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111.
Manganese (Mn) deficiency is prevalent in rice-growing regions resulting in poor paddy yield and human health. In this study, role of Mn, applied through various methods, in improving the productivity and grain biofortification of fine grain aromatic rice was evaluated. Manganese was delivered as soil application (SA) (0.5 kg ha?1), foliar spray (FA) (0.02 M Mn), seed priming (SP) (0.1 M Mn) and seed coating (SC) (2 g Mn kg?1 seed) in conventional (puddled transplanted flooded rice) and conservation (direct seeded aerobic rice) production systems at two different sites (Faisalabad, Sheikhupura) in Punjab, Pakistan. Manganese application, through either method, improved the grain yield and grain Mn contents of fine grain aromatic rice grown in both production systems at both sites. However, Mn application as SC and FA was the most beneficial and cost effective in improving the productivity and grain biofortification in this regard. Overall, order of improvement in grain yield was SC (3.85 t ha?1) > FA (3.72 t ha?1) > SP (3.61 t ha?1) > SA (3.36 t ha?1). Maximum net benefits and benefit–cost ratio were obtained through Mn SC in flooded field at Faisalabad, which was followed by Mn SP in direct seeded aerobic rice at the same site. However, maximum marginal rate of return was noted with Mn SC in direct seeded aerobic rice at both sites. In crux, Mn nutrition improved the productivity and grain biofortification of fine grain aromatic rice grown in both conventional and conservation production systems. However, Mn application as seed treatment (SC or SP) was the most cost effective and economical.  相似文献   
112.
Reduced early crop growth and limited branching are amongst yield limiting factors of linola. Field response of seed priming treatments viz. 50 mmol L−1 salicylic acid (SA), 2.2% CaCl2 and 3.3% moringa leaf extract (MLE) including untreated dry and hydropriming controls was evaluated on early crop growth and yield performance of linola. Osmopriming with CaCl2 reduced emergence time and produced the highest seedling fresh and dry weights including Chl. a contents. Osmopriming with CaCl2 reduced crop branching and flowering and maturity times and had the maximum plant height, number of branches, tillers, pods and seeds per pod followed by MLE. Increase in seed weight, biological and seed yields was 9.30, 34.16 and 39.49%, harvest index (4.12%) and oil contents (13.39%) for CaCl2 osmopriming. Positive relationship between emergence and seedling vigor traits, 100-seed weight, seed yield with maturity time, 100-seed weight and seed yield were found. The study concludes that seed osmopriming with CaCl2 or MLE can play significant role to improve early crop growth and seed yields of linola.  相似文献   
113.
Fifty-five mungbean lines were evaluated for days to maturity and grain yield per plant. This material showed considerable range of variability for the target traits. Eight genetically diverse parents were selected and used for a full diallel set of crosses to study the mode of inheritance for earliness related parameters (days to flowering, days to maturity and length of reproductive phase) during summer 2005. The F1 generation of these crosses was sown during the spring of 2006 and the selfed seeds were used to raise the F2 generation during kharif season. The data recorded from two generations were subjected to genetic analysis. The formal ANOVA showed the significance of both additive and dominance effects for all the traits in both generations. Significance of D, H1 and H2 components also confirmed the contribution of both additive and dominance effects in controlling the inheritance of these traits. The estimates of narrow sense heritability were low to moderate except higher estimates for days to maturity in F2 generation, while the broad sense heritability estimates were relatively higher. Seasonal and environmental effects were also found to be significant. In view of the complex nature of gene action for earliness, it is suggested that breeders should look for transgressive recombinants of earliness and other desirable attributes in later segregating generations to gain higher genetic advance. The variety NM92 was found to be the best source of earliness in mungbean breeding.  相似文献   
114.
Seed dormancy and pre-harvest sprouting are important traits in bread wheat. Bi-parental populations have permitted the identification of several genes/quantitative trait loci controlling these traits, mapping to various bread wheat chromosomes. Here, we report the use of association mapping to uncover the genetic basis of both traits in a panel of 96 diverse winter wheat cultivars to establish the presence of marker-trait associations on many chromosomes. Potential candidate genes were identified by studying the gene content of the chromosome bins into which the major marker trait associations mapped.  相似文献   
115.
Xieyou9308 is the first commercial super hybrid rice released in 1996 in China. To clarify its genetic mechanism underlying high yield potential, a recombinant inbred line (RIL) population derived from the cross between the maintainer line XieqingzaoB (XQZB) and the restorer line Zhonghui9308 (ZH9308) and two derived backcross F1 (BCF1) populations were developed for the identification of quantitative trait loci (QTLs) related to ten important agronomic traits (tiller number (TN), heading date (HD), and grain yield per plant (GYPP), etc.). The BCF1 performance was closely correlated with the performance of their parental RILs according to both the analysis of broad-sense heritability (h B 2) and phenotypic correlation coefficient (PCC) in the two BCF1 populations, but not proved by QTL analysis. A total of 21 additive-effect main QTLs (M-QTLs), 22 dominant-effect M-QTLs, and 19 dominant-effect M-QTLs were detected with the WinQTLCart 2.50 software for the ten traits in the RIL and two BCF1 populations, respectively. Of theses, three QTLs (qHD7a, qPPP3a, and qPL10) of 21 were detected repeatedly in the RIL and one BCF1 populations, ten QTLs underlying four traits were only detected repeatedly in two BCF1 populations, and nine QTLs controlling more than two traits were detected repeatedly, the additive-effect QTLs and dominant-effect QTLs play an important role in the performance of agronomic traits and no epistatic QTL of additive by additive effect and dominant by dominant-effect was detected for all traits in three populations. This research is valuable for M-QTL related to important agronomic trait in future fine mapping and positional cloning.  相似文献   
116.
