Soil salinization is a critical environmental issue restricting agricultural production.Deep return of straw to the soil as an interlayer (at 40 cm depth) has been a popular practice to alleviate salt stress.However,t...Soil salinization is a critical environmental issue restricting agricultural production.Deep return of straw to the soil as an interlayer (at 40 cm depth) has been a popular practice to alleviate salt stress.However,the legacy effects of straw added as an interlayer at different rates on soil organic carbon (SOC) and total nitrogen (TN) in saline soils still remain inconclusive.Therefore,a four-year (2015–2018) field experiment was conducted with four levels (i.e.,0,6,12and 18 Mg ha~(–1)) of straw returned as an interlayer.Compared with no straw interlayer (CK),straw addition increased SOC concentration by 14–32 and 11–57%in the 20–40 and 40–60 cm soil layers,respectively.The increases in soil TN concentration (8–22 and 6–34%in the 20–40 and 40–60 cm soil layers,respectively) were lower than that for SOC concentration,which led to increased soil C:N ratio in the 20–60 cm soil depth.Increases in SOC and TN concentrations in the 20–60 cm soil layer with straw addition led to a decrease in stratification ratios (0–20 cm:20–60 cm),which promoted uniform distributions of SOC and TN in the soil profile.Increases in SOC and TN concentrations were associated with soil salinity and moisture regulation and improved sunflower yield.Generally,compared with other treatments,the application of 12 Mg ha~(–1) straw had higher SOC,TN and C:N ratio,and lower soil stratification ratio in the2015–2017 period.The results highlighted that legacy effects of straw application as an interlayer were maintained for at least four years,and demonstrated that deep soil straw application had a great potential for improving subsoil fertility in salt-affected soils.展开更多
Light spectrum plays an important role in regulating the growth and development of in vitro cultured potato(Solanum tuberosum L.) plantlets. The status of potato plantlets at the end of in vitro stage influences the m...Light spectrum plays an important role in regulating the growth and development of in vitro cultured potato(Solanum tuberosum L.) plantlets. The status of potato plantlets at the end of in vitro stage influences the minituber production after transplanting. With 100 μmol m^-2s^-1 total photosynthetic photon flux density(PPFD), a light spectrum study of 100% red light emitting diodes(LEDs) light spectrum(RR), 100% blue LEDs light spectrum(BB), 65% red+35% blue LEDs light spectrum(RB), and 45% red+35% blue+20% green LEDs light spectrum(RBG) providing illumination at the in vitro cultured stage of potato plantlets for 4 weeks using fluorescent lamp as control(CK) was performed to investigate the effects of LEDs light spectrum on the growth, leaf anatomy, and chloroplast ultrastructure of potato plantlets in vitro as well as the minituber yield after 2 months transplanting in the greenhouse. Compared to CK, RB and RBG promoted the growth of potato plantlets in vitro with increased stem diameter, plantlet fresh weight, plantlet dry weight, and health index. Furthermore, BB induced the greatest stem diameter as well as the highest health index in potato plantlets in vitro. Root activity, soluble protein, and free amino acid were also significantly enhanced by BB, whereas carbohydrates were improved by RR. In addition, thickness of leaf, palisade parenchyma and spongy parenchyma was significantly increased by BB and RBG. Chloroplasts under BB and RBG showed well-developed grana thylakoid and stroma thylakoid. Unexpectedly, distinct upper epidermis with greatest thickness was induced and palisade parenchyma and spongy parenchyma were arranged neatly in RR. After transplanting in the greenhouse for 2 months, potato plantlets in vitro from BB, RB, and RBG produced high percentage of large size tuber. BB improved fresh and dry weights of the biggest tuber but decreased tuber number per plantlet. In addition, RBG increased tuber number as well as tuber fresh and dry weight slightly. Our results suggested monochromatic blue LEDs as well as combined red, blue or/and green LEDs light spectrum were superior to fluorescent lamp spectrum in micro-propagation of potato plantlets. Therefore, the application of RBG was suitable;BB and RB could be used as alternatives.展开更多
Leguminous crops play a vital role in enhancing crop yield and improving soil fertility. Therefore, it can be used as an organic N source for improving soil fertility. The purpose of this study was to(i) quantify the ...Leguminous crops play a vital role in enhancing crop yield and improving soil fertility. Therefore, it can be used as an organic N source for improving soil fertility. The purpose of this study was to(i) quantify the amounts of N derived from rhizodeposition, root and above-ground biomass of peanut residue in comparison with wheat and(ii) estimate the effect of the residual N on the wheat-growing season in the subsequent year. The plants of peanut and wheat were stem fed with 15 N urea using the cotton-wick method at the Wuqiao Station of China Agricultural University in 2014. The experiment consisted of four residue-returning strategies in a randomized complete-block design:(i) no return of crop residue(CR0);(ii) return of above-ground biomass of peanut crop(CR1);(iii) return of peanut root biomass(CR2); and(iv) return of