施钾对高油玉米和普通玉米吸钾特性及子粒产量和品质的影响

采用田间试验研究钾肥用量对高油玉米和普通玉米吸钾特性及子粒品质和产量的影响。结果表明,两品种钾素吸收最大速率随施钾量的增加呈增加趋势,在施K2O.90150.kg/hm2范围内,通油1号的钾素吸收最大速率大于四密25。成熟期通油1号的吸钾总量明显高于四密25,但其子粒产量却低于四密25。玉米子粒的钾素绝大部分来源于开花后根系的吸收。通油1号开花后根系钾素吸收量和成熟期子粒钾素吸收总量明显高于四密25。高油玉米通油1号含有较高的脂肪酸和蛋白质含量,但淀粉含量较低。施钾在提高产量的同时,增加了子粒中脂肪和蛋白质及其组分含量,但减少了淀粉总量和支链淀粉含量。表明子粒中淀粉、蛋白质、脂肪和产量之间存在内在联系。     

氮肥用量对高淀粉玉米和普通玉米吸氮特性及产量和品质的影响

采用田间试验研究氮肥用量对高淀粉玉米(郑单21)和普通玉米(四密25)吸氮特性及子粒品质产量的影响。结果显示,与普通玉米相比,高淀粉玉米氮素最大吸收速率较大,出现日期早,成熟期吸氮总量高,但其子粒产量却较低。高淀粉玉米子粒中的氮素更多依赖于后期的根系吸收,而较少来源于前期营养体的氮素转移;其淀粉总量、支链淀粉含量较高,而直/支比值较低。在蛋白质及其组分含量上,郑单21含有较高的粗蛋白总量及清蛋白、球蛋白和谷蛋白含量,但醇溶蛋白含量较低;在脂肪酸及其组成上,虽然郑单21的脂肪酸总量较低,但不饱和脂肪酸比例较高。在各品质组分上,支链淀粉、醇溶蛋白、软脂酸、油酸和亚油酸含量对氮肥的反应与淀粉含量、粗蛋白含量和脂肪酸总量的变化趋势基本一致,均随施氮量的增加而增加,但过量施氮则其含量下降。施氮对直链淀粉含量、清蛋白、球蛋白和谷蛋白含量、硬脂酸、花生酸和亚麻酸无明显影响。     

施氮对高淀粉玉米和普通玉米子粒可溶性糖和淀粉积累的影响

采用田间试验、植株生理生化分析和电镜观察等方法，研究了不同氮肥用量对高淀粉玉米吉单535和普通玉米军单8号子粒糖分与淀粉形成的影响。结果表明，在施氮量N 0～200 kg/hm2之间，两品种玉米子粒淀粉含量随着施氮量的增加而增加，过量施氮则淀粉含量降低。灌浆期吉单535子粒蔗糖、果糖、葡萄糖含量高于军单8号，适量施氮使子粒灌浆期保持较高的蔗糖、果糖和葡萄糖含量，有利于淀粉合成。高淀粉玉米在成熟期淀粉粒充满了细胞，大小均匀，排列有序；普通玉米的淀粉粒则没有充满细胞，大小不一，排列混乱。适宜施氮下淀粉粒大小较为均匀，淀粉粒之间挤压轻微，而过量施氮下淀粉粒相互挤压成多面体状。     

氮素对不同类型玉米蛋白质及其组分和相关酶活性的影响

以普通玉米掖单22和高油含量玉米高油115为材料,测定了不同供氮水平下子粒蛋白质含量及其组分以及叶片和子粒中硝酸还原酶(NRase)、谷氨酰胺合成酶(GS)和谷氨酸脱氢酶(GDH)活性的品种差异。结果表明,玉米子粒蛋白质及其组分含量,均为高油115显著高于掖单22,其中醇溶蛋白和白蛋白含量增幅明显,且随施氮量的增加而提高。不同供氮条件下,两种类型玉米叶片中NRase、GS活性和子粒中GS、GDH活性的动态变化一致,NRase活性自灌浆初期至成熟期一直下降,GS、GDH活性呈单峰曲线,在授粉后20～30d达到高峰;增施氮肥有利于酶的活性维持较高水平。掖单22叶片中NRase活性高于高油115;叶片GS和子粒GDH活性显著低于高油115,这可能是其蛋白质含量较低的生理原因之一。     

