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71.
Cr3+ sorption on strong acid exchanger Amberlyst-15(H+) is studied as a function of time and temperature using CrCl3.6H2O and [Cr4(SO4)5(OH)2] solutions. The rate is found to be governed by a mixed diffusion for both the solutions and faster for Cl1? solution than SO4 2?. The exchange capacities are found to be higher for Cl1? system than SO4 2?. From the rate constant values, the energies of activation are calculated using the well-known Arrhenius equation. Equilibrium data is explained with the help of the Langmuir equation. The Langmuir parameters are also found to be higher for exchange from the chloride solutions. Various thermodynamic parameters (??Ho, ??So, and ??Go) for Cr3+ exchange on the resin are calculated. The ??Go values are found to be negative while ??Ho and ??So are positive for both the Cr3+/Cl1? and Cr3+/SO4 2? systems. It is suggested that in case of Cl1? solutions, the metal is exchanged as Cr3+, while in case of SO4 2? solutions, the metal exchanging specie is CrSO4 +.  相似文献   
72.
The study was aimed to investigate the influence of animal age, post‐slaughter chilling rate, and aging time on meat quality of M. longissimus dorsi (LD) of water buffalo (Bubalus bubalis) and humped cattle (Bos taurus indicus) bulls. After slaughtering, one side of carcasses was subjected to rapid chilling (RC) (0 ± 2°C) and other side was hanged in controlled room temperature (25 ± 2°C) for 3 hr, then allowed to the chiller (0 ± 2°C). The meat quality traits were analyzed at 1, 7, and 14 days of storage. It was noted that rapidly chilled carcasses from the younger animals of both species missed the ideal pH/temperature window, which affects the toughness of the meat. Buffalo meat presented higher shear force, color L* values, and lower b* value as compared to the cattle meat. Moreover, meat shear force values decreased while all color coordinates and cooking loss values increased with lengthening the storage time in both age groups of cattle and buffalo. In conclusion, the tenderness of cattle meat was superior to that of buffalo and RC adversely affect the shear force values of young cattle and both age groups of buffalo bulls.  相似文献   
73.
Tropical Animal Health and Production - This study examined the analysis of personal and production performance of broiler farming in 10 cities of central Punjab (Lahore, Sheikhupura, Kasur, Okara,...  相似文献   
74.
A field experiment was conducted over two years to evaluate the gas exchange, water relations, and water use efficiency (WUE) of wheat under different water stress and nitrogen management practices at Crop Physiology Research Area, University of Agriculture, Faisalabad, Pakistan. Four irrigation regimes and four nitrogen levels, i.e., 0, 50, 100, and 150 kg N ha?1 were applied in this study. The photosynthetic gas exchange parameters [net carbon dioxide (CO2) assimilation rate, transpiration rate and stomatal conductance] are remarkably improved by water application and nitrogen (N) nutrition. Plants grown under four irrigation treatments as compared with those grown under one irrigation treatment average stomatal conductance increased from 0.15 to 0.46 μ mol m?2s?1mol during 2002–2003 and 0.18 to 0.33 μ mol m?2s?1mol during the year 2003–2004 and photosynthetic rate from 9.33 to 13.03 μmol CO2 m?2 s?1 and 3.99 to 7.75 μmol CO2 m?2 s?1 during the year 2002–2003 and 2003–2004, respectively. The exposure of plants to water and nitrogen stress lead to noticeable decrease in leaf water potential, osmotic potential and relative water content. Relative water content (RWC) of stressed plants dropped from 98 to 75% with the decrease in number of irrigation and nitrogen nutrition. The higher leaf water potential, and relative water contents were associated with higher photosynthetic rate. Water use efficiency (WUE) reduced with increasing number of irrigations and increased with increasing applied nitrogen at all irrigation levels.  相似文献   
75.
