东莞市土壤中多环芳烃的含量、代表物及其来源

2002年10~12月采集东莞市各地土壤样品64个,采用气相色谱-质谱仪对土壤中的16种优先控制的多环芳烃(PAHs)进行分析。结果显示,东莞市土壤中16种PAHs平均含量413μg/kg,含量较高的几种组分分别是菲、萤蒽、屈、苯并[b]萤蒽、芘。与PAHs总含量相关性较好的7种组分分别为屈、苯并[a]蒽、苯并[b]萤蒽、苯并[k]萤蒽、苯并[a]芘、茚并[1,2,3]芘、二苯并[a,h]蒽;所有相关系数R2均超过0.9000,可作为东莞市土壤中PAHs的代表物。北部平原水乡的PAHs污染明显高于南部丘陵山区、水乡上游保护区以及中部过渡带。化石燃料高温燃烧产物的大气沉降为东莞市土壤中PAHs的主要来源。东莞市农业土壤中PAHs含量显著低于天津市受污染严重的农业土壤。     

浑水灌溉和有机肥对土壤水分运移、蒸发及淋溶的影响

为揭示浑水含沙率和有机肥对土壤水分入渗和淋溶损失的影响,该研究采用室内一维土柱入渗装置,研究4个浑水含沙率水平（0、4%、8%、12%）和4个生物有机肥施肥水平（0、2 250、4 500、6 750 kg/hm²）对土壤水分运移、蒸发特性及淋溶损失的影响。结果表明：随着浑水含沙率和施肥水平的增大,相同时间内湿润锋运移距离和累积入渗量逐渐降低,且湿润锋运移距离与入渗时间符合幂函数关系。Kostiakov入渗模型可描述浑水灌溉和施肥条件下的土壤水分入渗变化过程（R²>0.9）,随着浑水含沙率和施肥水平的逐渐增大,入渗系数逐渐减小,而入渗指数逐渐增大。浑水灌溉和施肥条件下的累积蒸发量与蒸发时间符合Black和Rose蒸发模型（R²>0.9）,且Black模型的精度比Rose高。与清水入渗相比,浑水入渗可提高土壤中的电导率、有机质含量、淋溶液中的电导率和总溶解性固体物质,同时降低累积蒸发量、土壤的含水率、pH值和累积淋溶液体积。与不施肥相比,施有机肥能减少土壤水分的蒸发,同时还能降低累积淋溶液体积以及淋溶液中的电导率和总溶解性固体物质,增加土壤中的有机质含量和电导率。该研究结果可为浑水灌溉高效利用和合理施用有机肥量提供科学参考。     

去除有机质对城市浅水湖泊氮磷释放特征的影响

[目的] 分析南昌市浅水湖泊象湖表层沉积物的释放特征及有机质对氮、磷释放的影响,为城市内浅水湖泊治理中富营养化控制提供理论依据。[方法] 通过释放动力学试验以及释放潜能试验研究了城市浅水湖泊氨氮（NH₄⁺-N）和溶解性活性磷（SRP）的释放特征,以及与通过H₂O₂去除有机质后的释放特征进行了对比。[结果] 去除前后的氮磷的释放速率都是先由一个较快的过程逐渐变慢最后趋于稳定达到最大释放量（Q_max）。去除有机质后NH₄⁺-N的释放平衡时间缩短,SRP则几乎不变。去除有机质后,NH₄⁺-N的最大释放量（Q_max）与有机质含量呈显著正相关,而SRP与有机质无显著相关性。[结论] 影响沉积物氮磷释放的因素多样,其中高等水生植物丰富的区域对磷的释放有明显的抑制作用。沉积物有机质的含量越高沉积物氮的最大释放量（Q_max）也越高,磷的的最大释放量（Q_max）则受有机质含量、活性、组成成分、吸附与结合的铁铝磷含量等因素共同影响。     

