大麦籽粒产量和氮积累的农艺因素效应

本试验研究了密度及氮肥运筹对大麦籽粒产量和氮积累的影响。结果表明，在本地区以基本苗为１７２万／ｈｍ＾２的群体籽粒产量最高，增加壮蘖肥和穗肥比例可明显提高植株器官氮含量和籽粒产量。明确了生产上宜采用的基本苗密度和氮肥运筹比例。     

大麦种植密度和氮肥用量对籽粒产量的影响

分析了大麦甘啤3号种植密度和氮肥用量对籽粒产量的影响，并找出最佳栽培措施技术，试验表明：本地区确定甘啤3号的较合理种植密度(播种量)在16．32kg／667m^2左右，较合理的氮肥用量在15kg／667m^2左右。     

大麦种植密度和氮肥用量对籽粒产量的影响

分析了大麦甘啤 3号种植密度和氮肥用量对籽粒产量的影响 ,并找出最佳栽培措施技术 ,试验表明 :本地区确定甘啤 3号的较合理种植密度 (播种量 )在 16 32kg/6 6 7m2 左右 ,较合理的氮肥用量在 15kg/6 6 7m2 左右。     

高产大麦的大量形成和养分积累特点研究

研究了每公顷单产５２５０ｋｇ以上的大麦群体产量形成和养分积累特点。结果表明,在适宜的基本苗下,争取高成穗数和粒重或争取高成穗率和实粒数都能取得高产;过早播种将导致年前生长过旺,年后生长发育受抑制,群体干物质和养分积累减缓;高产大麦的养分积累一直持续至成熟期,齐穗至成熟期有持高养分积累量;提高穗肥的施用比例是大麦高产的重要措施。     

大麦主要农艺性状与产量的灰色关联分析

运用灰色系统理论,对江苏省10个大麦新品种(系)的生育期、株高、基本苗、穗数、每穗粒数、千粒重6个主要农艺性状与产量进行灰色关联度分析,结果表明各性状与产量的关联度依次为:穗数>千粒重>株高>基本苗>每穗粒数>生育期.     

大麦新品种闽诱3号的麦草和籽粒产量及其主要营养含量分析

大麦新品种闽诱３号，经连续两年区试和多年多点大面积试种，比福建省主栽品种莆大麦４号增产５．８～１９．４％（籽粒），麦草（幼嫩）产量为莆大麦４号的１６３．９％，籽粒中的蛋白质和氨基酸含量分别比莆大麦４号高２．３１和２．４５个百分点，麦草中的蛋白质和氨基酸含量分别高６．７５和４．８７个百分点，新鲜的麦苗汁液中还含有大量的矿物质，维生素和ＳＯＤ。     

不同施肥方法对大麦苗产量和品质的影响

试验在适宜的复合肥施用量研究的基础上,进一步探讨等量复合肥(62.5 kg/667 m2)不同时期分配比例对麦苗产量及品质的影响。结果表明,等量复合肥做基肥一次性施用的麦苗产量最高,综合营养品质也较好,叶绿素和可溶性蛋白质含量均明显提高。随着基肥和前期追肥比例下降,麦苗产量和品质均呈现下降趋势。试验认为,以收获嫩麦苗为目的的大麦生产,由于生长期短和多次割青,前期养分需要量明显加大,栽培上应高度重视增加基肥和前期施肥比例。     

栽培措施对直播油菜冬前生物学性状及产量的影响

采用三元二次回归旋转组合设计,研究油菜直播栽培方式下,栽培密度、施氮量、施磷量与冬前植株各形态、生理指标及产量之间的关系,获得了产量高于3 000kg/hm2的优化农艺措施方案,以及冬前各形态、生理指标与产量之间的关系.     

Effects of plant density and nitrogen and potassium fertilization on cotton yield and uptake of major nutrients in two fields with varying fertility

