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Silver pomfret (Pampus argenteus) is an important economic fish for aquaculture industry in China and Southeast Asian countries.The relationship between twelve morphological traits of P. argenteus were studied at different growth stages [60-, 90-, 120-, and 360-days post hatching (dph)] by usingcorrelation, path analyses, and multiple linear regression tools. The results showed that coefficient of variation of the body weight and trunk length traits remained stable and at a high level across all age groups (all above 20%), while other traits were the opposite. The body length and tail length traits had great direct effect on the body weight of P. argenteus at the first three growth stages (60, 90, and 120 dph). However, body length and body height traits had great direct effect in 360 dph, and the direct effect coefficient of caudal length was negative, indicating that the trait had a negative effect on body weight. Multiple linear regression analysis between morphological traits and body weight indicated that R2 was greater than 0.84 across all age groups (P < 0.05).The optimal multiple linear regression equations, as determined with stepwise regression, were constructed with morphological traits as independent variables and body weight as dependent variables.These results elucidated the linear relationship between the body weight and various main morphological traits of P. argenteus at different growth stages. In actual production, during mass selection of P. argenteus with body weight as the main objective, the recommended as auxiliary selection traits were the body length, body height, tail length, and caudal length traits. These results can provide a reference basis for the measurement of target traits for the selective breeding of new varieties of P. argenteus. [ABSTRACT FROM AUTHOR]

The present study was carried out at Sararood Dryland Agricultural Research Institute (DARI), during the growing season 2011-13 under rain-fed and irrigated conditions to investigate association among yield and yield contributing characters and to determine the suitable selection criteria in durum wheat breeding for higher yields. Field experiments were performed in a triplicated randomized block design. Combined analysis of variance revealed significant differences between lines for the most of traits studied. Traits of the number of fertile stems (NFS), number of grains per spike (NGPS) and thousand-kernel weight (TKW) were not affected by conditions * lines interaction effects. According to the stepwise regression analysis NFS and NGPS entered in the model and were recognized as the most effective traits on durum wheat grain yield under both irrigated and rain-fed conditions. Whiles NFS and NGPS have been recommended as selection criteria for increasing yield of durum wheat only in the rain-fed condition based on the result of path analysis and indirect effects. Advanced Wheat Line (ADWL)-3, ADWL-8, ADWL-10 and ADWL-7 are suggested useful considering production of desirable NFS, and ADWL-12 and ADWL-16 considering production of desirable NGPS, for further breeding programs and commercial release in the rain-fed condition. Days to physiological maturity (DM) has been recommended as a selection criterion only in the irrigated condition. ADWL-5 and ADWL-1 were selected considering maximum number of DM whiles these lines can adjust their buffered state in response to environmental fluctuations in such a way that they give maximum economic grain yield. [ABSTRACT FROM AUTHOR]

Quality traits play an important role in sugarcane clonal selection programs. The present investigation was carried out to study the association of quality traits with cane yield to establish an appropriate selection strategy based on quality characters. Sixteen sugarcane genotypes comprising two check cultivars were studied at Sugar Crops Research Institute Mardan, Khyber Pakhtunkhwa (KP), Pakistan. Positive phenotypic and genotypic correlations were observed for all the traits with cane yield (t ha-1) except purity %. Similarly brix % and polarized sugar % showed highly significant and positive correlation with sugar recovery % at genotypic (0.66**, 0.74**) and phenotypic (0.67**, 0.79**) levels. Highly significant correlation of brix % with polarized sugar % at genotypic (1.00**) and phenotypic (0.95**) levels were observed. Path analysis showed that highest positive direct effect on cane yield (t ha-1) is exerted by sugar recovery % at genotypic (0.42) and phenotypic (1.94) levels. It is suggested that the quality parameters should be taken in to consideration in clonal selection program for evolving improved sugarcane genotypes. Moreover the genotypes (MS-92-CP-99, MS-2000-Ho-360, MS-2003-HS-274 and MS-91-CP-523) with high cane yield and sugar recovery should be evaluated further [ABSTRACT FROM AUTHOR]

