Effects of Amount of Green Manure Returned to Field on Yield and Quality of Flue-cured Tobacco

The effects of amount of green manure returned to field on yield and quality of flue-cured tobacco were studied by field experiment. The results showed that significant positive correlation existed between tobacco leaf yield and small or moderate amount of green manure returned to field. Path analysis showed that moderate amount of green manure returned to field affected yield and quality of tobacco leaves, small green manure returned to field mainly affected leaf yield, while large amount of green manure returned to field mainly affected leaf quality. Therefore, the effect of moderate amount of green manure returned to field on yield and quality of tobacco leaves was best, and moderate amount of green manure returned to field was recommended in production of flue-cured tobacco.

Effect of Sweet Corn Straw Returning to the Field on Soil Fertility, Yield and Benefit

It is an important way for realizing sustainable development of sweet corn production to stabilize and improve soil fertility of cultivated land in sweet corn production region.Through the test of sweet corn straw directly returning to the field after 6seasons for 3years,the results showed that continuous single application of chemical fertilizer is not conducive to the stability of soil fertility and yield improvement,and implementation of straw returning could receive fertility,improve soil acidic conditions,and enhance the yield of sweet corn.Compared with before the test,the single application of chemical fertilizer increased soil available phosphorus,while the contents of soil organic matter,available nitrogen and available potassium decreased by 1.08,1.18 and 2.47mg/kg respectively,and the soil pH decreased by 0.15.Under the same fertilizer conditions,organic matter contents of single and double-season straw returning increased by 0.71 and 1.29g/kg,available nitrogen increased by 17.15 and 28.27mg/kg,available phosphorus increased by 0.96 and 1.73mg/kg,available potassium increased by 2.41 and 5.92mg/kg,the soil pH increased by 0.16 and 0.2.Compared with the single application of chemical fertilizer,the average yields of single and double-season straw returning increased by 7.5%and 11.8%,and their average income increased by 87.3and 117.1yuan of per mu(667m^2)respectively.

Effects of Limited Water Supply and Ridge Plotted Field on Soybean Yield and Dry Matter Accumulation

The drought in spring leads to the lack of soil water, which influents sprout and bud of crops, which furthermore affects growth and yield of crops. Studying the technology integration of bed-irrigating sowing, the mending irrigation of seedling stage and the effect of water-saving of ridge plotted field, analyzing the finger of yield and dry matter accumulation, water-saving technology integration have good effects on water-saving, water storage and increasing moisture on soil and enhancement of soybean yield.

Study on Analysis Model of Millet Yield Loss Caused by Weeds in Summer Season Millet Field

Weed management in summer season foxtall millet field was studied by evaluating weed damage and exploring competition between weeds and foxtail millet, and a few fitting models were simulated and compared by employing field plot experiment and nonlinear regression analysis. The results showed that the millet yield losses and weed density were extremely significantly correlated. Among the tested models, the determination coefficient （ R2 ） of hyperbolic model was 0.997 12, and minimum residual sum of squares was 16.174, which was considered the optimal model to simulate the competition relation between weeds and millet. The predicted equation was Y = d/（ 1. 733 ＋ 0. 018d） ; the interspecific competitiveness of weeds was 0. 577 0 and the intraspecific competitiveness was 0.010 3 ; the maximum loss rate of millet yield was 55.56%. This study had established an analysis model with high gcodness-of-fit and practical prediction which could help weed management in summer season millet field.

The Type of Low-yielding Fields,Using Direction and Land Fertility Building Measures in Suiping County

Using the evaluation indicator system for arable land fertility in Suiping County,this paper analyzes some factors influencing agricultural production,such as physical and chemical properties of soil,site conditions,soil management,and soil nutrients concerning various types of low-yielding fields in the county. In accordance with the dominant soil constraint factors and main direction of improvement,the lowyielding fields in the county are divided into four types: irrigation improvement type,waterlogging drainage type,barren soil fertilization and barrier layer type. Finally this paper offers specific guidance on the construction of arable land.

