Rice Science ›› 2019, Vol. 26 ›› Issue (4): 229-238.DOI: 10.1016/j.rsci.2018.08.008

• Orginal Article • Previous Articles     Next Articles

Screening for Spikelet Fertility and Validation of Heat Tolerance in a Large Rice Mutant Population

Cheabu Sulaiman1, Panichawong Nat1, Rattanametta Prisana1, Wasuri Boonthong2, Kasemsap Poonpipope3, Arikit Siwaret1,4, Vanavichit Apichart1,4, Malumpong Chanate1()   

  1. 1Department of Agronomy, Faculty of Agriculture at Kamphaeng Saen, Kasetsart University, Nakhon Pathom 73140, Thailand
    2Faculty of Science and Technology, Rajabhat Nakhon Pathom University, Nakhon Pathom 73000, Thailand
    3Department of Horticulture, Faculty of Agriculture, Kasetsart University, Bangkok 10900, Thailand
    4Rice Science Center & Rice Gene Discovery Unit Kamphaeng Sean Campus, Kasetsart University, Nakhon Pathom 73140, Thailand;
  • Received:2018-03-31 Accepted:2018-08-22 Online:2019-07-28 Published:2019-04-04

Abstract:

A total of 10 000 M4 individuals in Jao Hom Nil (JHN) mutant population was treated with high temperature (40 ºC to 45 ºC) during the day time (6 h) from the booting to the harvesting stages, and ambient temperature (33 ºC to 35 ºC) was used as the control. The results of screening and yield trials found that the mutant line M9962 had a high spikelet fertility of 78% under heat stress. In addition, the other mutant lines, including M3181 and M7988, had a spikelet fertility of approximately 70%. However, the JHN wild type, Sin Lek, RD15 and RD33 had very low spikelet fertility of 34%, 14%, 9% and 4%, respectively. The lower spikelet fertility at an elevated temperature resulted in a dramatic decrease of filled grain and contributed to a loss in 100-grain weight. M9962 is a potential genetic stock for use in a heat tolerance breeding programme. In addition, spikelet fertility at high temperature was representative of heat tolerance and can be used as a screening trait for heat tolerance during the reproductive phase on a large scale.

Key words: high temperature, rice, spikelet fertility, heat tolerance, mutant