氮肥用量对普通玉米产量和营养品质的影响

利用田间试验研究了施用氮肥对玉米黔兴2302产量和营养品质的影响。结果表明，施用氮肥不仅显著提高了子粒产量，增产9.59%~23.14%，且不同程度上增加了蛋白质、氨基酸、淀粉和脂肪酸的含量；但不改变直链淀粉和支链淀粉的比值，对玉米口感无不良影响。在玉米子粒中，蛋氨酸、苯丙氨酸、赖氨酸、天门冬氨酸、丝氨酸、谷氨酸、甘氨酸、组氨酸、精氨酸、亚麻酸含量比较稳定，主要受遗传基因的控制，难于因施肥而改变；其余营养成分，如清蛋白、球蛋白、醇溶蛋白、谷蛋白、苏氨酸、缬氨酸、异亮氨酸、亮氨酸、丙氨酸、酪氨酸、脯氨酸、直链和支链淀粉、油酸、亚油酸、棕榈酸和硬脂酸含量因施用氮肥而发生变化，它们的含量既受遗传基因的控制，也受施用氮肥的影响。综合考虑玉米的产量和品质，本试验条件下，黔兴2302玉米较为适宜的氮肥用量约为N 150 kg/hm2。     

不同氮效率油菜品种产量和品质对供氮水平的反应

为探明不同氮效率油菜产量和品质对供氮水平的反应动态,揭示油菜氮效率与品质的关系,本文采用砂培试验,研究了两种氮效率油菜品种在06、3、6、12、15 mmol/L 5种不同氮水平下（用N1N5表示）的氮效率、子粒产量和品质的变化。结果表明, 随着供氮水平的提高,油菜子粒产量、油分产量和蛋白质含量增加,氮效率和油分含量下降; 而子粒脂肪酸组成变化较小,所测定的7种脂肪酸中,芥酸和花生烯酸含量随着氮水平的增加略有下降,棕榈酸、硬脂酸、油酸、亚油酸和亚麻酸含量则没有明显的变化; 与氮低效品种相比,氮高效品种的子粒产量、芥酸和花生烯酸含量随供氮水平的变化幅度更大,油分含量下降幅度更小。所有氮水平下,氮高效品种的子粒产量、油分含量和油分产量均高于氮低效品种,亚油酸含量略高于而亚麻酸含量略低于氮低效品种,子粒蛋白质、棕榈酸、硬脂酸、油酸含量两品种没有差异。总之,提高氮水平有利于增加油分产量,氮高效品种的增加幅度大于氮低效品种,但对脂肪酸组成的影响较小。因此,氮高效品种不会因高效吸收利用氮素而降低油分含量或使油菜品质变劣。     

施氮和不施氮对玉米子粒品质性状的影响及QTL分析

本研究以玉米杂交种农大108的F2:4、F2:5家系为材料，构建了包含199个SSR标记，覆盖玉米10条染色体的遗传连锁图谱，图谱总长度2101.1 cM，平均间距为10.6 cM。在施氮（+N）和不施氮（-N）两种条件下对群体进行了鉴定，利用近红外反射光谱(NIRS)方法测定了群体子粒的蛋白质、淀粉、油分和赖氨酸含量。结果表明，在不施氮条件下子粒的蛋白质、脂肪和赖氨酸含量下降，而淀粉含量上升，但不同材料的变化幅度不同。采用复合区间作图法共检测到24个与玉米子粒品质性状相关的QTLs，其中施氮条件下13个，不施氮条件下11个，涉及21个不同位点的QTLs，分布在1，2，3，4，7，9染色体上，且集中在第3染色体上的QTLs有6个，第9染色体上的QTLs有7个，分别占测到总QTLs的28.57%和33.33%。单个QTL贡献率在8.05%~34.31%之间，其中，qPro1a是不施氮条件下与蛋白质含量相关的主效QTL，qOil3b是不施氮条件下与油分含量相关的主效QTL，贡献率分别达34.31%和17.66%。在21个不同的QTLs中，9个表现加性效应，8个表现部分显性。     

