Correlation and path coefficient analysis of yield and its component traits among different accessions of the tribal pulse, Abrus precatorius L

Introduction

The tribal population of the world consumes foods which were unique depending on the region where they inhabit and markedly different from rest of the population. Abrus precatorius L. was commonly known as Jequirity bean, belongs to the family fabaceae (Prenner et al., 2013) [1] . The boiled seeds of Jequirity bean were consumed for protein source by the Onges tribe of Andaman and Nicobar. It was reported that the seeds were rich in almost all the amino acids which were essential to humans except threonine and cysteine (Rajaram et al., 1992) [2] . In the African region, the leaves of Abrus precatorius subsp. africanus was used as vegetable (Tchatchouang et al., 2017) [3] . The seed contains highly toxic albuminous protein, abrin and other antinutritional factors which will cause lethality in humans on raw consumption (Dickers et al., 2003) [4] . Various techniques to detoxify the seeds were mentioned in the ancient texts of India (Roy et al., 2012; Mansi et al., 2011; Brave et al., 2013) [5][6][7] . The plant was also known for its medicinal value in Ayurvedic, Siddha and Unani system of medicine (Chakradhari et al., 2019) [8] . Its seed was traditionally used for weighing the precious stones and gold (Boddupalli et al., 2020) [9] . The plant was reported to have various therapeutic properties like antihelmintic activity, anti-malarial activity, anti-diabetic activity and nephroprotective activity (Molgaard et al., 2001; Menan et al.,2006; Globade et al., 2009; sohn et al.,2009) [10][11][12][13] . Despite the crop was native to India, no earlier work was conducted with respect to its morphological characterization.

Materials and Methods

Source of experimental material

The Indian National Genebank of National Bureau of Plant Genetic Resources (NBPGR), New Delhi conserves 152 Jequirity bean accessions. All those accessions were Indigenous collections (IC). From this, 99 accessions (95 entries + 4 checks) were chosen on the basis of availability of required seed quantity and seed viability (%). IC0306236, IC376080, IC0469931 and IC0418097 were grown as checks. The field trial experiment was conducted by raising crops at two sites i.e. Issapur farm of NBPGR (Located at south west Delhi) and NBPGR regional station, Ranchi.

Experimental Design

The plants were raised as a sole crop at Issapur farm whereas at Ranchi station it was intercropped with Bael (Aegle marmelos). In the Genebank, only limited quantities of seeds were available. To overcome such constraints, Augmented Block Design (ABD) was chosen as the experimental design. NBPGR minimal descriptors were used for characterizing those accessions and set of 14 quantitative traits were recorded in both the locations. These traits were listed in the Table 1.

Statistical analysis

The correlation study, regression and path coefficient analysis (the effect of various traits on yield) were done by using the software R studio version 3.3.2. The scale used in the correlation and regression study was based on Searle (1965) and Lenka and Mishra (1973) [14,15].

Results and Discussion 1. Correlation study

The result of correlation analysis was shown in Table 2 and Figure 1. The scale used in the analysis was based on Searle (1965) [14] . From the results, it was observed that the association between number of inflorescence per plant (NIF_P) and number of pod cluster per plant (NPC_P) was highly significant, very strong and positive relation.

Similarly, there exists highly significant, very strong positive association was found between days to flower initiation (DFI) and days to complete pod maturity (DM). Significant moderately strong positive association was found between pod length (PL) and pod width (PW) and also between number of pods per

Regression analysis

The result of regression analysis was represented in Table 3.

In the analysis, seed yield per plant (SYP) was considered as dependent variable and all the other quantitative traits were considered as independent variable. The residual effect of 0.3124 indicated that the traits accounted for 68.76% to the variability in seed yield per plant. It shows that few other traits which were not studied in this study should be included in the analysis to account fully for the variation in seed yield per plant. It was observed that the effect of variables like number of pods per cluster (NP_C), number of pod cluster per plant (NPC_P) and number of seeds per pod (NS_P) over the seed yield per plant (SYP) was highly significant and the effect was positive and high. Whereas the effect of 1000 seed weight (1000SW) on the seed yield per plant (SYP) was highly significant but low. The effect of all the remaining traits over the seed yield per plant (SYP) was non-significant.

