Effect of aluminum stress on sesame seedling growth during germination and tolerance evaluation of sesame germplasm

Abstract

Aluminum stress is one of the important factors affecting crop growth on red soil in Jiangxi Province. To understand the aluminum toxicity on sesame growth and exploring germplasm tolerance to aluminum,Al2( SO4)3·18H2O was used to simulate aluminum stress on growth of 2 sesame cultivars Ganzhi 9 and Ganzhi 12 during germination. Seedling survivor rate,shoot length,taproot length and seedling fresh weight,were investigated under 0 to 100 mg /L Al3 +solutions. All of the traits were decreased continuously with the increase of Al3 +concentrations,especially the taproot length. All sesame seedlings died in 250 to 1 000 mg /L Al3 +solutions. These 4traits decreased under 50 mg /L Al3 +dramatically,this concentration was then used to identify 96 sesame materials including 39 upgrade varieties and 57 local germplasm. According to their relative values of the 4 traits,materials were clustered into 3 groups: 21 strong tolerant,37 medium tolerant and 38 susceptive. The 21 tolerant materials,especially Ganzhi 9,Jinhuangma and Wuninghei had potentials in future utilization. Compared to upgraded varieties,local germplasm showed superior tolerances to aluminum stress. Except survivor rate,local germplasm had higher coefficient of variation and diversity index.