红壤侵蚀区不同地层背景马尾松林土壤理化特性及细菌多样性

[目的] 揭示土壤理化特性与细菌丰度之间的内在关系,为红壤侵蚀区马尾松林水土流失分区精准治理提供参考。[方法] 以福建省长汀县红壤侵蚀区马尾松林为研究对象,选择侏罗系中统漳平组中段(J₂Z²)、侏罗系中统漳平组下段(J₂Z¹)、侏罗纪燕山期早期侵入岩(γ₅^{2(3) c})、第四系全新统(Q_h)4种地层背景,分析测定不同地层背景马尾松林土壤理化特性和细菌群落组成及多样性。[结果] 不同地层背景马尾松林土壤理化指标整体表现为：J₂Z¹＞J₂Z²＞Q_h＞γ₅^{2(3) c};土壤养分含量各地层背景各有丰缺,J₂Z¹地层背景土壤有机质含量大于其他地层,Q_h地层背景氮含量大于其他地层,而γ₅^{2(3) c}地层背景磷和钾含量较高;4种地层背景土壤细菌差异操作分类单元(OTU)数目表现为：Q_h＞J₂Z²＞J₂Z¹＞γ₅^{2(3) c},分别占总OTU数目的21.62%,18.29%,16.79%,12.08%;细菌群落多样性表现为：J₂Z²＞Q_h＞γ₅^{2(3) c}＞J₂Z¹;J₂Z¹地层和Q_h地层土壤细菌多样性与土壤含水率和土壤pH值正相关,J₂Z²地层与土壤容重以及全磷含量正相关,γ₅^{2(3) c}地层与土壤钾含量和速效氮含量正相关。[结论] 红壤侵蚀区不同地层背景马尾松林土壤理化特性存在一定差异,在植被恢复过程中应考虑地层背景因素进行分区治理,细菌对不同地层背景土壤性质具有一定指示作用。     

混合菌降解土壤中多环芳烃的试验研究

PAHs生物降解程度受多种因素影响。通过筛选驯化PAHs降解菌,研究混合菌对土壤中菲、芘、苯并（a）蒽、苯并（b）荧蒽、苯并（k）荧蒽、茚并（1,2,3-cd）芘的生物降解性能,并考察污染时间对土壤中PAHs降解效果的影响。结果表明,筛选的混合菌具有很强的PAHs降解能力,缩短了PAHs生物降解的半衰期,且PAHs起始降解速率较快,之后趋于平缓。27d内土壤中的菲、芘、苯并（a）蒽、苯并（b）荧蒽、苯并（k）荧蒽、茚并（1,2,3-cd）芘的平均降解率分别为98.14%、89.97%、88.47%、63.55%、65.24%、60.49%,其中菲在5d之内的降解率高于93%。污染210d的土壤中各PAHs的起始降解速率高于污染50d的土壤,因此污染时间越长,PAHs生物降解的停滞期越短。     

三峡库区紫色砂岩不同发育程度土壤入渗特征及其影响因素

为探究典型母岩不同发育程度土壤入渗特征,在三峡库区王家桥小流域采用圆盘入渗仪测定新成土（S1）、雏形土（S2）、淋溶土（S3）3种紫色砂岩不同发育程度土壤入渗过程,探究入渗过程的影响因素,并用3种常用模型进行入渗过程模拟,分析比较这些模型的适宜性。结果表明：（1）不同发育程度间土壤理化性质差异显著。雏形土和淋溶土土壤容重较新成土分别增加10.71%,19.50%,土壤总孔隙度分别降低8.79%,18.69%,通气孔隙度分别降低67.40%,8.16%,土壤黏粒含量分别增加10.01%,38.36%,砂粒含量分别减小8.09%,48.29%,土壤有机质分别增加2.88%,8.68%。（2）不同发育程度土壤间初始入渗率、平均入渗率、饱和导水率均表现为新成土>雏形土>淋溶土,雏形土、淋溶土平均入渗率及饱和导水率分别是新成土的0.99,0.58和0.89,0.83倍。（3）不同发育程度土壤理化性质差异对土壤入渗具有显著影响,土壤入渗速率与总孔隙度、毛管孔隙度、通气孔隙度、砂粒含量呈正相关关系,与容重、黏粒含量、有机质含量呈负相关关系。（4） Horton模型对紫色砂岩不同发育程度土壤入渗过程拟合效果最优（R²=0.942）,Kostiakov模型次之（R²=0.858）,Philip模型拟合效果较差（R²=0.832）。通过观测与模拟不同发育程度土壤入渗过程,研究结果可为流域土壤水分运移规律探究提供有益借鉴。     

