滨海盐渍土抗虫棉养分吸收和干物质积累特点

以转Bt基因抗虫棉(Gossypium hirsutum L.)中早熟品种鲁棉研18和早熟品种鲁棉研19为材料,对黄河三角洲滨海盐渍土高、中、低产田抗虫棉的主要养分吸收、光合速率和干物质积累特点进行了研究。结果表明,中、低产田抗虫棉的主要养分吸收量显著低于高产田,而养分生理利用效率显著高于高产田。高、中、低产田抗虫棉的氮素生理利用效率分别为4.81、6.33和8.05 kg皮棉 kg^-1 N,磷素生理利用效率分别为28.57、40.06和50.48 kg皮棉 kg^-1 P,钾素生理利用效率分别为9.16、11.58和12.76 kg皮棉 kg^-1 K。养分吸收比例总体上N高于K,更明显高于P。中、低产田抗虫棉的净光合速率和生物产量明显低于高产田,皮棉产量也显著低于高产田,分别低12.44%和36.93%,但棉柴比显著高于高产田。表明滨海盐渍土中、低产田的盐分高而养分有效性和供应能力差,影响抗虫棉的养分吸收和光合作用,进而阻碍棉花生长发育和干物质积累。滨海盐渍土棉田经济施肥的原则是保证中、低产田的肥料供应,高产田重施P、K肥,低产田重施N、P肥。     

秸秆还田对滨海盐碱地棉苗光合特性及生长的影响

为探讨秸秆还田对滨海重度盐碱地棉苗光合特性及生长的影响,设置增施有机肥、播前秸秆还田、冬前秸秆还田3个处理,测定了棉花苗期3个层次土壤含盐量、水分和容重,棉花叶片光合参数、叶片SPAD值以及干物质积累和棉花产量。结果表明,与对照相比,增施有机肥和秸秆还田的处理各个土层含盐量和容重明显降低,棉苗叶片LAI和SPAD明显增大,光合能力提高,干物质积累量、根冠比以及棉花产量明显增加。其中,冬前秸秆还田各土层含盐量低于2.00 g·kg-1,容重保持在1.15~1.40 g·cm-3,叶片SPAD值高于40.0,LAI提高65.5%,光合性能系数增高23.4%~92.8%,非光化学淬灭系数(NPQ)降低12.2%,干物质积累总量增大46.3%,根冠比提高56.5%,产量提高36.2%。因此,在本试验条件下,冬前秸秆还田更有利于滨海盐碱地改良及棉苗的正常生长。     

黄河三角洲盐渍棉花施用氮、磷、钾肥的效应研究

为探讨盐渍土抗虫棉施用NPK肥的效应及其营养生理机制,指导滨海盐渍土抗虫棉合理施肥,在黄河三角洲盐渍土低、中、高盐棉田种植转Bt基因抗虫棉鲁棉研28,研究N、P、K肥配合施用对其养分吸收利用、Na⁺吸收积累、光合速率、干物质积累和产量的影响。结果表明,N、P肥配合,尤其是N、P、K肥配合施用显著增加了低、中、高盐田棉花的N、P、K养分吸收量,减少了Na⁺吸收积累量。低、中、高盐田棉花的N、P、K养分农学利用效率均以NPK配施的处理较高,氮养分农学利用效率分别为0.20、1.95和2.07 kg皮棉 kg^–1 N,磷养分农学利用效率分别为0.87、8.35和8.71 kg皮棉 kg^–1 P,钾养分农学利用效率分别为0.26、2.89和3.77 kg皮棉 kg^–1 K。N、P、K肥配合施用还维持了较高的棉株叶面积、叶绿素含量和净光合速率。低、中、高盐田棉花的生物产量和皮棉产量也均以NPK配施的处理较高,皮棉产量分别增产2.53%、28.67%和30.47%。中、高盐棉田的施肥效应明显好于低盐棉田。表明根据盐碱程度分类合理施肥是减轻盐渍土营养障碍、改善棉花营养、提高养分农学利用效率和棉花产量的有效途径。     

