弥雾微喷调控对吐哈盆地葡萄产量和品质的影响

【目的】探索能使葡萄产量与品质达到最佳的微喷+滴灌模式。【方法】以吐哈盆地无核白葡萄为研究对象,通过改变弥雾微喷的喷水时长、喷水周期和微喷布设方式,调控葡萄棚架下微气候环境研究了白葡萄的产量和品质。【结果】当弥雾微喷置于棚架上方时(即WP1处理),弥雾阻碍棚架下的空气与外界交换,使得棚架下的温度增加、湿度降低,其产量较仅滴灌处理的对照(CK)降低11 681.1 kg/hm2,但品质较CK有所提高;弥雾微喷装置于棚架下50 cm处,在葡萄需水关键期(浆果生长期)每天弥雾喷灌1 h,增产效果最为显著,产量达到51 490.95 kg/hm2,且品质得到较为明显的改善;弥雾微喷装置于棚架下其他位置或其他弥雾微喷处理,与CK相比,产量有增有减,但葡萄品质普遍优于CK。【结论】将弥雾微喷装置于棚架下50 cm处并持续每天弥雾微喷1 h能显著提高本地区无核白葡萄的产量和品质。     

用叶绿素测值（SPAD）评估夏玉米氮素状况的实验研究

比较了2000年北京永乐店夏玉米生长过程中，不同水分、氮素处理条件下反映叶片叶绿素含量的SPAD值的变化过程，并且就生育期内平均SPAD值与作物产量，水分生理利用效率之间的关系进行了分析。结果表明，采用叶绿素仪可以较好的对夏玉米生长过程中作物氮素状况对生长的影响进行评价和预测。     

用叶绿素测值(SPAD)评估夏玉米氮素状况的实验研究

比较了 2 0 0 0年北京永乐店夏玉米生长过程中 ,不同水分、氮素处理条件下反映叶片叶绿素含量的SPAD值的变化过程 ,并且就生育期内平均 SPAD值与作物产量 ,水分生理利用效率之间的关系进行了分析。结果表明 ,采用叶绿素仪可以较好的对夏玉米生长过程中作物氮素状况对生长的影响进行评价和预测。     

微喷对葡萄园温、湿度及产量的影响研究

试验于2012-2014年在吐鲁番进行,通过监测各微喷弥雾调控处理下温度、湿度、果粒体积等指标变化情况,分析微喷弥雾调控对棚架下微气候的影响及对果粒和产量的影响。分析显示:在整个微喷弥雾调控期间,多年平均温度和湿度增量为-2.01℃和9.62%。在果粒上,微喷处理的平均果粒体积增量在2012-2014年的试验中分别比对照处理高3.5、4.4和2.9 cm~3,平均增长速率比对照处理高0.12 cm~3/d。在产量上,微喷处理平均产量在2012-2014年中分别比对照处理高2 627.22、1 295.46和3 733.31 kg/hm~2。说明在滴灌的基础上采用每天喷水1 h的弥雾调控灌溉,使棚架下平均温度在26～29℃、湿度在57%～59%时,可明显增大葡萄果实体积,提高果粒增长速率和葡萄产量。结果表明通过微喷弥雾调控,能够改变棚架下微气候,改善葡萄生长环境,从而促进葡萄果实生长,对葡萄增产起到了一定的作用。该研究为合理调控葡萄园微气候环境提供数据支撑,对提高葡萄品质产量,保障我国重要葡萄基地生产的可持续发展具有重要的现实意义。     

弥雾微喷对葡萄光合特性、产量及品质的影响

为研究滴灌+冠层弥雾微喷(降温增湿措施)模式对葡萄光合特性,生理指标及产量品质的影响,试验设定微喷处理(WP1,WP2与WP3)与对照处理(CK)4个处理,在果粒膨大期测定不同处理的光合特性,果粒体积,产量与品质等数据结果显示:微喷处理胞间CO₂浓度日变化幅度均低于对照处理,微喷处理中WP1处理的胞间CO₂浓度最低;各处理的净光合速率均呈现“M”变化规律,在14:00出现“午休”现象,但微喷处理比对照处理“午休”时长较短,且WP1处理在14:00净光合速率降低幅度较小,各处理果粒体积与增长速率大小依次为WP1,WP2,WP3,CK,各处理的果粒体积增长速率均在7月15日达到最大.使用熵值法对各处理的产量与品质进行评价,各处理得分大小依次为WP1,WP2,CK,WP3.说明每日恰当的微喷处理可以显著提高葡萄净光合速率,果粒体积与果粒体积增长速率,产量与品质,但当微喷时间较长时也会影响葡萄产量与品质,因此以微喷1 h/d为最优.     