钾素营养对玉米生育后期干物质和养分积累与转运的影响

为揭示钾素营养与玉米产量形成的关系，研究了3个施钾水平（K2O　0、113和225 kg/hm2）对玉米生育后期植株不同器官干重及氮、磷、钾积累和转运的影响。结果显示，施钾能显著提高玉米产量。随着施钾量的增加，玉米生育后期干物质积累的最大速率和平均速率提高，最大速率出现时间提前。玉米干物质在各器官中的分配比例随生长发育中心的转移而变化。生育后期干物质和养分由营养体向子粒转运，其中干物质和氮、磷主要来源于穗部营养体的转运，而钾则主要来源于叶片的转运。子粒中氮、磷、钾的积累量分别占总积累量的50.3%～57.1%，59.6%～67.2%和14.0%～33.3%。施钾不但能增加子粒中干物质和氮、磷、钾养分的分配比例，而且还有助于提高干物质和氮、磷、钾养分向子粒转运的转运率。氮的转运率以K1处理最大，为45.7%；干物质、磷和钾的转运率以K2处理最大，分别为7.4%、62.6%和22.4%；子粒养分中54.5%～60.6%的氮，56.0%～85.8%的磷及52.4%～100.0%的钾可以依赖于营养体的转运。     

生长调节剂对玉米氮代谢的影响

采用田间小区试验,研究了植物生长调节剂不同配方对玉米光合特性、氮素代谢以及玉米子粒产量与蛋白质含量的影响。结果表明,调节剂不同配方处理能明显提高子粒灌浆期玉米功能叶叶绿素的含量和净光合速率,功能叶与茎秆中的全氮和蛋白氮的减少量,功能叶的硝酸还原酶、谷氨酰胺合成酶与转化酶活性及子粒谷氨酰胺合成酶与转化酶活性;灌浆中、后期玉米功能叶蛋白水解酶活性和玉米子粒产量、子粒蛋白质含量及蛋白质产量。在生长调节剂中,PGR4处理玉米子粒的蛋白氮含量比对照提高1.35.g/kg,子粒产量比对照增加9.5%,子粒蛋白质产量比对照增加19.6%;PGR3处理玉米子粒的蛋白氮含量比对照提高0.78.g/kg,子粒产量比对照增加11.4%,子粒蛋白质产量比对照增加17.4%,是较合理的配方。     

氮、磷营养对黄土高原旱地玉米产量、品质的影响机理研究

田间裂区试验研究了不同氮磷施用水平对旱地玉米子粒产量和品质的影响。结果表明，增施氮、磷肥，能增加子粒粗蛋白、粗脂肪、赖氨酸含量和子粒容重，降低粗淀粉的含量，提高玉米产量和水分利用效率，且氮肥效果优于磷肥。施用氮、磷肥能够增加土壤碱解氮、速效磷的浓度，有利于玉米根系对氮磷营养的吸收；在促进根系生长的同时，提高玉米的生物产量，增加植株茎秆、叶片对氮素、磷素的吸收、转化以及向穗轴、子粒的输送，显著提高子粒的灌浆强度，促进灌浆中后期子粒氮、磷的积累，增大粒重，改善子粒品质。     

尿素配施添加剂NAM对三江平原白浆土氮素转化和玉米产量的影响

通过田间小区试验,研究了尿素配施肥料添加剂NAM(由脲酶抑制剂和硝化抑制剂等成分组成)对三江平原白浆土氮素转化、玉米产量以及氮肥利用率的影响,以期为肥料添加剂NAM的进一步推广应用提供理论依据。研究结果表明,与常规施氮处理相比,等氮量配施NAM处理使土壤NH4+-N在较长时间内维持较高的水平,并显著提高了作物后期的土壤总有效氮供应水平,从而使作物吸氮量增加了6.8%,增产3.1%;减氮20%配施NAM处理维持了土壤NH4+-N总体供应水平和作物后期的土壤总有效氮供应,从而使作物吸氮量及产量与常规施氮处理保持相当;减氮40%配施NAM处理由于过多降低了施氮水平,致使在作物生长前期土壤供氮量明显不足,进而降低了作物吸氮量及产量。尿素配施NAM较单施尿素提高氮肥利用率4.9～8.0个百分点。在等氮和适当减氮条件下,肥料添加剂NAM适用于三江平原白浆土-玉米体系,有利于农业可持续发展。     