南京有机污染风险区农田土壤多环芳烃污染状况研究

采集南京地区不同有机污染风险区农田表层土壤,用超快速液相色谱仪检测样品中15种EPA优控的多环芳烃(PAHs)含量。结果表明,被检农田土壤多环芳烃总量分布于306.0~1251.3μg kg~(-1)之间,均值682.0μg kg~(-1),四环以上高环多环芳烃占较大比例(80%)。根据欧洲土壤质量标准,所检土壤样本已达污染水平。不同风险污染区农田土壤PAHs的含量由高至低为:钢铁工业区、有机垃圾处理区、化工工业区及炼油工业区。钢铁工业区附近主要的污染物为荧蒽、芘、屈和苯并[a]蒽,分别占到污染物总量的16%、13%、10%和10%。采用荧蒽/(荧蒽+芘)与茚并[1,2,3-cd]芘/(茚并[1,2,3-cd]芘+苯并[g,h,i]苝)比值对各地污染物来源进行分析,结果发现调查区域的PAHs污染物以燃烧源为主,生物质燃料为主要污染物,部分地区同时有石油燃烧污染。     

HDXRF法农田土壤镉测定结果准确度评价与精准校正模型构建

以甘肃白银某污灌区重金属污染农田土壤为研究对象，对影响高精度便携式X荧光光谱（HDXRF）法总镉（Cd_T）测定精度的主要因素进行了筛选，分别研究了土壤水分、有机质类型与含量、土壤类型对HDXRF法Cd_T测定的影响，并采用相对误差（RE）、相对标准偏差（RSD）和决定系数（R²）对测定结果的准确度和精密度进行了评价。结果表明：HDXRF法Cd_T测定的RE≤10%、RSD≤10%、R²>0.99，符合农田土壤环境质量监测技术规范和美国环境保护署标准的准确度和精密度规定。HDXRF法Cd_T测定结果随着土壤水分含量的增加呈指数衰减趋势，衰减方程为y=0.803e^–1.3284x，衰减系数（μ_ω）为–1.328 4，R²为0.984 5。HDXRF法Cd_T测定结果与有机质含量呈显著的负相关关系（r=–0.955），且腐殖酸（HA）比泥炭（Peat）对测定结果的影响更大，HA与测定结果的校正方程为y=–1.555x +0.780，R²为0.934 4。土壤类型对HDXRF法Cd_T测定结果存在一定的影响，相对于红壤和水稻土，灰钙土的测定结果与传统实验室分析方法测定结果更接近。总之，虽然HDXRF法Cd_T测定结果受多种因素影响，但通过校正模型校正，其校正结果的可靠性能够满足Cd污染农田土壤精准调查需求。     

土壤中苯并[a]芘对白符跳(Folsomia candida)的生态毒性研究

苯并(a)芘（B[a]P）是一种典型的多环芳烃（PAHs）,在油田周边和污灌区土壤中有较高的检出率。在污染土壤生态风险评估和制定土壤生态基准时,常用土壤跳虫作为敏感生态受体,但已有研究表明,目前常用的成虫生长率、死亡率和繁殖率等指标特征往往仅对土壤中高剂量B[a]P产生毒性响应。采用白符跳（Folsomia candida）的生态毒理试验筛选可用于较低剂量B[a]P下新的敏感指标特征,并比较其在两种典型地带性土壤天津潮土和鹰潭红壤之间的敏感性差异。结果表明,幼虫的生长指标最敏感,能对土壤较低浓度B[a]P产生毒性响应,可作为指示土壤B[a]P毒性的指标。四个指标的敏感度依次为：幼虫体长>成虫体长>繁殖数>存活数。B[a]P对白符跳的毒性效应在两种土壤类型间存在显著差异（红壤和潮土中幼虫体长的最低效应浓度（LOEC）值分别为1和500 mg kg^-1）,可能受土壤理化性质,特别是有机质含量和pH的影响,在制定土壤生态基准时需对不同土壤的毒性数据进行归一化校正。     

