Water Stress at Anthesis and Storage Temperature Affected Growth and Germinability of Rice (Oryza spp.)

Abstract

A study conducted in 2017 and 2018 investigated components of yield (CY) from upland rice plants predisposed to water stress at anthesis and germinability indices (GI) of harvested seeds stored at different storage temperatures. Sixteen treatments comprising four rice cultivars: CG-14, NERICA2, NERICA4 and FARO-66 predisposed to four periods of water stress [5, 10, 15 days interval and 100% Field capacity (control)] at grain filling were laid out in a completely randomized design (CRD) with six replicates. Morphological and yield parameters and GI were evaluated following standard procedures. Data were analyzed using linear regression and ANOVA with means separated using Duncan’s multiple range test (p≤0.05). Occurrence of water stress at grain filling had deleterious effects on CY and GI of seeds of FARO-66 cultivar. NERICA4 and CG14 tolerated moisture stress better than NERICA2 and FARO-66. Sterility, unfilled grain and GI are strongly (R2=0.87) related to prolonged drought incidence. Occurrence of drought at generative growth stage in rice could cause total crop failure and poor seed germinability. Considering the unpredictability of rainfall season in rainfed farming system, irrigation plan should be essential cultural practice that must be factored into upland rice production to avoid crop failure.

Keywords

• moisture stress
• upland rice varieties
• storage temperature
• seed germinability