山东东营滨海盐渍棉田盐分与养分的季节性变化及对棉花产量的影响

在山东省东营市选择土壤盐分含量分别为0.15%、0.35%和0.50%的高、中、低产田各一块,种植中早熟品种鲁棉研18或早熟品种鲁棉研19,结合取盐碱土盆栽,研究了不同含盐量棉田的盐分、养分含量变化及棉花产量表现。结果表明,高产田有机质与碱解氮含量较高、有效磷含量偏低、有效钾含量中等,而低产田则表现出有机质少、贫氮、缺磷、富钾的特点。三类棉田的土壤盐分皆是春季和秋季高、夏季低,土壤有机质含量在整个生育季节内变化不大,而氮、磷、钾则随生育进程的推进呈逐渐减少的趋势。大田条件下,中、低产田比高产田分别减产10%~17%和27%~39%,而相应盐土盆栽条件下则分别减产2.8%和6.7%。     

不同种植方式对盐碱地棉花干物质质量及氮磷钾积累的影响

以中棉所79为材料,通过设置高垄覆膜、高垄不覆膜、喷洒土壤改良剂、喷洒土壤改良剂+高垄覆膜、喷洒土壤改良剂+高垄不覆膜和平作覆膜6种种植方式,研究不同种植方式对盐碱地棉花产量、干物质质量与氮磷钾积累的影响。结果表明,与平作覆膜种植方式相比,喷洒土壤改良剂和喷洒土壤改良剂+高垄覆膜处理子棉产量显著提高,增幅分别达45.88%和42.24%。进一步分析表明,这两种种植方式最有利于提高棉花干物质质量和氮、磷、钾的积累量。     

起垄覆膜与土壤脱盐剂对江苏沿海中重度盐碱地棉花成苗和产量的影响

以中棉所79为材料,于2012和2013年在江苏大丰稻麦原种场盐碱地设计高垄覆膜、高垄不覆膜、土壤脱盐剂+覆膜、土壤脱盐剂+高垄覆膜、土壤脱盐剂+高垄不覆膜和平作覆膜6个处理对棉花出苗、产量及与抗盐相关的生理指标影响。结果表明:与平作覆膜相比(CK),高垄覆膜+土壤脱盐剂能显著提高籽棉产量和促进出苗,产量比对照提高32.00%~113.78%;土表20 cm土壤盐分降低最多,下降42.07%,出苗率提高148.8%。同时高垄覆膜+土壤脱盐剂处理能有效地减少棉苗叶片丙二醛和脯氨酸的积累,降低叶片超氧化物歧化酶(SOD)活力。因此,高垄覆膜与土壤脱盐剂的应用,由于能有效降低中重度盐碱地的盐分,从而有利于棉花发芽出苗,降低盐分逆境对棉苗的胁迫效应,最终促进产量提高。     

节水灌溉对滨海盐渍土棉花生理生化变化和生长发育的影响

在自然条件下,安排了以灌水为主区、盖膜为副区的裂区试验,研究了灌水与盖膜处理对滨海盐渍土水分、盐分含量变化、棉花生理生化和生长发育的影响。结果表明,在不盖膜与盖膜两种条件下,土壤含水量均随灌水量的增加而增加,而土壤含盐量随之降低,由此形成了"土壤脱盐淡化层";棉花生理生化和生长发育均受水、盐胁迫的影响,但灌水量1500m3·hm 2与2250m3·hm 2处理间无显著差异;从节水和高效角度考虑,以地膜覆盖度50%、灌水量1500m3·hm 2处理最佳。     

滨海盐碱地棉花秸秆还田和深松对棉花干物质积累、养分吸收及产量的影响

以鲁棉研36号为试验材料,在滨海盐碱地设置常规耕作(CT)、深松(ST)、秸秆还田(SR)、秸秆还田+深松(SRT)4个处理,研究棉花秸秆还田和深松对棉花产量、0～40 cm土层含盐量、棉花干物质积累动态、氮(N)磷(P)钾(K)养分积累和分配特性的影响。结果表明,秸秆还田在2年试验内均可增加棉花产量, SR产量比CT增加33.9%, SRT比ST增加32.1%;深松在2017年增加了棉花产量, 2018年对产量无影响。秸秆还田在2年试验中均降低0～40 cm土层含盐量, SR的含盐量在棉花生育后期比CT降低22.4%, SRT的土壤含盐量比ST降低20.7%;深松在2年试验内对20～40cm土层含盐量的影响不一致,ST含盐量在2017年棉花生育后期比CT降低16.5%,但在2018年深松对土壤含盐量无影响。棉花干物质和N、P、K积累动态均符合Logistic生长曲线。棉花秸秆还田后增加了棉花干物质和N、P、K的最大积累量, SR的干物质、N、P、K最大积累量比CT分别提高35.5%、38.3%、53.4%和55.0%, SRT比ST分别提高27.0%、30.7%、21.2%和42.4...     

