辽西地区垄作和平作保护性耕作方式比较研究

比较了平作和垄作下不同保护性耕作方式对土壤水分、温度和作物生长发育和产量的影响。结果表明,几种耕作方式中平作的平均产量都要高于垄作,其增产率在11.38%￣15.20%之间。在相同的垄作或平作方式下,不同的保护性耕作方式的增产幅度不同,其中秸秆还田增产幅度最大。平作方式的出苗率、叶面积指数、根干重和干物重都高于垄作,但不同的保护性耕作方式其各项指标变化有所不同。平作下保护性耕作方式的土壤含水量高于垄作;垄作方式有一定的增温效应,尤其在苗期的土壤表层。     

保护性耕作对华北平原土壤团聚体特征的影响

 【目的】研究华北平原保护性耕作制度对土壤团聚数量、大小和稳定性的影响。【方法】本文采集了华北平原河北栾城试验站经过四年保护性耕作(旋耕和免耕)与传统耕作(翻耕)处理下原状土壤样品，测定了土壤容重、有机质和粘粒含量等物理性质，重点应用干筛和湿筛法分析了土壤团聚体数量、分布和分形维数。【结果】表层(0-5cm)土壤容重的大小顺序为免耕>旋耕>翻耕，免耕使表层土壤的容重显著增加；旋耕与翻耕的表层土壤容重差异不显著，但旋耕使10-20cm的土壤容重明显增加。干筛法分析表明，免耕处理下0-10cm内>0.25mm团聚体含量、平均重量直径(Mean Weight Diameter，MWD)和几何平均直径(Geometric Mean Diameter，GMD)均高于旋耕处理和翻耕处理，而旋耕与翻耕处理间没有显著的差异；湿筛法分析表明，土壤中的团聚体以非水稳性团聚体为主，水稳性团聚体的 和GMD大小顺序为免耕>旋耕>翻耕；在0-5cm土层内免耕处理的水稳性团聚体分维数(D)最小，而旋耕下5-10cm层的分形维数D值显著高于翻耕、免耕处理，说明旋耕使得该层内土壤团聚体的稳定性降低。【结论】经过四年保护性耕作试验，免耕处理促进表层土壤团聚体的形成并提高起稳定性，旋耕和翻耕处理由于对土壤的强烈扰动，降低了耕作深度内土壤团聚体的团聚度和稳定性；在10-30cm三种耕作处理间没有显著差异。     

Genotype×tillage interaction and the performance of winter bread wheat genotypes in temperate and cold dryland conditions

Growing concerns for food security and the alleviation of hunger necessitate knowledge-based crop management technologies for sustainable crop production. In this study, 13 winter bread wheat genotypes (old, relatively old, modern, and breeding lines) were evaluated under three different tillage systems, i.e., conventional tillage (CT, full tillage with residue removed), reduced tillage (RT, chisel tillage with residue retained) and no-tillage (NT, no-tillage with residue retained on the soil surface) in farmer's fields under rainfed conditions using strip-plot arrangements in a randomized complete block design with three replications in the west of Iran (Kamyaran and Hosseinabad locations) over two cropping seasons (2018–2019 and 2019–2020).The main objectives were to investigate the effects of tillage systems and growing conditions on the agronomic characteristics, grain yield and stability performance of rainfed winter bread wheat genotypes.Significant (P<0.01) genotype×tillage system interaction effects on grain yield and agronomic traits suggested that the genotypes responded differently to the different tillage systems. The number of grains per spike and plant height were positively (P<0.0) associated with grain yield under the NT system, so they may be considered as targeted traits for future wheat breeding. Using statistical models, the modern cultivars (“Sadra” and “Baran”) were identified as high yielding and showed yield stability across the different tillage systems. As per each tillage system, genotype “Sadra” followed by “Zargana-6//Dari 1-7 Sabalan” exhibited higher adaption to CT; while cultivars “Jam” and “Azar2” showed better performance under the RT system; and cultivars “Varan” and “Baran” tended to have better performance expression in the NT condition.The increased grain yields achieved in combination with lower costs and greater profits from conservation agriculture suggest that adapted cultivar and NT systems should be evaluated and promoted more widely to farmers in the west of Iran as an attractive package of crop management technologies.In conclusion, variations in the performance of genotypes and the significant genotype×tillage system interaction effects on grain yield and some agronomic traits assessed in this study suggest that the development and selection of cultivars adapted to the NT system should be considered and included in the strategies and objectives of winter wheat breeding programs for the temperate and cold dryland conditions of Iran.     