水肥调控对水稻叶片SPAD值与产量的影响

以鄱阳湖流域典型稻田为研究对象,以"陆两优996"早稻为试材,采用多因素随机区组设计,研究了不同灌溉模式、施氮水平、追肥方式下水稻叶片SPAD值随生育进程的动态变化特征,分析了水氮耦合对叶片SPAD值和产量的交互作用以及水稻各生育期SPAD值与产量的关系,阐明了灌溉、施肥及追肥对水稻SPAD值和产量的影响机制。结果表明:灌溉模式和追肥方式对SPAD值的影响体现在生殖生长阶段,施氮量则体现在作物全生育期。施氮能显著提高SPAD值和产量,但氮肥对产量的贡献表现出边际效应。三次施肥方式能明显延缓SPAD值的下降,提高作物产量。灌溉模式、施氮量和追肥方式之间的交互作用不显著。提高乳熟期叶片叶绿素含量是水稻增产稳产的有效手段,从节水减排增产的角度,最优田间管理措施为W_1N_2F_2且维持乳熟期叶片SPAD值在37～40之间。     

基于高光谱的甜菜SPAD值估算研究

叶绿素作为植物体内参与光合作用的重要色素,其含量对作物生长状况、产量和品质有很大影响。为此,利用野外便携式ASD光谱仪,实测了田间甜菜冠层光谱数据,且用SPAD-502叶绿素仪测定叶片SPAD值。基于原始光谱和一阶导数光谱与SPAD值相关性,选取植被指数和波段深度信息建立SPAD值预测模型,并用对照田试验数据对模型进行验证。通过对比植被指数建立的回归模型及波段深度分析,结合多元逐步回归建立的估算模型可知,波段深度比(BDR)结合SMLR建立的估算模型验证结果最好(RMSE=2.54,RE=4.5%)。研究结果表明:导数处理能提高光谱数据与SPAD值相关系数,波段深度信息结合多元逐步回归相比植被指数能提高SPAD值估算精度。     

水肥耦合对南疆滴灌核桃树生长指标和产量的影响

以7年生的新温“185”为供试材料,通过大田水肥试验,设置不同的水肥正交试验,研究水肥耦合对核桃生长指标和产量的影响,结果表明:核桃叶绿素生育期内大致呈现单峰变化,同一生育期内,在灌水量相同的条件下,随着肥料施入量增大,叶片SPAD值的含量先增大后减小;在施肥量相同的条件下,随着灌水量的增大,叶片SPAD的变化同上;水肥耦合对核桃果实体积的影响显著,核桃体积最大出现在M-M处理,在此基础上再增加肥或者再增加水,都不利于核桃的生长;在产量方面,产量最大出现在H-H处理,最大产量为2 898.75 kg/hm2;增加施肥量,可以提高核桃果实的品质,但过度施肥会导致品质下降和肥料利用率降低。     

基于SPAD的水稻氮素含量测量指标及模型研究

叶绿素相对含量(SPAD)与水稻氮素含量有较好的相关性,但田间叶片的SPAD值测量影响因素较多。本文分析了在不同生长期,不同氮肥胁迫下水稻植株的氮素敏感叶片的叶绿素值的测量影响因素以及随氮素水平变化规律,构建最佳水稻氮素测量指标,并建立叶绿素值与水稻氮素含量检测模型。研究成果可为建立水稻信息专家库及水稻在线施肥系统提供决策依据。     

微喷条件下葡萄叶绿素质量比及荧光参数变化特征

为研究极端干旱区葡萄微喷条件下叶绿素质量比及荧光动力学参数的变化特征,通过对葡萄各生育期叶绿素质量比和叶绿素荧光的测定,分析了微喷条件下不同处理的叶绿素荧光的日变化特征、叶绿素质量比变化及叶绿素质量比与荧光参数的相关性.结果显示:葡萄在坐果期、果实膨大期和果实成熟期的叶绿素质量比(Chl)及荧光参数差异具有统计学意义,Chl和F_v/F_m的变异系数均较小,分别为0.013~0.017和0.009~0.010,F_v/F_o的变异系数最大,为0.026~0.029;在叶绿素与荧光参数的关系上,F_v与F_o,F_m,F_v/F_m,F_v/F_o和F_v/F_m与F_v/F_o呈显著正相关,相关系数为0.157~0.999.F_o/F_m与F_m,F_v,F_v/F_o,F_v/F_m均呈负相关,相关系数为-0.143~0.992;随着喷水周期增大,F_v/F_m和F_v/F_o的实测值降低明显,表明适宜的喷水时长和周期可改善葡萄的叶绿素荧光特性,从而准确反映水分胁迫效应.     

