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Use of poor-quality groundwater has become inevitable for irrigation to compensate rapidly increasing water demands in many arid and semiarid regions. Salinity and sodicity are the principal soil and water quality concerns in such areas. Many saline–sodic and sodic soils have saline or saline–sodic subsurface drainage waters. Amelioration of these soils needs a source of calcium (Ca2+) that can replace the excess exchangeable sodium (Na+). Most of these soils, however, contain calcite (CaCO3) of extremely low solubility. The native calcite does not supply adequate levels of Ca2+ for soil amelioration as do other chemical amendments. Phytoremediation may help ameliorate such soils through cultivation of certain crops tolerant to ambient soil salinity and sodicity. This amelioration strategy works through plant root action to help dissolve CaCO3 to supply adequate Ca2+ without the application of an amendment. During a 3-year field experiment conducted under irrigated conditions, we evaluated phytoremediation against soil application of gypsum and farm manure, and water treatment with sulphuric acid on a calcareous saline–sodic soil (pHs=8.0–8.4, ECe=24–32 dS m−1, SAR=57–78, CaCO3=45–50 g kg−1 for the top 0.15 m depth; Calcic Haplosalids). A saline–sodic water (EC=2.9–3.4 dS m−1, SAR=12.0–19.4, RSC=4.6–10.0 mmolc l−1, SARadj=15.6–18.4) was used to irrigate the rice (Oryza sativa L.) and wheat (Triticum aestivum L.) crops grown in rotation. Active desalinisation and desodication processes were observed in all the treatments. After the final wheat crop, the 1.2 m soil profile ECe was 7±0.5 dS m−1 and SAR was 15±2 with non-significant treatment differences, indicating comparable soil amelioration effect of phytoremediation with other treatments. Better crop yields were obtained from the manure-treated plots, owing to its annual addition to the soil that possibly improved soil fertility. Phytoremediation needed minimum capital input because no initial investment was made to purchase the amendments. 相似文献
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Expression profiling of transgenes (Cry1Ac and Cry2A) in cotton genotypes under different genetic backgrounds 
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下载免费PDF全文 Kashif NOOR Hafiza Masooma Naseer CHEEMA Asif Ali KHAN Rao Sohail Ahmad KHAN 《农业科学学报》2022,21(10):2818-2832
Transgenic cotton carrying the Cry1Ac gene has revolutionized insect pest control since its adoption, although the development of resistance in insect pests has reduced its efficacy. After 10 years of cultivating Bacillus thuringiensis (Bt) cotton with a single Cry1Ac gene, growers are on the verge of adopting Bt cotton that carries the double gene (Cry1Ac+Cry2A) due to its better effectiveness against insect pests. Thus, the current study was designed to evaluate the role of each gene in the effectiveness of Bt cotton carrying the double gene. The expression levels of the Cry1Ac and Cry2A genes were evaluated in the leaves of 10 genotypes (2 parents and 8 F1 hybrids) at 30 days after sowing (DAS), while samples of leaves, bolls and flowers were taken from the upper and lower canopies at 70 and 110 DAS. The F1 hybrids were developed through reciprocal crosses between two Bt (CKC-1, CKC-2) and two non-Bt (MNH-786, FH-942) parents. The differential expression of transgenes was evaluated through Enzyme Linked Immuno-Sorbent Assay (ELISA). The results showed that the MNH786×CKC-1 hybrid had the highest concentrations of Cry1Ac gene at 30 DAS (3.08 µg g–1) and 110 DAS (1.01 µg g–1) in leaves. In contrast, the CKC-2×MNH-786 hybrid showed the lowest concentrations of Cry1Ac gene at 30 DAS (2.30 µg g–1) and 110 DAS (0.86 µg g–1). The F1 hybrid FH-942×CKC-2 showed the highest concentrations of Cry2A gene at 30 DAS (8.39 µg g–1) and 110 DAS (7.74 µg g–1) in leaves, while the CKC-1×MNH-786 hybrid expressed the lowest concentrations of Cry2A gene at 30 DAS (7.10 µg g–1) and 110 DAS (8.31 µg g–1). A comparison between the two stages of plant growth showed that leaves had the highest concentrations at 30 DAS, whereas the lowest concentrations were observed at 110 DAS for both genes in leaves. When the expression pattern was compared between various plant parts in genotype CKC-2, it was found that leaves had higher concentrations of Cry1Ac (3.12 µg g–1) and Cry2A (8.31 µg g–1) at 70 DAS, followed by bolls (Cry1Ac (1.66 µg g–1) and Cry2A (8.15 µg g–1)) and flowers (Cry1Ac (1.07 µg g–1) and Cry2A (7.99 µg g–1)). The genotype CKC-2 had higher concentrations