脱硫石膏与聚谷氨酸配施对盐碱化土壤的改良效果

[目的] 探究脱硫石膏与聚谷氨酸（γ-PGA）配施对盐碱化土壤的改良效果,为改良西北地区盐碱化土壤提供理论和技术依据。[方法] 通过土柱模拟淋溶试验和盆栽模拟生长试验,从促进盐分淋洗,降低土壤含盐量,降低土壤pH值,改善土壤养分状况,促进作物生长的角度对脱硫石膏和γ-PGA配合施用对盐碱地的改良效果进行研究。[结果] 脱硫石膏与γ-PGA配施能进一步降低淋后土壤的pH值,提高Na⁺淋洗;可降低淋洗后HCO₃^-和Cl^-的含量,但提高淋洗后土壤SO₄^2-,Ca²⁺和Mg²⁺含量;有效降低淋后土壤钠吸附比（SAR）值。盆栽试验表明脱硫石膏与γ-PGA配施可显著增加玉米的株高、叶面积和干重,其中生长30 d时该处理玉米干重达到最大值,较对照处理增加了54.40%,较单施脱硫石膏和γ-PGA处理分别增加了40.27%和29.47%。此外,脱硫石膏与γ-PGA配施植株收获后土壤的pH值更低,且土壤N,P,K养分含量和土壤酶活性更高。[结论] 脱硫石膏和γ-PGA配施能起到较好的互补增效作用,进一步促进了土壤离子交换,降低了pH值,提高了土壤养分含量,促进了作物生长。     

Silicon Effect on Nutrient Acquisition of Peanut (Arachis hypogaea L.) Under Aluminum Stress

Aluminum (Al) toxicity represents one of the main yield-limiting factors for crops in acid soils. Silicon (Si) is known to increase tolerance in higher plants. This study was conducted to determine whether treatment with Si could improve nutrient uptake by peanut under Al stress. Peanut (Arachis hypogaea L. cv Zhonghua 4) was raised with or without Si (1.5 mM) in the growth chamber under 0 and toxic Al (0.3 mM) levels. Aluminum stress significantly decreased the root- and total-dry weight by 52.4% and 32.0%, respectively. The content of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) was significantly decreased, but that of Al increased markedly in shoots and roots after Al exposure at seedling, flower-needle, and pod-setting stage. Silicon alleviates Al toxicity in peanut plants in relation to Al distribution and allocation of tissue P, K, Ca, and Mg by favoring the partitioning of dry mass to roots.     

Trace Metal Contamination During Grinding of Plant Samples

Inductively coupled plasma-mass spectroscopic (ICP-MS) analysis of leaves from 22 cabbage crops in the Sa P? and B?c Hà districts of Láo Cai Province, North-Western Vi?t Nam, revealed unexpectedly high concentrations of chromium (Cr) and nickel (Ni). The concentrations were strongly linearly related (r² = 0.94), indicating sample contamination during grinding through a stainless-steel hammer mill. We tested this hypothesis in two ways. First, brown rice ground through the same mill was contaminated not only by Cr and Ni, but also cobalt (Co), iron (Fe) and molybdenum (Mo). Second, scanning electron microscopy/energy dispersive analysis of x-rays (SEM/EDS) of the ground samples revealed small fragments with co-located Fe, Cr and Ni, consistent with stainless steel wear fragments. Other grinders may perform differently and we suggest that quality assurance protocols for trace metal analysis of plants should include testing for grinder wear metals. Lastly, brown rice appears to be convenient for investigating contamination of plant tissues during grinding.     

Effects of humic acid on remediation of the nutritional deficiency of gerbera in hydroponic culture

Information is scant on the effect of humic acid (HA) on physiological, antioxidant and photosynthesis attributes of gerbera plants undergoing nutrient deficiency in culture solution. Gerbera plants cv. Malibu were grown in a factorial experiment based on a completely randomized design with 3 replications, using 3 different nutrient solutions [complete nutrient solution (NSc), 25% NSc (NS1), and 50% NSc (NS2)] treated with 2 levels of humic acid [0 (HA0) and 500 mg/l (HA1)].The interaction effect of HA and NS showed that HA improved the flower number in NSc, the transpiration in NS1+HA1, photosynthesis rate in NSc+HA1, stomatal conductance (gs) in NS2, mesophyll conductance of leaves in all NS levels and photosynthetic water use efficiency in NSc+HA1. The interaction effect of nutrient solution and HA on antioxidant activity was inconclusive, malondialdehyde content was the highest in NS2 and the lowest in NS1+HA1. The peroxidase activity increased in complete nutrient solution with and without HA and there were no differences among other treatments. Superoxide dismutase activity increased in NS1 and complete nutrient solution with HA and reached the highest in NSc. Humic acid was more effective in nutrient uptake, i.e., nitrogen, phosphorus, potassium, calcium, zinc, and iron (N, P, K, Ca, Zn, and Fe) in complete nutrient solution compared to NS1 and NS2. Conclusively, humic acid can compensate the nutrient deficiency stress of the culture solution in regards to protein synthesis, photosynthesis attributes regardless of the nutrient uptake of gerbera.     