Distal ulnar ostectomy may be performed palliatively in patients with distal ulnar osteosarcoma. Concurrent arthrodesis of the carpus has been proposed to counteract joint instability following transection of carpal ligaments associated with removal of the distal ulna. The objective of this prospective one group pretest, posttest study was to assess stability of the carpus following distal ulnar ostectomy using pre‐ and postoperative stress radiographic views in a group of canine cadaver limbs. Seven thoracic limbs from six canine cadavers weighing more than 20 kg were obtained. Lateral and dorsopalmar, extended lateral, medial stress, and lateral stress radiographs were made before and after distal ulnar ostectomy. Presurgical canine cadaver carpal angle measurements were as follows (mean ± standard deviation): extension 205.9° ± 5.4; medial stress 25.1° ± 5.7; and lateral stress 13.3° ± 5.2°. Cadaver limb joint angles exceeded those previously reported in live dogs. A significant increase in carpal angle was noted following ulnar ostectomy. The mean increases in carpal angle were as follows: (mean ± standard deviation (95% confidence interval)): extension 6.2° ± 4.9 (2.6–9.8) (P = 0.007); medial stress 3.2° ± 3.0 (1.0–5.5) (P = 0.015); lateral stress 6.2° ± 5.2 (2.4–10.1) (P = 0.010). Findings from this cadaver study support the use of supplementary stabilization for clinical patients undergoing distal ulnar ostectomy. Future studies are needed in clinical patients to evaluate changes in limb positioning and gait associated with distal ulnar ostectomy.  相似文献   
117.
A filter-paper bioassay method was used to investigate the differential response of 23 barley (Hordeum vulgare L.) genotypes to boron (B) toxicity. Two-day-old seedlings with equal radicles were treated with 10 (B10) or 100 (B100) ppm B for 10 d. Root and shoot growth was not affected by B10, but root growth was significantly reduced by B100. The shoot growth at B100 was either unaffected or affected to a smaller extent than the root. A significant inverse correlation was found between B content of seed and seed germination, and between root growth and B contents of root and shoot under B100. The barley genotypes with lower B contents in seeds had a higher germination, longer root length, and accumulated less B in roots and shoots when treated with B100. The B-tolerant genotypes with longer roots had lower B contents in their seed, root, and shoot and vice versa. These results suggest that a great variation exists among barley genotypes in response to high B application. There was no difference between naked (uncovered) and covered varieties in response to B100. The B tolerance could be attributed to the lower B content of seed and lower uptake or accumulation of B in the root and shoot.  相似文献   
118.
Impact of tannic acid (TA), date seed extract (DSE), catechin (CT) and green tea extract (GTE) on lipid oxidation, microbial load and textural properties of camel meat sausages during 12 days of refrigerated storage was investigated. TA and CT showed higher activities in all antioxidative assays compared to DSE and GTE. Lipid oxidation and microbial growth was higher for control sausages when compared to other samples. TA and CT at a level of 200 mg/kg were more effective in retarding lipid oxidation and lowering microbial count (P < 0.05). Sausages treated with TA and DSE were found to have higher hardness, gumminess and chewiness values compared to other treatments (P < 0.05). Addition of different phenolic compounds or extract did not influence the sensory color of sausages. Furthermore, sensory quality was also found to be superior in TA and CT treated sausages. Therefore, pure phenolic compounds (TA and CT) proved to be more effective in retaining microbial and sensorial qualities of camel meat sausages compared to phenolic extracts (GTE and DSE) over 12 days of storage at 4°C.  相似文献   
119.
Containerized Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) seedlings were subjected to six moisture-stress treatments (ranging from 7 to 65% soil water content by volume) for 12 weeks. At the end of this period, there were significant differences in phenological, physiological, and morphological responses among the seedlings in the various moisture-stress treatments. In general, seedlings grown under very high or very low soil moisture conditions were adversely affected, while those grown under moderate conditions (29 to 53% soil water content) exhibited optimum growth, bud development, and nutrient and starch reserves. The use of vector analysis was found to be helpful in data interpretation. The results indicate the importance of closely monitoring nursery moisture regimes in order to achieve the best seedling quality.  相似文献   
120.
The potential of encapsulated calcium carbide (ECC) in improving growth, yield and physiology of cotton under salinity was evaluated in pot experiment. Salinity was induced by sodium chloride (NaCl) at 0, 1250 and 2000 ppm. The ECC was applied at the rate of 0, 15, and 30 mg kg?1 soil. The results revealed that ECC improved number of branches, yield, shoot dry biomass, root dry biomass, by 57, 67, 40, 22, and 18% respectively, over control. Similarly, net photosynthesis, stomatal conductance nitrogen, phosphorus and potassium (N, P and K) concentration of shoot were enhanced by 38, 34, 7, 25 and 11% over control, respectively. The induction of new set of proteins ranging from 11 to 26 kDa was also observed at various levels of ECC and salinity stress. These results proved the efficacy of very lower concentrations of ethylene produced by ECC and showed the behavior of different parameters of cotton to it under saline stress.  相似文献   
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