氮磷钾配合对棉铃经济性状空间分布的影响

试验结果表明：氮、磷、钾配合能显著促进棉株地上部、地下部干物质的累积,但根冠比有所降低;ＮＰＫ,ＮＰ,ＮＫ 配合有利于单株成铃率的提高,且成铃空间分布均匀;而棉铃性状表现为铃重、衣分、衣指、子指、单铃种籽数增加,不孕籽数减少,纤维长度变化不大;另外,不同的氮、磷、钾配合形式对棉铃各性状空间分布的影响趋势基本一致,影响程度是ＮＰＫ＞ ＮＰ＞ ＮＫ＞ ＰＫ．     

Enrichment of C20-22 Polyunsaturated Fatty Acids from Refined Liver Oil of Leafscale Gulper Shark,Centrophorus squamosus

The C_20-22 polyunsaturated fatty acids (C_20-22 PUFAs), mainly eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3), were concentrated from the refined liver oil of deep sea leafscale gulper shark, Centrophorus squamosus, by sequential processes of winterization, urea complexation, and argentation chromatography. Winterization at 4°C using acetonitrile as solvent showed significant reduction of the total saturated fatty acid content (12%) with a concomitant increase of polyunsaturated fatty acids (36.3%). The urea complexation process significantly enriched the total polyunsaturated fatty acids (49.5%), with a reduction in saturated fatty acids (83.9%). Silica gel based argentation chromatography further concentrated the esters of C_20-22 PUFA (>99 percent purity). Nuclear Magnetic Resonance spectroscopy was used as a chemical fingerprinting tool to study the enrichment of C_20-22 PUFAs at various stages of the purification process. An increase in the proton signal intensity at the olefinic region (at δ 4–6) and a decrease in the aliphatic signals (at δ 0.5–2) showed that the process successfully enriched the C_20-22 PUFAs.

Abbreviations: PUFA, polyunsaturated fatty acid; EPA, eicosapentaenoic acid; DHA, docosahexaenoic acid; FAME, fatty acid methyl esters; SFA, saturated fatty acid; MUFA, monounsaturated fatty acid; NMR, nuclear magnetic resonance; GCMS, gas chromatography mass spectrometry; FFA, free fatty acid.     

包膜尿素在盐碱土壤中氮素转化及其对玉米增产效应的研究

为探究包膜尿素一次性基施提高玉米氮素利用效率及增产机制。采用田间小区试验,比较施用不同材料包膜尿素和施用普通尿素对土壤氮素转化特征及玉米增产效应的差异。结果表明,与施用普通尿素相比,包膜尿素在玉米生长发育前期可抑制土壤中的脲酶活性,处理3、处理4、处理5对土壤脲酶抑制率分别达到27.06%、28.36%和39.50%;施用包膜尿素还可以延缓氮肥在土壤中的释放进程,保证在玉米生长后期,有充足的氮素释放。在玉米抽穗期,处理3、处理4、处理5的土壤碱解氮含量分别比对照(施用普通尿素)高出40.33%、66.64%和53.89%,同时施用缓释包膜尿素还可显著提高玉米籽粒产量。处理4(2#包膜尿素)效果最佳,比普通尿素处理增产26.87%,氮素偏生产力、氮农学效率和氮素利用率分别比对照增加13.13 kg grain/kgN、6.76 kg grain/kgN和10.33%。     

两种包膜尿素的氮释放特性及对高羊茅生长的影响

采用水浸泡法对2种包膜尿素(CU-1和CU-2)的初期溶出率和微分溶出率进行测定。2种包膜尿素的初期溶出率分别为9.5%和1.36%,符合国际上公认的缓/控释肥的初期溶出率小于15%的指标,而微分溶出率分别为2.48%和1.72%,也符合国际上公认的缓/控释肥的微分溶出率(0.25%~2.5%)的指标。通过盆栽试验研究了普通尿素(S1)、包膜尿素(H1和H2)以及二者配比(F1、F2、F3和F4)对高羊茅建植期生长的影响。结果表明:单一施用CU-2处理以及CU-2配施50%普通尿素处理明显促进了高羊茅地上部与地下部生物量的积累,促进了高羊茅对氮的吸收,尤其是生长后期,叶片中氮含量显著高于尿素与空白处理。另外,包膜尿素的应用减小了草坪生长速率的波动。     