不同NPK配置对强筋小麦群体生物量与产量的效应研究

在关中川道灌区以强筋小麦陕253为材料,研究了不同NPK配置对其不同生育期生物产量、群体数量和产量的效应,结果表明提高施肥量可显著增加生物产量、群体数量及产量,处理平均值分别比常规处理增加11.9%~43.6%、4.1%~17.4%和8.3%,其最佳N、P、K配置依次为N135kg hm-2,P2O5和K2O各120kg hm-2、N135kg hm-2,P2O5225kghm-2,K2O120kg hm-2和N225kg hm-2,P2O5和K2O各120kg hm-2。在目前常规投肥水平下适度增加钾肥有利于生物产量的显著提高,增加磷肥和钾肥有利于群体数量的提高,增施氮钾肥有显著的增产效果。产量的最佳NPK配比较常规处理增产19.1%,其增加养分的平均产量4.44 kg kg-1,比各处理平均养分产量高1.6倍。     

花后灌水对高油玉米碳氮运转的影响

在大田条件下,研究了花后灌水对高油玉米碳氮积累和运转的影响。结果表明，花后灌水降低了高油玉米叶、茎、鞘等营养器官贮藏物质、氮紊的再运转量和再运转率以及贮藏物质、氮素的总运转量和总运转率，花后籽粒吸收氮素量和光合同化物输入籽粒量表现为不灌水〉灌一水〉灌三水。花后籽粒吸收氮素量对籽粒氨素的贡献率则与营养器官贮藏氮素转移的贡献率相反，即灌三水处理值表现最高，花后籽粒吸收氮素量和光合同化物对籽粒的贡献率远大于营养器官贮藏氮素和同化物转移的贡献率。高油玉米籽粒、蛋白质、淀粉和油产量以花后灌一水最高，灌三水时降低；随灌水次数增加籽粒油分含量增加，蛋白质含量下降。     

NITROGEN,PHOSPHORUS, AND POTASSIUM NUTRIENT EFFECTS ON GRAIN FILLING AND YIELD OF HIGH-YIELDING SUMMER CORN

A three-site-year field experiment was conducted to determine nitrogen (N), phosphorus (P), and potassium (K) fertilizer effects on grain filling dynamics and yield formation of high-yielding summer corn (Zea mays L.) in a wheat (Triticum aestivum L.)-corn double crop cropping system. Application of combined NPK fertilizers resulted in the greatest grain yield, largest grain number and grain weight when compared with the treatments receiving N, NP, or NK. Grain filling rate and duration, grain volume, and grain yield increased with NPK rates; however, doubling the rate of 180 kg N ha^?1, 40 kg P ha^?1, and 75 kg K ha^?1 fertilizer only led to minimal increases in grain filling rate (0.8%), grain filling duration (1.6%), grain volume (1.3%) and grain yield (0.4%). Our results suggested that for the high-yielding summer corn, a combined NPK fertilization is required to enhance grain filling and yield, and that under well-fertilized circumstances, limited increases in both grain filling and sink capacity might be the main factor restricting further yield improvement.     

硫肥对棉花蕾铃脱落及产量的影响

本文就硫素与棉花蕾铃脱落和产量的关系进行了研究。试验结果表明,在传统施肥量330kg N/hm2,60kg P/hm2情况下,棉花蕾铃脱落率达70.3%;在增加氮磷肥施用量并补施硫酸钾情况下,棉花蕾铃脱落率为68.5%,说明硫酸钾有效降低了棉花的蕾铃脱落率。在传统施肥量基础上施用硫磺30.0kg/hm2对棉花的蕾铃脱落没有影响,但是增加了棉花单株结铃数、提高了产量。与不施硫相比,施硫使棉花单株结铃数增加14.7%,产量增加了15.7%。上述结果说明,在新疆高产棉田中使用单质硫肥能够进一步增加棉花产量。     

Plant density,distribution, and fertilizer effects on yield and quality of irrigated corn silage

Abstract

Grain deficits frequently occur in the Southeastern Atlantic Coastal Plain because erratic rainfall patterns and soil properties often limit corn (Zea mays L.) yields, however, harvesting corn for silage may enable farmers to produce a second grain crop during the same calendar year. Effects of row spacing, plant population, and fertilizer program on yield, quality, and mineral concentrations of corn silage grown with irrigation on Typic Paleudult soils were therefore investigated. Two plant population treatments which averaged 7.0 and 10.1 plants m^‐2 were evaluated with two fertilizer programs that differed in N, N and K, and N, P, and K in 1980, 1981, and 1982, respectively. Each plant density by fertilizer combination was evaluated in single rows spaced 96 cm apart and in twin rows which approximately doubled the intrarow plant spacing. Plot size for the 2×2×2 factorial experiment ranged from 30 to 44 m². Yield, quality, and mineral concentrations of corn silage grown in single rows spaced 96 or 75 cm apart and twin rows were also evaluated in large (185 m²) plots under center pivot irrigation during 1981 and 1982.