鲁东丘陵区玉米—小麦一年两熟一体化耕作技术体系研究

本研究将夏玉米、冬小麦轮作作为一个整体,采用免耕、深松、翻耕3种耕作措施,结合秸秆100%粉碎还田和秸杆不还田2种覆盖水平,设计了10套耕作技术体系,探讨了周期内不同的耕作技术体系对土壤含水量、容重、地温及作物产量的影响,筛选出适宜鲁东丘陵区玉米小麦一年两熟的耕作技术体系,并对全程免耕这一新型耕作技术在鲁东丘陵区的适宜性进行了鉴定。两年试验结果表明：玉米免耕100%还田＋小麦深松100%还田耕作技术体系,有利于提高土壤水分含量,提高水分利用率,增加作物产量,适宜在鲁东丘陵区推广应用;因土壤肥力特别是有机质含量较低,全程免耕对土壤容重及地温影响不利,最终影响产量,暂不适宜在鲁东丘陵区推广应用。     

Influence of Conservation Tillage on Soil Aggregates Features in North China Plain

Tillage greatly influences the aggregation and stability of soil aggregates. This study investigated the effects of conservation tillage on soil aggregate characteristics. During a four-year study period （2001-2005）, soils were sampled from no-tillage （NT）, rotary tillage （RT）, and conventional tillage （moldboard tillage, CT） plots at the Luancheng Agriculture and Ecology Experimental Station in Hebei Province, China, and the amount, size distribution, and fractal dimension of the aggregates were examined by dry and wet sieving methods. The results indicated that NT significantly increased the topsoil （0-5 cm） bulk density （BD）, while RT maintained a lower BD as CT. Dry sieving results showed that NT had higher macro-aggregate content （R0.25）, and a larger mean weight diameter （MWD） and geometric mean diameter （GMD） than other treatments in the 0-10 cm layer, while RT showed no difference from CT. In wet sieving, results showed that most of the aggregates were unstable, and the MWD and GMD of water-table aggregates showed the trend of NT 〉 RT 〉 CT. At 0-5 cm layer, the fractal dimension （D） of water-stable aggregates under NT was lower than it was under RT and CT. At 5-10 cm, RT yielded the highest D, and showed stability. After four years, NT increased the aggregation and the stability of soil aggregates; while due to intense disturbance, the aggregation and stability of the upper layer （0-10 cm） under RT and CT decreased.     

