Path Coefficient Analysis Studies Research Articles

Association and Path Coefficient Analysis Studies in Potato (Solanum tuberosum L.) Genotypes at Adet, Northwestern Ethiopia

The experiment was conducted during main rain fall season from June to October, 2018 in Adet, Ethiopia with the objective of estimating the correlation and identifying the direct and indirect effect of yield contributing traits on potato crop. 36 potato genotypes were evaluated in simple lattice design in two replications. The analysis of variance revealed that highly significant (p<0.001) difference among potato genotypes for all traits except average stem number. Total tuber yield was positively correlated with days to maturity, plant height, average stem number, marketable, unmarketable, total tuber number and marketable yield while it was negatively correlated with late blight severity percentage at both phenotypic and genotypic level. High correlation was observed between total tuber yield and marketable tuber yield (rp=0.982 and rg=0.986) followed by total tuber number (rp=0.735 and rg=0.789), and marketable tuber number (rp=0.700 and rg=0.737). Days to flowering, days to maturity, average stem number, marketable and unmarketable tuber number, starch content percentage, average tuber weight, and unmarketable tuber yield had positive direct effect on the total tuber yield at both genotypic and phenotypic level. Highly direct effect on total tuber yield was observed by marketable and unmarketable tuber number (3.65 and 1.17 respectively) and average tuber weight (0.56). Therefore, traits with significant positive correlated and direct effect on total tuber yield such as days to maturity stem number, marketable tuber number, marketable tuber yield and average tuber weight should be considered in selection criteria for enhancing tuber yield in potato.

Correlation coefficient and path coefficient analysis studies in Brassica spp. for yield and quality traits

An experiment was conducted with 40 genotypes of Brassica species (Brassica juncea-15, Brasica rapa var. yellow sarson-10, Brassica rapa var. toria-5, Brassica tournefortii-5, Brassica nigra-2 and Brassica carinata-3) in Rabi season 2021-22 College of Agriculture, Jodhpur (Rajasthan). The experiment was put out in randomized block design (RBD) with 3 replications. Correlation coefficient analysis indicated that seed yield/plant had positive significant correlation with days to 50% flowering, days to maturity, plant height and siliqua density of main shoot. The direct effect on seed yield/plant were observed for plant height, number of primary branches/plant, first branch initiation height, number of seeds/siliqua, 1000 seed weight and glucosinolates. The genotypes MYS-172 and MN-2 showed high and low oil content, respectively, whereas, genotype TM309-1 and MBT-4 showed the highest and the lowest glucosinolates, respectively.

Studies on Inter-Relationship and Path Coefficient Analysis for Seed Yield/Plant and Qualitative Traits in Indian mustard (Brassica juncea L. czern and cos)

The present investigation was carried out with ten Indian mustard genotypes in biochemistry laboratory of ICAR-DRMR, Bharatpur, during 2021-22. Analysis of oil, fatty acid profiling and estimation of glucosinolate was done to study the inter-relationship and path coefficient analysis between seed yield and among all nine qualitative traits taken. It is found that the genotypic correlation was higher than phenotypic correlation due to genetic effect. The positive correlation of seed yield/plant is associated at both phenotypic and genotypic levels with palmitic acid, linoleic acid, oleic acid, stearic acid and linolenic acid whereas negatively associated with glucosinolate, erucic acid and eicosenoic acid. Oleic acid was positively correlated with linoleic acid. Path coefficient analysis studies revealed that the high positive direct effect on seed yield/plant was exhibited by linoleic acid, linolenic acid and stearic acid while negative direct effect by erucic acid, glucosinolate, oil and eicosenoic acid on seed yield/plant. Selection of the plants based on these traits would certainly leads to improvement in seed yield.

Character association and path coefficient analysis studies on yield and yield attributing characters in Turmeric (Curcuma longa L.)

The Correlation and path analysis was studied for fresh rhizome yield per hectare and its component characters in 12 diverse genotypes of turmeric during Kharif season of 2014-15, 2015-16 and 2016-17 at Horticultural research Station, Chintapalli. The data recorded on different characters were subjected to work out correlation and path analysis to investigate the association, direct and indirect contribution of various characters on fresh rhizome yield per hectare. The resulted indicated that the strong positive genotypic correlation of plant height and yield per plant with yield per hectare. The dry recovery had a significant positive correlation with plant height, leaf length and leaf area while the significant negative correlation with the number of tillers per plant. The path analysis study revealed that the yield per plant the most important yield per hectare determinant followed by leaf length and leaf area is the another most important yield determinant thus, these characters should be given importance in selection programmes for yield improvement in turmeric.