Dry matter yields of 22 to 26 Mg ha^‐1 were achieved with plant densities of 6.7 to 13.5 plants m^‐2 at both experimental sites. Highest silage yields were produced with stand densities of 9 m or more planted in single 75 cm or twin rows, but yield differences were statistically significant at P(0.05) in only two of five site years. Increasing total N‐P‐K application beyond 200–30–167 kg ha”; increased crude protein slightly in 1980 and significantly in 1981 and 1982. Concentrations of Mn and Zn in silage were increased by higher fertilization, presumably because nitrification reduced surface soil pH and increased their availability. Dry matter yield, fiber, energy, and other mineral nutrients were not significantly influenced by fertilizer program. These experiments identified management practices for the Atlantic Coastal Plain which resulted in corn silage yields equal to those produced in the cooler mountain region of Georgia and that exceeded current average production in South Carolina by approximately 40% without reducing apparent feed quality.     

Corn Hybrid Response to Starter Fertilizer Combinations

ABSTRACT

Research has shown that some corn (Zea mays L.) hybrids grown under reduced tillage conditions respond to starter fertilizer containing nitrogen (N) and phosphorus (P), while others do not. This research studied variability of responsiveness among corn hybrids to starter fertilizer containing a more complete complement of nutrients. The experiment was conducted from 1996 to 1998 on a producer's field near Scandia, KS, on a Carr sandy-loam soil (coarse-loamy, mixed, superactive calcareous, mesic Typic Udifluvents). The response of four corn hybrids (Pioneer 3563, Pioneer 3346, DeKalb 591, and DeKalb 646) to starter fertilizer combinations containing N, P, potassium (K), sulfur (S), and zinc (Zn) was evaluated. In all three years of the experiment, starter fertilizer containing N and P consistently increased grain yield, reduced the number of thermal units needed from emergence to maturity, decreased grain-moisture content at harvest, and increased total P uptake (grain plus stover at maturity) of Pioneer 3346 and DeKalb 591, but had no effect on Pioneer 3563 and DeKalb 646. Addition of S to the starter mix produced additional yield increases for Pioneer 3346 and DeKalb 591, whereas addition of K and Zn to the starter did not show any additional yield benefit for these two hybrids. Grain yield of Pioneer 3563 and DeKalb 646 was not improved by starter fertilizer, regardless of the elemental composition. When no starter fertilizer was applied, early-season root development was greater in Pioneer 3563 and DeKalb 646 than in the other two hybrids. However, the addition of starter fertilizer increased numbers of roots and depth of rooting in Pioneer 3346 and DeKalb 591 but had no effect on Pioneer 3563 and DeKalb 636. Results showed starter fertilizer benefited grain yield for two hybrids. Grain yield of the other two hybrids, however, was not influenced by starter, regardless of which nutrients were supplied. This response may be attributed to differences in root-growth characteristics of the hybrids. The two responsive hybrids did, however, yield an average of 0.75 mg ha^?1 greater than the two non-responsive hybrids. This result indicates it is unlikely that all of the yield loss from not using a starter can be avoided by hybrid selection.     

氨基酸复合肥对盐碱土理化性状的改良效果

为了明确氨基酸复合肥对盐碱地改良及燕麦增产效果,探究连续2年在大田试验条件下施用A3(2250 kg/hm²)、A2(1500 kg/hm²)、A1(750 kg/hm²)和CK(0 kg/hm²)4个氨基酸复合肥对盐碱地土壤理化性状及产量的影响。结果表明,盐碱地施用氨基酸复合肥后,0~40 cm土层直径>0.25 mm土壤团聚体含量提高了0.17%~9.08%;土壤质量含水率随施肥量的增加而增加,在燕麦拔节期效果最为显著,较对照提高12.34%。0~40 cm土层,土壤pH由8.84降为8.03,全盐含量由9.16 g/kg降为8.30 g/kg;土壤有机质、碱解氮、有效磷、速效钾的含量分别增加12.22%~27.36%、1.16%~9.50%、7.18%~39.66%和7.83%~35.56%。燕麦的籽粒与鲜、干草产量增加显著,增产49.38%~65.16%。以施用2250 kg/hm²氨基酸复合肥对改善盐碱地土壤理化性状与增产效果最明显。