保水利与养分交互作用对茄子幼苗生长的影响

研究了不同保水剂浓度与不同的全营养液肥浓度的交互务件下对茄子育苗生长的影响.结果表明:基质持水量随着保水剂浓度的增加而增加,但随养分供应浓度的增加,基质持水量并未随着保水剂浓度的增加而呈直线上升.基质EC值随养分浓度增加而极显著增加(P=0.01),随保水剂浓度增加而显著下降(P=0.05).基质PH值随着养分浓度的变化范围较小(P＜0.05),随着保水剂浓度的变化而发生极显著变化(P=0.01),表现为随着保水剂浓度的增加,基质pH值增加.通过对茄子幼苗的形态指标测定,表明在每升基质中加入2 g全营养肥,茄子幼苗生长较为茁壮;保水剂浓度在每升基质中加入2 g较为适宜茄子幼苗生长.在养分浓度和保水剂浓度适中的条件下,两者的交互作用可提高茄子幼苗的根系活力和叶片的叶绿素含量.综合各因素认为,A2B2处理为最优处理,即全营养肥2 g/L,保水剂浓度2 g/L时,较适合茄子幼苗生长.     

Mitigation of salt stress on tomato crop by using foliar spraying or fertigation of various products

Abstract

Among major constraints to crop production, salt stress affects the morphological structure and yield in crop plants. Nano-fertilizers, have made their hierarchy to supplement the traditional fertilizers in mitigating the effect of abiotic stress due to their slow release and efficiency. Three products were tested namely lithovit®-standard(LITHO), monopotassium-phosphate(MKP:0-52-34), and aspirin(ASP) on salt-stressed tomato crop. These products were applied through foliar spraying (foliar) or fertigation (ferti) on tomato plants irrigated with 4 saline solutions (4, 6, 8 and 10dS/m). Control plants were subjected to five salinity levels (0, 4, 6, 8 and 10dS/m) without any treatments. Results showed that increasing in salinity levels adversely affected all parameters in the control plants. The ameliorating effect of MKP-ferti was prominent in plant height, stem diameter, number of fruits, fruit weight and yield/plant at 4 and 6S/m. Whereas, the effect of salinity was mitigated by LITHO-foliar regarding flowers number and total chlorophyll content at all salinity level. Leaf N, P and K contents were accumulated higher when MKP-ferti was used whereas, Ca²⁺ and Mg²⁺ contents were accumulated higher in the plants treated with LITHO-foliar. The cellular leakage of electrolyte was reduced at 4, 6 and 10dS/m with MKP-ferti and at 8dS/m with LITHO-foliar application. Among the two methods of application, foliar spraying of LITHO and ASP, and fertigation of MKP improved plant performance more than their complementary methods of application. The better performance of MKP necessitates the use of phosphorous and potassium-based nano-fertilizers. It can reduce the production cost of vegetables using conventional fertilizers.     

微喷灌水肥一体化下磷钾肥减量分期施用对小麦产量和养分利用的影响

为探究微喷灌水肥一体化条件下小麦氮磷钾肥的合理用量及施用方式,以小麦品种良星99为试验材料,在磷钾肥减量30%和常规施肥量条件下各设置3种施肥方式,以传统大水漫灌撒施肥料的方式及用量为对照(CK),研究磷钾肥减施及施用方式对产量及养分利用的影响。结果表明,常规施肥(CK)相比,微喷灌水肥一体化磷钾肥减施30%(氮肥70%底施+30%拔节期追施、钾肥全部底施、磷肥50%底施+50%拔节期追施)条件下产量提高11.33%,成熟期植株氮、磷、钾积累量分别提高21.86%、10.02%和10.23%。与传统栽培模式及微喷灌常量施肥相比,利用微喷灌水肥一体化技术生育期灌水3次(越冬水+拔节水+灌浆水),灌水量1 500 m³·hm^-2,磷钾肥减施30%条件下,磷肥50%底施+50%拔节期追施能够提高小麦产量、成熟期植株氮磷钾积累量、偏生产力及产投比。本研究结果为山西省南部小麦节水节肥稳产高效栽培技术提供了理论依据。     