氮磷钾不同配比对饲用稻威优198产量及糙米蛋白含量的影响

采用田间小区试验研究“推荐配比”(N:P2O5:K2O比率为190:90:100 kg hm-2)、“高氮量配比”(N:P2O5:K2O比率为210:90:100 kg hm-2)、“低氮量配比”(N:P2O5:K2O比率为170:90:100 kg hm-2)以及“常规配比”(N:P2O5:K2O比率为216:112.5:202.5 kg hm-2)4种氮、磷、钾配比施肥对饲用稻威优198蔗糖合成酶(SUS)、腺苷二磷酸焦磷酸化酶(AGPase)、硝酸还原酶(NR)、谷氨酰胺合成酶(GS)以及产量和糙米蛋白质的影响。结果表明:“推荐配比”能提高不同生育时期水稻功能叶(旗叶)和粒籽中碳、氮代谢关键酶的活性,这些关键酶活性的变化显著影响水稻产量和糙米全氮以及蛋白氮的含量。统计(P0.05)结果证实“推荐配比”能提高水稻产量达到8200 kg hm-2,与“常规配比”相比产量提高了24.81%;“推荐配比”糙米全氮和蛋白氮含量分别达到22.70 g kg-1和21.98 g kg-1,与“常规配比”相比差异显著,并且其全氮和蛋白氮含量分别提高17.01%,18.38%。     

小反刍兽疫N蛋白单克隆抗体的制备及竞争ELISA方法的建立

小反刍兽疫(PPR)是由小反刍兽疫病毒(PPRV)引起的一种危害严重的急性接触性传染病。为了检测血清中存在的抗PPRV的抗体,本研究利用纯化后的真核表达的PPRVN蛋白重组蛋白(rBacmid-PPRN)作为免疫原免疫BALB/c小鼠(Mus musculus),并使用原核表达的PPRVN蛋白重组蛋白(rpET-PPRN)作为间接ELISA检测抗原,共筛选得到8株抗PPRVN蛋白的单克隆抗体(mAb)。其中1D5单抗腹水效价达1∶106,分泌单抗亚类为IgG2b。以1D5作为竞争抗体、纯化后的rpET-PPRN蛋白作为包被抗原,建立了检测小反刍兽疫血清抗体的单抗竞争性ELISA(c-ELISA)方法。所建立的c-ELISA方法能够特异性的区分牛瘟阳性血清和小反刍兽疫阳性血清,并具有较高的灵敏度和特异性。应用建立c-ELISA检测方法检测共129份山羊(Capra hircus)血清样品,与标准c-ELISA试剂盒的符合率为96.9%。本研究成功地建立了可特异性检测动物血清中抗PPRV抗体的竞争性ELISA方法,对小反刍兽疫的诊断、疫苗免疫水平的监控及控制其流行具有重要意义。     

四种常规方法提取伊利石有效钾的机制比较

采用化学分析、X射线衍射、中红外光声光谱以及原子力显微镜的方法,比较了0.2 mol L~(-1)四苯硼钠法、1 mol L~(-1)沸硝酸法、2 mol L~(-1)冷硝酸法和2 mol L~(-1)热盐酸法浸提伊利石中有效钾的机制。结果表明,四苯硼钠法浸提时,伊利石中钾素释放量达到全钾量的59.5%,且基本均通过层间交换反应予以释放,结构离子铁、铝和硅释放量极低;采用三种酸溶液浸提时,其钾素释放量仅占全钾量的1.53%~2.46%,通过层间交换反应释放的钾量占释放量的比例为88.4%~94.0%。四苯硼钠浸提时伊利石层间距扩大,产生次生过渡矿物,并形成富硅表层,但在伊利石表面无溶蚀特征;三种酸溶液浸提时伊利石结构无改变,但其结晶度降低,且表面有明显的溶蚀特征。因此,土壤矿物层间钾是作物可利用有效钾的主要来源,三种酸溶液浸提方法一方面低估了有效钾容量,另一方面提取了一部分不能为植物所利用的结构态钾,不适宜于用来评价伊利石及土壤有效钾库容量。     