Abstract

Canola (Brassica napus L.), is the most important oilseed crop due to high oil contents and low concentration of erucic acid and glucosinolates. In Pakistan, oil seed production is not sufficient to fulfill the needs of the country. Thus, the planned experiment was aimed to evaluate the performance of different canola cultivars i.e. Faisal Canola, Pakola, PARC Canola hybrid and Rainbow at grown under various soil applied boron (B) levels viz., 0, 1, 2?kg ha?1 under a rainfed environment. The experiment was laid out in randomized complete block design with four replications. Among the canola cultivars, the maximum seed oil contents were recorded in cultivar ‘Pakola’ whereas, higher linolenic acid and protein were recorded in cultivar ‘Faisal canola’ as compared to other cultivars. A synergistic effect was found between various levels of B and quality parameters of the canola seed; as higher concentration of oil contents were found when B was applied 2?kg ha?1. Conversely the linolenic acid showed the antagonistic behavior with the various B levels. On the other hand, protein contents, oleic acid and erucic acid revealed non-significant differences under different B application rates. In conclusion, the cultivar ‘Pakola’ provided the highest oil content when the B was applied at 2?kg ha?1; the low concentration of unsaturated fatty acid was observed in ‘PARC canola’ cultivar in the Pothwar region of Punjab, Pakistan.  相似文献   
76.
Limited water availability is a severe threat to the sustainability of crop production. Exogenous application of glycinebetaine (GB) has been found very effective in reducing the adverse affects of water scarcity. This study was conducted to examine the role of exogenous GB application in improving the yield of hybrid sunflower (Helianthus annuus L.) under different irrigation regimes. There were three levels of irrigation: Control (four irrigations), three irrigations (irrigation missing at budding stage) and two irrigations (irrigation missing at budding and grain formation stage) in the experiment. While GB was applied exogenously at 100 mM GB each at budding and grain formation stages, the Control treatment did not receive any GB application. Data regarding yield, yield components and quality parameters showed that water stress reduced the head diameter, number of achene per head, 1000-achene weight and yield. Nonetheless, it was significantly improved by the exogenous GB application. Among the qualitative characteristics, protein contents were significantly increased by water stress at different growth stages but were reduced by exogenous GB application. Whilst oil contents were reduced by drought at different stages, GB application, however, did not ameliorate the negative effect of drought stress on achene oil contents. The effects of water stress and foliar application of GB were more pronounced when applied at vegetative stage than at the reproductive stage. Moreover, exogenous GB application was only advantageous under stress conditions.  相似文献   
77.
For examining the probability of increase in the occupation ratio of inoculated rhizobium in nodules, various Rj-soybean cultivars including the Rj 2 Rj 3 Rj 4-lines of soybean were grown in a field of the Kyushu University Farm. Bradyrhizobium japonicum USDA110 that carries uptake hydrogenase (Hup+) was used as an inoculum. The relative efficiency of nitrogen fixation generally increased by the inoculation. However, there were no significant differences in the effects among the genotypes of the host plants. The occupation ratio of serogroup USDA110 in the nodules on the taproot of the inoculated plants was in the range of 77–100%, suggesting that the B. japonicum strain USDA110 infected taproots immediately after inoculation. The occupation ratios in the nodules on the lateral roots were 53–67, 40–86, 63–83, and 62–77% in inoculated plants of the non-Rj-, Rj 2 Rj 3-, Rj 4-, and Rj 2 Rj 3 Rj 4-genotypes, respectively, and they decreased in all the genotypes with the progression of growth. At the time of the first sampling, the occupation ratios on the lateral roots of these Rj 2 Rj 3 Rj 4-genotypes showed values intermediate between those of IAC-2 (Rj 2 Rj 3) and Hill (Rj 4) , which were the parent cultivars of the Rj 2 Rj 3 Rj 4-lines, B340, B349, and C242. The reduction in the occupation ratio of the serogroup USDA110 for about 1 month after the first sampling was the lowest (0.13–0.16) in the Rj 2 Rj 3 Rj 4-genotypes, excluding B349, followed by the non-Rj- and Rj 2 Rj 3-genotypes and highest (0.52–0.69) in the Rj 4-genotypes, excluding Hill. Therefore, it was considered that the population of compatible rhizobia with host soybean plants increased in the rhizosphere with the progression of the development and growth. The results showed that with the expansion of the root area of host plants, the occupation ratio of type A rhizobia including the serogroup USDA110 was high. Therefore, the Rj 2 Rj 3 Rj 4-genotypes were superior to other Rj-genotypes in terms of the inoculation effects of nodulation type A rhizobium, B. japonicum USDA110. However, the preference of the Rj 2 Rj 3 Rj 4-genotype for serogroup USDA110 is not sufficient to rule out the competition with the other serogroups in this study. Therefore, the study should be centered on the isolation of more efficient (Hup+) and highly compatible rhizobial strains with the Rj 2 Rj 3 Rj 4- genotypes.  相似文献   
78.
