引进大果沙棘新品种实生子代性状分离与选优

对设置于黑龙江省绥棱县的俄罗斯大果沙棘优良引进品种特丰1号和特丰2号实生子代选种群体表型性状指标分化规律进行了分析,以揭示俄罗斯大果沙棘品种实生子代性状分离规律,为大果沙棘良种实生选种提供理论基础,并选育沙棘优良新品种,得到几点主要结论:(1)引进品种实生子代在我国东北具有良好的生长适应性,生长指标有较大幅度的分化;各表型指标中单株产量及棘刺数变异程度较大,表明子代群体具备良好的经济性状选种潜力;引进品种实生子代群体雌雄分化性状符合孟德尔自由组合规律。(2)从引进品种实生子代群体中初选出的55个单株在果实百果质量这一重要性状上表现优异,一些单株果实产量可达10000kg/hm2,表现出了良好的经济潜能;55个初选单株果实VC、VE、水解总黄酮含量均有明显的分化,且实生子代初选单株果实黄酮组分中以异鼠李素含量最高,与中蒙沙棘杂交子代不同。(3)在以百果重及单株产量为经济性综合评价指标基础上,筛选出3个高产、高VC型沙棘优良单株、5个高产、高VE型沙棘优良单株、3个高产、高黄酮型沙棘优良单株。     

干旱胁迫对不同种源沙棘产量因子影响分析

为了探讨、揭示干旱胁迫对沙棘生育与产量形成因子间的关系。本文采用田间调查与室内实验分析相结合。结果表明沙棘单株生育与产量关系受干旱胁迫影响最大,造成植株生长势衰弱与减产。沙棘产量的形成,决定于植株生长势、水分利用效率、根系贮水能力、果枝数、座果率。     

半干旱黄土丘陵区沙棘优良品种引种栽培试验研究

1994-2003年在黄土高原半干旱区的陕西吴旗县、安塞县进行中国沙棘优良类型和俄罗斯优良沙棘品种引种试验,采用家系选择法初步筛选出5个中国沙棘生态经济型优良单株,对3个俄罗斯良种沙棘的生长适应性经济性状进行了评价。前者生长迅速、树冠好、根系发达、郁闭快、水土保持效益好,果实较大、单株产量较高、Vc和含油量较高,适于在黄土丘陵区种植;后者经济性状较好,果实大、无刺或少刺,但适应性较中国沙棘差。     

榆林市大果沙棘的引种效果

为了解决中国沙棘果实小、产量低、棘刺多等问题,榆林市林业站先后引进大果沙棘品种16个。栽培试验结果表明,大部分品种在引入后生长良好、繁殖正常,没有发现早衰现象或严重的病虫危害,同时保持了果实大、产量高、无刺或刺少等优良特性。其中,果实横径5．06mm～6．51mm、纵径7．46mm～10．33mm,向阳、齐棘1号等9个品种的果实产量达到10000kg／hm2以上,单株平均拥有克隆子株2．0～5．0株,混合种子的生活力达95％。     

水稻穗部性状与产量的关系

水稻穗部性状在产量结构中起到重要作用,对其与稻米品质、产量的相关性进行研究.结果表明,穗部性状与产量相关密切,品种间差异较大.水稻穗部性状的品种间差异较大,不同品种对产量产生较大影响的产量构成因素主要是单株有效穗数和穗粒数,结实率与千粒重相对比较稳定.在穗部性状中,二次枝梗的影响较大;不同品种水稻存在着穗粒矛盾,必须协调二者关系.     