of Cry1Ac (3.12 µg g–1) and Cry2A (8.31 µg g–1) in the upper canopy but less accumulation (2.66 µg g–1 of Cry1Ac, 8.09 µg g–1 of Cry2A) in the lower canopy at 70 DAS. Similarly, at 110 DAS, the expression levels of Cry1Ac and Cry2A in upper and lower canopy leaves were 1.52 and 7.92 µg g–1, and 0.99 and 7.54 µg g–1, respectively. Hence, the current study demonstrates that different genotypes showed variable expression for both of the Cry1Ac and Cry2A genes during plant growth due to different genetic backgrounds. The Cry2A gene had three-fold higher expression than Cry1Ac with significant differences in expression in different plant parts. The findings of this study will be helpful for breeding insect-resistant double-gene genotypes with better gene expression levels of Cry1Ac and Cry2A for sustainable cotton production worldwide. 相似文献
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In order to ascertain physico-chemical, functional and geometrical traits of apricot fruit from Northern Areas of Pakistan, six predominantly grown varieties namely, Alman, Habi, Khakhas, Mirmalik, Neeli and Shai were selected in this study. Proximate composition as crude fat (2.1–3%), crude protein (6.18–8.7%), crude fiber (11.85–13.6%), ash (9.45–12.1%) and total sugars (56.8–64.9%) were determined on dry weight basis. The data showed variations among the investigated parameters in all varieties. Functional properties of apricot fruit viz. ascorbic acid (67.39–90.94 mg/100 g), total phenolic compounds (4590–7310 mgGAE/100 g), total carotenoids (10.09–18.13 mg/100 g β-carotene) and antioxidant activity (56.84–82.33%) were also recorded. The data pertaining to mineral contents (mg/100 g) revealed K as the predominant element (2040–3000) followed by P, Mg, Ca, Na and Fe among all the tested samples. Furthermore, geometrical characters of apricot varieties were also determined as important sensory and technological attributes on fresh weight basis. The result from the present study showed that all the tested varieties are highly nutritious and rich in functional components. 相似文献
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Kashif Akhtar Weiyu Wang Ahmad Khan Guangxin Ren Sajjad Zaheer Tanveer A. Sial Yongzhong Feng Gaihe Yang 《Soil Use and Management》2019,35(3):526-535
Field experiments were conducted to study soil properties, soil enzymes activities, water use efficiency (WUE) and crop productivity after six years of soya bean straw mulching in the semi‐arid conditions of China. The experiment included four treatments: CK (Control), N (240 kg N ha‐1), H (soya bean straw mulching at half rate 700 kg ha‐1 with 240 kg N ha‐1) and F (soya bean straw mulching at full rate 1,400 kg ha‐1 with 240 kg N ha‐1). Soil organic carbon (SOC), soil labile organic carbon (LOC), soil available N (AN), available P (AP) and enzyme activities were analysed after wheat harvesting in 2016 and 2017. Results show that straw amounts had positive effects on the soil fertility indices being higher for treatment F. The SOC, LOC, AN, AP and enzyme activities (i.e. saccharase, urease and alkaline phosphatase) were in the order of F > H > N > CK. High wheat grain yield and WUE were observed for F treatment. A total of six years mulching along with 240 kg ha‐1 nitrogen fertilizer application is sufficient for wheat yield stability and improving soil properties except urease activities in the semi‐arid condition of China. However, the straw mulching amount should be further studied with minimum nitrogen fertilizer for an environment‐friendly and effective approach for improving the soil biological properties with adequate crop production on a sustainable basis in the semi‐arid region of China. 相似文献
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本研究的目的是确定豌豆F1和F2代的6个相对性状的遗传和连锁关系,并在F3代中选择高产抗白粉病株系.选择两个近等基因系Falloner和11760-3ER进行杂交,得到的F2代的性状分离比均为3:1,这符合X2(p＞0.07)适合度检测,表明是单基因遗传.花色和种子颜色与花青素关联的似然比分别为44.31和34.91,每个叶片中小叶数目和卷须类型关联的似然比为33.21.这三个关联的质量性状在P＜0.00具有非常显著的相关性,但与白粉病性状均不相关联.选择F3代的4个与产量密切相关的数量性状进行研究,发现总荚重和种荚比分别具有49.77%和20.01%的最高变异系数.相关性研究发现,总荚重与籽粒重量、荚宽、荚长和种荚比呈显著正相关.荚长与种荚比呈显著正相关.根据数量性状值和白粉病抗性表现,选择GN070140-2,GN070143-1和GN070140-0三个株系作为以后的栽培品种. 相似文献
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Moon-Young Kim Jae-Jun Ahn Kashif Akram Gui-Ran Kim Mi-Seon Jeong Ji-Young Kwak 《Journal Of Aquatic Food Product Technology》2013,22(3):299-306
