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41.
《Land Degradation u0026amp; Development》2017,28(5):1696-1703
An 8‐month greenhouse experiment with ryegrass (Lolium perenne L.) examined the relationship between the dynamics of potassium (K) reserves in soil and changes in clay minerals, using X‐ray diffraction. The capacity of soil to release K was consistent with its ability to supply it and was the highest in the soil samples collected from Laiyang (H1T2a), Harbin (H1T1) and Beibei (H2T4), followed by the sample from Jiangyan (H1T2b), and the lowest in the samples from Gao'an (H2T3a) and Wangcheng (H2T3b). Removal of soil K decreases the intensity of reflections for illite and increases that for interstratified clay minerals. The centre of gravity values of the clay fractions was significantly negatively correlated to the depletion of soil K reserves, as ascertained through chemical extraction or through plant action. The quantitative regression equations between the centre of gravity values and the dynamics of soil reserves of K can be used for predicting the release and plant availability of K even without growing a crop. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
42.
J. He Y.‐L. Du T. Wang N. C. Turner Y. Xi F.‐M. Li 《Journal of Agronomy and Crop Science》2016,202(5):372-383
Two old (Huangsedadou and Longxixiaohuangpi (LX)) and two new (Jindou 19 (JD) and Zhonghuang 30 (ZH)) soya bean (Glycine max (L.) Merr.) cultivars were used to investigate the influence of soil drying on the abscisic acid (ABA) accumulation in leaves, stomatal conductance (gs), leaf water relations, osmotic adjustment (OA), leaf desiccation tolerance, yield and yield components. The greater ABA accumulation was induced by soil drying, which also inducing gs decreased at higher soil water contents (SWC) and leaf relative water content (RWC) significantly decreased at lower SWC in the new soya bean cultivars than in the old soya bean cultivars. The soil water threshold between the value at which stomata began to close and the RWC began to decrease was significantly broader in the new cultivars than in the old cultivars. The new cultivars had significantly higher OA and lower lethal leaf water potential than old cultivars when the soil dried. The old cultivars had greater biomass, but lower grain yield than the new cultivars in well‐watered, moderate stress and severe stress conditions. Thus with soil drying, the new soya bean cultivars demonstrated greater adaptation to drought by inducing greater ABA accumulation, stomatal closure at higher SWC, enhanced OA and better water relations, associated with increased leaf desiccation tolerance, greater water use efficiency and higher yield. 相似文献
43.
P. Banterng G. Hoogenboom A. Patanothai P. Singh S. P. Wani P. Pathak S. Tongpoonpol S. Atichart P. Srihaban S. Buranaviriyakul A. Jintrawet T. C. Nguyen 《Journal of Agronomy and Crop Science》2010,196(3):231-242
The determination of optimum crop management practices for increasing soybean production can provide valuable information for strategic planning in the tropics. However, this process is time consuming and expensive. The use of a dynamic crop simulation model can be an alternative option to help estimate yield levels under various growing conditions. The objectives of this study were to evaluate the performance of the Cropping System Model (CSM)‐CROPGRO‐Soybean and to determine optimum management practices for soybean for growing conditions in the Phu Pha Man district, Thailand. Data from two soybean experiments that were conducted in 1991 at Chiang Mai University and in 2003 at Khon Kaen University were used to determine the cultivar coefficients for the cultivars CM 60 and SJ 5. The CSM‐CROPGRO‐Soybean model was evaluated with data from two experiments that were conducted at Chiang Mai University. The observed data sets from farmers’ fields located in the Phu Pha Man district were also used for model evaluation. Simulations for different management scenarios were conducted with soil property information for seven different soil series and historical weather data for the period 1972–2003 to predict the optimum crop management practices for soybean production in the Phu Pha Man district. The results of this study indicated that the cultivar coefficients of the two soybean cultivars resulted in simulated growth and development parameters that were in good agreement with almost all observed parameters. Model evaluation showed a good agreement between simulated and observed data for phenology and growth of soybean, and demonstrated the potential of the CSM‐CROPGRO‐Soybean model to simulate growth and yield for local environments, including farmers’ fields, in Thailand. The CSM‐CROPGRO‐Soybean simulations indicated that the optimum planting dates from June 15 to July 15 produced maximum soybean yield in a rainfed environment. However, the planting date December 15 produced the highest yield under quality irrigation. Soybean yield was slightly improved by applying nitrogen at a rate of 30 kg N ha?1 at planting. Soybean yield also improved when the plant density was increased from 20 to 40 plants m?2. The results from this study suggest that the CSM‐CROPGRO‐Soybean model can be a valuable tool in assisting with determining optimum management practices for soybean cropping systems in the Phu Pha Man district and might be applicable to other agricultural production areas in Thailand and southeast Asia. 相似文献
44.