智利的沙棘引种栽培试验初报

智利1994年引种了德国3个品种、俄罗斯6个品种,分别种植在不同纬度地区,并对其生长情况、 果实产量、产生的根瘤进行了观测,结果表明:在同一地区德国沙棘比俄罗斯沙棘生长良好,果实产量高。 试验证明德国沙棘在南纬53°的地区生长良好。     

良种沙棘种植园高效栽培试验研究

通过沙棘品种、栽培密度、施肥、灌水等项试验研究。总结分析各试验因子对沙棘生长发育以及产量的影响,提出良种选择、授粉树配置、栽植密度、肥水管理、整形修剪、病虫害防治等丰产栽培技术措施。     

沙棘亚种间杂交子代优良单株叶片黄酮含量分析

连续3次从以蒙古沙棘亚种优良品种为母本的中蒙沙棘杂交试验中选出的50余个杂种单株叶片黄酮质量及其组分质量的分析,发现3点主要结论：（1）不同优良杂种单株总黄酮质量差异非常明显。变化范围在140．7—2661．7mg／100g之间,且相同母本或同一单株子代优株之间的叶片总黄酮质量的差异也是非常明显的。（2）杂种单株叶片黄酮的组分主要以槲皮素为主;（3）优良杂种单株果实及种子的总黄酮质量均要明显低于叶片的总黄酮质量,而大多数优良杂种单株种子的总黄酮质量则要高于果实,优良沙棘杂种叶片黄酮的提取应是沙棘最为有效的途径。     

不同磷效率基因型大豆产量构成因素及籽粒产量通径

以30个不同磷效率基因型大豆品种（系）为材料,研究了不同磷水平条件下3种大豆的产量构成因素变化及其对籽粒产量通径。结果表明,在施磷肥条件下,磷低效基因型品种和中间型品种的产量高于磷高效基因型品种;而不施磷肥条件下,磷高效基因型品种的产量显著高于磷低效基因型品种和中间型品种。在本试验条件下,单株荚数、单株粒数和产量之间存在正相关关系,但百粒质量与产量之间存在负相关关系。通径分析表明,所有品种产量3因素对产量都有正向效应,其中单株荚数和单株粒数对产量的贡献最大;不同磷效率基因型品种产量构成因素对产量的间接通径系数既有负值也有正值,说明品种产量3因素间存在相互制约或相互促进的关系。总之,在低等肥力下,大豆的高产栽培选择磷高效基因型品种较为稳定;在高肥条件下,磷低效基因型品种则具有更高产量潜力,是今后超高产大豆育种值得关注的类型。      

灌溉对中国沙棘雌株叶、果生长发育及产量的影响分析

本文对中国沙棘雌株进行灌溉试验,试验结果表明：灌溉对中国沙棘雌株无性系的叶、果生长发育及果实产量影响显著,非充分灌溉可提高果实产量约20％。     

降水、灌溉和品种对玉米产量和水分利用效率的影响

8年田间试验结果表明,玉米产量明显受降水和灌溉的影响。玉米苗期灌溉最为关键,是保证高产的基础。在只灌溉苗水而没有其他灌溉条件下,夏玉米产量与7、8月份降水密切相关,而与生长季节的降水总量关系不明显。除了极干旱年份(季节降雨量小于200 mm)外,随着灌溉量增加,玉米水分利用效率(WUE)降低。玉米最优灌溉制度为:干旱年份,除了苗期的1次灌溉外,在拔节和扬花期分别实施2次灌溉;常年和湿润年份,除了出苗水外,在抽穗到扬花期的8月初实施1次灌溉。3年的田间试验结果表明,当地种植的不同玉米品种之间产量最大相差20%,水分利用效率差异在12%~19%。因此,将适宜的品种与优化的灌溉制度相结合,是提高华北平原夏玉米产量和水分利用效率的有效途径。     

降雨年型对南通棉花生产的影响

通过对南通棉区降雨量和棉花产量的长系列资料的整理分析，揭示棉花生育期各时段的雨量与产量的关系，运用统计学的聚类分析方法，将生育期的雨量划分为特征鲜明的若干年型．用水量平衡方法进一步分析降雨年型对棉花生产的影响，最后建立统计模型，进行降雨（丰、歉）年型的预测。     

Climate change impacts on wheat production in a Mediterranean environment in Western Australia

The environment in which crops will be grown in the future will change. CO₂ concentrations [CO₂] and temperatures (T) will probably increase and a decline of winter rainfall is predicted for south-west Australia. To be able to adapt crop systems to a changing climate it is important to know how different aspects of climate change affect agricultural production and how they interact. In a full factorial design we studied how higher T (2, 4 and 6 °C) elevated [CO₂] (525 and 700 ppm) and five different rainfall scenarios affected wheat yield and grain protein. Effects of climate change were simulated with the Agricultural Production Systems Simulator (APSIM-Nwheat) using transformed historic weather data. Fifty years of yield and grain protein concentrations were simulated for three soil types at different locations on a north–south transect within the wheatbelt of south-west Australia.