液体肥施用对滴灌棉田土壤无机氮素转化的影响

为突破氮肥利用率难以提高的瓶颈,选用液体肥替代常规肥料,旨在摸清液体肥与常规肥料施用对滴灌棉田土壤无机氮素转化的影响。2022年分别于新疆北疆8个地区(芳群农场,玛纳斯县兰州湾,昌吉市老龙河,红柳塘村,呼图壁红山村,昌吉市榆树沟,阜康市三工河乡,阜康市六运河)设置3个处理,分别为常规施肥、液体肥和减水10%+液体肥。结果表明,0~30 cm、30~60 cm土层土壤硝态氮、铵态氮含量为减水10%+液体肥>液体肥>常规施肥;土壤硝态氮、铵态氮含量均表现为滴头正下方明显高于距离滴头38 cm、-38 cm;单位面积液体肥较常规肥料养分投入量减少19.4 kg/667m^(2),但液体肥提供硝态氮、铵态氮高于常规肥料。可见,液体肥替代常规肥料在无机氮素转化方面起到正效应。

基于无人机高光谱影像的田块尺度玉米估产与生育时期优选

为实现东北黑土区田块尺度上玉米产量的精准估算与生育时期优选,本研究以我国东北黑土区的春玉米为研究对象,选取吉林省梨树县的长期定位玉米试验田,于2019、2020年利用无人机采集玉米3个关键生育时期(拔节期、吐丝期、成熟期)的冠层高光谱影像,选取10种与产量显著相关的窄波段植被指数,并结合作物农学参数与施肥信息,分别采用逐步回归、随机森林(RF)和极度梯度提升树(XGBoost)算法构建玉米产量估算模型。最后通过决定系数(R^(2))、均方根误差(RMSE)和归一化均方根误差(NRMSE)对产量模型进行精度评价,以筛选出最优估产模型。结果表明:3种产量预测模型中XGBoost模型估算精度较优,其2019年吐丝期的R^(2)、RMSE和NRMSE分别为0.93、1054.17 kg·hm^(-2)和11.68%。同时,3种模型均表现为在吐丝期估算精度最优,最佳模型——2019年吐丝期的XGBoost模型中用于玉米产量估算的指示因子——植被指数R-M、作物农学参数与施肥信息的特征重要性分别为19.72%、4.70%、62.41%。研究表明,结合无人机影像与机器学习算法并融合多源辅助信息可提高田块尺度玉米产量的估算精度,为农业生产中的作物产量精准预估提供数据支撑与科学参考。

小麦新品种安科1618的选育及高产栽培技术

安科1618是以石优17号为母本、周麦18为父本,经过有性杂交选育而成的半冬性小麦新品种,具有高产、稳产、适应性广和抗病性强等特点。本文总结分析了该品种的选育过程、区域试验全生育期、株高、穗数等农艺性状与产量、特征特性以及高产栽培技术。在2018—2019、2019—2020年皖淮小麦联合体区域试验中,平均产量为8468.4 kg/hm^(2);在2020—2021年生产试验中,平均产量为8501.3 kg/hm^(2),多次试验增产点率均超过60%。其综合农艺性状佳,抗病性较好,品质较优;高产栽培注重均匀拌种、选择适宜播期;合理施肥;田间管理注重查苗补苗、冬季灌溉、病虫草害综合防治以及田间去杂。本研究为该品种在淮河以北及沿淮地区种植推广提供参考。

麦田杂草发生及其对小麦生产的影响

为探明江苏常州地区麦田杂草发生及其对小麦生产的影响,本研究组织开展了大面积麦田杂草发生和不同耕作方式(深耕、浅旋)下的麦田杂草发生调查,并设置不同药剂处理(处理A,33%氟噻草胺·呋草酮·吡氟酰草胺;处理B,35%氟噻草胺·吡氟酰草胺;处理C,41%氟噻草胺;处理D,60%丙草·异丙隆;处理E,20%氟吡酰草胺;以清水为对照),探究各处理对杂草发生、产量等小麦生产的影响。结果表明,研究区麦田杂草发生呈逐渐加重趋势,其中单子叶杂草变化较明显,主要优势种为禾本科杂草日本看麦娘、看麦娘和菵草等。深耕较浅旋有加重杂草发生的趋势。各处理对小麦生长安全,其中,以处理A的田间杂草较少,小麦产量最高;杂草对产量的影响方面,其主要影响小麦单位面积穗数,进而影响产量,以药后50d单子叶杂草数对穗数的影响最大。研究结果为麦田杂草高效防除提供参考。

Discrepancy in Response of Rice Yield and Soil Fertility to Long-Term Chemical Fertilization and Organic Amendments in Paddy Soils Cultivated from Infertile Upland in Subtropical China

