Research on Al^(3+) Tolerance among Different Buckwheat Genotypes

[Objective] The research aimed to select the buckwheat accessions with higher Al3＋ tolerance.[Method]25 buckwheat accessions were used as materials,the Al3＋ tolerance were studied by means of solution culture method in this research.The length of root was used to evaluate the degree of Al3＋ tolerance.[Result]The root growth of some buckwheat accessions were significantly promoted under the concentration of 500 μmol/L,while high concentration of Al3＋（1 000 μmol/L）inhibited the buckwheat roots growth.There were great variations of Al3＋ tolerance among the different buckwheat genotypes.[Conclusion]Among the 25 buckwheat genotypes,L2081 and T442 had much higher Al3＋ tolerance than the others,which could be used for research on the buckwheat breeding and the mechanism of the buckwheat Al3＋ tolerance.

Molecular Characterization of Atlas 66-Derived Wheat Near-Isogenic Lines Contrasting in Aluminum (Al) Tolerance

Aluminum （Al） toxicity is the major limiting factor for wheat growth in acidic soils. Genetic improvement of Al tolerance is one of the most cost-effective solutions to improve wheat productivity. The objective of this study was to characterize near isogenic lines （NILs） contrasting in Al tolerance derived from Atlas 66 in the backgrounds of Al-sensitive cultivars Chisholm and Century using amplified fragment length polymorphism （AFLP） and simple sequence repeat （SSR）. A total of 200 AFLP and 88 SSR primer pairs were screened and 12 markers （11 AFLPs and one SSR） were associated with Al-tolerance in NILs of at least one recurrent parental background. Among them, nine were linked to A1 tolerance in the Chisholm-derived NILs, seven were associated with Al-tolerance in the Century-derived NILs, and three AFLPs derived from the primer combinations of pAG/mGCAG, pCAG/mAGC and pGTG/mGCG, and one SSR, Xwmc331 on chromosome 4D, associated with A1 tolerance in NILs of both recurrent parental backgrounds. Those common markers across two backgrounds may be the major marker loci associated with Al-tolerance in Atlas 66 and could be useful for marker-assisted breeding to improve Al tolerance in wheat. In addition, evaluation of Al tolerance among different genotypes using hematoxylin stain and relative root growth revealed that Atlas 66 was more tolerant to Al stress than the NILs, therefore suggested that the Al-tolerant NILs might not carry all Al-tolerance loci from Arias 66 and inheritance of Al tolerance in Arias 66 is more likely multigenic.

Progress on Molecular Mechanism of Aluminum Resistance in Rice

Aluminum(Al)toxicity in acid soils is a significant limitation to crop production worldwide,as 13%of the world's rice is produced in acid soil with high Al content.Rice is likely the most Al-resistant cereal and also the cereal,where Al resistance is the most genetically complex with external detoxification and internal tolerance.Many Al-resistance genes in rice have been cloned,including Al resistance transcription factor 1(ART1)and other transcription factors,organic acid transporter genes,and metal ion transporter gene.This review summarized the recent characterized genes affecting Al tolerance in rice and the interrelationships between Al and other plant nutrients.