ABSTRACT

This study reports the relationship of the leaf ionic composition with the grain yield and yield components of wheat in response to salinity x sodicity and salinity alone. The study was conducted in soil culture in pots with three treatments including control (ECe 2.6 dS m? 1 and SAR 4.53), salinity (ECe 15 dS m? 1 and SAR 9.56), and salinity x sodicity (ECe 15 dS m? 1 and SAR 35). The soil was treated before being put in the pots and the pots were arranged in a completely randomized factorial arrangement with five replications. The seeds of three wheat genotypes were sown directly in the pots and the study was continued till the crop maturity. At booting stage, the leaf second to the flag leaf of each plant was collected and analyzed for sodium (Na+), potassium (K+), and chloride (Cl?). At maturity, plants were harvested and data regarding grain yield and yield components were recorded. This study shows that salinity and sodicity in combination decreases the grain yield of wheat more than the salinity alone with a greater difference in the sensitive genotype. This study also shows that as for salinity, the maintenance of lower Na+ and higher K+ concentrations and higher K+: Na+ ratio in the leaves relates positively with the better development of different yield components and higher grain yield in saline sodic soil conditions. Although, the leaf Cl? concentration was increased significantly by salinity as well as salinity x sodicity and would have affected the growth and yield, yet it does not seem to determine the genotypic tolerance or sensitivity to either salinity or salinity x sodicity.  相似文献   
79.
Application of zinc (Zn) [50, 100, 200, 300, and 400 μ g zinc sulfate (ZnSO4)/g of soil] reduced the foliage and the total growth of pigeon pea [Cajanus cajan (Linn.) Huth]. The root-shoot length ratio, varying little with age, was relatively low in the treated plants. Decrease in dry weights of stem and root was more pronounced in the late stages of plant development. The root-shoot dry weight ratio, maximum in the flowering stage, was lower in treated plants than in the control. Number of pods per plant declined, showing a positive correlation with Zn concentration. Net photosynthetic rate, declining with plant age, was significantly low in the treated plants. Density and size of stomata and trichomes, stomatal conductance, intercellular carbon dioxide concentration, quantity of green pigments, nitrate reductase activity, and the nitrate and protein contents in the leaves also declined significantly. Proportion of vascular tissues both in stems and roots increased with plant age with a concomitant reduction of pith and cortex. Under zinc stress, the relative proportion of tissues varied inconsistently. Dimensions of vessel elements and fibers in stems and roots, increasing with the plant age, were always smaller in the treated plants. The vulnerability factor and mesomorphic ratio of treated plants declined, suggesting induction of water stress due to zinc treatments. Accumulation of Zn2 + in different plant parts was considerably high at each developmental stage of the treated plants, and showed a positive correlation with Zn in the soil.  相似文献   
80.
The zinc (Zn) requirement of a maize (Zea mays L.) hybrid (‘FHY-396’) and an indigenous variety (‘EV-7004’) was measured at low (22.4 ± 5°C) and high (28.8 ± 5°C) root-zone temperatures (RZT). Four Zn rates (0, 3, 9 and 27 mg kg?1 soil) were applied to a calcareous loam soil in pots for the glasshouse study. Shoot and root dry matter yields were significantly more at the higher RZT. Regardless the RZT, maximum relative shoot dry matter yield in hybrid and variety was produced, respectively, at 9 and 3 mg Zn kg?1 soil. Zinc concentration in roots and shoots of both the cultivars increased with Zn rates and it was significantly more at the higher RZT. Cultivars differed in critical Zn concentration (CZnC) required for maximum shoot dry matter yield. The CZnC ranged from 25 to 39 μg Zn g?1 plant tissue for optimum growth of both the cultivars at low and high RZT.  相似文献   
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