From 1990,over 17 years field experiment was carried out in paddy field cultivated from infertile upland to evaluate the response of rice productivity,soil organic carbon（SOC）,and total N to long-term NPK fertilization or NPK combined with organic amendments.The field trials included NPK（N,P,K fertilizer）,NPKRS（NPK combined with rice straw）,NPK2RS（NPK combined with double amount of rice straw）,NPKPM（NPK combined with pig manure） and NPKGM（NPK combined with green manure） and the cropping system was rice-rice（Oryza sativa L.） rotation.Annual rice yield,straw biomass,and harvesting index increased steadily with cultivation time in all treatments.Average annual rice yield from 1991 to 2006 was ranged from 7 795 to 8 572 kg ha-1 among treatments.Rice yields in treatments with organic amendments were usually higher than that in treatment with NPK.Contents of SOC and total N also increased gradually in the cultivation years and reached the level of 7.82 to 9.45 and 0.85 to 1.03 g kg-1,respectively,in 2006.Soil fertilities in treatments with chemical fertilization combined with organic amendments were relatively appropriate than those in treatment with NPK.There was obvious discrepancy between cumulative characters of rice yield and soil organic fertility in newly formed paddy field.Compared with relatively high rate of crop productivity improvement,cumulative rates of SOC and total N were much lower in our study.SOC and total N contents were still less than half of those in local highly productive paddy soils after 17 years cultivation in subtropical China.Present work helps to better understand the development of infertile paddy soils and to estimate the potential of yield improvement in this region.

Herbicide Screening and Effects on Millet Yield in Spring-seeding and Early-maturing Region

[ Objective ] Typos and dosages of herbicides suitable for spring-seeding and early-maturing region were confirmed, to provide technical support for popularization of simple and efficient cultivation techniques of millet in the region. [ Method] Four herbicides purchased from local agricultural market and two spraying methods were chosen to study plant control effect, fresh weight control effect, yield, emergence rate and plant height. [ Result ] The control effect of 10% monosulfuron against dicotyledonous weeds was more than 92%, and effects were consistent among five concentrations. Control effects against monocotylous and dicotyledonous weeds at 25 and 40 d post administration successively were atrazine sprayed after sowing and before seedling ≥10% monosulfuron ≥ MCPA- Na I〉 atrazine sprayed at 3 -5 leaf stage ≥ 2,4-D butyl ester. Spraying 3 000 and 4 500 g/hm2 atrazine after sowing and before seedling received the best effect. Spraying 2 250 and 3 000 g/hm2 10% monosulfuron and spraying 750 and 1 500 g/hm2 atrazine after sowing and before seedling increased the yield sig- nificantly. Treatments had little influence on seedling emergence included spraying 750 and 1 500 g/hm2 atrazine after sowing and before seedling, spraying 1 500 and 2 250 g/hm2 10% monosulfuron, and spraying 1 500 g/hm2 2,4-D butyl ester; spraying 10% monosulfuron and atrazine after sowing and before seed- ling inhibited growth strongly in the early stage. [ Conclusion] Suitable herbicides for the region were 10% monosulfuron with the dosage of 1 500 and 2 250 g/hm2 and atrazine sprayed after sowing and before seedling with the dosage of 1 500 g/hm2. Key words Herbicide for millet field; Screening; Yield

Use of Fluorescence and Reflectance Spectra for Predicting Okra (<i>Abelmoschus esculentus</i>) Yield and Macronutrient Contents of Leaves

In-field proximal sensing of most major crops nutrients still remains an economical and technical challenge. For this purpose, the use of effective multi-excitation fluorescence and reflectance wavelengths is explored in this work on Okra plant. Visible-near infrared (400 - 1000 nm) reflectance and multi-fluorescence data were collected at leaf scale in a chemically fertilized field by using an USB spectrometer mounted with an Arduino-based LED driver clip. N, P, K and Ca content of samples leaves were measured using reference methods. Average pods yield and leaves macronutrients content were calibrated using IRIV-PLS regression after spectra pretreatments. Single informative wavelengths bands in reflectance, red and far-red fluorescences were selected for building yield and macronutrient content models. We showed that flowering stage was more suitable for yield prediction. Moderately useful macronutrient models were found in Ca content (RPDval = 1.93, rP = 0.818) and potassium content with RPDval = 1.8, rP = 0.88. P and N yielding prediction performance of RPDval = 1.61 (rP = 0.718 ) and RPDval = 1.46 (rP = 0.56) respectively were less accurate. This study demonstrates potentiality of fluorescence and reflectance spectroscopy for accurate estimation of leaf macronutrient content and crop yield. High selectivity obtained from resulted spectral bands could lead to the development of reliable, rapid and cost-effective devices for nutrient diagnosis.