Yield gaps in agronomic crops are associated with grain number and per unit grain weight. These yield contributing components are interrelated and have compensatory effects on yield. Path coefficient analysis quantifies the direct influence of one yield component upon the other and allows for the separation of correlation coefficients into direct and indirect component effects with respect to various management options. Pearl millet fields with differing planting times (3rd week of June, 1st week of July, 3rd week of July, 1st week of August), with intra-row spacing (10 cm, 15 cm, 20 cm) and nitrogen rate (0, 150, 200, 250 kg ha-1) in semi-arid (Faisalabad) and arid (Layyah) areas of Punjab, Pakistan were used during 2015-16 to examine relationships between yield and yield contributing components via Pearson correlation and path analysis. Correlations of kernels panicle-1 and kernel weight panicle-1 to pearl millet yield were more positive and had strong significance (P= 0.001) at both locations. Direct effects of panicle m-2 and kernel weight panicle-1 on grain yield were found at both locations, however, indirect effects of kernels panicle-1 on millet yield via kernel weight were higher at Faisalabad than Layyah (0.63). Kernels per panicle and kernel weight were positively associated with grain yield of pearl millet at both locations. Row spacing, and nitrogen regimes had higher indirect effects of kernels panicle-1 on millet yield via kernel weight than planting time study. Similarly, kernel weight panicle-1 showed higher yield compensation with intra row spacing and nitrogen variation than with planting time and row spacing changes. In conclusion, plant population per unit area and kernel grain weight are the important yield compensation indicators in pearl millet crop under optimum management options. [ABSTRACT FROM AUTHOR]

Cotton (Gossypium hirsutum L.) is one of the most important plants worldwide because of its fiber that is used as raw material for the textile industry. Since the dyes used in dyeing process negatively affect the environment, many people prefer to use natural colored cotton products. The objective of this study was to establish the inter-relationship and direct and indirect effect of various quality traits on seed cotton yield in colored cotton genotypes. The F3 and F[sub 4] generations of the cross between Carmen (white) and Devetüyü-176 (brown fiber) were used for selection process in terms of seed cotton yield per plant and fiber color. The measured quality traits in the selected genotypes from F3 and F[sub 4] generations were micronaire, fiber strength, fiber length, uniformity ratio, short fiber index, fiber elongation. Phenotypic correlation and path coefficients were calculated separately for each generation. As results of the correlation analysis, seed cotton yield was not negatively associated with fiber quality properties. It may be concluded that the selection for seed cotton yield and fiber color should be applied in early generations and fiber quality properties of the selected promising colored cotton genotypes can be determined in further generations of Carmen x Devetüyü-176. [ABSTRACT FROM AUTHOR]

Cotton (Gossypium hirsutum L.) is one of the most important plants worldwide because of its fiber that is used as raw material for the textile industry. Since the dyes used in dyeing process negatively affect the environment, many people prefer to use natural colored cotton products. The objective of this study was to establish the inter-relationship and direct and indirect effect of various quality traits on seed cotton yield in colored cotton genotypes. The F3 and F4 generations of the cross between Carmen (white) and Devetüyü-176 (brown fiber) were used for selection process in terms of seed cotton yield per plant and fiber color. The measured quality traits in the selected genotypes from F3 and F4 generations were micronaire, fiber strength, fiber length, uniformity ratio, short fiber index, fiber elongation. Phenotypic correlation and path coefficients were calculated separately for each generation. As results of the correlation analysis, seed cotton yield was not negatively associated with fiber quality properties. It may be concluded that the selection for seed cotton yield and fiber color should be applied in early generations and fiber quality properties of the selected promising colored cotton genotypes can be determined in further generations of Carmen x Devetüyü-176. [ABSTRACT FROM AUTHOR]

Osmotic adjustment is an important physiological mechanism to sustain plant growth and productivity under drought stress. Plants maintain their turgor potential by accumulating osmolytes which decrease the osmotic potential. Present experiment on traits association and path analysis was conducted during 2012-2013, under two environments (control and drought stress). This study provided insight into correlation among six physiological and four growth traits and their cause and effects were determined. The traits proline, glycine betaine and sugar were observed to have highly significant positive correlations with osmotic adjustment, both at genotypic and phenotypic levels under drought stress. Path coefficient analysis study under two diverse (control and drought stress) environmental conditions revealed that the traits viz. shoot length, root length, fresh root weight, sugar and glycine betaine demonstrated the differential behavior for osmotic adjustment. Positive direct effects observed by shoot length (1.1053), root length (1.8386), fresh root weight (0.4742), sugar (3.3994) and glycine betaine (1.1224) on osmotic adjustment under drought stress. The direct effects convinced that the selection on the basis of root length, sugar and glycine betaine traits was considered of great importance for cultivar development with considerable drought tolerance at early growth stage. [ABSTRACT FROM AUTHOR]