Research Article

Phenotypic Diversity in Yield Determining Traits of Pea (Pisum sativum L.) Genotypes under the growing Conditions of Dera Ismail Khan, Khyber Pakhtunkhwa, Pakistan

Tehseen Ali Jilani1*, Muhammad Saleem Jilani2, Javeria Sherani3, Kashif Waseem2, Muhammad Sohail Khan2, Hasnain Saleem3, Abdul Manan2, Rashid Jawad2 and Sami Ullah4

1Department of Horticulture, Faculty of Agricultural Sciences, Ghazi University, Dera Ghazi Khan, Pakistan; 2Department of Horticulture, Faculty of Agriculture, Gomal University Dera Ismail Khan, Khyber Pakhtunkhwa, Pakistan; 3Department of Computer Sciences, Sub Campus Gomal University, Tank, Pakistan; 4Department of Agronomy, Agriculture College, Bahauddin University, Bahadur Sub Campus, Layyah, Pakistan.

Received | February 12, 2020; Accepted | January 14, 2022; Published | May 07, 2022

*Correspondence | Tehseen Ali Jilani, Department of Horticulture, Faculty of Agricultural Sciences, Ghazi University, Dera Ghazi Khan, Pakistan; Email: [email protected]

Citation | Jilani, T.A., M.S. Jilan, J. Sherani, K. Waseem, M.S. Khan, H. Saleem, A. Manan, R. Jawad and S. Ullah. 2022. Phenotypic diversity in yield determining traits of Pea (Pisum sativum L.) genotypes under the growing conditions of Dera Ismail Khan, Khyber Pakhtunkhwa, Pakistan. Sarhad Journal of Agriculture, 38(2): 701-708.

DOI | https://dx.doi.org/10.17582/journal.sja/2022/38.2.701.708

Keywords | Pisum sativum L., Genotypes, Phenotypic diversity, Plant growth, Yield

Copyright: 2022 by the authors. Licensee ResearchersLinks Ltd, England, UK.

This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).

Introduction

Yield is the inter-play of genetics, growing environment, and their interactions (Quarrie et al., 2006). Indigenous varieties show high degree of genetic and phenotypic diversity. Plant biologists are faced with the challenge of how to effectively breed for high yielding and resistant genotypes. Assessing the phenotypic diversity among genotypes for yield-related traits may become effective tool for developing better yielding varieties for specific and/or multi-environments (Casadebaig et al., 2016). Vegetables are an economical wellspring of protein for both humans consuming fewer calories. Assessing the phenotypic diversity among genotypes for yield-related traits may become effective tool for developing better yielding varieties for specific and/or multi-environments (Santalla et al., 2001; Ali et al., 2007; Jatoi et al., 2011).

Pea (Pisum sativum L.) is one of the world’s most developed vegetable crops. It is one of the major agricultural produces and is a significant segment, alongside different vegetables and oats, of the eating routine of early human advancements in the Middle East and the Mediterranean Basin. Wild pea relatives include the species P. fulvum and P. sativum subsp. elatius. Developed peas for the most part have a place with P. sativum subsp. sativum. P. sativum subsp. abyssinicum is a less often developed pea, limited to Yemen and Ethiopia (Duc et al., 2015).

Field pea (Pisum sativum L.) is among the top ranked legume crops that is consumed by humans to meet their dietary needs all over the world. It is a rich source of protein (21-25 %), carbohydrates, vitamin A and C, calcium, phosphorous, amino acids, lysine and tryptophan (Bhat et al., 2013). In Pakistan, total production of pea is about 149 thousand tonnes from an area of 23.6 thousand hectares (FAOSTAT, 2016). Pod yield of pea highly depends on climatic conditions of the cultivated area and genotypic variability of variety grown for better adoptability and high yield (Khichi et al., 2017). Existence of genotypic differences among grain legumes is an indication for improvement through conventional selection procedures (Coulibaly et al., 2002). Seboka and Fikresilassie (2013) conducted experiments on sixteen field pea genotypes and reported that seed yield had positive and significant correlation with grain filling periods, plant height, number of seeds pod-1, seed plant-1 and pod length. Kosev (2015) highlighted the cumulative effect of yield contributing traits and indicated that number of grains plant-1, pod length and grain weight had the highest effect on seed yield.