As the most important cultural practices for cotton production, the single effects of plant density and [nitrogen (N) and potassium (K)] fertilization on yield and yield components are well documented but their combined effects on Bt cotton are poorly understood. Using a split–split plot design with four replications, we conducted a two-year field experiment in two fields, one with lower fertility and the other with higher fertility, in the Yellow River Valley of China. The aim was to evaluate both the individual and combined effects of plant density and nitrogen and potassium fertilization on yield, yield components and uptake of major nutrients. The main plots were assigned to plant density (4.5 and 7.5 plants/m²), while nitrogen (0 and 240 kg N/ha) and potassium fertilization (0 and 150 kg K/ha) were assigned to the sub- and sub–subplots. Lint yield was improved with high plant density (7.5 plants/m²) in the lower fertility field, particularly without N and K application, but not in the higher fertility field. Nitrogen or K application also increased lint yield, and a combination of high plant density, N and K application further improved lint yield in the lower fertility field, while only K application increased lint yield in the higher fertility field. Lint percentage was not affected by any of the variables studied. Thus, the yield increase due to plant density, fertilization or their combinations was attributed to increases in boll number or boll weight. The ratio of seed cotton to stalk (RSS) was linearly correlated with harvest index, and thus can be a simple indicator of dry matter allocation to reproductive structures. Increased yield due to plant density and fertilization was mainly attributed to the enhanced biological yield in the lower fertility field, while the yield increase due to K fertilization was mainly due to increased RSS in the higher fertility field. The plants used approximately equal N and P to produce 100 kg lint in both fields, but the uptake of K to produce 100 kg lint in the higher fertility field was about 21% more than that in the lower fertility field. Ratios of N:P:K were 1:0.159:0.604 in the lower fertility field and 1:0.159:0.734 in higher fertility field. This study suggests that K fertilization was extremely important for maintaining high yield, although luxury consumption occurred in the higher fertility field; N was applied more than required in the highly fertile field, and increased plant density would be beneficial to cotton yield in the lower fertility field.     

密度和施氮量对沿海滩涂中度盐碱地蓖麻产量和氮素吸收的影响

以淄蓖5号和云蓖泰国202为材料,研究沿海中度盐碱地不同种植密度和施氮量对蓖麻产量和氮素吸收利用的影响.结果表明,淄蓖5号在种植密度13000株·hm-2、施氮量120kg·hm-2条件下获得的产量最高,云蓖泰国202的适宜密度为16 000株·hm-2、施氮量为120kg· hm-2.两个品种苗期对氮的吸收速率均缓慢,吸收量较低,蕾期吸收速率和吸收量逐渐增加,开花期达到高峰.高产条件下,每生产l00kg的蓖麻籽淄蓖5号需氮9.93～l0.33kg,云蓖泰国202需氮8.25～l0.12kg.在苗期、蕾期、开花期、花果期和灌浆成熟期,淄蓖5号分别保持2%、15%、50%、15%和20%左右的氮吸收百分率有利于高产;云蓖泰国202分别保持1%、10%、45%、12%和30%左右的氮吸收百分率有利于高产.     

氮肥用量对油菜产量及氮素利用效率的影响

通过大田试验研究了氮肥用量对油菜产量、养分含量、养分累积量及氮肥利用效率的影响。结果表明,与不施氮相比,施氮肥75、150和225kg/hm2平均分别增产41.9%、70.3%和66.2%,籽粒含氮量分别提高9.1%、14.2%和13.1%,植株地上部氮素总累积量分别增加59.6%、111.6%和108.0%。施氮促进油菜生长发育,显著提高油菜对氮素的吸收、累积和籽粒需氮量,但氮肥农学利用率、偏生产力和表观利用率均随氮肥用量的增加显著下降。氮肥用量在150kg/hm2时,能较好地协调油菜较高产量水平与合理氮肥利用率的统一。     

施氮量对花生叶片蔗糖代谢及产量的影响

以花生品种花育17为材料，在大田高产栽培条件下，研究了不同施氮量对花生叶片蔗糖代谢及产量的影响。结果表明：施氮对花生叶片蔗糖合成具有调节作用，适量施氮有利于提高磷酸蔗糖合成酶和蔗糖合成酶活性，促进叶片蔗糖合成；在一定施氮量范围内，增加氮肥用量，能提高花生产量各构成因素的水平，从而提高荚果产量。但过量施氮，产量各构成因素水平下降，经济系数显著降低，荚果产量降低。由本文得知：花生高产的最适施氮量为157.8 kg/hm2左右。     

Effect of nitrogen and phosphorus application on soil nitrogen morphological characteristics and grain yield of oil flax

In order to identify effects of nitrogen (N) and phosphorus (P) on soil nitrogen morphological characteristics and grain yield of oil flax, a two-factor experiment was conducted in a randomized complete block design in typical semi-arid and hilly-gully area of Loess Plateau with 3 replicates in 2013 and 2014. Two levels of N application included 150 ​kg/hm² (N₂) and 75 ​kg/hm² (N₁). P application included 150 ​kg P₂O₅/hm² (P₂) and 75 ​kg P₂O₅/hm² (P₁). Temporal and spatial variation of soil nitrate nitrogen (NO₃⁻-N) and ammonium nitrogen (NH₄⁺-N) contents in 0–60 ​cm soil layer, and relationship between soil NO₃⁻-N accumulation (SNA) and grain yield of oil flax were analyzed. Results showed that SNA increased with evaluated N application rate in different soil layers (0–20 ​cm, 20–40 ​cm and 40–60 ​cm). With the increased P application, SNA increased at N₁ level but decreased at N₂ level. SNA under N₂P₁ treatment increased by 73.33% in 2013 and 74.97% in 2014 respectively, compared with control treatment (CK) at maturity stage. Grain yield of oil flax also increased by 44.27% in 2013 and 56.55% in 2014, compared with CK under the same treatment. Correlation analysis showed that SNA in different soil layers were respectively positively correlated with grain yield. In conclusion, this research suggested that the optimal fertilizer application rate was 150 ​kg ​N/hm² and 75 ​kg P₂O₅/hm² in the Northwest of China.     