羟基萘酚蓝在伪狂犬病病毒环介导等温扩增检测方法中的应用

伪狂犬病毒(Pseudorabies virus,PRV)传统诊断方法具有程序繁琐、周期长、成本高、特异性差等缺点,本实验建立了敏感、特异的PRV的环介导等温扩增(loop-mediated isothermal amplification,LAMP)检测方法,并在此基础上应用金属离子指示剂羟基萘酚蓝(hydroxy naphthol blue,HNB)进行反应结果判定.实验选取保守性较高的gB基因(glycoprotein B,糖蛋白gB)筛选引物,确定反应体系后,可在45 min内完成检测.LAMP方法特异性与PCR方法一致,敏感性是PCR方法的100倍,最低能够检测10个拷贝的目的基因.在HNB的应用试验中,发现LAMP反应体系中,HNB浓度为150 μmol/L时,阴阳性的颜色对比明显且反应的敏感性最高,可用于LAMP扩增产物的判断.临床样本的检测结果表明,PCR方法和LAMP方法的检出率一致.因此,本研究中所建立的LAMP方法是一种高度特异敏感的,可替代PCR方法的检测技术.     

Arbuscular Mycorrhizal Fungi Enhance Tolerance of Rosa multiflora cv. Burr to Bicarbonate in Irrigation Water

ABSTRACT

High bicarbonate (HCO₃ ^?) of irrigation water can be detrimental to plant growth in sustainable horticultural production systems. The ability of arbuscular mycorrhizal fungi (AMF), ZAC-19, (composed of Glomus albidum, Glomus claroideum, and Glomus diaphanum) to enhance tolerance to HCO₃ ^? was tested on Rosa multiflora cv. Burr. Arbuscular mycorrhizal colonized and non-inoculated (non-AMF) plants were treated with 0, 2.5, 5, and 10 mM HCO₃ ^?. Increasing HCO₃ ^? concentration and associated high pH and electrical conductivity (EC)—reduced plant growth, nutrient uptake, and acid phosphatase activity, while increasing alkaline phosphatase activity (ALP). Inoculation with AMF enhanced plant tolerance to HCO₃ ^?, as indicated by greater growth (leaf, stem, and total plant dry weight, leaf area and leaf area ratio), leaf elemental concentration [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), iron (Fe), zinc (Zn), aluminum (Al), boron (B)], leaf chlorophyll concentration, higher mycorrhizal inoculation effect, lower root Fe reductase activity, and generally lower soluble ALP activity. While AMF colonization was reduced by increasing HCO₃ ^? concentration, colonization still occurred at high HCO₃ ^? concentration. At 2.5 mM HCO₃ ^?, AMF plant growth was comparable to plants at 0 mM HCO₃ ^?, further indicating the beneficial effect of AMF for alleviation of HCO₃ ^? plant stress.     

产L-苯丙氨酸解氨酶菌种筛选

从土壤中筛选出1株具有L-苯丙氨酸解氨酶(L-Pheny la lan ine amm on la-lyase,PAL)较高酶活力的产生菌株——酵母菌SA 1。L-酪氨酸(L-T yr)为该菌株产PAL的最佳诱导物;利用反式肉桂酸转化L-苯丙氨酸(L-Phe)的最佳酶促反应条件为:2.0%反式肉桂酸,碳酸氢铵∶氨水(W∶V)=4∶4,pH 10.6,34°C,反应8 h,在转化体系中添加甘油对酶活力有较好的保护作用。     

Irrigation Module and Sowing Date Affect Seed Cotton Yield,Quality, Productivity Indices,and Economics of Cotton in North-western India

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. PSI_h (100 mm) recorded 23.2% higher seed cotton yield over PSI_n (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. PSI_h exhibited better NFP over PSI_n. 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.