all residue of the whole peanut plant(CR3). The 31.5 and 21% of the labeled 15 N isotope were accumulated in the above-ground tissues(leaves and stems) of peanuts and wheat, respectively. N rhizodeposition of peanuts and wheat accounted for 14.91 and 3.61% of the BG15 N, respectively. The 15 N from the below-ground 15 N-labeled of peanuts were supplied 11.3, 5.9, 13.5, and 6.1% of in the CR0, CR1, CR2, and CR3 treatments, respectively. Peanut straw contributes a significant proportion of N to the soil through the decomposition of plant residues and N rhizodeposition. With the current production level on the NCP, it is estimated that peanut straw can potentially replace 104 500 tons of synthetic N fertilizer per year. The inclusion of peanut in rotation with cereal can significantly reduce the use of N fertilizer and enhance the system sustainability.展开更多
基金funded by the National Natural Science Foundation of China (31871584)the Agricultural Science and Technology Innovation Program, Chinese Academy of Agricultural Sciences (CAAS-ZDRW202201)+2 种基金the Fundamental Research Funds for Central Non-profit Scientific Institution, China (1610132020011)the “Open the list” in charge of the Science and Technology Project of Ordos, Center for Agro-pastoral Ecology and Resource Conservation of Ordos City, Inner Mongolia, China (JBGS2021-001)the Inner Mongolia Autonomous Region Research Project (2021EEDSCXSFQZD011)。
文摘Soil salinization is a critical environmental issue restricting agricultural production.Deep return of straw to the soil as an interlayer (at 40 cm depth) has been a popular practice to alleviate salt stress.However,the legacy effects of straw added as an interlayer at different rates on soil organic carbon (SOC) and total nitrogen (TN) in saline soils still remain inconclusive.Therefore,a four-year (2015–2018) field experiment was conducted with four levels (i.e.,0,6,12and 18 Mg ha~(–1)) of straw returned as an interlayer.Compared with no straw interlayer (CK),straw addition increased SOC concentration by 14–32 and 11–57%in the 20–40 and 40–60 cm soil layers,respectively.The increases in soil TN concentration (8–22 and 6–34%in the 20–40 and 40–60 cm soil layers,respectively) were lower than that for SOC concentration,which led to increased soil C:N ratio in the 20–60 cm soil depth.Increases in SOC and TN concentrations in the 20–60 cm soil layer with straw addition led to a decrease in stratification ratios (0–20 cm:20–60 cm),which promoted uniform distributions of SOC and TN in the soil profile.Increases in SOC and TN concentrations were associated with soil salinity and moisture regulation and improved sunflower yield.Generally,compared with other treatments,the application of 12 Mg ha~(–1) straw had higher SOC,TN and C:N ratio,and lower soil stratification ratio in the2015–2017 period.The results highlighted that legacy effects of straw application as an interlayer were maintained for at least four years,and demonstrated that deep soil straw application had a great potential for improving subsoil fertility in salt-affected soils.
基金supported by the National High-Tech R&D Program of China (2013 AA 103005)
文摘Light spectrum plays an important role in regulating the growth and development of in vitro cultured potato(Solanum tuberosum L.) plantlets. The status of potato plantlets at the end of in vitro stage influences the minituber production after transplanting. With 100 μmol m^-2s^-1 total photosynthetic photon flux density(PPFD), a light spectrum study of 100% red light emitting diodes(LEDs) light spectrum(RR), 100% blue LEDs light spectrum(BB), 65% red+35% blue LEDs light spectrum(RB), and 45% red+35% blue+20% green LEDs light spectrum(RBG) providing illumination at the in vitro cultured stage of potato plantlets for 4 weeks using fluorescent lamp as control(CK) was performed to investigate the effects of LEDs light spectrum on the growth, leaf anatomy, and chloroplast ultrastructure of potato plantlets in vitro as well as the minituber yield after 2 months transplanting in the greenhouse. Compared to CK, RB and RBG promoted the growth of potato plantlets in vitro with increased stem diameter, plantlet fresh weight, plantlet dry weight, and health index. Furthermore, BB induced the greatest stem diameter as well as the highest health index in potato plantlets in vitro. Root activity, soluble protein, and free amino acid were also significantly enhanced by BB, whereas carbohydrates were improved by RR. In addition, thickness of leaf, palisade parenchyma and spongy parenchyma was significantly increased by BB and RBG. Chloroplasts under BB and RBG showed well-developed grana thylakoid and stroma thylakoid. Unexpectedly, distinct upper epidermis with greatest thickness was induced and palisade parenchyma and spongy parenchyma were arranged neatly in RR. After transplanting in the greenhouse for 2 months, potato plantlets in vitro from BB, RB, and RBG produced high percentage of large size tuber. BB improved fresh and dry weights of the biggest tuber but decreased tuber number per plantlet. In addition, RBG increased tuber number as well as tuber fresh and dry weight slightly. Our results suggested monochromatic blue LEDs as well as combined red, blue or/and green LEDs light spectrum were superior to fluorescent lamp spectrum in micro-propagation of potato plantlets. Therefore, the application of RBG was suitable;BB and RB could be used as alternatives.
