Statistical Methods For Agricultural Workers

Forty nine genotypes of wheat were evaluated for 12 quantitative and one quality traits during 2010-11. The experiment was conducted in randomized complete block design with three replications at Crop Research Centre, Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut. The mean, range, genotypic and phenotypic coefficient of variation, heritability in broad sense, genetic advance correlation and path analysis were analyzed. Plant height, number of productive tillers per plant, spike length, 1000-grain weight, biological yield per plant and harvest index were significant and positive correlated with grain yield per plant. The phenotypic and genotypic path coefficients exhibited high positive direct contribution of number of productive tillers per plant, plant height, harvest index and 1000-grain weight towards grain yield.The positive indirect effect of plant height on grain yield was registered via days to maturity, number of spikelets per spike, 1000-grain weight and biological yield per plant. Number of productive tillers per plant revealed contribution on grain yield via number of grains per spike, 1000 grain weight, biological yield per plant and harvest index revealing that indirect selection of these characters would be effective in improving grain yield per plant. Higher genotypic coefficient of variance along with high heritability and genetic advance for grain yield per plant, plant height, number of spikelets per spike, number of grains per spike and 1000-grain weight would also be of great use for indirect selection for improvement in yield per plant.

Character association and path coefficient analysis in wheat(Triticum aestivum L.)

Genetic polymorphism was investigated among nine s pring wheat genotypes, differing in grain protein c ontent, including C-306M10 ( mutant of drought tolerant va riety C306), DI 8, DI 9, DI 16, DI 20, DI 716, DI 7 17, DI 728 (near isogenic lines) and HGPC (from Wheat x R ye crosses) using 55 RAPD primers. Out of 55 primer s used, only 36 amplified and generated 2(OPG08, OP D0 5) and 12 (OPD02 ) bands. A total of 342 amplified p were observed, of which 168 were polymorphic (49.12 %) while 174 were monomorphic. The primer OPC-05 aOPC-07 revealed 92.86% and 80.00% polymorphism, respectively and t hese primers were most useful in characterization o f nine wheat genotypes included in this study. The primer OPG-08 showed no polymorphism. It is concluded that the primers OPC -05 and OPC-07 were very effective in distinguishing wheat genotypes in the present study. Twenty six RAPD primers produced a t otal of 48 unique bands for high protein content that were either present o r absent in HGPC a-high grain protein genotype and thus can be used in wheat improvement through marker-assisted select ion (for the bands which are unique by their presen ce). Data (RAPD analysis) were used to generate the similarit y coefficients using ‘siMqual’ subprogram of softwa re NTSYS-PC. The similarity coefficient values ranged from 0.97(DI8 and DI9) to 0.68 (DI9 and HGPC), indicating high genetic variability among the selected wheat genotypes. The cluster analysis and principle component analysis broadly divided the wheat genotypes into two groups and sho wed that DI 9 and HGPC were most divergent genotype s.

/pdf/rapd-analysis-for-genetic-polymorphism-in-bread-wheat-1cs1o12zcn.pdf

RAPD analysis for genetic polymorphism in bread wheat (Triticum aestivum L. Em Thell) genotypes varying for grain protein content

The study was carried out with 3 bread wheat variet ies (resistant KateA-1, sensitive Sultan 95, and mi dle resistant Golia) which are different response to drought. It was aimed to determine changes of some yield and qu ality characteristics in the wheat varieties with differe nt seed size in the study. Artificial drought stres s was created by chemical desiccant application (potassium chlorate with %4) after 14 days to heading of varieties, and productions of undersized seeds were achieved in 2009-2010 growing season. Undersized seeds and normal seeds were sif t d through sieves of different sizes, and different seed and e ndosperm sizes (control are over 2.5 mm, 2.0 mm and under 2.0 m, desiccants are over 2.0 m and under 2.0 m) were gen rated. Regarding of the results it was shown that variety KateA-1 that is resistant to drought gave better results th an the others in different endosperm and seed sizes . To gather with decreases in seed size was shown reduces in charact ers such as grain yield, plant height, spike length , protein content, wet gluten content of the varieties. Gluten indexes values increased by decreases in grain size. No im p rtant statistical effects of seed size on number of spikelets per spi ke, number of grain per spike, grain weight per spi ke, number of tillers per plant, number of fertile tillers per plant, har vest index, spike index, thousand kernel weights an d test weight were found. Among the desiccant treated seeds, the highe st rain yield mean was obtained from seeds over 2. 0 mm sieve of the varieties. In addition, it was shown that they gave results as well as control seeds over 2.5 mm a nd 2.0 mm sieve for the characters. According to results of the study, it is said that there is no inconvenient in the use a seed of grain over 2.0 mm sieve.

/pdf/effect-of-endosperm-and-seed-size-on-some-yield-and-quality-4tx84ydvmx.pdf

Effect of endosperm and seed size on some yield and quality characteristics of wheat (triticum aestivum l. em thell)

The present experiment has been designed to study the correlation and path coefficient analysis to identify the important character(s) for selection under different environmental conditions. The fifty durum wheat genotypes were grown in simple randomized block design experiment (RBD) as timely and late sowing for two years. The estimates of genotypic correlation coefficients were higher in magnitude than the estimates of phenotypic correlation coefficients for almost all the character combinations in all the environments. The grain yield showed significant and positive association with tiller number, biological yield and harvest index in all the environments; with plant height in E III and E IV; with days to maturity and 100 grain weight in E IV only. Path coefficient analysis identified biological yield and harvest index as most important characters which not only showed highest direct effect towards grain yield but almost all other character also showed indirect contribution towards grain yield via these two characters.

Character association analysis in durum wheat (Triticum durum Desf.)

Genetic variability, character association and path analysis between yield and its contributing characters were studied in forty genotypes of durum wheat. Hignly significant differences among genotypes for all the characters studied. High phenotypic and genotypic coefficients of variation coupled with high heritability and high genetic advance as % mean for spike length, grain yield, harvest index and grains per spike indicate the predominance of additive gene effects in controlling these characters. Correlation path analysis revealed that biological yield and harvest index were the most important characters for realizing improvement in grain yield.

Genetic variability, character association and path analysis of yield and its component characters in durum wheat

Progenies raised from bigger seeds of the same genotype were taller, had more leaves, more tillers and higher grain yield than their small seeded counterparts. Differences during growth period between seed categories were also recorded for leaf area, number of leaves, tillering and plant height at different growth stages. Higher grain yield resulted mainly from a greater number of heads on plants grown from large seeds.

Effect of seed size on growth and yield traits in durum wheat (Triticum durum L.).

Forty genotypes of durum wheat were evaluated for eleven characters to quantify the genetic diversity existing them by using Mahalanobis D2 statistic. The genotypes grouped into six clusters. Among the eleven quantitative characters studied, tiller number contributed maximum (10.97%) towards divergence followed by biological yield (10.13%), days to maturity (9.87%), days to heading (9.67%), grains per spike (9.59%) and harvest index (9.10%), Cluster I had minimum days to heading, while cluster V had minimum days to maturity and cluster III had maximum spikelets per spike, grains per spike, grain yield, biological yield and harvest index. The genotypes from cluster III and VI, which have high and low cluster means for majority of the characters are suggested as parents for hybridization.

Rajesh Kumar Sharma

Papers

Genetic variability, character association and path analysis of yield and its component characters in durum wheat

Effect of seed size on growth and yield traits in durum wheat (Triticum durum L.).

Genetic diversity analysis in durum wheat (Triticum durum Dest.)