Influence of Transplanting Age on Paddy Yield under the System of Rice Intensification

Agronomic practices such as transplanting age, plant spacing, and water application regimes in irrigated paddy production can have a significant impact towards the performance in rice growth and yield. A study was conducted to investigate the optimum transplanting age for maximum rice productivity under the systems of rice intensification (SRI) technology. The study treatments adopted were three representing 8, 12 and 15 days old seedlings replicated 3 times each. The experiment was set in randomized complete block design (RCBD) and transplanted at spacing 25 cm × 25 cm between rice hills. The rice variety tested was TXD 306 Super SARO, which was recommended by the ministry of Agriculture in Tanzania. Data was collected throughout the growing season in two mixed short rains and dry season of September 2013/2014 and September 2014/2015. Data collected included biomass at vegetative, flowering and harvesting stages, total number of tillers per hill, number of productive tillers per hill, number of grains per panicle and rice grain yield at the end of the season. Data was analyzed using SAS software version 9.1. The results suggested that transplanting at younger age of 8 to 12 days was recommended for Mkindo area in Mvomero Distirct, and other areas with similar soil conditions and agro ecological characteristics.

Effects of straw and biochar addition on soil nitrogen,carbon,and super rice yield in cold waterlogged paddy soils of North China

The additions of straw and biochar have been suggested to increase soil fertility, carbon sequestration, and crop produc- tivity of agricultural lands. To our knowledge, there is little information on the effects of straw and biochar addition on soil nitrogen form, carbon storage, and super rice yield in cold waterlogged paddy soils. We performed field trials with four treatments including conventional fertilization system （CK）, straw amendment 6 t ha^-1 （S）, biochar amendment 2 t ha^-1 （C1）, and biochar amendment 40 t ha^-1 （C2）. The super japonica rice variety, Shennong 265, was selected as the test Crop. The results showed that the straw and biochar amendments improved total nitrogen and organic carbon content of the soil, reduced N2O emissions, and had little influence on nitrogen retention, nitrogen density, and CO2 emissions. The S and C1 increased NH4^＋-N content, and C2 increased NO3^--N content. Both S and C1 had little influence on soil organic carbon density （SOCD） and C/N ratio. However, C2 greatly increased SOCD and C/N ratio. C1 and C2 significantly improved the soil carbon sequestration （SCS） by 62.9 and 214.0% （P〈0.05）, respectively, while S had no influence on SCS. C1 and C2 maintained the stability of super rice yield, and significantly reduced CH4 emissions, global warming potential （GWP）, and greenhouse gas intensity （GHGI）, whereas S had the opposite and negative effects. In summary, the biochar amendments in cold waterlogged paddy soils of North China increased soil nitrogen and carbon content, improved soil carbon sequestration, and reduced GHG emission without affecting the yield of super rice.

玉米秸秆长期还田配施氮肥对不同筋性小麦品质和产量的影响

为研究玉米秸秆还田配施氮肥对不同筋性小麦品质和产量的影响,采用玉米秸秆还田(SR)、玉米秸秆不还田(NSR)为主因素,0、90、180、270、360 kg·hm^(-2)5个施氮量为副因素的裂区设计,测定了小麦千粒质量、容重、产量、硬度、蛋白质、湿面筋、沉降值、吸水率、面团形成时间、面团稳定时间、延展性、最大延伸阻力和延伸面积等指标。结果表明:玉米秸秆还田降低了小麦的蛋白质和湿面筋含量,且中筋小麦青农2号的降幅大于高筋小麦济南17;玉米秸秆还田显著降低了青农2号的硬度、沉降值、吸水率、面团形成时间和延展性,显著提高了济南17的硬度、吸水率、延展性、最大延伸阻力和延伸面积;2个小麦品种的蛋白质、湿面筋含量均随着施氮量的增加而增加;青农2号的沉降值、吸水率、面团形成时间、面团稳定时间、延展性、最大延伸阻力和延伸面积均随着施氮量的增加而增加,而济南17的吸水率、延展性、最大延伸阻力和延伸面积在施氮量为180 kg·hm^(-2)时最高,沉降值、面团形成时间、面团稳定时间在施氮量为270 kg·hm^(-2)时最高;SR显著提高了小麦产量,比NSR增产15.2%~31.0%,且施氮量为180 kg·hm^(-2)时,小麦产量最高。因此,中筋小麦青农2号的最佳种植模式为玉米秸秆还田+施氮180 kg·hm^(-2),高筋小麦济南17的优质高产栽培模式为玉米秸秆还田+施氮180~270 kg·hm^(-2)。