Correlation and Path Coefficient Analysis Studies on Grain Yield and Its Contributing Characters in Maize (Zea mays L.)

In crop breeding, the selection for yield is made complex because of the quantitative and polygenic nature of the character. This study was undertaken to assess character association and show the contribution of various yield contributing characters in some maize varieties through the help of correlation and path coefficient analyses in order to identify appropriate plant characters for selection to improve maize grain yield. Seventeen maize varieties were sown in a randomized complete block design with three replications in a humid environment of Port Harcourt, Nigeria in 2018 under rainfed condition. Data were recorded for days to 50% anthesis, days to 50% silking, anthesis-silking interval, plant height (cm) and ear height (cm), number of plants per plot, number of plants harvested, number of ears harvested, moisture content (%), field weight (kg), and grain yield (t ha-1). Results showed number of plants per plot, number of plants harvested, number of ears harvested and field weight correlated positively and significantly both phenotypically and genotypically with grain yield. Path coefficient analysis at the genotypic level also revealed field weight and days to 50% anthesis as the characters exerting the highest positive direct effect on grain yield. Therefore, maize grain yield could be improved through indirect selection for these characters.

Study of path coefficient analysis of some quantitative traits in wheat (Triticum aestivum L.)

The present investigation entitled “Study of Path Coefficient Analysis of some Quantitative Traits in Wheat (Triticum aestivum L.)” was undertaken to study the path coefficient analysis for grain yield and its components. A set of twenty genotypes of Wheat were evaluated over two years from 2015-16 to 2016-17 to assess the genetic analysis of these genotypes for yield and its contributing traits over years and environments. Experiment was conducted in randomized complete block with 3 replications and two dates of sowing i.e. 3rd week of November (timely sown) and 1st week of January (very late sown). In the study number of tillers plant-1 showed highest positive direct effect on grain yield plant-1, followed by biological yield plant-1, harvest index, number of grains plant-1, ear weight and number of spikelets ear-1. It means direct selection of these traits may reward. However, days to maturity, plant height, days to 50% flowering, ear head length, peduncle length, 100 grain weight, number of ears plant-1, number of grains ears-1, number of dead tillers plant-1 and number of effective tillers plant-1 recorded negative direct effect on grain yield plant-1. Greater part of indirect effects was recorded via other traits were only such traits viz., biological yield plant-1, number of tillers plant-1, number of effective tillers plant-1/number of ears plant-1, harvest Index, number of grains plant-1, ear weight and number of spikelets ear-1 having high to moderate positive indirect effects. This indicated that these were main contributors to the grain yield.

Genetic Diversity Analysis for Economically Important Traits of Sugarcane (Saccharum officinarum L.) Ratoon Crop

Study on correlation and path coefficient analysis for cane yield and yield related traits in 20 accessions of sugarcane (Saccharum officinarum L.) ratoon crop was conducted in the field of Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad, Pakistan. Analysis of variance indicated highly significant differences (p = 0.01) among the accessions for all the traits as shown in Table 2. Among the traits studied cane weight had positive correlation both at genotypic and phenotypic level with plant height, leaf area, cane diameter, no. of nodes per plant, internodal distance, juice contents dry matter contents and bagasse weight (Table 3). Also cane weight has negative correlation with no. of tillers per plant and no. of millable canes per plant significant at phenotypic level (Table 3). The study of path coefficient analysis for yield related traits depicted that baggas weight exerts maximum direct effect on cane yield followed by juice contents and internodal distance and indirect effects of these traits via each other were also found maximum compared to other traits (Table 4) while Dry matter contents, Leaf area and No. of tillers per plant had negative direct effect on cane yield. Cluster analysis revealed that cluster II ( BF-129, CPF-234, CP-77-400, TRITON and SPSG-26) showed highest values (Table 7) for most of the traits like plant height, leaf area, cane diameter, No. of nodes, juice contents, dry matter contents, bagasse weight and cane weight. The similar trend is also shown by PCA biplot. So best performing sugarcane accessions like cluster II viz BF-129, CPF-234, CP-77-400, TRITON and SPSG-26 if selected for breeding against highly correlated variables of bagasse weight, juice contents and internodal distance with cane weight, can increase our yield qualitatively and quantitatively.