I. Verinumbe 《Agroforestry Systems》1993,21(3):287-292
In order to obtain data which will facilitate the scientific development of multiple intercropping of trees in agroforestry systems, the effects ofFaidherbia albida Del. orZiziphus spina-christi L. Desf. on soil quality and on yield of interplantedLeucaena leucocephala L. were investigated. The distance to which bothFaidherbia albida andZiziphus spinachristi trees improved soil quality as well asLeucaena leucocephala andSorghum vulgare L. production around them was about two times the radius of the tree crown. Higher yields of plants underZiziphus spina-christi thanFaidherbia albida were explained by similarly higher concentrations of available phosphorus (P). Other soil parameters, including total nitrogen (N), were similar under both species; being higher under the tree canopies than away from them. The study identified optimum tree spacing for agroforestry to be twice the tree crown radius. It also demonstrated the advantages of multiple tree mixtures over pure stands in improving soil quality and productivity. 相似文献
45.
Rajanna G. Adireddy;Suman Manna;Neeraj Patanjali;Anupama Singh;Anchal Dass;Dibakar Mahanta;Vinod Kumar Singh; 《Journal of Agronomy and Crop Science》2024,210(4):e12730
The sustainability of global agriculture at higher productivity level is a concern owing to climate change, serious environmental footprints, dipping factor productivity and shrinking availability of natural resources, especially. The situation is worsening in the ‘Food Bowl of India’—Indo-Gangetic plains (IGP) by several amalgamated factors, such as declining groundwater, unpredictable precipitation owing to climate change and cultivation of heavy water duty crops. To neutralise these issues, a field experiment was executed for the period 2019–2021 to assess the efficacy of indigenous hydrogels (P-hydrogel and Superabsorbent polymer hydrogel-1118) and their application methods viz., seed treatment, slurry application and soil application on crop yield and water productivity, soil moisture dynamics and profitability in a soybean–wheat cropping system under irrigation and rainfed conditions. In both study years (2019–2020 and 2020–2021), due to higher seed germination percentage, irrigation application together with seed treatment and slurry application of superabsorbent polymer hydrogel-1118 improved system productivity by 8.1%–26.7% and system water productivity by 17.6%–33.8% over control. Wheat grain yield was enhanced by 8.0% (2019–2020) to 32.2% (2020–2021) due to superabsorbent polymer hydrogel-1118 hydrogel with 10 cm lesser use of irrigation water compared with control (no-hydrogel). Soil moisture content in 0–15 cm soil layer was also found higher by 1.8%–2.4% in superabsorbent polymer hydrogel-1118 and P-hydrogel slurry-applied plots. Therefore, higher gross profitability (31.8%), net profitability (89.8%) and B:C (26.9%) in wheat could be attributed to increased crop yields when seeds were treated with superabsorbent polymer hydrogel-1118. Therefore, the utilisation of modified hydrogel application, in the form of seed treatment (seed coating) and slurry application has demonstrated improvement in seed germination, crop yield and water productivity and made soybean–wheat cultivation more economical. This approach presents a feasible solution to achieving a viable production system of soybean and wheat crops by reducing irrigation amounts in the IGP of India, as well as other comparable ecological places worldwide. 相似文献
46.