Actual yield as characterized is the immensity of seed collected than the immensity of seed planted. Especially in large seeded vegetables in low yielding situations, yield in essence is certifiably not an ideal estimation of financial efficiency. Two cultivars of peas with a similar yield potential (6735 kg/ha) yet extraordinary seed sizes, were compared that showed differences in yield due to varietals differences. Actual yield is a greater amount of productivity than the basic estimation of grain yield at crop since it signifies seed cost. Yield potential is the genetically decided capacity of a harvest to produce ideal yield in a given agro-climatic environmental condition. Yield potential is believed to be in part verbalized by seed evaluation, and various investigations have attempted to comprehend the correlation between seed size and yield in pea. All these actual and potential yield differences were due to genotypic variability and different agro-climatic conditions (Biger, 2009; Gusmao et al., 2012).

Agricultural research in developing countries is mainly focused to assess various cultivars for their suitability to be grown in suitable growing conditions for guaranteeing best yield potential of that crop within available resources. Explicit zones need specific variety that could better grow under the prevailing conditions of the area. Little consideration has been given to varietals improvement of peas outside the temperate region of developed countries. Hence, keeping in view the importance of pea crop for ensuring food security with recommendation of specific variety for a specific area, present investigations were carried out to evaluate pea varieties for yield and its contributory traits under the agro-climatic conditions of Dera Ismail Khan (D. I. Khan), Khyber Pakhtunkhwa, Pakistan during two normal growing seasons.

Materials and Methods

Field experiments were conducted to assess the phenotypic diversity in diverse pea genotypes for yield determining traits under the tropical environment of D. I. Khan, Khyber Pakhtunkhwa, Pakistan (latitude 320 4’ N, longitude 710 2’, altitude of 173m) during two growing seasons (2013-14 and 2014-15). To reduce chance of error, experiments in both seasons were planted in Randomized Complete Block Design (RCBD) with three replications. Plant material included ten genotypes (Indeterminate) that are designated as Climax (Cli), Coronado (Cor), Dasan (Das), Faisalabad (Fsd), Green feast (Gre), Meteor (Met), Minarellet (Min), PS-40 (P4), Rando (Ran), and Shareen (Sha) genotypes.

Soil was sampled before starting the experiment, for various physico-chemical properties according to standard procedures (Table 1). Organic matter was determined by dicrome oxidation method Walkley and Black (1943). EC and soil pH were measured in a 1/5 soil/water extract. Soil Nitrogen was measured by method given by Hesse (1971). The available P was measured with the method given Olsen et al. (1954). K was determined by the procedure given Junsomboon and Jakmunee (2011). All plant production and protection measures were adopted accordingly. Both experiments were planted at 26th September and seeds were planted at ridges, where R×R and P×P distance was maintained 100 cm and 30 cm, respectively. These ten genotypes were commonly grown in Pakistan. The objective of determining phenotypic diversity was to evaluate most suitable genotype specially for this climatic condition. The source seed was NARC and Ayub Agriculture Research Institute, Faisalabad. Data regarding climate was collected from meteorological station located nearby the experimental site (Table 2). The plants were harvested at last week of February on both years. At physiological maturity, five plants from each treatment were selected and data were recorded on days to flowering (DF), plant height (PLH, cm), number of pods plant-1 (PN), weight of pods plant-1 (PWT, g), pod length (PL, cm), pod width (PW, cm), number of grains pod-1(GN), and pod yield (PY, t ha-1). Collected data were subjected to analysis of variance technique as outlined by Steel et al. (1997). Least Significance Difference (LSD) at 5% probability was used to assess the extent of variability among pea genotypes. All statistical analyses were performed in IBM SPSS, version 22 (IBM corp., NY, USA).