Simulation results showed that there were complex interactions between different aspects of climate change on crop systems. Effects of higher temperatures, elevated [CO₂] and changed rainfall were in general not linear and differed significantly between soil types and location. Higher [CO₂] increased yield especially at drier sites while higher temperatures had a positive effect in the cooler and wetter southern part of the region. The main difference between soil types was that heavier clay soils are most vulnerable to reduced rainfall while sandy soils were more vulnerable to higher temperatures. Elevated [CO₂] reduced grain protein concentration and lower rainfall increased protein levels at all sites. Higher temperatures could both increase and decrease protein concentrations.

In the southern, higher rainfall part of south-western Australia, yield and gross margin will increase for all likely future climate scenarios. In the drier part of the region, negative effects of 15% reduced rainfall can be compensated for by a 2 °C increase in temperature and 50% higher [CO₂] concentrations. However due to the non-linearity of climate change effects a 30% reduction in rainfall cannot be compensated for by higher temperatures and [CO₂].     

Water use,water-use efficiency and yield of dryland chickpea as influenced by P fertilization,stored soil water and crop season rainfall

Dryland chickpea is grown on stored water in the soil profile and with limited crop season rainfall (CSR). In a field experiment, carried out for 3 years on silty loam soil, water extraction pattern, water use and its efficiency by chickpea in relation to P application, stored soil water and crop season rainfall have been investigated. Stored soil water varied from 182 to 246 mm in a meter profile and the CSR varied from 72 to 184 mm.Response of P application increased with increasing initial water storage in the soil profile. The first 60–100 days of crop growth appeared to be the most critical. Water stress during this period severely affected the yield. Rainfall after 100 days did not appear to have been fully utilized by the crop, especially when the crop had already suffered from water stress between 60 and 100 days. Compared with the control, P application increased yield, water use and water-use efficiency. Soil water depletion was 25% greater for the fertilized crop than for the unfertilized crop.     

Alternative cropping strategies for assured and efficient crop production in upland rainfed rice areas of eastern India based on rainfall analysis

The productivity of rice in rainfed upland soils of eastern India is very low (<1 t/ha) and unstable because of erratic monsoon, moisture deficit during dry spells, light textured with less fertile soils and several biological constraints (weeds, pests and diseases). Keeping the urgent need of augmenting the productivity of vast rainfed upland rice ecosystem of eastern India (4.3 million ha), crop diversification technology was generated through on-farm research trials in representative upland rice soils of eastern India after analyzing agro-climatic (rainfall variability, probability and onset of effective monsoon) and edaphic (soil water retention properties) constraints and prospects. Based on rainfall analysis, direct seeded, low water requiring, rice substituted alternative upland crops namely maize, groundnut, pigeonpea, greengram and blackgram (sole or intercropping) was sown in light textured upland rice soils on 24th meteorological weeks (11–17 June) in 3 years 2000–2002 with two to three summer ploughings during pre-monsoon shower (May). Study revealed that in deficit rainfall years (2000 and 2002), when rice yield was affected adversely in light textured upland, higher rice equivalent yield and rain water use efficiency were obtained from groundnut+pigeonpea intercropping followed by sole groundnut and sole pigeonpea. Study also revealed that productivity of rice substituted crops in the same upland did not fluctuate much between rainfall excess (2001) and rainfall deficit years (2002 and 2000). Double cropping in rainfed upland rice soils was also explored through maize–horsegram/sesamum rotation with increased productivity and rainwater use efficiency. The crop diversification technology was found to be very effective for drought mitigation.     