黄河三角洲盐渍土棉花施用氮、磷、钾肥的效应研究

为探讨盐渍土抗虫棉施用氮(N)、磷(P)、钾(K)肥的效应及其营养生理机制,指导滨海盐渍土抗虫棉合理施肥,在黄河三角洲盐渍土低、中、高盐棉田种植转Bt基因抗虫棉鲁棉研28,研究N、P、K肥配合施用对其养分吸收利用、Na+吸收积累、光合速率、干物质积累和产量的影响。结果表明,N、P肥配合,尤其是N、P、K肥配合施用显著增加了低、中、高盐田棉花的N、P、K养分吸收量,减少了Na+吸收积累量。低、中、高盐田棉花的N、P、K养分农学利用效率均以N、P、K配施的处理较高,氮养分农学利用效率分别为0.20、1.95和2.07kg皮棉kg-1N,磷养分农学利用效率分别为0.87、8.35和8.71kg皮棉kg-1P,钾养分农学利用效率分别为0.26、2.89和3.77kg皮棉kg-1K。N、P、K肥配合施用还维持了较高的棉株叶面积、叶绿素含量和净光合速率。低、中、高盐田棉花的生物产量和皮棉产量也均以N、P、K配施的处理较高,皮棉产量分别增产2.53%、28.67%和30.47%。中、高盐棉田的施肥效应明显好于低盐棉田。表明根据盐碱程度分类合理施肥是减轻盐渍土营养障碍、改善棉花营养、提高养分农学利用效率和棉花产量的有效途径。     

笋菜在滨海粘质盐土种植技术

台州市路桥区滨海盐渍土,土层深厚,质地粘重,绝大部份是轻粘土.1m土体盐分含量在1.0～6.0g/kg,pH值8.0以上,碳酸钙含量70g/kg左右;表层土壤有机质、碱解氮、速效磷含量较低,铁、锰、锌等元素多为不溶性化合物,速效钾含量丰足,属滨海粘质盐土.这种土壤适宜种植何种作物,经多年试验表明,笋菜是适宜种植的作物之一.     

Effects of Soil Salinity and Plant Density on Yield and Leaf Senescence of Field‐Grown Cotton

The response of cotton to constant salinity has been well documented under controlled conditions, but its response to changing salinity under field conditions is poorly understood. Using a split‐plot design, we conducted a 2‐year field experiment to determine the effects of soil salinity and plant density on plant biomass, boll load, harvest index and leaf senescence in relation to cotton yield in three fields with similar fertility but varying salinity. The main plots were assigned to weak (electrical conductivity of soil saturated paste extract, ECe = 5.5 dS m^?1), moderate (ECe = 10.1 dS m^?1) and strong (ECe = 15.0 dS m^?1) soil salinity levels, while plant density (3.0, 4.5 and 7.5 plants m^?2) was assigned to the subplots. Soil salinity had a negative effect on seedcotton yield, but the negative effect was compensated for by increased plant density under strong‐salinity conditions. Seedcotton yield under weak salinity changed little with varying plant density, but the medium plant density yielded better than the low or high plant density under moderate salinity. Plants accumulated 49 and 112 % more Na⁺ in leaves under moderate and strong salinity than under weak salinity. Strong salinity also led to higher boll load and early leaf senescence. Plant density had no effect on Na⁺ accumulation in leaves, but greatly reduced boll load and delayed leaf senescence. Plant biomass, maximum leaf area index and harvest index were greatly affected by salinity, plant density and their interaction. Accelerated leaf senescence under strong salinity was attributed to the high boll load and increased accumulation of toxic ions like Na⁺ in leaves, while delayed leaf senescence with increased plant density was attributed to the reduced boll load. Optimal yield can only be obtained with proper coordination of total biomass and harvest index by modification of plant density based on salinity levels.     

