Genetic Plasticity for Root Architectural Traits in Backcrossed Population Derived from Wild Rice (Oryza rufipogon Griff) under Low Soil Phosphorous condition

Author: Honnappa, Anantha M. Siddaiah, Padmashree R., C. Gireesh, Kalyani M. Barbadikar, J.R. Diwan, Manoj C. A., Basavaraj P.S., Muralidhara B., Ajita V. and Banoth Vinesh

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Abstract

Soil phosphorous (P) deficiency is one of the limiting factors in rice production and productivity contributing more than 50% of soil with P deficient, particularly in upland and rainfed lowland cultivations. Since P is diffusion limited in depleted zones developed around roots, root architecture traits are become prime importance for P acquisition including root length, root volume, root density in terms of fresh and dry weight basis which will ultimately support to the above ground portion of the plant growth. Oryza rufipogon Griff, a cultivated wild relative (CWR) of rice which is known to be a good source for low P tolerance trait. Hence the present study was undertaken to assess genetic variation along association between interrelated traits in relation to the low soil P conditions for the backcrossed populations derived from the cross between Samba mahasuri and (Oryza rufipogon Griff). The results revealed that, MSS due to genotypes were highly significant (p<0.01 and p<0.05) for all the traits under study, viz., number of tillers per plant, root length, root volume, shoot fresh and dry weight, root fresh and dry weight, root to shoot ratio on dry weight basis considering both two seasons of low P and one season of control conditions respectively, except for shoot length under low P during Rabi and root to shoot ratio on wet weight basis under control during Kharif season. Wide range of genetic variation were recorded for the traits such as root length, root fresh and dry weight, shoot fresh and dry weight and root to shoot ratio on wet weight basis with high GCV and PCV and high heritability coupled with high GAM. Inter-correlation among the component traits such as numbers of tillers per plant, root length, shoot length, root volume, shoot fresh and dry weight, root fresh and dry weight and root to shoot ratio on wet and dry weight basis exhibited strong association between them, even considering under stress and control conditions.

Keywords

Oryza rufipogon Griff, Root architecture, Low soil phosphorous, Root volume, Root length

Conclusion

The current study revealed that the root length, root volume, shoot dry weight, root dry weigh and root to shoot ratio are the best parameters for indicating the low soil P tolerance due to their high plasticity with availability of nutrients like P from the root zones. Presence of significant variation has been observed along with high GCV and PCV, high heritability coupled with high GAM reported for these traits for the test genotypes studied, indicate the potentiality of the ILs to contribute novel sources for improvement of these root traits under low soil P condition. The association studies of tiller number with root related traits reveals that, inter-correlation among the component traits such as numbers of tillers per plant, root length, shoot length, root volume, shoot fresh and dry weight, root fresh and dry weight and root to shoot ratio on wet and dry weight basis exhibited strong association between them, even considering under stress and control conditions.

References

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How to cite this article

Honnappa, Anantha M. Siddaiah, Padmashree R., C. Gireesh, Kalyani M. Barbadikar, J.R. Diwan, Manoj C. A., Basavaraj P.S., Muralidhara B., Ajita V. and Banoth Vinesh (2023). Genetic Plasticity for Root Architectural Traits in Backcrossed Population Derived from Wild Rice (Oryza rufipogon Griff) under Low Soil Phosphorous Condition. Biological Forum – An International Journal, 15(3): 370-378.