The result of path coefficient analysis was displayed in figure 2. The scale used in this analysis was based on Lenka and Mishra (1973) [15] . The thickness of the arrow depicts the amount of effect over the seed yield per plant (SYP). It was observed that the effect of number of pods per cluster (NP_C), number of pod cluster per plant (NPC_P) and number of seeds per pod (NS_P) over the dependent variable seed yield per plant (SYP) was high. The remaining traits have low or negligible effect over the seed yield per plant (SYP). Based on path coefficient analysis, Lekshmanan and Vahab (2018) [16] reported in cluster bean that pod clusters per plant, pod length, plant height and pods per plant were the important traits that influence pod yield. Similarly, Ahmad and Belwal (2020) [17] mentioned that the traits 100 seed weight and number of pods per plant were having maximum effect on seed yield in Mungbean.

Conclusion

Positive correlation between desirable traits was favorable to a breeder because it paves way for the simultaneous improvement of both the traits. The improvement in one trait will result in the improvement of correlated trait also.

Based on the regression and path coefficient analysis, selection for traits like number of pods per cluster, pod cluster per plant and number of seeds per pod (independent variable) will help in yield improvement (dependent variable). Hence, a plant breeder can make selection of these morphological traits to increase the yield of Ratti genotypes.

Acknowledgement

AcknowledgementThe authors wish to thank the National Bureau of Plant Genetic Resources (NBPGR) -New Delhi for providing the seed materials. The authors also like to acknowledge NBPGR regional station at Ranchi and Issapur farm for their support in conducting field trials. The authors were also thankful to University Grants Commission for its financial support in the form of Senior Research Fellowship (SRF).

References

1. Prenner G. Flower development in Abrus precatorius (Leguminosae: Papilionoideae: Abreae) and a review of androecial characters in Papilionoideae. South African Journal of Botany. 2013;89:210-218.
2. Rajaram N, Janardhanan K. The chemical composition and nutritional potential of the tribal pulse, Abrus precatorius L. Plant Foods for Human Nutrition. 1992;42:285-90.
3. Tchatchouang S, Beng VP, Kuete V. Antiemetic African medicinal spices and vegetables. In: Medicinal Spices and Vegetables from Africa. 2017;1:299-313.
4. Dickers KJ, Bradberry SM, Rice P, Griffiths GD, Vale JA. Abrin poisoning. Toxicological Reviews. 2003;22:137-42.
5. Roy S, Acharya R, Mandal NC, Barman S, Ghosh R, Roy R. A comparative antibacterial evaluation of raw and processed Guñjā (Abrus precatorius Linn.) seeds. Ancient Science of Life. 2012;32(1):20-23.
6. Barve KH, Ojha N. Effective detoxification of Abrus precatorius Linn. seeds by Shodhana. Journal of Ayurveda and Integrative Medicine. 2013;4(2):82.
7. Boddupalli RS. Traditional use of legume seeds for weighing gold in India. Indian Journal of History of Science. 2020;55(2):173-82.
8. Mølgaard P, Nielsen SB, Rasmussen DE, Drummond RB, Makaza N, Andreassen J. Anthelmintic screening of Zimbabwean plants traditionally used against schistosomiasis. Journal of Ethnopharmacology. 2001;74(3):257-264.
9. Ménan H, Banzouzi JT, Hocquette A, Pélissier Y, Blache Y, Koné M, Mallié M, Assi LA, Valentin A. Antiplasmodial activity and cytotoxicity of plants used in West African traditional medicine for the treatment of malaria. Journal of Ethnopharmacology. 2006;105(12):131-136.
10. Gbolade AA. Inventory of antidiabetic plants in selected districts of Lagos State, Nigeria. Journal of Ethnopharmacology. 2009;121(1):135-139.
11. Sohn SH, Lee EY, Lee JH, et al. Screening of herbal medicines for recovery of acetaminophen-induced nephrotoxicity. Environmental Toxicology and Pharmacology. 2009;27(2):225-230.
12. Searle SR. The value of indirect selection: I. Mass selection. Biometrics. 1965;682-707.
13. Lekshmanan DK, Vahab MA. Correlation and path coefficient analysis of yield and its component characters among different accessions of cluster bean [Cyamopsis tetragonoloba (L.) Taub.]. Legume Research -An International Journal. 2018;41(1):53-56.
14. Ahmad S, Belwal V. Study of correlation and path analysis for yield and yield attributing traits in mungbean [Vigna radiata (L.) Wilczek]. International Journal of Chemical Studies. 2020;8(1):2140-2143.