Unequal salt distribution in the root zone increases growth and yield of cotton

Soil salinity is often heterogeneous, yet plant response to unequal salt distribution (USD) in the root zone is seldom studied in cotton (Gossypium hirsutum L.). Our objective was to evaluate the effects of USD on growth and yield, as well as its potential application for increasing cotton production. To achieve this objective, greenhouse and field experiments were conducted. In the first experiment, potted cotton plants were grown in a split-root system in the greenhouse. Each root half was irrigated with either the same or two concentrations of NaCl. Plant biomass, leaf chlorophyll (Chl), photosynthesis (Pn) and transpiration (Tr), Na⁺ and K⁺ accumulation, as well as biological and economic yields were determined. In the second experiment, plants were grown in furrow-beds in saline fields with those grown on flat beds as controls. Root-zone salinity, yield and yield components and earliness (the percentage of the first two harvests to total harvests) were monitored. When the entire root system was exposed to the same concentration of NaCl, shoot dry weight, leaf area, plant biomass, leaf Chl, Pn and Tr were markedly reduced relative to the NaCl-free control at 2 weeks after salinity stress (WAS). Significant reductions in biological (23.6–73.8%) and economic yields (38.1–79.7%) were noticed at harvest. However, when only half of the root system was exposed to low-salinity, the inhibition effect of salinity on growth and yield was significantly reduced. Plant biomass and seed cotton yield were increased by 13 and 23.9% with 50/150 mM/mM NaCl, 40 and 44.5% with 100/300 mM/mM NaCl, and 85.7 and 127.8% with 100/500 mM/mM NaCl relative to their respective equal salt distribution (ESD) controls (100/100, 200/200, and 300/300). Unequal salt distribution also decreased concentrations of Na⁺ and increased leaf K⁺ and Chl content, K⁺/Na⁺ ratio, Pn and Tr, compared with ESD. Furrow-bed seeding induced unequal distribution of salts in the surface soil during the field experiment. Under furrow planting, soil salinity was much higher, but soil osmotic potential was much lower on the ridged part than the furrows. Yield and earliness were increased 20.8 and 5.1% by furrow seeding relative to flat seeding. These enhancements were mainly attributed to unequal distribution of salts in the root zone. Thus, specific cultural practices that induce unequal salt distribution such as furrow-bed seeding can be used to improve cotton production in saline fields.     

不同土壤水分条件下棉花库源比变化对产量形成的调节效应

在新疆气候生态条件下,以不同叶型棉花品种为材料,设置不同土壤水分处理,采用人工减源疏库的方法,研究不同土壤水分条件下库源比变化对棉花产量形成的影响。结果表明,中叶型品种新陆早13号在中水(控制0～60 cm土壤相对含水量的下限为田间持水量的70%～75%)条件下,叶源轻度胁迫显著增强剩余叶片光合能力,但光合物质累积量及向生殖器官的分配率和单株结铃数、铃重均未发生明显变化,子棉产量与对照无明显差异;鸡脚叶型品种标杂A1在高水(控制0～60 cm土壤相对含水量的下限为田间持水量的85%～90%)条件下,库容轻度胁迫后叶片光合速率和光合物质累积量与对照无明显差异,但光合产物向蕾铃的分配加快,铃重增大,子棉产量有所增加;小叶型品种新陆早10号减源或疏库后子棉产量均显著低于对照。因此,依据不同类型棉花源库关系对土壤水分的响应不同,通过棉田水分管理对源库进行调节,建立合理的库源比,可进一步提高水分利用效率和棉花产量。     

Cotton Response to Salinity and Different Potassium-Sodium Ratio in Irrigation Water

The present study was designed to investigate cotton response to different salinity levels at different K/Na ratios of irrigation water.
The salinity levels in irrigation water were 3200 and 6400 mg/1 and the control treatment had a 320 mg/L. Potassium/Sodium ratios in irrigation water were 1: 9 and 1: 4.
Some agronomic traits were studied as well as leaf water Potential (LWP), and leaf samples were taken for elemental analysis.
Statistical analysis showed that increasing total salinity of irrigation water reduced seed yield and total dry weight of cotton but not number of total or open bolls. Lower K/Na ratio (1:9) was of benificial effects on most agronomic traits.
Increasing salinity of irrigation water caused an increase in Na, but not K or Ca content of the cotton leaves; while decreasing K/Na ratio in the saline irrigation water decreased the K/Na ratio in the leaves. Lower leaf water potential was found to be associated with higher levels of both water salinity and K/Na ratio.
A strong relationships were found between cotton seed yield, LWP and K/total bases content in leaves. Ionic content relations (K/Na and K/total bases content) were found to be of a strong association with LWP.
In brief, it could be concluded that increasing K to certain extent; K/Na (1: 9) could be useful in irrigating cotton plant with high water salinity.
The benificial effects of potassium additions to diminish the salinity effects in cotton may be the consequence of improved plant water relations, as well as the status of ion relationships.     

