稻田春玉米不同育苗方式的效应

在稻田春玉米进行不同育苗方式与露地直播(CK)的对比试验。结果表明：地膜育苗移栽玉米生长发育进程快,能提早成熟5～9d;降低株高10.0～18.2cm,穗位高14.8～16.2cm;并且增加单株穗粒数和千粒重,从而显著增加产量和经济收益。本试验结果为稻田春玉米品种选择最适密度的确立提供技术参考。     

不同育秧方式对杂交晚稻生长发育及产量性状的影响

2002年，以杂交晚稻金优207为供试品种，进行了旱地育秧、盘育抛秧、两段育秧和湿润育秧的田间栽培比较试验，对4种育秧方式下杂交晚稻的生长发育及产量性状进行了系统的苗情观察调查。结果表明：与湿润育秧比较，旱地育秧、盘育抛秧、两段育秧的秧苗素质好，根系发达白根多，干物质含量高；营养生长势旺盛，返青快，分蘖发生早而多，生育进程提早，全生育期缩短；综合经济性状好，成穗率高，穗大粒多，籽壮产量高。     

栽培方式对玉米农艺性状及产量的影响

在黑龙江省佳木斯地区选用当地主栽品种,系统比较了不同栽培方式对玉米生长发育及产量的影响。结果表明：栽培方式对玉米生长发育及产量影响很大,行间覆膜处理,因前期保水和保温,使株高、茎粗、叶面积、根干重及产量均高于其他栽培方式处理。     

不同镇压方式对玉米生长发育及产量的影响

对玉米播种采用0.4kg/cm^2 沟种 0.4kg/cm^2强度的镇压可以得出以下结构：（1）出苗率可以提高18.5个百分点；（2）播后24h0-10cm耕层土壤不量可提高0.86个百分点，10－20cm耕层土壤含水量可提高0.52个百分点。播后48h0-10cm耕层土壤含水量可提高2.88个百分点，10－20cm可提高1.66个百分点；（3）0－10cm土壤容重可增加0.12g/cm^3；（4）4个生育阶段的鲜、干重均有较大提高；（5）利于产量的增加。     

辽宁省不同生态区玉米产量及农艺性状差异研究

以28个玉米品种为试材,在5个密度下对辽宁省4个生态区玉米产量和农艺性状的差异进行研究.结果表明,辽西地区的产量最高,辽北、辽中和辽南地区分别比辽西地区低3.39％、6.06％和19.92％;辽中、辽北和辽南地区植株的株高均较高,辽西地区株高最低;辽南地区的叶面积指数最大,辽北、辽西和辽中地区分别比辽南地区低5.98％、12.64％和18.03％.辽西地区的光照条件突出,中后期群体最大叶面积指数持续时间和光合有效时间均较长,利于构建高密度群体,在肥水充足条件下容易获得高产;辽北地区的光照条件较好,群体最大叶面积指数持续时间和光合有效时间均较长,但灌浆期伴随降水而产生的较低日照时数对产量有一定影响;辽南和辽中地区中后期光照条件较差,使群体最大叶面积指数持续时间和光合有效时间均较短,产量均较低.     

玉米纸筒育苗移栽对玉米产量和生育性状的影响

玉米纸筒育苗移栽可使株高矮化，德位降低，提高栽培密度，密度较直播4．5万株／hm2增加到6．5万株／hm2，产量可由直播对照的11946．4kg/hm2啬到15444．2kg/hm2，增加了29．3％，纸筒育苗移栽是玉米生产的一项增产措施。     

不同覆膜方式对旱地玉米生长发育和产量的影响

针对西北半湿润偏旱区(甘肃镇原)年降水量少、季节分布不均、特别是玉米生产中春旱严重等问题,研究6种不同覆膜方式对旱作玉米出苗率、干物质积累量、株高、叶面积指数、生育时期和产量的影响。结果表明,双垄面全膜覆盖沟播提高了玉米出苗率和出苗速度,提早成熟,整个生育期玉米株高、叶面积指数和干物质积累量始终大于其他处理,增产效果明显,是旱作区进一步挖掘降水潜力和高产田创建的有效途径。     