有机无机肥配施对低产田春玉米生长及生产效益的影响

为探索黄土高原半干旱区低产田春玉米的最优施肥模式和方法,在有机肥、化肥、有机肥与无机肥配施等不同施肥条件下,对春玉米的病虫害发生情况、产量及经济效益开展了研究分析。结果表明,有机无机肥配施能够减轻玉米病虫害发生,促进植株生长。各施肥处理均能有效提高玉米产量,增产15.28%~85.45%,其中以复合施肥(羊粪+化肥+硫酸亚铁+腐殖酸+生物菌肥)处理折合产量最高,为12497.4kg/hm^(2),较不施肥处理增产85.45%;羊粪+商品有机肥+化肥配施次之,折合产量11830.4kg/hm^(2),较不施肥处理增产75.55%。羊粪配施化肥处理纯收益最高,较不施肥处理和单施化肥处理分别增加了5360.6、3029.6元/hm^(2)。综合考虑产量和经济效益,表现较优的施肥方式是羊粪配施化肥、羊粪+商品有机肥+化肥配施、复合施肥(羊粪+化肥+硫酸亚铁+腐殖酸+生物菌肥),在低产田改良上的保粮增收效果明显。

稗草对机械穴直播水稻产量的影响及其生理机制

为了给机械穴直播水稻高产栽培和杂草综合治理提供科学依据,以苏粳4699为试验材料,自水稻播种后7 d至成熟分别与光头稗和无芒稗共生,以无杂草的水稻处理为对照,研究机械穴直播条件下稗草对水稻产量的影响及其生理机制。结果表明,与对照相比,水稻与稗草共生后产量显著降低,但处理间存在较大差异。光头稗处理显著降低了水稻的每穗粒数、结实率和千粒重,造成水稻减产13.0%,而无芒稗处理的水稻减产55.2%,这主要是由水稻单位面积穗数、每穗粒数、结实率和千粒重的显著降低所致。光头稗和无芒稗处理还显著降低了机械穴直播水稻灌浆期的根系氧化力、剑叶净光合速率、籽粒中玉米素+玉米素核苷含量、灌浆早期的脱落酸含量,籽粒中蔗糖合酶、ADP葡萄糖焦磷酸化酶、淀粉合酶和淀粉分支酶的活性以及成熟期的地上部干物质积累量,上述生理指标的降低可能是机械穴直播水稻在与稗草共生过程中产量降低的重要原因。

天水市旱作区春玉米—冬油菜秸秆带膜翻压还田栽培模式研究

为解决区域内春玉米—冬油菜一膜两用技术中秸秆利用不合理、土壤有机质含量低、有机肥投入不足、化肥施用不合理、土壤水分利用不足、肥料利用率较低等一系列问题,在天水市旱作区开展了春玉米—冬油菜秸秆带膜翻压还田栽培模式研究,以期为区域内化肥减施、地力提升和农业可持续发展提供依据。结果表明,秸秆粉碎带膜翻压还田可以提高玉米籽粒产量7.96%、冬油菜籽粒产量9.91%,增加0~20 cm土壤有机质、全磷、有效磷含量(分别增加2.53 g/kg、0.08 g/kg、10.93 mg/kg),缓冲土壤pH值,影响土壤速效钾、硝态氮和铵态氮水平。

Application of geometric midline yield criterion to analysis of three-dimensional forging

A kinematically admissible continuous velocity field was proposed for the analysis of three-dimensional forging.The linear yield criterion expressed by geometric midline of error triangle between Tresca and Twin shear stress yield loci on the π-plane,called GM yield criterion for short,was firstly applied to analysis of the velocity field for the forging.The analytical solution of the forging force with the effects of external zone and bulging parameter is obtained by strain rate inner product.Compression tests of pure lead are performed to compare the calculated results with the measured ones.The results show that the calculated total pressures are higher than the measured ones whilst the relative error is no more than 9.5%.It is implied that the velocity field is reasonable and the geometric midline yield criterion is available.The solution is still an upper-bound one.

不同施肥处理对退砂田西瓜产量、品质及养分吸收的影响

为筛选出适合退砂田西瓜种植的施肥措施,采用田间大区对比试验,以金城5号西瓜为供试作物,研究了不施肥(CK)、大量元素水溶肥、大量元素水溶肥+生物菌肥、生物菌肥、沼液肥对西瓜产量、养分吸收和品质的影响。结果表明,水溶肥+生物菌肥处理下西瓜经济产量最高,为51.4 t·hm^(-2)。水溶肥或其配施生物菌肥促进了西瓜植株、果实和地上部氮吸收,同时促进了果实和地上部钾吸收。水溶肥处理下西瓜氮肥利用率最高(31.2%),沼液肥处理下磷(15.5%)、钾(39.2%)肥利用率较高。西瓜总糖与总酸、维生素C含量之间分别呈显著和极显著正相关。施肥处理显著提高了西瓜品质,水溶肥+生物菌肥处理效果明显。因此,综合考虑西瓜的产量、养分吸收和品质,退砂田施用水溶肥或其配施生物菌肥可实现西瓜高产优质生产。