土壤耕作技术对小麦出苗质量、根系功能及粒重的影响

【目的】 针对黄淮平原农作区一年两熟条件下玉米秸秆还田严重影响麦苗质量的突出问题,探索适宜的土壤耕作技术以提高小麦幼苗质量,最终提高产量。【方法】 2016—2018年连续2年,在河南省新郑市辛店镇黄岗村开展田间试验。采用随机区组设计,将翻耕、耙、镇压3个因素组合配套实施8个处理,分别为深翻耕+旋耕（DT+RT;DT：30 cm,RT：15 cm）、深翻耕+耙（DT+H）、深翻耕+旋耕+镇压（DT+RT+C）、深翻耕+耙+镇压（DT+H+C）、旋耕（RT）、旋耕+耙（RT+H）、旋耕+镇压（RT+C）、旋耕+耙+镇压（RT+H+C）。对小麦出苗率及幼苗质量进行调查,并在越冬期、返青期、拔节期、抽穗期、灌浆期、蜡熟期对根系进行调查分析,分别在灌浆期对小麦籽粒性状、收获后对小麦产量及其构成因素进行调查分析。【结果】 小麦播种后20 d,不同土壤耕作处理间幼苗质量差异显著。旋耕后出苗整齐度高于深翻耕,而深翻耕后出苗率、基本苗数和株高高于旋耕。相同耕、镇压因素处理下,耙后出苗率增幅为1.0%—5.7%,相同耕、耙因素处理下,镇压后出苗率增幅为0.06%—8.3%;同时深翻耕后,极少出现缺苗、断垄,RT处理缺苗、断垄的累计长度最高,两年平均为55 cm。从越冬期到蜡熟期,不同土壤耕作处理的根系活力均呈现“高-低-高-低”的变化趋势,DT+H+C处理最高;在越冬期和拔节期,镇压和耙处理后,与无镇压、耙处理相比,根系活力均提高。单株次生根数目在抽穗期达到最大,DT+H+C处理最高,两年最高值分别为45.2条与40.2条;与无耙处理相比,耙处理后,单株次生根数目最高增加14.8%,与无镇压处理相比,镇压处理后,单株次生根数目最高增加12.2%。花后5—10 d,DT+H+C和RT+H+C处理的籽粒灌浆速率增长幅度显著高于其他处理,开花后20 d达到峰值,其中DT+H+C处理籽粒灌浆速率比其他处理高1.0%—19.4%,达显著水平。灌浆期籽粒千粒重,在花后0—15 d,DT+H+C处理增长最快,DT+RT处理增长最慢,花后25—30 d,DT+H+C处理千粒重最高,较RT处理提高20.8%。从不同土壤耕作技术对籽粒产量及其构成因素的影响来看,DT+H+C处理的籽粒产量最高;耙和镇压处理的单位面积穗数、穗粒数和千粒重的变化并不规律,籽粒产量均有明显提升,幅度为1.4%—12.2%。经济效益方面,与当地以往耕作方式RT相比,RT+H、RT+H+C、RT+C、DT+H+C、DT+H处理所得效益均高于RT处理,其中DT+H+C处理产生经济效益最高,两年平均比RT处理高12.3%。【结论】 黄淮平原农作区当前一年两熟制条件下,不同土壤耕作技术影响幼苗质量,旋耕有利于出苗的整齐度提高,而深翻耕则有利于出苗率及幼苗均匀度提高,株高增高,为冬前形成壮苗奠定基础;深翻耕将耕层加深,利于根系下扎,促进次生根数目的增加以及耕层根系活力的提高,间接影响籽粒产量。综合考虑植株根系生长发育、生育后期籽粒灌浆速率、粒重形成和产量表现等,研究认为黄淮农作区DT+H+C处理土壤耕作技术是当前的最佳选择。     

Influence of preceding crop and tillage system on forage yield and quality of selected summer grass and legume forage crops under arid conditions

Among the crop production factors, preceding crop and tillage management affect the sustainable use of soil resources and ultimately crop growth and productivity. This study aimed at investigating the impact of preceding winter crops (grass or legume) and different tillage systems on forage yield, quality and nutritive values of three summer grass (Sudan grass, pearl millet and teosinte) and two legume forage crops (cowpea and guar) under arid conditions. The results exhibited that growing forage crops after legumes (as berseem clover) produced the highest fresh and dry forage yields and quality attributes compared with grasses (as wheat) with the exception of crude fiber content, which was decreased. Moreover, tillage practices showed positive impact on forage yields and quality attributes. The maximum forage yields and quality parameters were recorded under conventional tillage (CT) practice compared with reduced tillage (RT) and no-tillage (NT) systems. Among the evaluated crops, the highest yields of fresh forage, dry forage, crude fiber, crude protein and total digestible nutrient were exhibited by grass forage crops (Sudan grass, pearl millet and teosinte), whereas the highest crude protein content and the digestible energy values were produced by legume forage crops (cowpea and guar). The maximum fresh forage, dry forage, crude fiber, crude protein, total digestible nutrient and digestible crude protein yields were produced by pearl millet followed by Sudan grass under CT and RT after berseem clover. The highest net return was recorded by sowing pearl millet after berseem clover and applying CT followed by RT practices, which could be recommended for the commercial production. Moreover, it could be assumed that the combination of growing grass forage crops after legume crops under CT or RT systems could enhance forage crop yield and quality with an improvement in soil properties for sustainable agriculture with low cost and the highest net income.     

