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11.
Physical characteristics, amino acids composition, protein profiling, pasting characteristics, and phenolic compounds of brown rice (BR) and germinated brown rice (GBR) from different paddy cultivars (PB1, PS44, PB1509, PB1121, and PS5) were investigated. L* (lightness) decreased, but a* (redness and greenness) and b* (yellowness and blueness) increased with germination. Protein and ash content increased, whereas fat and amylose contents decreased with germination. GBR showed lower hardness and gumminess than BR. Foam stability and water absorption capacity from GBR flour were higher compared with BR flour. Accumulation of γ‐aminobutyric acid, histidine, arginine, proline, methionine, and acidic amino acids increased significantly with germination, and increase was related to change in accumulation of glutelin and prolamins. The accumulation of prolamins and glutelin acidic and basic subunits decreased with germination. GBR flour showed lower pasting viscosities compared with BR flour. Ferulic acid, p‐coumaric acid, and quercetin were present in both fractions of the bound form. GBR showed improved nutritional quality that varied in different cultivars. PB1121 was observed to be the best for producing GBR owing to greater changes brought in protein content, essential amino acids, catechin, chlorogenic acid, protocatechuic acid, vanillic acid, and foam stability.  相似文献   
12.
Yao  Yihan  Cao  Shanzhi  Gong  Xueliu  Singh  Bhupinder Pal  Fang  Yunying  Ge  Tida  Wang  Hailong  Li  Yongfu 《Journal of Soils and Sediments》2022,22(10):2640-2653
Purpose

Intensive long-term management practices in forest ecosystems can markedly influence soils’ physicochemical and microbial properties. However, their effects on the magnitude of nutrient pools and activities of enzymes regarding nutrient cycling in subtropical forest soils remain unclear. This study aimed to examine effects of long-term intensive management (organic mulching and chemical fertilization) on concentrations of different C, N, and P fractions and activities of enzymes involved with nutrient cycling in a subtropical Lei bamboo (Phyllostachys violascens) forest soil.

Materials and methods

Soil samples were taken from a chronosequence of Lei bamboo forests with intensive management spanning 0, 5, 10, and 15 years. Concentrations of various forms of C, N, and P, as well as activities of β-glucosidase, cellobiohydrolase, urease, protease, and acid phosphatase were measured.

Results and discussion

The results revealed that the concentrations of different classes of C (water-soluble organic C, hot-water-soluble organic C, and readily oxidizable C), N (NH4+-N, NO3?-N, and water-soluble organic N), and P [resin-inorganic P (Pi), NaHCO3-Pi, NaHCO3-organic P (Po), NaOH-Pi, NaOH-Po, HCl-Pi, and residual-P] were enhanced markedly with prolonged duration of intensive management. Furthermore, activities of β-glucosidase, cellobiohydrolase, urease, protease, and acid phosphatase were increased following a 5-year treatment, while they were markedly reduced from 5- to the 15-year treatments. The 15 years of intensive management significantly reduced microbial biomass C and N concentrations by 8.2% and 31.9%, respectively, compared to the control.

Conclusions

We concluded that long-term intensive management led to the accumulation of C, N, and P, while it negatively impacted microbial biomass and activities of enzymes involved in nutrient cycling in subtropical Lei bamboo forest soils. Consequently, a reduction in chemical fertilizers should be considered toward the long-term sustainable development of subtropical Lei bamboo forests.

  相似文献   
13.
Maintenance of tropical soil quality for crop production without damaging the environment is a challenge and thus the development of an efficient nutrient-management technique is important. Soil amendment by organic manures has been widely accepted as an efficient nutrient-management technique in tropical agriculture. In this study, a long-term laboratory experiment was conducted to investigate the influence of organic manures of different sources (e.g. cattle manure, poultry manure, vermicompost and oil cakes) on changes in pH, electrical conductivity, organic C and nutrient content (mineral N, available phosphorous and potassium) in tropical alluvial soil. Applications of organic amendments in this study indicated considerable changes in the basic soil physico-chemical properties and different nutrient levels. Soil pH declined slightly, whereas organic C and all the other nutrients increased distinctly, due to the application of organic manures. Thus, the magnitude of changes in the soil properties was dependent on the nature of the organic manure.  相似文献   
14.
Field experiments were conducted during the wet seasons of 1991,1992 and 1993 at the Abubakar Tafawa Balewa University Farm, Bauchi (10 ° 22'N, 09 ° 47'E) to study the response of sunflower ( Helianthus annaus L.) to N rates and plant population under rainfed conditions. Four N rates (0, 50, 100 and 150 kg N ha -1) and four plant populations (40000,80000,120000 and 160000 plants ha-1) were factorially combined in a randomized complete block design with three replications. Leaf area index, shoot dry weight and seed yield (kg ha-1) increased significantly with increasing N rates from 0 to 100 kg N ha-1. The growth and yield parameters per plant decreased significantly with increasing plant populations from 40000 to 160000 plants ha-1, but the seed yield (kg ha-1) obtained at 80000 plants ha-1 was significantly higher than all the other plant populations. The interactions of N x plant population confounded the main effect of each factor on the growth and yield of sunflower. The seed yield (3425 kg ha-1) obtained from the use of 100 kg N ha-1 at 80000 plants ha-1 was significantly higher than those obtained from all other combinations of N x population and out-yielded the main effects of 100 kg N ha-1 and 80000 plants ha-1 by 18 % and 25 %, respectively. The use of 100 kg N ha-1 at 80000 plants ha-1 is therefore recommended for maximum yield of sunflower in Bauchi.  相似文献   
15.
Summary Reciprocal recurrent selection was carried out with two populations of maize (Zea mays L.) having good combining ability. We selected for higher grain yield, early maturity, shorter plant height and lodging resistance. Two cycles were completed in two years (four seasons), by resorting to late planting of S1 lines for recombination in the main season in which top-cross families were assessed. Top-crosses and selfings were made in the off-season. The original and improved versions of the populations and their crosses were evaluated in multilocation trials. The superiority of the population hybrid was 10.3% for grain yield, 5.5% for plant height and 1.8 days to silk. The improved hybrid had delayed leaf senescence and better resistance to lodging and post-flowering stalk rots. Among the yield components, only ear girth showed improvement. Syn 2 of the improved population cross showed a yield reduction of 6.2% in comparison to Syn 1. Intrapopulation gains were not significant except for lodging resistance in one population.  相似文献   
16.
17.
Exchange behaviour of potassium versus magnesium was studied on surface soil samples of 3 Ustochrepts from a semiarid tropical region in relation to different levels of cattle farmyard manure (FYM, 0, 2.5, 5 and 10%). Magnesium saturated soil samples were equilibrated with KCl + MgCl2 solutions having a range of equivalent ion fraction of K from 0 to 1 in the equilibrium solutions. The experimental results were analysed and interpreted, using different exchange selectivity quotients and thermodynamic parameters. Application of FYM caused a small but consistent increase in the K-preference over Mg as depicted from the normalized exchange isotherms. Standard free energy of K-Mg exchange were strongly negative (ΔGo-6.97 to ?9.47 kJ eq?1 by Gaines and Thomas approach; ΔG'o ?10.85 to ?14.15 kJ M?1 by Babcock and Duckart approach), suggesting a strong thermodynamic preference for K over Mg in these soils. For comparable treatments, ΔGo were about ?0.84 to ?1.25 kJ eq?1 more negative for K-Mg, compared to K-Ca system reported earlier. ΔGo for 10% FYM treatments became more negative over the controls by 2.34, 1.40 and 0.53 kJ eq?1 for Hissar, Panipat and Pehowa soils, respectively. All the selectivity quotients scrutinized in this investigation, viz., Gapon (KG), Vanselow (Kv) and thermodynamic (KN) were strongly K-saturation dependent; the dependence becoming more pronounced with the addition of FYM.  相似文献   
18.
ABSTRACT