 

Table 1: Physical and chemical properties of the experiment soil.

Property	Unit	2013-14	2014-15
N	(mg kg-1)	12.98	13.03
P	(mg kg-1)	0.52	0.71
K	(mg kg-1)	327.87	332.13
Organic matter	%	0.60	0.71
pH	-	8.20	8.10
EC	dS m-1	4.38	4.47
Sand	%	14.89	14.70
Silt	%	75.10	74.50
Clay	%	10.00	10.80
Textural class	-	Silt loam	Silt loam

 

Results and Discussion

Days to flowering

Pea genotypes presented significant (P<0.05) differences for days to flowering (DF) in both the growing seasons (2013-14 and 2014-15) (Figure 1). It ranged from 55.48 to 78.77 in 2013-14 and from 54.84 to 75.13 in 2014-15. Genotype Min and Ran took minimum days to flowering (55.48, 56.55 respectively) whereas Das took maximum days to flowering (78.77) in 2013-14. Almost similar results were recorded in 2014-15, however, genotype Met also took maximum (75.13) days to flowering (Table 1). Finding enclosed that all the other genotypes intermediary responded to flowering during both the seasons. Previously conducted studies had also drawn similar conclusion of differential response of varieties to flower initiation (Khokhar et al., 1988).

 

Table 2: Mean agro-meteorological data recorded during two growing seasons.

Growing Season	Temperature (0C)		Relative humidity (%)		Pan evaporation (mm day-1	Total rainfall (mm)
	Max	Min	08:00 hrs	14:00 hrs
2013-14	24.5	10.0	79.5	45.5	2.1	100.5
2014-15	24.3	9.7	82.0	51.2	2.4	160.3

 

 

Plant height (cm)

Effects of genotype were highly significant (P<0.05) on plant height (PLH) in both the growing seasons (i.e. 2013-14 and 2014-15) (Figure 2). PLH ranged from 48.02 to 81.33 in 2013-14 and 48.01 to 83.61 cm in 2014-15. Maximum PLH was recorded in Cli (81.33, 83.61 cm) and Gre (79.89, 79.63 cm) in both the seasons (i.e. 2013-14 and 2014-15), respectively. Both genotypes were statistically alike and differed considerably from the rest of genotypes. Genotype Cor attained lowest PLH (48.02, 48.01 cm) in 2013-14 and 2014-15, respectively. However, it was interesting to note that this genotype was followed by statistically similar values recorded in genotypes Min (49.35, 55.44 cm), P4 (50.78, 54.79 cm), and Ran (53.23, 52.71 cm) in 2013-14 and 2014-15, respectively. These results clearly indicated the existence of genotypic variability among the genotypes (Ali et al., 2007; Khan et al., 2013; Umar et al., 2014).

 

 

Number of pods plant-1

Significant (P<0.05) genotypic variability was found to be present for pods plant-1 (PN) among the different pea genotypes in both the growing seasons (i.e. 2013-14 and 2014-15) (Figure 3). In 2013-14, genotype Cli produced maximum PN (18.64) with a very low or no differences of varieties Gre, Das, Sha, Met, and Fsd due to statistical similar ranks. Lowest PN (15.01) were registered in genotype Ran succeeded by Min (15.10) and all these two genotypes were statistically identical to each other. In 2014-15, as expected, the genotype Cli produced maximum PN (19.34), while genotype Ran produced the lowest PN (13.39). The rest of genotypes indicated similar trends as in 2013-14. The presence of significant genetic variation in pod formation has been reported by Ashraf et al. (2011), and Kosev et al. (2013).