Spatial Analysis of Maize Response to Nitrogen Fertilizer in Central New York

An increasing number of farmers are considering the use of site-specific nitrogen (N) applications to maize (Zea mays L.) as a way of maximizing yield potential while minimizing fertilizer cost. The objectives of this 3-years experiment were to evaluate the spatial structure of yield response to N fertilizer and investigate the potential for site-specific N management under maize production in New York. Four experimental N rates (50, 110, 160, or 220 kg ha¹), two tillage systems (chisel till and zone-till) and two crop rotations (maizemaize and maizesoybean (Glycine max L.)) were superimposed over a 12 ha field in central New York State with a complex of Honeoye-Lima, Kendaia, and Lima soils ranging from moderately well to poorly drained soils. Pre-sidedress soil nitrate tests (PSNT) showed significant spatial structure but did not conform to that for crop N response, indicating that N fertilizer recommendations based on PSNT results cannot be simply applied in a site-specific management approach. Optimal N rate varied from 110 kg ha ¹ for the dry years 1999 and 2000 to 220 kg ha¹ for 1998, with a warm wet spring. Tillage treatments were generally comparable in N response. Spatial yield response analysis showed limited field-scale regionalization of both yield and profit response to N, suggesting that site-specific application of nitrogen is impractical. The greatest source of variability in N requirements was observed with the annual effects of weather, and presents a greater potential for precise N application than site-specific application. Annual variations in optimum N rate were not related to annual yield differences and yield potential itself does not appear to be a good predictor of N needs.     

Impact of Tillage and Herbicides on Weed Density,Yield and Quality of Cotton in Wheat Based Cropping System

Conservation tillage may improve yield of cotton in addition to improvement in soil quality if practiced for longer period. However, the practice may not be productive in short-term particularly when severe weeds are infesting the crops such as Cynodon dactylon, Conyza canadensis, Tribulus terrestris, and Cyperus rotundus, etc. Recent studies indicate that conventional tillage (CT) is more productive than zero tillage (ZT)/reduced tillage (RT). Performance of cotton under three tillage systems, viz., ZT, RT and CT; and five herbicides, i.e., haloxyfop-R-methyl 10.8 EC (108 g a.i. ha^?1), lactofen 24 EC (168 g a.i. ha^?1), haloxyfop 10.8 EC + lactofen 24 EC, hand weeding, and weedy check were evaluated during 2010-2011 at Gomal University, D.I. Khan, Pakistan, to explore the best management option for effective weed control, enhanced yield and quality of cotton grown after wheat. The results revealed that hand weeding and Haloxyfop as post emergence alone or in combination with Lactofen reduced weed density to the minimum irrespective of the tillage systems. Excessive rainfall and cooler temperature limited cotton growth and yield in 2010. The adverse weather conditions had more adverse effect on boll weight under ZT and RT than CT. Haloxyfop + lactofen produced higher seed cotton yield in RT than ZT, however, it could not exceed CT. Broad-spectrum herbicides × CT produced the highest number of bolls/plant, boll weight and seed cotton yield. Fiber quality and net returns were also the highest in broad-spectrum herbicides × CT. In conclusion, broad-spectrum herbicides under CT were more productive in wheat based cropping system on silty clay soil of D.I. Khan.     