Prediction of Kernel and Bulk Volume of Wheat and Canola during Adsorption and Desorption

Information don the shrinkage of grain both in bulk and as individual kernels is important in postharvest processing of these materials. The mass and volume of samples of wheat and canola seeds exposed either to humid or dry air were measured during adsorption or desorption cycles. When the grains were exposed to 90% r.h. at 40°C, the bulk density of wheat decreased almost linearly from 790 to 686 kg/m³as the kernel moisture content increased from 8% to 22% w.b. The bulk density of canola descreased by 11 kg/m³, from 672 to 661 kg/m³as the kernel moisture content increased from 5% to 19% w.b. The laws of mixtures were used to develop the following equations to predict grain kernel (v_k)and grain bulk volume (v_b)respectively as functions of moisture adsorption or desorption:v_k/v_k0=[1-M₀/1+(γ-1)M₀] [1+(γ-1)M/1-M]andv_b/v_b0={[1-(M₀-M)][1+(γ-1)M]/[1+(γ-1)M₀]} (1-ϵ₀)/(1-ϵ)wherev_kandv_k0are the kernel volumes,v_bandv_b0are the bulk porosities at the kernel moisture contents ofMandM₀respectively;γis the dry kernel density and is assumed to be a constant for each grain. Compared with experimental data, the kernel volumes of both wheat and canola, adequately predicted by the first equation. The second equation gave an adequate prediction of the bulk volume of canola by assumingϵ= ϵ₀,but not for wheat unlessϵwas expressed as a polynomial function of kernel moisture content.     

拖拉机深松机组匹配田间试验方法探讨及测试

针对目前我国深松作业机组匹配田间试验测试方法缺失的问题,分别从主要影响深松机组作业性能的6个方面进行田间试验方法简单探讨,并以某型拖拉机为例对该试验方法进行了验证和对该拖拉机深松机组性能进行了测试,为广大农机具工作者进行拖拉机深松机组匹配田间试验测试提供方法参考。     

Combined effects of KNO3 and salinity on yield and chemical composition of lettuce and Chinese cabbage

Summary The effect of N and K nutrition on the salt tolerance of lettuce (Lactuca saliva L. cv. Saunas) and Chinese cabbage (Brassica campestris L., Pekinensis cv. Kazumi) was evaluated in three greenhouse experiments under a controlled aero-hydroponic system of cultivation. Three levels of KNO₃ (1, 5 and 10 mM) were tested in all the experiments with rapidly circulated saline and nonsaline nutrient solutions. Two experiments, carried out between January and March 1989, with lettuce (Exp. I) and Chinese cabbage plants (Exp. III), consisted of two salinity levels, EC = 1.75 and 6.0 dS m^–1, the former representing a nonsaline nutrient solution. In the third experiment with lettuce (Exp. II., conducted between March and May 1989), three saline nutrient solutions having EC levels of 4.7, 7.75 and 10.75 dS m^–1 were compared to the nonsaline solution. The nutrient solutions were salinized with NaCl and CaCl₂, in a 4:1 molar ratio. The highest yields of fresh weight of both crops were obtained from the 5 mM KNO₃ under both saline and non-saline conditions. The 10 mM treatment caused yield reduction in Chinese cabbage, probably due to a severe tipburn disorder. The relatively high fresh weight yield obtained at the lowest (1 mM) KNO₃ level can be explained by the positive effect of circulation velocity on nutrient uptake. The threshold salinity damage value for the vegetative yield of lettuce plants fed by 5 or 10 mM KNO₃ was approximately 5 dSm^–1 and the yield decreased by 6.5% per unit dS m^–1 above the threshold. No yield improvement due to the addition of KNO₃ occurred under highly saline conditions (Exp. II). The fresh weight of Chinese cabbage obtained from the saline 1 and 5 mM KNO₃ treatments was approximately 15% lower than the non-saline-treatment (Exp. III). Salinity increased tipburn and the effect was not altered by the addition of KNO₃. No significant interaction between nutrition (KNO₃ level) and salinity was found. The application of salts increased the concentration of Na and Cl in plant tissue and reduced the levels of N and K; the opposite occurred in plants fed by the medium and high levels of KNO₃.Contribution from Institute of Soils and Water, ARO, Volcani Center, PO Box 6, Bet Dagan 50250, Israel. No. 3092-E 1990 series     