Character association and path co-efficient analysis studies on yield and yield attributing characters in chilli (Capsicum annuum L.)

Character association and path co-efficient analysis studies on yield and yield attributing characters in chilli (Capsicum annuum L.)

Correlation and path coefficient analysis studies for the yiled and its traits in cabbage (Brassica oleraceava.Capitata L.).

Correlation and path coefficient analysis studies for the yiled and its traits in cabbage (Brassica oleraceava.Capitata L.).

Character association and path co-efficient analysis studies on yield and attributing characters in brinjal (Solanum melongena L.)

The correlation studies in thirty four genotypes of brinjal comprising ten parents, twenty one F 1 hybrids and three checks during summer season of 2014 indicated strong positive correlation of primary branches per plant, days to final harvest, flowers per cluster, fruits per cluster, fruit length, average fruit weight and fruits per plant with fruit yield per. However, a significant negative correlation of fruit yield per plant was observed with days to 50% flowering. The path analysis study revealed that the fruits length is the most important yield determinant, because of its high direct effect and indirectly influence the yield through primary branches per plant, days to final harvest, fruits per cluster, average fruit weight and fruits per plant followed by fruits per plant is the another most important yield determinant thus, these characters should be given importance in selection programme for yield improvement in brinjal.

Logistic Regression Models to Aid Selection in Early Stages of Sugarcane Breeding

In sugarcane breeding, visual appraisal is used to select for cane yield among seedlings (Stage I) and non-replicated clonal plots (Stage II). Genotype by environment interaction and interplot competition reduces selection efficiency. Although path coefficient analysis studies identified important yield components for indirect selection, currently there is little integration of that knowledge in models to improve early stage selection. This study demonstrates the use of logistic regression models as a statistical decision support tool that uses simultaneous selection for yield components (stalk number, stalk height, stalk diameter, estimable recoverable crystal (ERC) % cane) to help identify genotypes that produce high yield in non-replicated stages of sugarcane breeding. Data were collected from two Stage I populations grown at the USDA-ARS, Sugarcane Research Station at Houma and LSU AgCenter, Sugar Research Station, St. Gabriel, Louisiana, USA and two Stage II populations grown at Gingindlovu and Empangeni research stations, South African Sugarcane Research Institute, in South Africa. The data were analyzed using the logistic procedure of the statistical analysis system. Genotypes selected using the logistic regression models produced higher yield and larger values for yield components than those not selected. Stalk number was the most influential yield component while ERC% cane was the least. The logistic regression models identified the yield components that contributed significantly to yield for each population. The differences in variability within and among the populations provided guidance as to the precision of selection and therefore could indicate to the breeder the need for a higher or lower selection rate. Higher discriminating ability between selected and rejected genotypes indicated greater precision of selection.

The role of pith, tube, and stalk density in determining sugarcane sucrose content and stalk weight

Selection against pith and tube is one of the major criteria used to eliminate inferior sugarcane (Saccharum spp.) cultivars in early stages of new cultivar evaluation. Understanding the genetic relationships for these traits would facilitate crossing and selection decisions. This study was conducted to determine heritability, genetic coefficient of variation, and the potential for genetic advance by selection for pith, tube, and stalk density. Correlation and path-coefficient analysis studies were conducted to determine the effects of Brix, pith, and stalk density on sucrose content and the effects of stalk volume, tube, and pith on stalk weight. Eighty randomly selected cultivars (four progeny from each of 20 crosses), representing a first clonal stage of a Louisiana sugarcane breeding population, and their parents were planted at St. Gabriel/LA, and yield data were collected in 1986, 1987, and 1988. Pith and tube exhibited large genotype and genotype-by-year variation, whereas variation in stalk density was nonsignificant. Broad-sense and narrow-sense heritabilities were high, moderately high, and low for pith, tube, and stalk density, respectively. Path-coefficient analysis revealed that stalk volume was the major factor determining stalk weight. Tube and pith were factors that decreased stalk weight. As expected, Brix was the single most important factor determining sucrose content, however, high stalk density and low pith were also associated with high sucrose content. Sugarcane breeders should practice stringent selection for low pith across years to increase stalk weight and sucrose content. Since stalk density was effectively increased by high sucrose content and low pith, the use of stalk density in breeding and selection should be avoided. The minimal effect of tube on stalk weight suggests that its use as selection criteria be minimized or dropped.