Determinants of barley grain yield in a wide range of Mediterranean environments

Barley grain yield in rainfed Mediterranean regions can be largely influenced by terminal drought events. In this study the ecophysiological performance of the ‘Nure’ (winter) × ‘Tremois’ (spring) barley mapping population (118 Doubled Haploids, DHs) was evaluated in a multi-environment trial of eighteen site–year combinations across the Mediterranean Basin during two consecutive harvest years (2004 and 2005). Mean grain yield of sites ranged from 0.07 to 5.43 t ha⁻¹, clearly dependent upon both the total water input (rainfall plus irrigation) and the water stress index (WSI) accumulated during the growing season. All DHs were characterized for possessing molecular marker alleles tagging four genes that regulate barley cycle, i.e. Vrn-H1, Vrn-H2, Ppd-H2 and Eam6. Grain yield differences were initially interpreted in terms of mean differences between genotypes (G), environments (E), and for each combination of genotype and environment (GE) through a “full interaction” ANOVA model. Variance components estimates clearly showed the greater importance of GE over G, although both were much lower than E. Alternative linear and bilinear models of increasing complexity were used to describe GE. A linear model fitting allelic variation at the four genes explained genotype main effect and genotype × environment interaction much better than growth habit itself. Adaptation was primarily driven by the allelic constitution at three out of the four segregating major genes, i.e. Vrn-H1, Ppd-H2 and Eam6. In fact, the three genes together explained 47.2% of G and 26.3% of GE sum of squares. Grain yield performance was more determined by the number of grains per unit area than by the grain weight (phenotypic correlation across all genotypic values: r = 0.948 and 0.559, respectively). The inter-relationships among a series of characters defining grain yield and its components were also explored as a function of the length of the different barley developmental phases, i.e. vegetative, reproductive, and grain filling stages. In most environments, the best performing (adapted) genotypes were those with faster development until early occurrence of anthesis. This confirmed the crucial role of the period defining the number of grains per unit area in grain yield determination under Mediterranean environments.     

氮素水平对油菜根茎叶氮素输出 及角果中氮素积累的影响

通过测定不同施N条件下油菜各器官的N素含量,研究了油菜后期根、茎枝、叶片等营养器官中N素的 输出和角果中N素的积累。其主要结果如下: (1)根、茎枝、叶片中N素积累量的变化呈先增后减的趋势,一般在 开花期前后达最大值;角果中N素总量随角果的生长逐渐增加。增施N肥明显增加各器官的N素积累量,推迟最 大值出现的时间。(2)根系、茎枝、叶片中的N素向外输出的比例随施N量的增加而下降,分别占其最大值的20% ～35%、35%～65%、55%～70%。(3)角果中的N素有30%左右来自叶片中N素的再利用,受施肥量的变化影响 较小; 35% ～10%来自茎枝的N素的再利用,随施N量的增加而减少;来自根系中N素的再利用不足5%;来自开 花后从土壤中吸收的N素约为30% ～60% ,随施N量的增加而增加。     

Perspective on oil flax yield and dry biomass with reduced nitrogen supply

Field experiment was arranged in a randomized complete block design to determine effects of nitrogen (N) application levels (J0: 150 ​kg/hm², J1: 120 ​kg/hm², J2: 90 ​kg/hm², J3: 60 ​kg/hm²) on regulating dry biomass accumulation, allocation and translocation, and grain yield of oil flax during 2018 cropping season. Significant promotion was observed in dry matter during accumulation stage of oil flax, when N rate was reduced by 40% (from 150 to 90 ​kg/hm²). Under J2 treatment, translocation of dry matter from vegetative organs to pod increased by 38.46% and 61.54% respectively, when compared with J1 and J0 treatment. Dry matter distribution proportion of pod at maturity increased 4.47%–7.61%, contribution rate of leaf to grain upgraded 5.09%–8.77%, and number of effective pods and grains per pod increased by 27.16%–45.38% and 6.49%–26.59% respectively compared to other treatments. As a result, seed yield of oil flax under J2 treatment was 2.23%–18.21% higher than those of other treatments. Our study recommended 90 ​kg/hm² as the best N fertilizer level to improve seed yield of oil flax.