基于Meta分析的中国灌溉冬小麦产量及水分利用效率影响因素研究

【目的】目前针对灌溉冬小麦产量与水分利用效率影响因素的研究大多集中于某一特定区域,研究结果零散,针对上述问题,揭示宏观尺度下灌溉冬小麦产量和水分利用效率的影响因素。【方法】综合已发表的田间试验数据,采用Meta分析方法得出灌溉在不同地区的增产效应和水分效应,在异质性检验的基础上,通过Meta亚组分析探究灌溉定额、降雨量和平均气温等对冬小麦产量和水分利用效率的影响机制。【结果】与生育期不灌溉相比,灌溉使冬小麦总体增产39.34%,水分利用效率提高3.39%;增产率随灌溉定额的增加而增大,增幅最终趋于稳定,水分利用效率随灌溉定额的增加呈先增加后减少的趋势,当灌溉定额>240 mm时,冬小麦相对水分利用效率变化率显著降低11.29%;随着生育期平均温度上升,灌溉冬小麦增产效应显著提高,生育期均温>9℃时,冬小麦增产率高达45.81%;生育期降雨量对灌溉冬小麦产量影响显著,生育期降雨量处于干旱年份时灌溉增产效应最明显,增产率为72.48%。【结论】灌溉定额为60~120 mm更有利于提高冬小麦产量和水分利用效率。     

Irrigation scheduling of cotton in a climate with uncertain rainfall

Summary An investigation was made of the irrigation requirements of cotton grown in a sub-humid environment with significant but highly variable rainfall. In the first year of the study, no additional yield benefits accrued to subsequent irrigations following a pre-emergent irrigation due to above average rainfall (550 mm) throughout the growing season. In the second year a similar rainfall amount (502 mm) fell but significant yield increases to irrigation resulted due to the uneven distribution of the rainfall. The main effect was associated with later rains which influenced the number of bolls set. The maximum amount of water extracted by cotton from a deep grey cracking clay was 178 mm. It was found that 70% of this amount could be depleted before irrigation without loss of yield. Crop evapotranspiration varied from 607 mm with no irrigation after emergence to 775 mm following three irrigations. Irrigation was associated with significant losses from rainfall runoff. Too frequent irrigation creates a risk that soil will be too wet to permit utilisation of natural rainfall. Therefore, the use of soil water information to maximise the interval between irrigation is proposed as a necessary basis for efficient irrigation management.     

Suitability of cotton cultivation in shrink–swell soils in central India

Rainfed cotton farming is a risky enterprise. It has always been a challenge to sustain cotton productivity under rainfed conditions not only in India but also in similar agro-environments elsewhere. The present study is an attempt to find out the most sustainable soil under varying rainfall through crop yield correlation with agro-environment factors, like soil physiographic conditions, growing period rainfall, crop ET and phasic rainfall, by conducting (farmers’) field experiment in a representative catena with four different soil types in central India. Cotton (hybrid-H4) was grown for 5 years; 3 years under normal rainfall, 1 year under excessive rainfall and 1 year under drought conditions. The investigation revealed that in the excess rainfall to drought years, yield fluctuation varied from 2% to 38% over the normal year in shallow soils occurring on a pediment plain to the very deep soils in a valley plain. However, the yield fluctuation in deep Vertisols occurring on lower Piedmont and narrow valley, representing Vertic Haplustepts (P3) and Typic Haplusterts (P4), was 25–38% and 6–25%, respectively. The low yield fluctuation and high yield correlation with agro-environmental factors, observed for P3 soils, suggests the suitability of Vertic Haplustepts (P3) for cotton production under varying rainfall conditions. Cultivating P3 soils for cotton could stabilize the income of cotton farmers and research relating to cotton genotype improvement under rainfed conditions should be carried out to minimize soil effects. The international land evaluation criteria suggested by FAO show that Vertisols (P3 and P4) qualify as a suitable category for cotton production under rainfed conditions. However, the present study indicates that this categorization may need revision in view of the adverse climatic conditions of central India. In order to improve the effectiveness of the FAO’s land evaluation criteria for sub-tropical Vertisols, the study suggests that more emphasis be given to rainfall in the critical growth phases related to crop yield and to soil hydraulic conductivity related to the Ca²⁺/Mg²⁺ ratio in computing land indices, rather than total quantum rainfall during the growing period. Also, too many soil properties are presently considered in the FAO method. A quantum of 250–325 mm rainfall at the square initiation to peak flowering stages was found to influence yield. Under climatic aberration, the high fluctuation of cotton productivity in deep Vertisol (P4) may be minimized by adoption of any soil management technology (e.g. ridges or broad-bed furrow system) that helps in improving internal drainage. It is, therefore, urgent that the Indian Government should enact special legislation or introduce incentives for the Vertisol farmers who mostly use old cultivation practices to adopt such technology on a large scale. A quadratic regression model developed in this study to compute the yield under varying rainfall may help in estimating the economic losses to the farmers and quantifying crop insurance compensation.     

