Rapid and Nondestructive Methods to Capture the FlowerOpening Time in Rice to Identify Donors forHigh Temperature Stress


      The time of day of flowering or the early morning flowering (EMF) trait has been demonstrated to significantly reduce heat stress damage by employing an escaping mechanism. Early flower opening is being one of the important traits that aids in the escape of rice flowers from spikelet sterility due to the high temperature stress. This strategy, which is less explored, can be used to breed cultivars that escape heat at flowering because of their early morning flowering (EMF) trait. With the advancement of instrumentation, the study was proposed to screen the genotypes using rapid and non-destructive methods like use of interval shot cameras to identify EMF traits. Once the early morning flowering trait is identified and studied for heat tolerance, it can be used as a potential donor in rice breeding programs to develop an early morning flowering variety for high temperature prone areas. The already available diverse rice germplasm collections having wide genetic diversity for FOT based on First Spikelet Opening Time (FSOT) at PBS, TNAU was used in this study. Nearly twenty one rice germplasms (landraces) were grown under natural ambient conditions (field) and interval shot cameras were used to capture the time of flower opening (Start, peak and end of anthesis) to identify the early morning flowering trait. These lines with EMF trait will be suitable donors to high temperature stress tolerance. Among them two lines namely, Mattikar and Panamara samba showed early morning flowering trait.
Key Words: : Rice, Early morning flowering, High temperatures stress, Donors