Improved salt tolerance and seed cotton yield in cotton (<Emphasis Type="Italic">Gossypium hirsutum</Emphasis> L.) by transformation with <Emphasis Type="Italic">betA</Emphasis> gene for glycinebetaine synthesis

Homozygous transgenic cotton (Gossypium hirsutum L.) plants that accumulated glycinebetaine (GB) in larger quantities were more tolerant to salt than wild-type (WT) plants. Four transgenic lines, namely 1, 3, 4, and 5, accumulated significantly higher levels of GB than WT plants did both before and after salt stress. At 175 and 275 mM NaCl, seeds of all the transgenic lines germinated earlier and recorded a higher final germination percentage, and the seedlings grew better, than those of the WT. Under salt stress, all the lines showed some characteristic features of salt tolerance, such as higher leaf relative water content (RWC), higher photosynthesis, better osmotic adjustment (OA), lower percentage of ion leakage, and lower peroxidation of the lipid membrane. Levels of endogenous GB in the transgenic plants were positively correlated with RWC and OA. The results indicate that GB in transgenic cotton plants not only maintains the integrity of cell membranes but also alleviates osmotic stress caused by high salinity. Lastly, the seed cotton yield of transgenic lines 4 and 5 was significantly higher than that of WT plants in saline soil. This research indicates that betA gene has the potential to improve crop’s salt tolerance in areas where salinity is limiting factors for agricultural productivity.     

Saponin seed priming improves salt tolerance in quinoa

Quinoa (Chenopodium quinoa Willd.) is a facultative halophyte of great value, and World Health Organization has selected this crop, which may assure future food and nutritional security under changing climate scenarios. However, germination is the main critical stage of quinoa plant phenology affected by salinity. Therefore, two experiments were conducted to improve its performance under salinity by use of saponin seed priming. Seeds of cv. Titicaca were primed in seven different solutions with varying saponin concentrations (i.e. 0%, 0.5%, 2%, 5%, 10%, 15%, 25% and 35%), and then, performances of primed seeds were evaluated based on mean germination time and final germination percentage in germination assays (0 and 400 mM NaCl stress). Saponin solutions of 10%, 15% and 25% concentration were found most effective priming tools for alleviating adverse effects of salt stress during seed germination. Performances of these primed seeds were further evaluated in pot study. At six‐leaf stage, plants were irrigated with saline water having either 0 or 400 mM NaCl. The results indicated that saline irrigation significantly decreased the growth, physiology and yield of quinoa, whereas saponin priming found operative in mitigating the negative effects of salt stress. Improved growth, physiology and yield performance were linked with low ABA concentration, better plant water (osmotic and water potential) and gas relations (leaf photosynthetic rate, stomatal conductance), low Na⁺ and high K⁺ contents in leaves. Our results suggest that saponin priming could be used as an easy‐operated and cost‐effective technology for sustaining quinoa crop growth on salt‐affected soils.     

盐渍和涝渍对棉苗生长和叶片某些生理性状的复合效应

 以陆地棉鲁棉研17和鲁棉研28为材料,以无盐正常供水为对照,研究了在盐渍、涝渍和盐涝复合胁迫14 d后棉苗干物质积累、叶片光合速率、叶绿素荧光参数和叶绿素含量等的变化。结果表明,盐渍、涝渍和盐涝复合胁迫都显著影响两个品种的光合速率和干物质积累。盐渍对棉苗的影响程度小于涝渍,而涝渍又小于盐涝复合胁迫,盐涝双重胁迫对棉苗生长和干物质积累的抑制表现出累加效应。盐渍胁迫下叶绿素含量的下降是光合作用受抑制的重要原因,而涝渍和盐涝胁迫下光合速率下降可能是叶绿体结构和PSⅡ稳定性的下降引起的。