Effects of different irrigation programs on flower and capsule numbers and shedding percentage of sesame

Irrigation is of great importance to sesame production in Mediterranean-type environments due to positive effect on flower and capsule numbers. Water stress limits sesame growth and development. The objective of this study was to determine the effects of different irrigation programs on flower and capsule numbers, shedding percentage, and yield of sesame. The amount of water used was based on free surface evaporation from a screened class-A pan. Irrigation treatments consisted of three different irrigation intervals (I₁: 7-day; I₂: 14-day; I₃: 21-day), four plant-pan coefficients (K_cp1: 0.60; K_cp2: 0.80; K_cp3: 1.00 and K_cp4: 1.20). The first irrigation was carried out when the available water was at 40% level in the 90 cm of the soil profile. The results revealed significant linear relationships among the irrigation water, water consumption and total number of flower per plant. On the other hand, the highest total number of flower per plant and the highest shedding percentage were obtained from 7-day intervals. Irrigation interval-irrigation amount interaction was significant for the number of sound capsule per plant. The highest number of sound capsule was obtained from K_cp3 treatment at I₁ irrigation interval. Therefore, sesame yield increased by increasing the capsule number.     

Comparative affects of blending,intera/inter-seasonal cyclic uses of alkali and good quality waters on soil properties and yields of paddy and wheat

Degradation of soils irrigated with the ground waters having residual alkalinity constitutes a major threat to irrigated agriculture in semi-arid parts especially the South Asia. Paddy–wheat has come to stay as the major crop rotation in the afflicted areas, which is either irrigated solely with alkali waters (AW) or combined with good quality water supplies through canal networks. Therefore, to develop appropriate conjunctive use strategies for the latter situations, response of paddy and wheat was evaluated to the combined use of a good quality water (GW, EC_iw 0.5, RSC nil) and that having residual alkalinity (AW, EC_w 2.3 dS m⁻¹, RSC 11.3 mequiv L⁻¹, SAR_w 15 mmol L^0.5) for 6 years (1997–2003) in lysimeters (2.0 m deep, 0.9 m i.d., with drainage outlets at the bottom) filled in with a sandy loam soil (pH 7.8, ESP 5.3). Increase in soil pH (8.71), salinity (3.8 dS m⁻¹) and sodicity (ESP 27.3) as a consequence of irrigation with alkali water markedly affected the yields of both the crops. The sustainability yield index (SYI) was 0.522 and 0.793 for paddy and wheat, respectively, indicating the sensitivity of the former to the use of alkali water. Keeping the AW input to be similar through irrigations, the SYI for paddy with blending of GW and AW in the ratio of 2:1, 1:1 and 1:2 was 0.732, 0.708 and 0.678, respectively, when compared with 0.751, 0.729 and 0.701 under intera-seasonal cyclic uses. Similarly, the SYI of wheat ranged between 0.821–0.907 and 0.853–0.949 with blending and cyclic uses of the two waters, indicating thereby a yield advantage with the latter. When the two waters were rotated inter-seasonally, the dilution effects of monsoon rains helped to induce greater use of AW for paddy. The overall deterioration in soil properties under different modes was related to proportion of AW applied. It was concluded that the alternating good quality and alkali waters could be a better way to alleviate sodicity problems caused with the use of alkali water alone.     

