Characterization and correlation analysis of economically important parameters of lentil exotic germplasm

The basic aim of this study is to evaluate the exotic lentil germplasm (BIGMP LIEN-MH-18) received from ICARDA. Economically desirable characters were studied and correlated to select the genotypes for the targeted breeding programme. Thirty-six lentil exotic entries were studied. The exotic genotypes 36102 and 36108 yielded 665 and 625 kg/ha respectively similar to our local recommended check (Punjab Masoor-09) that produces 884 kg ha -1 seed yield. There were high differences for the traits that were studied. The number of pods per plant, plant stand and first pod height were significantly (P < 0.05) associated with yield. The plant height was non-significantly associated with yield while number of branches was negatively and non-significantly associated with yield. Disease attack was negative and highly significant. This association of the characters could be used in future breeding programs to enhance the yield potential for exploiting the production of the lentil crop.


INTRODUCTION
Pulses contain high protein content and good amino acid balance in several forms worldwide; therefore, they are important source of protein and necessary in routine life (Sharma et al., 2014).Lentil is one of the important pulse crops and sometimes it is called poor man's meat (Bhatty, 1988).It is a bushy annual autogamous diploid (2n=2x=14) legume crop.Its family is Fabaceae.It is generally grown as rain fed crop during winter season.Its protein content ranges from 22 to 34.6% (Sharma et al., 2014).Ash, crude fiber, starch, amylase and total carbohydrates contents in lentil are 3. 1, 4.6, 44.3, 36.1 and 63.1% respectively (Bhatty et al., 1976).It also contains 420 cal.per 100 g gross energy (Sahi et al., 2000).Lentils are lower in anti-nutritional factors such as haemoglutinins, oligosaccharides and favogens compared to most other legumes.The area of the world under lentil production is 2.5 million ha and the contribution of Indian sub-continent (India, Pakistan and Bangladesh) is about 38% (Composition and quality).Its local name is Masoor in Pakistan and mainly grown in Gujranwala and *Corresponding author.E-mail: aqsatahir24@yahoo.com.
Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution License 4.0 International License Rawalpindi divisions in Punjab, Swat and Bajaur in North West frontier province of Pakistan (Hussain et al., 2008).In Pakistan, the area under lentil cultivation is 14.2 thousand ha with production of 6.4 thousand tonnes and average yield is 5.23 kg per ha during 2016-2017 (Anonymous, 2016).Lentil has been cultivated since 8000 BC, but it remained an under exploited crop, compared to other early domesticated crops.The principal aim of lentil production is to gain high yield (Karadavut, 2009).For any crop improvement program, systematic study and evaluation of germplasm is of great importance for agronomic and genetic improvement of the crop.The aim of the study was to identify high yielding genotypes that could be further used in hybridization programs.

MATERIALS AND METHODS
Thirty six genotypes of lentil, obtained from ICARDA, were used.Pb.M-2009, a local check variety, was used in the experiment as a check.This experimental study was conducted under irrigated condition at Ayub Agricultural Research Institute (AARI), Faisalabad during 2017-2018.There was no supplemental fertigation used in this experiment.Randomized Complete Block Design with 2 replications was used in this experiment.Each plot consisted of two rows with 30 cm width and 4 m length.The experiment was sown in the 1st week of November 2017 and was ready for harvest in the 2nd week of April, 2018.Five plants of each genotype were selected randomly from each replication at maturity to record the data on following pre and post-harvest traits; example plant stand, plant type, prominent property, 50% flowering, disease attack, plant height, number of branches, 1st pod height, number of pods per plant, seed testa, cotyledon color, seed shape and seed yield were recorded for statistical analysis.

Statistical analysis
The recorded data were subjected to analysis of variance following Steel et al. (1997) to estimate the genetic variability in the breeding material.Least significant difference Test (LSD) was used to compare the means of accessions as used by Williams and Abdi (2010).Correlation among various attributes was computed according to Kown and Torrie (1964).

RESULTS AND DISCUSSION
The genotypes 36102 and 36108 giving the yield of 665 and 625 kg ha -1 were comparable with the local check (Pb.M-09) that gave 884 kg ha -1 seed yield.There was a high variation among the genotypes for the traits used for the study to evaluate them (Table 1).The plant stand and number of pods per plant significantly correlated with the seed yield.
Disease attack was negatively and non-significantly (P < 0.05) correlated with plant stand (Table 2).The plant stand and number of pods per plant are the major yield contributors.Sufficient vegetative growth and branching provide an opportunity to the plants to provide sufficient number of pods and become responsible for high yield.Asghar et al. (2012) reported on the basis of their study that number of pods per plant were highly significantly and positively correlated with seed yield.Singh et al. (2009) studied correlation and path coefficient analysis among different characters of lentil genotypes and concluded that as seed size increases, the number of seeds per pod and pods per plant decreases noticeably that adversely affect the seed yield.Khan et al. (2001) concluded that seed yield had significantly positive correlation with pod plant, number of branches per plant and number of seeds per pod.Pods per plant and number of seed per pod can be used while selecting lentil varieties for this zone.Plant height also showed very interesting correlation: reducing plant height meant more number of seeds per pod and biological yield.However, early maturing, shorter varieties with more number of branches per plant and number of seed per pod may be considered an index for selection in the germplasm under study for yield.Begum and Begum (1996) reported the positive and significant correlation of plant height to seed yield in lentil.Abo-Shetaia (1997) confirmed these results later.Rajput and Sarwar (1989) showed highly positive significant correlation of number of pods per plant and seed yield.Tyagi and Sharma (1985) and Begum and Begum (1996) confirmed the results of highly positive and significant (P < 0.01) correlation of biomass to seed yield in lentil.
The disease attack was highly and negatively correlated with the seed yield.Furthermore, disease attack causes the stunted growth of the plants and poor pod and seed formation.Therefore, negative association of these traits with the seed yield can be expected (Table 3).Plant height was significantly associated with plant stand while non-significantly associated with disease attack.Number of branches per plant was negatively and highly significantly correlated with plant stand and plant height but it was negatively and non-significantly associated with disease attack.There was negative and non-significant association of number of pods with disease attack and plant height.Number of branches was highly significantly associated while plant stand was negatively and significantly associated with number of pods.First pod height had negative and highly significant association with number of branches and number of pods, highly significant association with plant height while nonsignificant association with all other characters.Normally, it is not possible for the exotic germplasm to compete with the locally well-adapted genetic material but it provides some unique and useful genes like its bold seededness for incorporation into desirable genetic background.The genotypes 36102 and 36108 were almost at par with the check in yield but can be used as a diverse parent in the breeding programme to broad the genetic base as such germplasm has been used successfully in the earlier research work for developing varieties resistant to abiotic stresses (Ali et al., 1991).Out of 36 exotic genotypes plant types 21 entries were

Table 1 .
Mean values of different traits of exotic lentil germplasm studied during 2017/2018 cropping season under natural environmental conditions at PRI, AARI, Faisalabad.The acquisition of new germplasm and its evaluation is essential to select the new useful genotypes in the breeding program to incorporate desirable genes into desirable genetic background for the development of new

Table 3 .
Mean values of different traits of exotic lentil germplasm studied during 2017/2018 cropping season under natural environmental conditions at PRI, AARI, Faisalabad.