The wheat yields and water-use efficiency in the Loess Plateau: straw mulch and irrigation effects

The yield of spring wheat (Triticum aestivum L.), one of the major crops planted in the Loess Plateau, China, is mainly affected by available water. Straw mulch and irrigation are efficient ways of influencing wheat yield and water-use efficiency. To develop better semiarid crop and water management practices, a 13-year experiment in spring wheat monoculture was conducted at the Dingxi Soil and Water Conservation Institute of the Loess Plateau. The influence of rainfall during the growing season (March–July) on yields of rain-fed wheat was studied for 13 years (1982–1992 and 1997–1998). The influence of straw mulch and irrigation on wheat yield, and water-use efficiency, was studied for 2 years (1997–1998). We found that growing season rainfall had a significant (P < 0.05) influence on biomass and grain yield of spring wheat in rain-fed conditions during the 13 years. Both biomass and grain yield were very low and varied significantly due to the low and significant variability of growing season rainfall. Straw mulch increased wheat yields significantly during both dry (1997) and wet (1998) years. It increased biomass and grain yield by 37 and 52%, respectively, in 1997, and by 20 and 26%, respectively, in 1998. Straw mulch also significantly decreased evapotranspiration (P < 0.05), soil water depletion (P < 0.01), and increased water-use efficiency (P < 0.001). Biomass and grain yield both increased (P < 0.01 orP < 0.001) with increasing irrigation in 1997 and 1998. The three irrigation levels increased the biomass yield from 34 to 66% in 1997, and from 34 to 77% in 1998. The irrigation levels also increased grain yield from 53 to 102% in 1997, and from 22 to 57% in 1998. Water-use efficiency for biomass and grain yield also increased with increasing irrigation. On the other hand, irrigation water-use efficiency for biomass and grain yield decreased with increasing irrigation. The results suggest that higher crop yields in the semiarid Loess Plateau may be achieved by using irrigation, or a proper combination of straw mulch and irrigation.     

微咸水灌溉下土壤水盐动态及对作物产量的影响

华北平原农业灌溉用水非常紧缺,水资源日益缺乏与粮食需求日益增多之间的矛盾尖锐。充分利用微咸水资源是缓解这一矛盾的重要途径之一。该文以中国农业大学曲周试验站1997－2005年冬小麦和夏玉米微咸水灌溉田间长期定位试验为基础,研究了充分淡水、充分淡咸水、关键期淡水、关键期淡咸水和不灌溉等5个处理下土壤饱和电导率和含盐量的动态变化,探讨了微咸水灌溉对冬小麦和夏玉米产量的影响。结果表明：土壤水盐动态呈受灌溉和降雨影响的短期波动和受季节更替影响的长期波动;在正常降雨年份,使用微咸水进行灌溉是可行的,不会导致土壤的次生盐渍化;微咸水灌溉虽然导致冬小麦和夏玉米产量降低10%～15%,但节约淡水资源60%～75%。如果降雨量达到多年平均水平以及微咸水灌溉制度制订合理,微咸水用于冬小麦/玉米田间灌溉前景广阔。