耕作方式与秸秆还田对冬小麦/夏玉米籽粒糖类积累和产量的影响

试验设在冬小麦/夏玉米轮作区的长期定位大田中,在常规耕作、旋耕、耙耕和免耕4种耕作方式下分别设置秸秆还田与不还田两种处理,研究不同耕作方式与秸秆还田与否对小麦、玉米收获期籽粒可溶性糖含量、蔗糖含量及淀粉累积的影响。结果表明:收获期籽粒中淀粉的合成与蔗糖的积累量、可溶性糖含量没有明显的关系,在淀粉积累量较低的耕作方式下,蔗糖含量与可溶性糖含量却没有相应的降低,说明籽粒的贮存容量和物质转化能力成为影响淀粉积累的主要因素。旋耕和免耕的籽粒贮存容量和物质转化能力明显高于耙耕与常规耕作,从而使千粒重明显增加,加之耕作对穗数的影响,最终表现为旋耕与免耕的产量较高。秸秆还田有利于小麦产量的增加,但对玉米产量的影响不大。因此,少免耕配合秸秆还田有利于籽粒的充实,从而提高作物产量。     

保护性耕作对复播油葵干物质动态变化的影响

为研究保护性耕作栽培条件下复播油葵干物质积累规律,指导生产实践。采用单因素随机区组试验设计,于复播油葵不同生育期取样,测定各器官干物质积累量。结果表明,免耕复播油葵可以使生育期延长;复播油葵干物质积累呈直线上升趋势,总体干物质积累水平犁地处理低于免耕处理;干物质增长速率呈单峰曲线变化;2种耕作条件下,净干物质分配均随生长中心的转移而发生变化;免耕处理生物产量、籽粒产量及收获指数略低于犁地处理。而花盘直径、结实率及百粒质量等性状却优于犁地处理。     

Deep chiseling of soil under irrigation conditions

The advantage of fall soil tillage by loosening with an experimental chisel implement to a depth of 40–42 cm compared with moldboard plowing with a share plow to a depth of 25–27 cm is shown. Original Russian Text ? V.I. Pyndak, V.F. Loboiko, V.N. Pavlenko, 2009, published in Doklady Rossiiskoi Akademii Sel’skokhozyaistvennykh Nauk, 2009, No. 2, pp. 54–55.     

保护性耕作对太行山前平原土壤热水解和酸解有机碳的影响

【目的】研究传统耕作转为保护性耕作后土壤热水解碳（HWC）和酸解碳（AHC）的分布和积累特征。【方法】2001年在河北栾城设置翻耕+玉米秸秆不还田（CK）、翻耕+玉米秸秆粉碎还田（CT）、旋耕+玉米秸秆粉碎还田（RT）和免耕玉米秸秆直立还田（NT）4个处理。2007年小麦收获后,采集0—5 cm、5—10 cm、10—20 cm和20—30 cm土层样品,测定热水解有机碳（HWC,80℃水浴下提取24 h）和酸解有机碳（AHC,6 mol•L-1 HCl,105℃下提取4 h）的浓度,分析两种活性碳的层化比率值（SR）,并基于等效质量碳库储量计算方法,比较了不同耕作处理对土壤活性碳分布和储量的影响。【结果】连续6年保护性耕作后,HWC和AHC在土壤表层积累,具有较高的层化比率值。在0—10 cm土层,保护性耕作（RT和NT）系统HWC的SR值（1.68—1.98）显著高于传统翻耕（CK和CT）处理（1.30—1.50）,保护性耕作下AHC的SR值（1.62—1.83）亦高于传统翻耕（1.12—1.63）。与传统翻耕CT相比,保护性耕作系统0—30 cm剖面的HWC储量无显著变化,但免耕显著增加了AHC的储量。【结论】在太行山前平原地区,保护性耕作导致土壤剖面中HWC和AHC在表层积累,呈现高度层化特征,可能会潜在影响土壤质量和农田固碳速率。     

不同耕作方式和工作深度对玉米生产的影响

为了比较不同耕作方式和工作深度对玉米生产的影响,在华南农业大学农场进行了两组对比试验,试验土壤为沙壤土和粘壤土,试验作物为玉米。第一组试验中安排了５种耕作方式,分别为犁耕加圆盘耙（ＭＢ＋ＤＨ）,凿形耕（ＣＨ）,圆盘耙两次（ＤＨ２）,旋耕（ＲＴ）和不耕（ＮＴ）,第二组试验中安排了２种耕作方式,犁耕加圆盘耙（ＮＤＬ）和犁耕、圆盘耙加深松（ＮＬ）。试验结果表明,不同的耕作方式和工作深度对土壤容重、土壤耕     