ABSTRACTRadiation-specific luminescence properties in irradiated dried-fishery products (pollack, little pollack, clams, and shrimp) were investigated at different dose levels (0–10 kGy). Photostimulated luminescence (PSL) analysis of whole samples was effective for dried clams and shrimp, while low PSL sensitivity was observed in dried pollack and little pollack. Thermoluminescence (TL) analysis was conducted after isolation of silicate minerals, in which the two methods of mineral isolation—density separation and acid hydrolysis—were compared. Irradiated samples were easily distinguishable through the strong TL glow curves, with maximum peaks in temperature range of 150–250°C. TL ratios (TL1/TL2) were < 0.1 for nonirradiated samples, while > 0.1 for irradiated. There was a clear effect of applied irradiation dose, with a negligible effect of the method used for mineral separation. The mineral composition showed that feldspar and quartz minerals were mainly responsible for the well-characterized luminescence behavior upon irradiation. 相似文献
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Sahena Ferdosh Nik Norulaini Nik Ab Rahman Md. Jahurul Haque Akanda Kashif Ghafoor Mohd. Omar Ab Kadir 《Journal Of Aquatic Food Product Technology》2013,22(2):230-239
ABSTRACTFish oil was extracted and simultaneously collected into six fractions based on molecular weight and the chain length of triglycerides in terms of fatty acid constituents without splitting of the triglycerides, using supercritical carbon dioxide (SC-CO2) at optimized conditions of 40 MPa, 65°C, and a flow rate 3 mL min?1. In each type of fractionation, the first fraction (F1) was rich in saturated fatty acids (SFA; 52.57 to 61.26%), followed by monounsaturated fatty acids (MUFA; 22.17 to 23.22%) and polyunsaturated fatty acids (PUFA; (0.54 to 20.37%); the sixth fraction (F6) was rich in PUFA (48.93%), followed by MUFA (33.59%) and SFA (13.61%). It was obvious that short-chain fatty acids were extracted at an earlier fraction; therefore, the latter fractions were dominant in long-chain fatty acids, especially MUFA and PUFA. Thus, omega-3 fish oil (last three fractions) was successfully separated to be used as a value-added health product. 相似文献
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The prolonged irrigation with marginal quality water can cause secondary salinization of soils, which necessitates for better understanding of water management alternatives. Relative performance of sulfuric acid and gypsum is still controversial to counter sodium hazards in soil/water system. As an alternative, sulfurous acid generators (SAG) are also being marketed. But up-till-now, there is not even a single field study published in scientific journals about their efficiency and economical viability for the treatment of saline-sodic water. Therefore, a field study was carried out to compare the effectiveness of SAG and alternate amendments applied on an equivalent basis to grow rice crop. SAG treatment of saline-sodic tube well water decreased only residual sodium carbonate (RSC) from 5.4 to 3.6 mmolc l−1, and had no beneficial effect on its sodium adsorption ratio (SAR) or electrical conductivity (EC). All the treatments kept soil EC and SAR around their respective threshold levels. For paddy yield, SAG, sulfuric acid, and gypsum treatments depicted nonsignificant differences. SAG and sulfuric acid treatments of water were about six times expensive than that of gypsum. It was concluded that soil-applied gypsum, to counter sodic hazards of irrigation water, is economical to sustain irrigated rice in dry regions. 相似文献
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Hussain Kashif Yingxing Zhang Anley Workie Riaz Aamir Abbas Adil Hasanuzzaman Rani Md. Hong Wang Xihong Shen Liyong Cao Shihua Cheng 《水稻科学》2020,27(3):246-254
Grain size is one of the critical agronomic traits governing grain yield and quality in rice. However, the underlying genetic mechanisms that control grain size in rice are poorly understood. We used an introgression line derived from Zhonghui 8015 and Oryza rufipogon Griff. This introgression line was evaluated under two different environmental conditions to dissect the quantitative trait loci controlling grain size. Genome-wide association study (GWAS) was performed using 28 193 SNPs through a general linear model, and 56 significant SNPs on different loci associated with the 4 grain size traits were detected. Cloned genes including GS3 and qGL3 showed substantial effects on grain length and size. Seven new stable loci were identified with pleiotropic effects on grain size. Haplotype, gene expression analyses, combined gene-based associations, and functional annotations permitted the shortlisting of important dominant genes including GS3 and qGL3. 相似文献