基金supported by the National Natural Science Foundation of China[grant number 91544221],[grant number41571130024],[grant number 41675137],[grant number41505091]the LAPC Free Exploration Fund
基金supported by the National Natural Science Foundation of China(31671640)the Special Fund for Agro-scientific Research in the Public Interest,China(201503121-11)the National Key Research and Development Program of China(2016YFD0300205-01)
文摘Leguminous crops play a vital role in enhancing crop yield and improving soil fertility. Therefore, it can be used as an organic N source for improving soil fertility. The purpose of this study was to(i) quantify the amounts of N derived from rhizodeposition, root and above-ground biomass of peanut residue in comparison with wheat and(ii) estimate the effect of the residual N on the wheat-growing season in the subsequent year. The plants of peanut and wheat were stem fed with 15 N urea using the cotton-wick method at the Wuqiao Station of China Agricultural University in 2014. The experiment consisted of four residue-returning strategies in a randomized complete-block design:(i) no return of crop residue(CR0);(ii) return of above-ground biomass of peanut crop(CR1);(iii) return of peanut root biomass(CR2); and(iv) return of all residue of the whole peanut plant(CR3). The 31.5 and 21% of the labeled 15 N isotope were accumulated in the above-ground tissues(leaves and stems) of peanuts and wheat, respectively. N rhizodeposition of peanuts and wheat accounted for 14.91 and 3.61% of the BG15 N, respectively. The 15 N from the below-ground 15 N-labeled of peanuts were supplied 11.3, 5.9, 13.5, and 6.1% of in the CR0, CR1, CR2, and CR3 treatments, respectively. Peanut straw contributes a significant proportion of N to the soil through the decomposition of plant residues and N rhizodeposition. With the current production level on the NCP, it is estimated that peanut straw can potentially replace 104 500 tons of synthetic N fertilizer per year. The inclusion of peanut in rotation with cereal can significantly reduce the use of N fertilizer and enhance the system sustainability.
基金supported by the National Key Basic Research Program of China[grant number 2014CB447900]the National Natural Science Foundation of China[grant number 41305115]+2 种基金the Strategic Priority Research Program(B)of the Chinese Academy of Sciences[grant number XDB05020501]the Project of High-resolution Earth Observation System[grant number 05-Y30B02-9001-13/15-7-WX02]Commonwealth Project in Ministry of Environmental Protection[grant number 201309011]
文摘[目的]采用界面聚合法制备360 g/L异(口恶)草松微囊悬浮剂,筛选稳定配方。[方法]优选了配方溶剂、乳化体系、剪切时间、油相单体用量、水相单体种类和用量、密度调节剂,通过扫描电子显微镜观察了微囊形貌,检测了微囊的各项物化性能,进行了多批次配方验证。同时,进行田间药效试验验证。[结果]最终确定配方组成:异(口恶)草松32.5%(质量分数,其他同)、油酸甲酯4%、GT-27 2%、Borresperse NA 1%、黄原胶0.1%、四乙烯五胺1%、GY-D190.8%、GY-X60 0.15%、卡松0.15%、无水硫酸镁4%、去离子水补足100%。田间试验结果表明:药后40 d,对5种杂草鲜质量防效在75.98%以上,其中540 g a.i./hm^(2)处理总草鲜质量防效为89.71%,优于同剂量乳油防治效果。[结论]优选的360 g/L异(口恶)草松微囊悬浮剂配方稳定,除草效果良好,具有较大开发价值。