夏玉米不同种植方式生长发育规律研究

1998－1999年以掖单22号为材料，采取塑盘育苗带土移栽与麦田套种，麦收后直播3种不同种植方式，研究了夏玉米的生长发育进程，植株高度，田间生长整齐度和叶面积系数，根系发育，干物质积累以及产量情况，明确了夏玉米塑盘育苗带土移栽的方式比麦田套种和麦后直播具有明显的生长发育优势和增产效果，为今后夏玉米改进种植方式提供了依据。     

间作与清种玉米农艺性状及产量的比较研究

以清种玉米为对照,设计玉米/大豆4∶2间作,在间作区内实行3年轮作处理,对玉米的农艺性状、产量及产量因素进行研究。结果表明,生长前期间作玉米株高和叶面积高于清种,后期间作相对较低,差异不显著。间作条件下,玉米根系总长、表面积、体积均高于清种,差异极显著。产量构成因素中,间作玉米穗长和行粒数均高于清种,差异显著;穂粗、穗行数和百粒重差异不显著。单纯比较玉米产量,处理间无显著差异;间作的单位面积子粒总产量明显高于对照。     

稻田春玉米秸秆还田对晚稻和土壤肥力的效应

为探讨玉米秸秆对稻田土壤肥力及晚稻产量的影响，2001～2002年在岳阳进行了玉米秸秆还田试验。设2种玉米秸秆还田量水平即100％和50％，以不还田为对照。两年研究表明：(1)在稻田环境下，玉米秸秆易于腐解；(2)玉米秸秆还田后，土壤有机质及全量N，P，K含量均呈小幅度下降，速效N，P含量下降幅度较大．而速效K增加；(3)玉米秸秆还田对晚稻有较好的增产效果．     

Multifunctionality of paddy fields in Taiwan

Paddy rice is the staple food in Taiwan, where rice farming always plays an important role in agricultural activities. The paddy fields and irrigation activities hold diversified functions, such as production, eco-environmental and living-associated functions. This paper is to provide information regarding the potential magnitude and monetary value of seven functions of paddy fields in Taiwan, including flood mitigation, fostering water resources, preventing soil erosion, purifying water, cooling air temperature, refreshing atmosphere and recreation. For quantification of the above values, replacement cost method (RCM), contingent valuation method (CVM), and the travel cost method (TCM) are adopted. In addition, the ratio of monetary value and their rice production commodity value (R) was also estimated. The results indicated that the flood mitigation function had a monetary value of US$ 389 million each year, and the ratio to the rice production value R was estimated at 37%. Water resource fostering function was US$ 501 million and R at 47%; soil erosion reduction function was US$ 433 million and R at 41%; water quality purification function was US$ 3 million and R at 0.3%; cooling air temperature function was US$ 961 million and R at 91%; refreshing air function was US$ 196 million and R at 19%, health and recreation function was US$ 987 million and R at 93%, respectively. Due to the significant importance of these externalities, it is recommended that the government should properly take into account the multifunctionalities in policy making to ensure sustainable development of agriculture.     

稻田甲烷代谢及其对电子受体的响应

稻田是主要的甲烷排放源之一,其代谢过程及减排策略研究日益受到关注。本文综述了稻田甲烷代谢及其对电子受体响应的最新研究进展。结果表明,稻田甲烷代谢过程因环境条件的改变具有明显的变异性;电子受体主要是通过对甲烷产生和氧化的综合影响,最终控制着土壤甲烷排放;施肥和水分管理均会调节电子受体对甲烷代谢过程的影响。     