 

Pods plant-1weight (g)

Fresh pods plant-1 weight (PWT) differed significantly (P<0.05) among the pea genotypes in both the growing seasons (i.e. 2013-14 and 2014-15) (Figure 4). In 2013-14, the genotype Cli exhibited maximum PWT (51.83 g) followed by Gre, Das, and Sha with non-significant PWT (51.08, 49.98, 47.14 g, respectively). Minimum PWT was recorded in genotype Cor (40.05 g) which was followed by statistically at par PWT (41.99, 42.19, 42.85, 42.98 and 44.65 g) in PS-40, Ran, Min, Fsd and Met, respectively. Results from the second season (i.e. 2014-15) revealed almost similar results for genotype Cli with maximum PWT (51.90 g). However, it was followed by statistically non-significant PWT in the rest of genotypes except for Fsd and Cor with minimum PWT (41.65 and 39.76 g, respectively). The variation in PWT may be attributed to the inherent capability of some genotypes particularly Cli to produce high number of pods as these traits have close inter-relationship that affect crop yield considerably. Such relationships are discussed in detail in later section. Findings are inter-linked to previously deduced results of Tan et al. (2012) and Khan et al. (2013).

Pod length (cm)

Different pea genotypes designated significant (P<0.05) differences in pod length (PL) in both growing seasons (i.e. 2013-14 and 2014-15) (Figure 5). In 2013-14, maximum PL (11.09 cm) was presented in genotype Cli, however, it was statistically not different to the rest of the genotypes except Min and Cor with minimum PL (8.23 and 9.17 cm, respectively). Almost similar results were obtained in the second growing season (2014-15), where Cli exhibiting maximum (11.01 cm) pod length. Present findings are in accordance with the findings of Ghafoor et al. (2005) and Khan et al. (2013). Both these studies depicted that considerable genetic variation were found to be present in pod length of different pea cultivars.

 

Pod width (cm)

Findings showed huge (P<0.05) contrasts in the pea cultivars for pod width (Pw) in both the growing seasons (2013-14 and 2014-15) (Figure 6). In 2013-14, greatest pod width (2.51 cm) was recorded from Cli pursued by Gre with 2.31 cm for said trait and the two genotypes were measurably indistinguishable however differed really from every single other cultivar. Measurably comparative outcomes for Pw (cm) were significantly different in genotypes Ran, Sha, Cor, Min, Met, and Fsd with Pw 2.21, 1.65, 1.51, 1.61, 1.54, and 1.81 cm, respectively. The narrowest Pw (1.49 cm) was found in genotype Das pursued by P4 with 1.76 cm Pw and the two genotypes were identical to one another. Results relating to second growing season (2014-15) uncovered most extreme Pw (2.67 cm) in genotype. Cli showed measurably similar Pw (2.89 cm) to Gre which differed significantly from every single other genotype. It was trailed by measurably comparative Pw recorded in Sha (2.12 cm), Ran (1.79 cm), and Fsd (1.99 cm). Smallest Pw (1.71 cm) was found in Das that was factually indistinguishable to PS-40, Cor, Met, Min, and Fsd with 1.69, 1.70, 1.69, 1.69 and 1.91 cm Pw, respectively. These outcomes demonstrated that various genotypes indicated heterogeneous differences in Pw being most astonishing in Cli and Gre, while the least in Das. Past researchers like Khan et al. (2013) and Umar et al. (2014) likewise announced dissimilarity in Pw in various genotypes of Pisum sativum.

 

