Location: Hard Winter Wheat Genetics ResearchTitle: Effect of cytoplasmic diversity on post anthesis heat tolerance in wheat Author
|Talukder, Shyamal - Kansas State University|
|Prasad, Vara - Kansas State University|
|Todd, Tim - Kansas State University|
|Bowden, Robert - Bob|
|Fritz, Allan - Kansas State University|
Submitted to: Euphytica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/30/2014
Publication Date: 2/3/2015
Citation: Talukder, S.K., Prasad, V., Todd, T., Poland, J.A., Bowden, R.L., Fritz, A.K. 2015. Effect of cytoplasmic diversity on post anthesis heat tolerance in wheat. Euphytica. 204:383-394. DOI:10.1007/s10681-014-1350-7.
Interpretive Summary: Most traits are inherited through the nuclear genome. However, additional genetic information is passed through maternal inheritance in plants through the cytoplasmic genome. In this study we investigated the effect of maternally inherited cytoplasms on heat tolerance. Using genetic lines that had nearly identical nuclear genomes, we evaluated the effect of cytoplasm on heat tolerance through a heat stress treatment in the growth chamber. The effects of heat stress were evaluated by measuring chlorophyll content in the plant leaves. It was found that many of the cytoplasms from wild wheat relatives had a significant effect on increasing heat tolerance in wheat. The cytoplasms investigated here may be useful for increasing heat tolerance in wheat breeding programs. The mechanism of resistance, however, is not understood and should be investigated further.
Technical Abstract: The nuclear genomes of ten alloplasmic lines were substituted by backcrossing four or five times using ‘Karl 92’, ‘Ventnor’, ‘U1275’ and ‘Jagger’ as recurrent parents to study the cytoplasmic effects on heat tolerance. During the final backcross, reciprocal crosses were made to develop NILs (Near Isogenic Lines) for cytoplasm. Sixty-eight lines of BC5 F1/ BC4 F1 and their parents were evaluated in growth chambers for post-anthesis heat tolerance. Plants were grown in the greenhouse and subjected to heat stress at 10 days after anthesis for a period of 14 days. Growth chambers were maintained at 35/30°C for heat stress and the greenhouse was maintained at 20/15°C as the optimum temperature treatment. Effects of high temperature on chlorophyll content and Fv/Fm (a chlorophyll fluorescence measuring parameter) were found to be significant in this experiment. Seven of the cytoplasms provided improved tolerance to heat with at least one recurrent parent. These results indicated that cytoplasmic variation can contribute to increase chlorophyll content and quantum efficiency of photosystem II of wheat during heat stress and also highlight the importance of interaction between cytoplasmic and nuclear genes. The role of cytoplasm may be considered in wheat breeding programs as they breed for heat tolerance, but the nature of interaction between cytoplasm and nuclear gene content needs to be better understood.