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Background: The seed yield of chickpea can be improved by selection of superior genotypes on the basis of different yield and yield component traits. These genotypes exclusively utilize in breeding programs. Yield is a complex trait which is affected by several factors, hence, a well-known technique known as principal component analysis was used to identify and minimize the number of traits for effective selection. To obtain efficient recombinants, the identified component traits need to be combined from diverse parents through recombination breeding followed by selection of transgressive segregants. Hence, the present study is envisaged to measure the genetic diversity among genotypes of chickpea. Methods: The experimental material comprised of 40 chickpea genotypes evaluated in randomized block design with three replications. The experimental unit was four rows per plot with 4 m length and spacing between row to row and plant to plant maintained as 30 x 10 cm. NPK (20:40:00) fertilizers was applied as basal doses. The data were recorded for each genotype on nine quantitative traits as per standard methods. Descriptive statistics and PCA analysis was performed by using the statistical package SPSS 16.0 version and cluster analysis was done using the Wards method of hierarchical clustering technique. Result: Out of nine PCs only three PCs exhibited more than 1.0 Eigen value and showed about 73.4% variability. PC1 contributed 28.6% of the total variation and correlated with days to flowering, days to maturity, plant height, first pod height, seeds per pod and number of pods per plant while PC2 explained 21.00% of the total variation and dominated by plant height, first pod height and seed yield. PC3 explained an additional 13.00% of the total variation and dominated by primary branches per plant. Genotype commonly found in more PC, were BG 4016, IPCB 2015-165, IPC 2011-247, GNG2459 and RKG 19-4. Hierarchical clustering technique grouped 40 genotypes into two main clusters (A and B) and nine sub clusters. The present investigation depicted that the chickpea germplasm displayed considerable genetic diversity for most of the traits under consideration. [ABSTRACT FROM AUTHOR]

Background: Among all the pulses, chickpea is the most important rabi crop with high acceptability and wider use in India. More availability of quality seed of improved varieties being made available to the famers is one of the most important factors contributing to better harvest of chickpea in recent years. Therefore, there is urgent need for developing high yielding varieties of chickpea employing sound and effective breeding strategies. The study of variability, correlation and path coefficient analysis for seed yield with other yield contributing characters is of immense importance to get information regarding exercising selections for genetic improvement in chickpea. Background: Among all the pulses, chickpea is the most important rabi crop with high acceptability and wider use in India. More availability of quality seed of improved varieties being made available to the famers is one of the most important factors contributing to better harvest of chickpea in recent years. Therefore, there is urgent need for developing high yielding varieties of chickpea employing sound and effective breeding strategies. The study of variability, correlation and path coefficient analysis for seed yield with other yield contributing characters is of immense importance to get information regarding exercising selections for genetic improvement in chickpea. Result: Genotypes revealed significant wide genetic variation for almost all the quantitative traits. Number of pods plant-1 exhibited highest PCV and GCV. The highest broad sense heritability (h2b) was recorded for days to maturity followed by days to 50% flowering and 100-seed weight. The 100-seed weight, number of pods plant-1, number of seeds pod-1 and primary branches plant-1 had positive genotypic correlation with grain yield. Path coefficient analysis depicted that among the 9 causal (independent) traits; number of seeds pod-1, number of pods plant-1, number of primary branches plant-1, plant height from ground to first pod (cm) and days to 50 % flowering had positive and directly influence on grain yield. Therefore these traits can be taken into consideration while exercising selection for grain yield in chickpea. [ABSTRACT FROM AUTHOR]

This note presents a method for the numerical approximation of simple zeros of a non-linear equation in one variable. In order to do so, the method uses an ellipse rather than a tangent approach. The main advantage of our method is that it does not fail even if the derivative of the function is either zero or very small in the vicinity of the required root. (Contains 1 table.)

Background: Chickpea (Cicer arietinum L.) is cultivated in almost all parts of world covering more than 50 countries spread over Asia, Africa Europe, Australia, North America and South America countries and is the second most important food legumes crop after common bean (Phaseolus vulgaris L.). Chickpea has played a major role in realization of pulse Revolution in india making the country near self-sufficient in pluses. Gram is extensively grow in india. Due to its high nutritional value and its ability to fix atmospheric nitrogen, its more widely cultivated rabi pulse crop. The gram pod borer Helicoverpa armigera (Hubner) is most important pest of chickpea. Many pesticides were so far tested against this pest but due to over use of these pesticides resistance, residue and resurgence problems arises, beside destruction of natural enemies. Methods: To determination of per cent pod damage and yield of chickpea due to different larval density of H. armigera is an important tool to reduce the cost of cultivation by avoiding the unnecessary use of pesticides. Therefore, a pot experiment was conducted in arranged in a completed randomized design with four replications. The pots were placed under natural field conditions and take observation at Research farm, Rajasthan Agricultural Research Institute, Durgapura, Jaipur during 2015-16 and 2016-17. Result: The results revealed that least per cent pod damage (29.05, 24.78%) was recorded when the larval population was one per plant, while the maximum pod damage (64.55 and 67.76%) was recorded during 2015-16 and 2016-17, respectively. The simple liner correlation analysis indicated that there was a significant positive correlation (r= 0.989 and 0.999) between the larval density and per cent pod damage. Further, a significant correlation was noticed between larval density and number of healthy pods per plant, reduction in yield, yield per plant, total number of pod and damaged pods were -0.964, -0.976; 0.98, 0.986; -0.98, -0.986; 0.117, 0.126 and; 0.985 and 0.992, respectively during 2015-16 and 2016-17. [ABSTRACT FROM AUTHOR]