Variability and Heritability Estimate of 30 Rice Landraces of Lamjung and Tanahun Districts, Nepal

Abstract

The variability in the rice landraces is the source of variation and offers substantial opportunity for the development of new varieties through the selection. Exploring diversity and variability of landraces is utmost for rice improvement. The objective of the study was to assess diversity indices, magnitude of genetic variability, heritability, genetic advance for the yield, and yield contributing traits. An experiment was carried out in alpha-lattice with 30 landraces, two replications in the Agronomy farm of IAAS, Lamjung Campus, during June-November, 2018. Shannon and Simpson's indices were calculated for 18 qualitative traits. The value of the Shannon and Simpson index ranged 0.15-1.41 and 0.07- 0.75, respectively. Landraces showed significant variations (p<0.001) for all 13 qualitative traits studied. The higher value of the phenotypic coefficient of variation (PCV) compared to the corresponding genotypic coefficient of variation (GCV) for all the studied traits indicated the influence of the environment. The filled-grain per panicle exhibited a high estimate of PCV and GCV, followed by the effective tiller and filled grain percentage. High heritability, along with high genetic advance was found in 10 traits, including 1000 grain weight, grain length, and filled grain per panicle indicated the presence of additive gene action. Direct selection of characters of these traits based on phenotypic expression by a selection method will be more reliable for yield improvement. The study suggests that the existence of diversity and estimated genetic parameters among landraces of rice that can be exploited in future rice breeding programs.

Evaluation of Physicochemical and Cooking Characteristics of Rice (Oryza sativa L.) Landraces of Lamjung and Tanahun Districts, Nepal

“…In this study also, the first principal component shows that landraces like Lekali Marsi, Thakali Lahare Marsi, Indrabeli, and Baryang Masino have a high elongation ratio which means they can fetch premium price in the market. A study on rice landraces from Lamjung and Tanahun districts reported wide diversity and huge variability for agromorphological characteristics of those landraces and suggested their utilisation in future breeding programme [31]. Thus, the result from this study in combination with similar other studies related to agromorphological characteristics can be a foundation for molecular study.…”

Multivariate Analysis of Phenotypic Diversity of Rice (Oryza sativa L.) Landraces from Lamjung and Tanahun Districts, Nepal

“…While selecting a landrace as a parent in a breeding program, other numerous factors need to be considered. us, the result from this study along with the result of Pokhrel et al [5]; Sharma et al [26], and Dhakal et al [9] can set a foundation for future rice breeding programs. Further study at the gene level can be carried out to study the variation at the genetic level.…”

“…Rice landraces are the reservoir of genetic potential and several resistant genes for biotic and abiotic stress, whereas the modern varieties are devoid of such quality [8]. Landraces are more adapted to local conditions, have a higher chance of survival and reproduction, and pass on their characteristics to the next generation [9].…”

Study on genetic variability and heritability in rice landraces (Oryza sativa. L.) under sodicity

“…High PCV and GCV was expressed by the traits such as Na + /K + ratio (59.33%, 57.66%), grain yield per plant (31.11%, 30.54%), number of grains per panicle (28.59%, 28.54%), number of productive tillers per plant (23.75%, 22.99%) and 1000 grain weight (23.20%, 23.07%). Similar findings were reported by Dhakal et al, (2020) for number of productive tillers per plant, Kumar et al, (2020) for number of grains per panicle and Devi et al, (2020) for 1000 grain weight and grain yield per plant and Keerthana et al, (2019) for Na + /K + ratio.…”