不同耕作方式麦田土壤温度及其对气温的响应特征 ——土壤温度日变化及其对气温的响应

 【目的】针对以往研究在土壤温度观测和不同耕作条件下土壤温度效应规律上的不足,研究了华北平原不同耕作方式冬小麦田土壤温度日变化及其对气温的响应特征。【方法】试验于河北省栾城县设置翻耕、旋耕和秸秆覆盖免耕处理,采用热脉冲-时域反射技术,连续监测2004-2005年冬小麦生育期土壤温度和气温。【结果】各层次土壤温度日变化随气温呈正弦函数变化;土壤温度日变化随土壤深度呈“锥形”;2.5～80 cm土壤深度每增加5 cm,土壤温度随气温的变化滞后1.2 h左右;不同耕作方式土壤日最高和最低温度均具有显著差异,秸秆覆盖度是其主要影响因素之一;免耕在冬小麦活动期,显著降低了2.5 cm土层土壤最高温度0.66～4.85℃,而在越冬期提高最低温度0.64～0.87℃;冬小麦生长前期（出苗-拔节）免耕较其他处理显著降低了2.5 cm土层土壤温度日变化幅度,其中较翻耕降低0.65～5.21℃,较旋耕降低0.48～3.89℃。【结论】不同耕作方式各层次土壤温度均极显著响应气温变化;耕作方式主要影响土壤温度的变化幅度而且主要表现在冬小麦生长前期;免耕在冬小麦活动期表现为降温效应,究其原因是由于较大程度地降低高温而较小程度地提高低温;越冬期表现增温效应是由于显著提高了各个时刻的土壤温度。     

The effect of conservation tillage on crop yield in China

Traditional agricultural practices have resulted in decreased soil fertility, shortage of water resources and deterioration of agricultural ecological environment, which are seriously affecting grain production. Conservation tillage (CT) research has been developed and applied in China since the 1960s and 1970s, and a series of development policies have been issued by the Chinese government. Recent research and application have shown that CT has positive effects on crop yields in China. According to the data from the Conservation Tillage Research Center (CTRC), Chinese Ministry of Agriculture (MOA), the mean crop yield increase can be at least 4% in double cropping systems in the North China Plain and 6% in single cropping systems in the dryland areas of North-east and North-west China. Crop yield increase was particularly significant in dryland areas and drought years. The mechanism for the yield increase in CT system can be attributed to enhanced soil water content and improved soil properties. Development strategies have been implemented to accelerate the adoption of CT in China.     

No-tillage agriculture

The no-tillage cropping system, a combination of ancient and modern agricultural practices, has been rapidly increasing in use. By the year 2000, as much as 65 percent of the acreage of crops grown in the United States may be grown by the no-tillage practice. Soil erosion, the major source of pollutants in rural streams, is virtually eliminated when no-tillage agriculture is practiced. The no-tillage system reduces the energy input into corn and soybean production by 7 and 18 percent, respectively, when compared to the conventional tillage system of moldboard plowing followed by disking. In addition, crop yields are as high as or higher than those obtained with traditional tillage practices on large areas of agricultural land.     

Effects of Straw Returning with Different Tillage Patterns on Corn Yield and Nitrogen Utilization

