigated.Salt tolerance of different oil sunflower accessions was evaluated using the fuzzy membership function.Correlation analysis,principal component analysis and cluster analysis were used to explore properties of accessions and select suitable accessions for coastal saline soil cultivation.The results showed that while the investigated indexes of seedlings of 9 oil sunflower accessions decreased under 6 g·kg-1 salt content soil,change degrees of 9 oil sunflower accessions were different.The fuzzy membership function analysis of salt tolerance of 9 oil sunflower accessions showed that‘Binkui 1’and‘T562’were strongly tolerant to salt stress,‘Xianrui 1’was the most sensitive to salt stress.The field experiment results showed that one trait was correlated(or extremely correlated)with at least two other traits.Growth period was extremely negatively correlated with production factors,indicating that suffering severe saline environments longer induced lower oil sunflower yield.Cluster analysis of agronomic traits divided 9 oil sunflower accessions into 3 groups.GroupⅠincluded 5 accessions which were high in oil content with medium yield and late maturity.GroupⅡincluded 3 accessions which were early maturing with medium yield and low oil content.GroupⅢincluded 1 accession with high yield,medium maturity and medium oil content.Principal component analysis showed that the three eigenvalues of cumulative variance proportions was 69%,which were growth period,yield factors and quality factors.The comprehensive score of‘Binkui 1’was highest in 9 oil sunflower accessions.Combined with the results of salt tolerance at seedling stage,comprehensive analysis suggested that‘Binkui 1’and‘T562’were excellent varieties of oil sunflower for salt tolerance breeding and cultivation in saline coastal soils.