钵苗摆栽籼粳杂交稻和常规粳稻丰产优质适宜施氮量分析

研究钵苗摆栽下籼粳杂交稻、常规粳稻丰产优质施氮量及综合效益,提出安徽沿江地区钵苗摆栽下适宜粳稻类型及施氮量。于2016—2017年连续2 a开展大田试验,以当地主栽籼粳杂交稻甬优1540和常规粳稻镇稻18为供试品种,设置0、195、255、315、375 kg/hm~2共5个氮肥水平(分别用N0、N195、N255、N315、N375表示),研究不同施氮水平对钵苗摆栽下不同类型粳稻产量、品质、相关农艺性状及经济效益的影响。结果表明,籼粳杂交稻甬优15402a均在N315处理下产量最高,达到10.30～11.55t/hm~2。常规粳稻镇稻18各施氮处理下水稻产量无显著差异,产量为7.43～8.91 t/hm~2。增施氮肥,不同程度增加了2个品种的糙米率、精米率和蛋白质含量,提高了加工品质和营养品质,但垩白率和垩白度整体有所提高,直链淀粉含量增高,不利于外观品质和食味的改善。甬优1540在N315处理下的整精米率与N375无差异,且在N315处理下的垩白度与N195无显著差异。另外,镇稻18在N195处理下的整精米率、蛋白质含量、垩白度和直链淀粉含量与其他氮肥处理无显著差异。钵苗摆栽下籼粳杂交稻丰产优质施氮量为315kg/hm~2,常规粳稻为195 kg/hm~2。在适氮水平下,钵苗摆栽甬优1540较镇稻18提高水稻产量22.9%～23.2%,整精米率2.15%～4.50%,蛋白质含量30.44%～37.41%,经济效益51.07%～53.33%,同时降低垩白度9.52%～13.73%。总的来说,在适宜氮肥水平下,钵苗摆栽下籼粳杂交稻较常规粳稻提高了水稻产量、品质和经济效益。     

秋覆膜对辽西春玉米水肥利用效率和产量的影响

为了探明旱地秋覆膜对春玉米水分和氮肥利用效率的影响,2013—2015年在国家农业环境阜新观测实验站设置了秋覆膜(秋季收获后开始覆膜,AM)、春覆膜(传统生育期覆膜,SM)和不覆膜(NM)3个处理,利用田间观测结合15N同位素示踪的方法,分析秋覆膜栽培春玉米的水分与氮肥利用特征。结果表明,在连续2个较干旱的年份,AM促进了玉米干物质积累,2a的玉米籽粒产量分别较SM提高了19%和11%,较NM提高了14%和75%,但玉米生物产量与SM无显著差异(P0.05);AM在休闲期减少了水分消耗,在播种期土体蓄水量较SM和NM平均多35 mm,并在玉米生育期耗水量较SM和NM多,主要体现在玉米的抽雄期和灌浆期作物耗水量的显著增加(P0.05);在2014年,3个处理的玉米籽粒产量和生物产量水分利用效率无显著差异(P0.05);在2015年,AM与SM的玉米籽粒产量和生物产量水分利用效率无显著差异(P0.05),但均显著高于NM(P0.05),较NM平均提高了60%和65%;AM减少了氮肥损失,同时也较SM减少了土壤中氮肥的残留,显著提高了当季和翌年氮肥利用效率(P0.05),2a累计氮肥利用效率达到了50.5%,高于SM和NM,但AM在当季0～100 cm土层中残留的肥料氮显著高于NM(P0.05)。综合分析认为,在较干旱的年型下,旱地秋覆膜是辽宁西部半干旱区提高春玉米产量和水肥利用效率的一项有效技术措施,如进行氮肥优化施用,可进一步提升该技术在区域农业发展的应用价值。     

不同粒径生物炭包膜尿素缓释肥性能及缓释效果

为探究生物炭粉包膜处理对尿素缓释效果的影响,该研究以不同粒径稻壳生物炭粉为包膜材料,对尿素颗粒进行不同层数包膜处理,分别制备了3种生物炭包膜尿素缓释肥C_1(0.15 mm生物炭粉包膜)、C_2(内层0.15 mm,外层0.25 mm生物炭粉包膜)和C_3(内层0.15 mm,中层0.25 mm,外层0.425 mm生物炭粉包膜),并对生物炭包膜尿素缓释肥性能及缓释效果进行了分析研究。研究结果表明3种生物炭包膜缓释肥粒径主要分布在2.90～4.80 mm,随着包膜层数的增加,包膜缓释肥粒径随之增大,C_2和C_3粒径显著高于C_1(P0.05)。C_1、C_2和C_3的抗压强度为20.40～48.00 N,满足工业生产需求。与C_1和C_2相比,C_3颗粒表面较光滑,切面具有致密且孔隙结构丰富的层状结构,吸水倍率最小(1.69),耐水性也显著优于C_1与C_2(P0.05),氮元素缓释效果优于C_1与C_2。综上可以看出,3层包膜尿素缓释肥膜壳强度高于单层和双层包膜尿素缓释肥,通过控制不同膜层生物炭的孔隙结构和孔径,减缓水分的渗入及养分的流出过程,缓释效果突出,为生物炭包膜缓释肥的开发应用提供一个新技术路径。