Grains pod-1

Critical contrasts were recorded among the distinctive pea genotypes in regards to GN in both the growing seasons (2013-14 and 2014-15) (Figure 7). In 2013-14, maximum GN (8.02) were recorded in genotype Cli all around intently pursued by Gre, Das, Sha, Ran, and Met with 7.64, 7.12, 6.93, 6.65 and 6.92 GN, respectively. In any case, all these six genotypes did not vary altogether from one another. Statistically alike results were reported for genotypes P4 and Fsd, both delivering 6.33 and 6.51 GN respectively. The least GN (5.19) were recorded in Cor that varied essentially from every single other cultivar aside from Min producing 5.72 GN. In the second growing season (2014-15), the fundamentally maximum GN (7.36) was recorded in Cli, statistically similar pursued by Gre, PS-40, and Das creating 7.07, 6.81, and 6.69 GN, respectively. The genotype Cor recorded least GN (5.56), trailed by factually non-huge qualities in genotypes for example Ran, Min, Fsd, Sha, and Met with 6.04, 5.87, 5.93, 6.01 and 6.03 GN, respectively. These results demonstrated that GN differed significantly among the pea genotypes. Pea cultivar Cli, Gre and Das produced the highest GN as contrasted with different genotypes, while the most minimal GN were recorded in Cor during both the growing seasons (2013-14 and 2014-15), demonstrating differential grain production capability of pea genotypes. Previously researchers Bozoglu et al. (2007), Muhammad et al. (2009), and Khan et al. (2013) furthermore found different GN in various genotypes of Pisum sativum which indicates presence of genetic fluctuation for this attribute in pea germplasm.

 

 

Pod yield (t ha-1)

Exceptionally remarkable variation in PY was recorded among various pea genotypes in both the growing seasons (2013-14 and 2014-15) (Figure 8). In 2013-14, the most elevated PY (5.61 t ha-1) was recorded in genotype Cli which was in all respects intently prevailing by Gre (5.50 t ha-1) and the two genotypes fundamentally contrasted from the remainder of genotypes. These were trailed by Das (4.52 t ha-1), Sha (3.95 t ha-1), and Met (3.38 t ha-1). Genotype Met with 3.38 t ha-1 PY in turn was factually much the same as Fsd, PS-40, and Ran producing PY of 3.31, 3.26, and 2.90 t ha-1, separately. Cor created the least PY (2.78 t ha-1) which was measurably at standard with genotypes Min, Ran, and PS-40. In S2, practically comparable outcomes were gotten. The genotype Cli created essentially greatest PY (6.29 t ha-1) which showed up measurably at standard with Gre (6.28 t ha-1), in any case, both these genotypes were fluctuated fundamentally from the remainder of genotypes.

It was trailed by genotypes Das, Sha and Met with PY of 4.96, 4.19, and 4.04 t ha-1, respectively, however, the last two genotypes were non-significant to each other. Factually comparable outcomes were likewise seen in Fsd and P4 with PY 3.52 and 3.44 t ha-1, individually. Be that as it may, genotype S-40 was likewise factually like Ran (3.19 t ha-1). The genotype Cor and Min exhibited the most reduced PY (2.62 and 2.79 t ha-1, separately) and varied from the remainder of genotypes. These outcomes uncovered impressive contrasts among pea genotypes for PY. Comparable outcomes were cited by Arshad et al. (2011) and Khan et al. (2015), who additionally discovered Cli as stature pea yield genotype among the various studied genotypes. These outcomes are fairy supported by Jilani (2008), Muhammad et al. (2009) and Khan et al. (2013) who enlisted huge contrasts in pod yields of pea germplasm.

Conclusions and Recommendations

This study concluded that there exists significant phenotypic diversity among the pea genotypes for plant growth, yield, and yield contributing traits under the growing conditions of D.I. Khan, Khyber Pakhtunkhwa, Pakistan. Findings revealed that genotype Cli very closely followed by Gre were promising varieties among tested genotypes in enhancing the yield of peas substantially.

Novelty Statement

There exists significant phenotypic diversity among the pea genotypes for plant growth, yield, and yield contributing traits under the growing conditions of D. I. Khan, Khyber Pakhtunkhwa, Pakistan.

Author’s Contribution

Tehseen Ali Jilani: Conducted the research.

Muhammad Saleem Jilani, Hasnain Saleem and Javeria Sherani: Reviewed the manuscript.

Kashif Waseem: Helped in preperation of graphs.Muhammad Sohail Khan: Wrote and reviewed the manuscript.

Abdul Manan: Approved the final draft.

Rashid Jawad: Helped during research and method.

Sami Ullah: Helped in interpretation of results.

Conflict of interest

The authors have declared no conflict of interest.

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