To explore the effects of farming methods,straw returning and their interaction on corn yield and nitrogen utilization,the experiment was conducted for two consecutive years from 2016 to 2017 at the Xiangyang Experimental Base of Northeast Agricultural University in Heilongjiang Province of China.The method of combining farming with straw returning was used and six treatments as rotary tillage (R)+no straw returning (K),rotary tillage (R)+straw returning (S),tillage (T)+no straw returning (K),tillage (T)+straw returning (S),tillage (T)+subsoiling (D)+no straw returning (K) and tillage (T)+subsoiling (D)+straw returning (S) were set to study the effects of different tillage methods and straw returning on corn yield and nitrogen accumulation and utilization.The corn yield,nitrogen accumulation,nitrogen transport,grain weight and dry matter accumulation of tillage (T)+subsoiling (D) and tillage (T) were significantly higher than those of rotary tillage (R) treatment.Meanwhile,the corn yield,nitrogen accumulation and dry matter accumulation of TD treatment were significantly higher than those of T treatment;the corn yield,dry matter accumulation,kernel weight,nitrogen dry matter production efficiency and nitrogen grain production efficiency of S treatment were significantly higher than those of K treatment.Among the treatments,the yield,nitrogen accumulation and utilization efficiency of TDS,TS and TDK were the highest.The yield,nitrogen accumulation and nitrogen transport of TDS were significantly higher than those of TS.In 2016,TDS production increased by 7.30% and 8.20% compared with TS;and TDS nitrogen accumulation increased by 6.78% and 9.50% compared with TS,while the yield and nitrogen grain production efficiency were significantly higher than those of TDK.Therefore,under the conditions of this experiment,on the basis of straw returning,tillage+subsoiling was the suitable farming method.     

耕作措施对黑龙江白浆土区玉米生育性状及产量的影响

针对黑龙江省白浆土区干旱频繁发生、土壤风蚀严重的特点,采取原茬播种、打茬播种、旋耕播种及翻地处理四种耕作措施进行对比试验。结果表明,打茬处理的出苗率最高,达90%,其次为旋地处理,出苗率达到89%。不同耕作措施对土壤墒情的影响不同,保墒效果是原茬〉旋地〉打茬〉翻地。打茬处理的产量最高,比原茬处理增产15.4%,比翻地处...     

冬小麦-夏玉米生产体系中播前耕作对夏玉米产量形成的影响

【目的】黄淮海夏玉米区是典型的一年两熟制种植制度区,统筹研究冬小麦和夏玉米播前耕作对夏玉米产量形成的影响,为冬小麦夏玉米周年高产高效生产耕作模式的改进提供科学依据。【方法】以郑单958（ZD958）为试验材料,设置冬小麦播前旋耕夏玉米播前免耕（RN）、冬小麦播前翻耕夏玉米播前免耕（MN）与冬小麦播前翻耕夏玉米播前旋耕（MR）3个试验处理,其中RN作为对照（CK）,研究冬小麦和夏玉米播前耕作对夏玉米产量及其构成因素、叶面积指数、干物质积累与分配和籽粒灌浆特性等的影响。【结果】冬小麦与夏玉米播前耕作均对夏玉米产量影响显著。与RN相比,MN和MR处理夏玉米的叶面积指数、花后干物质积累量、花后干物质积累所占比例、籽粒最大灌浆速率分别提高15.01%、21.14%、3.21%、15.00%和16.44%、24.92%、4.49%、12.60%,即冬小麦播前翻耕提高了夏玉米叶面积指数、花后干物质积累及其向籽粒分配比例和籽粒最大灌浆速率,进而提高穗粒数与粒重,有利于产量提高。与RN相比,MN和MR处理的产量分别提高24.03%和30.61%。夏玉米播前旋耕对干物质向籽粒分配比例,籽粒灌浆速率无显著影响,但显著提高了出苗率,进而增加群体数量,提高产量;与MN相比,MR处理的出苗率提高6.29%,这是其产量较MN提高5.23%的主要原因。【结论】与冬小麦播前旋耕夏玉米播前免耕（RN）相比,冬小麦播前翻耕夏玉米播前旋耕（MR）与冬小麦播前翻耕和夏玉米免耕（MN）均显著提高夏玉米的产量。尽管冬小麦播前翻耕夏玉米播前旋耕（MR）的产量较冬小麦播前翻耕和夏玉米免耕（MN）高5.23%,但结合生产实际,冬小麦播前翻耕和夏玉米免耕播种（MN）更有利于该区域夏玉米的高产高效生产。