Delayed sowing and imprecise application of irrigation water to cotton has been the major hurdle in sustaining cotton yield in north-western India. Therefore, studies were initiated to ascertain the impact of heavy or normal level of presowing irrigation (PSI), scheduling time of first postsowing irrigation (POSI) under two sowing dates (SDs) on cotton arranged in a split block design replicated thrice. PSIh (100 mm) recorded 23.2% higher seed cotton yield over PSIn (70 mm) owing to better yield attributes and higher stand. First POSI at 4 weeks after sowing (WAS) resulted the highest yield (3072 kg ha?1), while one at 6 WAS (POSI6) recorded least due to poor population and reduced yield attributes. Water productivity under POSI6 was lesser by 29.1%, 25.2%, and 16.2% as compared to POSI3, POSI4, and POSI5, respectively. April sown crop out yielded the May sown cotton crop by 939 kg ha?1 due to better yield attributes. Nitrogen factor productivity (NFP) among SD remained higher by 23.3% for April as compared to May sowing. PSIh exhibited better NFP over PSIn. POSI6 recorded least NFP by 24.4%, 28.5%, and 16.3% as compared to POSI3, POSI4, and POSI5, respectively and was indicative of relatively poor utilization of N under delayed schedules. Therefore, planting in April after heavy PSI and scheduling first POSI at 4 WAS is best strategy for sustaining cotton yield and maximizing farmer profitability.  相似文献   
19.
In the present study, allele mining was conducted on a panel of drought related candidate genes in a set of 96 barley genotypes using EcoTILLING, which is a variant of the targeting induced local lesions in genomes (TILLING) technology. Analyzing approximately 1.5 million basepairs in barley a total number of 94 verified unique haplotypes were identified in 18 amplicons designed for 9 genes. Overall, 185 single nucleotide polymorphisms (SNPs) and 46 insertions/deletions (INDELs) were detected with a mean of 1SNP/92 bp and 1INDEL/372 bp genomic sequence. Based on overlapping haplotype sequences, markers were developed for four candidate genes (HvARH1, HvSRG6, HvDRF1, HVA1), which allows distinguishing between the main haplotypes showing either differences in amino acid sequence or which have larger INDELs in the promoter region. As “proof of concept”, the HvARH1 and HvSRG6 haplotypes were tested for the level of abscisic acid-induced gene expression in subsets of genotypes belonging to different haplotype categories. An integrated database was developed to contain information about the genes, genotypes, and haplotypes analyzed in this study. The database supplies profound information about the natural variation in the tested drought related candidate genes providing a significant asset for further mapping studies dealing with this highly polygenic trait.  相似文献   
20.
An organic material composed of neutral free radicals based on the spirobiphenalenyl system exhibits a room temperature conductivity of 0.3 siemens per centimeter and a high-symmetry crystal structure. It displays the temperature-independent Pauli paramagnetism characteristic of a metal with a magnetic susceptibility that implies a density of states at the Fermi level of 15.5 states per electron volt per mole. Extended Hückel calculations indicate that the solid is a three-dimensional organic metal with a band width of approximately 0.5 electron volts. However, the compound shows activated conductivity (activation energy, 0.054 electron volts) and an optical energy gap of 0.34 electron volts. We argue that these apparently contradictory properties are best resolved in terms of the resonating valence-bond ground state originally suggested by Pauling, but with the modifications introduced by Anderson.  相似文献   
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