Infiltration properties of paddy fields under intermittent irrigation

Puddling and recurring intermittent irrigation, common praxis in wet rice cultivation, modify the soil structure and therewith cause a temporal variation of the infiltration properties. This study attempts to evaluate the temporal variation of the infiltration rates of plough pan (vertical infiltration) and paddy fields’ surrounding bunds (bund infiltration) by analyzing (i) the infiltration rate as a function of time, (ii) the relationship between ponding water depth and infiltration rate, and (iii) the influence of cultivation age on vertical water loss and cross-flow through bunds. Two experimental fields with respective cultivation ages of 30 (A) and 7 (B) years were investigated. The results revealed that the time series of vertical infiltration rate (IR _v) was with time consistency and the persistency of the bund infiltration was uncertain. The mean infiltration rate into the plough pan of A and B was 3.34 and 1.01 cm d^?1, respectively. A total water depth of 230 and 85 cm would be, respectively, lost in A and B through the plough pan during rice growing season. The correlation coefficient between ponding water depth and IR _v was ?0.48 and ?0.81 in A and B, respectively, demonstrating that the dynamic IR _v in the old paddy field was less affected by the drying and wetting cycles. It is concluded that rice paddies which have been taken into cultivation since only a few decades may contribute to water losses. Maintenance of equilibrium condition between ponding and drying stages and careful preparation of bunds may reduce water loss.     

Comparison of evapotranspiration measurements between eddy covariance and lysimeters in paddy fields under alternate wetting and drying irrigation

Paddy and Water Environment - Evapotranspiration from paddy fields under alternate wetting and drying (AWD) irrigation was measured using lysimeters (ETL) and eddy covariance (ETec) during the late...     

Spatial variation of infiltration rate and compactness in paddy fields

Percolation loss of water in rice fields is a major cause of low water use efficiency. Variation of infiltration rate and soil compactness in four paddy fields (with clay, silty clay, clay loam, and loam textures) was investigated in northern Iran. In each field, in longitudinal and transverse directions, points located 0.5, 2.5, 6.5, 12.5, … m from the bunds were selected and water infiltration rate and resistance to penetration of a pocket penetrometer were measured. The results showed that in clay soil, average final infiltration rate (f _c) in longitudinal direction, transverse direction, and center of the field was 0.216, 0.136, and 0.08 cm day⁻¹, respectively. The f _c for loamy soil was 2.77, 2.32, and 0.409 cm day⁻¹, respectively. Similar differences were observed in the other two soil textures. In general, effect of direction of the field for measuring infiltration rate was not statistically significant. Loam and clay loam soils, with resistance to penetration of 0.37 and 0.33 kg cm⁻², were not significantly different. But, clay and silty clay soils with resistance to penetration of 0.25 and 0.14 kg cm⁻² were significantly different (P < 0.05). Resistance to penetration of the penetrometer was not affected significantly (P < 0.05) by direction of measuring this parameter in the field. The conclusion is that if measured soil physical properties in a paddy field are going to be representative of the whole field, they should be measured at different locations, especially near the bunds. Another strategy for obtaining a representative infiltration rate or compactness for a paddy field is uniform puddling of the field.     

A preliminary investigation for Cu distribution in paddy soil and rice plants in contaminated paddy fields

Paddy and Water Environment - The soil sample of a paddy field was found to be contaminated by copper (Cu). The application of wastewater as the nitrogen fertilizer was identified as the cause in...     

宁远县中低产稻田工程改良治理研究

1999～2000年．对宁远县刘家洞的129hm^2冷浸潜育型低产稻田进行了工程改良。根据本地实际。对工程中的沟渠整体布局、沟渠结构及规格进行了具体的设计。通过对比试验分析．改良后的稻田地下水位降低．水温和泥温升高，土壤养分含量增加，早晚稻产量均大幅度提高，取得了明显的治理效果。     

Genetic variation in ZmSO contributes to ABA response and drought tolerance in maize seedlings

Water scarcity impairs maize growth and yield. Identification and deployment of superior droughttolerance alleles is desirable for the genetic improvement of stress tolerance in maize. Our previous study revealed that maize sulfite oxidase(SO) catalyzes the oxidation of sulfite to sulfate and may be involved in drought response. But it was unclear whether the natural variation in Zm SO is directly associated with the drought resistance of maize. In the present study, we showed that Zm SO was ass...