Na Li Xingxia Ma Hongwei Xu Yongzhong Feng Guangxin Ren Gaihe Yang Xinhui Han Xiaojiao Wang Chengjie Ren 《Soil Use and Management》2020,36(4):751-765
Biochar has been shown to be potentially beneficial for enhancing yields and soil properties, and diminishing nitrogen (N) losses. However, it remains unclear how biochar regulates soil carbon (C) and N to mitigate N losses induced by straw mixing with N fertilizer in dryland soils. Therefore, we investigated the effects of straw mixing (S1), S1 with biochar (SB) and no straw inputs (S0), and routine urea application rates (N1) and 70% of routine rates (N0.7) on yields and N losses, and identify the relationship between N losses and soil C and N compounds. Results showed that N0.7 and N1 were suitable for the maize and wheat seasons, respectively, contributing to mitigating N losses without reducing crop yields. Moreover, in the maize season, N0.7-SB significantly mitigated the straw-induced NH3-N and N2O-N emissions by 106% and 81%, respectively. In the wheat season, N1-SB reduced the straw-induced NH3-N and N2O-N emissions by 35% and 66%, respectively. In addition, N0.7-SB sharply reduced soil inorganic N (SIN) storage in the maize season. Furthermore, the NH3-N and N2O-N emission rates were negatively correlated with dissolved organic carbon/SIN content (0–20 cm) (DOC/SIN0-20). N losses (N2O-N and NH3-N emissions and SIN storage) were positively correlated with SIN0-20, but negatively correlated with soil organic carbon / SIN0-20 (SOC/ SIN0-20). This study provides further evidence that biochar with an appropriate N application rate decreased SIN0-20 and increased DOC/SIN0-20, thus reducing SIN storage and the straw-induced gaseous N emissions without decreasing crop yields. 相似文献
47.
48.
S. C. Misra R. Randive V. S. Rao M. S. Sheshshayee R. Serraj P. Monneveux 《Journal of Agronomy and Crop Science》2006,192(5):352-362
Carbon isotope discrimination (Δ) and ash content (ma) have been proposed as indirect selection criteria for grain yield in wheat. The associations between Δ, ma and grain yield were found, however, to depend highly on the environmental conditions, the organ sampled and the time of sampling. In this study, carried out in the warm conditions of the Peninsular Zone of India, the relationship between Δ, ma and yield was studied in 30 bread and durum wheat cultivars under residual soil moisture stress (RSMS), post‐anthesis water stress (PAWS) and well‐watered (WW) conditions. Both Δ and ma were analysed in young seedlings (four‐leaf stage), leaves at anthesis and grain at maturity. Ash content was also evaluated in leaves at booting stage and maturity. Grain Δ was lower under PAWS and RSMS than under WW, while seedling and leaf Δ did not significantly differ among water regimes. Grain yield was positively correlated to grain Δ under PAWS and negatively correlated to grain ma under RSMS. A significant positive correlation was noted under RSMS and WW treatments between maLm and grain yield. Ash content in leaf at maturity consequently appears to be a useful indirect selection criterion in environments where Δ does not show any correlation with yield. The results highlight the potential of Δ and ma as indirect selection criteria for wheat yield in the conditions of the Peninsular Zone of India. 相似文献
49.
安溪茶园土壤矿质元素质量分数与土壤母质关系较为密切．其中Ｋ、Ａｌ的质量分数是凝灰岩母质＞ 花岗岩母质＞ 第四纪红土母质;Ｆｅ、Ｍｎ、Ｚｎ 质量分数是凝灰岩母质＞ 第四纪红土母质＞ 花岗岩母质．土壤有效性的矿质元素与铁观音乌龙茶的生化品质存在着密切的相关．如土壤中的有效Ｚｎ,活性Ａｌ与速效Ｐ的比值与茶叶的氨基酸总量呈显著或极显著正相关;活性Ｍｎ 与茶多酚呈显著的正相关;速效Ｐ、活性Ｆｅ、活性Ｍｎ与水浸出物和总糖质量分数呈显著或极显著的正相关． 相似文献
50.
台江采育场竹木混交林丰产措施试验 总被引：1，自引：0，他引：1
对台江林业采育场现有竹木混交林进行施肥和土壤垦复两种试验,结果表明,不同施肥处理虽有一定增产效果,但经方差分析未达到显著水平;不同土壤垦复措施的增产效果,以深翻加施肥的新竹产量最高,锄草松土居第二,单纯深翻并不理想,效果不如劈山抚育。因而,新兴竹木混交林应以调整竹林结构和护笋养竹为主,每年锄草松土即可达到材用丰产林标准,不宜盲目深翻、施肥。 相似文献