Yield and quality of melon grown under different irrigation and nitrogen rates

During 2 years, a melon crop (Cucumis melo L. cv. Sancho) was grown under field conditions to investigate the effects of different nitrogen (N) and irrigation (I) levels on fruit yield, fruit quality, irrigation water use efficiency (IWUE) and nitrogen applied efficiency (NAE). The statistical design was a split-plot with four replications, where irrigation was the main factor of variation and N was the secondary factor. In 2005, irrigation treatments consisted of applying daily a moderate water stress equivalent to 75% of ETc (crop evapotranspiration), a 100% ETc control and an excess irrigation of 125% ETc (designated as I₇₅, I₁₀₀ and I₁₂₅), while the N treatments were 30, 85, 112 and 139 kg N ha⁻¹ (designated as N₃₀, N₈₅, N₁₁₂ and N₁₃₉). In 2006, both the irrigation and N treatments applied were: 60, 100 and 140% ETc (I₆₀, I₁₀₀ and I₁₄₀) and 93, 243 and 393 kg N ha⁻¹ (N₉₃, N₂₄₃ and N₃₉₃). Moderate water stress did not reduce melon yield and high IWUE was obtained. Under severe deficit irrigation, the yield was reduced by 22% mainly due to decrease fruit weight. The relative yield (yield/maximum yield) was higher than 95% when the irrigation depth applied was in the range of 87-136% ETc. In 2006, the interaction between irrigation and N was significant for yield, fruit weight and IWUE. The best yield, 41.3 Mg ha⁻¹, was obtained with 100% ETc at N₉₃. The flesh firmness and the placenta and seeds weight increased when the irrigation level was reduced by 60% ETc. The highest NAE was obtained with quantities of water close to 100% ETc and increased as the N level was reduced. The highest IWUE was obtained with applications close to 90 kg N ha⁻¹. The I₂₄₃ and I₃₉₃ treatments produced inferior fruits due to higher skin ratios and lower flesh ratios. These results suggest that it is possible to apply moderate deficit irrigation, around 90% ETc, and reduce nitrogen input to 90 kg ha⁻¹ without lessening quality and yields.     

畜禽粪污综合利用对土壤肥力和持续农业的影响分析

文章围绕畜禽粪污治理现状,深入探讨畜禽粪污综合开发利用对农业土壤肥力持续发展的意义,并针对不同时期,相应的粪污利用策略对现代绿色农业持续发展的影响进行了分析。     

萃取浓缩沼液对尖孢镰刀菌和腐皮镰孢菌抑制效果的影响研究

为了研究不同有机溶剂萃取浓缩沼液对尖孢镰刀菌(Fusariumoxysporum)和腐皮镰孢菌(Fusariumsolani)抑制效果的影响,该实验采用6种常见的有机溶剂(乙酸乙酯、苯、乙醚、甲苯、环己烷、石油醚)对已经去除80%水分的沼液浓缩液进行萃取后再浓缩,将最终的萃取浓缩物进行抑菌试验。结果显示:6种有机溶剂萃取得到的萃取浓缩物都对尖孢镰刀菌和腐皮镰孢菌有抑制作用,且萃取浓缩物的抑制效果强于浓缩液、原沼液和萃取后剩余浓缩液的抑制效果。该实验可为沼液防治三七根腐病的利用奠定基础和依据。     

Effect of cyclic use and blending of alkali and good quality waters on soil properties,yield and quality of potato,sunflower and Sesbania

Degradation of soils through the use of alkali waters constitutes a major threat to irrigated agriculture especially for the cultivation of sodicity sensitive crops. The response of potato (Solanum tuberosum), sunflower (Helianthus annus) and Sesbania (Sesbania sesban) green manure to the combined use of a good quality canal water (CW, ECcw 1.1 dS/m, RSC nil, SAR 1.8) and an alkali water (AW, ECaw 3.6 dS/m, RSC 15.8 me/L, SAR 12.4) was evaluated for 5 years (1998–2003) on a well drained sandy loam soil (ECe 2.5 dS/m, pH 7.9, exchangeable sodium percentage, ESP 5.3). Increase in soil pH (8.9–9.1), salinity (4.7–5.1 dS/m) and sodicity (ESP 25–41) as a consequence of irrigation with alkali water affected the growth and yields of all the crops. The sustainability yield index (SYI) when irrigated with AW was 0.063 and 0.133 for potato and sunflower, respectively, indicating that these crops should not be irrigated with such high alkalinity waters. Cyclic use treatments included alternating irrigations with CW and AW, with CW to start with (1CW:1AW), alternating two irrigations each with CW and AW and applying CW to start with (2CW:2AW), alternating two irrigations each with CW and AW and applying AW to start with (2AW:2CW), four irrigations with AW to start with and followed by two with CW (4AW:2CW) and crop-wise alternations of CW and AW, with application of CW to potato and AW to sunflower (CWp:AWs). The SYI of potato improved to 0.703, 0.642, 0.442 and 0.579, respectively with the cyclic 1CW:1AW, 2CW:2AW, 2AW:2CW and CWp:AWs treatments. The values of SYI were 0.633 and 0.415 for potato when irrigated with blends of CW and AW in the ratio 2:1(2CW:1AW) and 1:2 (1CW:2AW), respectively. Similarly, the SYI for sunflower ranged between 0.481–0.736 and 0.512–0.592 for cyclic use and blending but was reduced to 0.394 with 4AW:2CW in cyclic use mode. When averaged for 5 years, the relative yields (compared to CW) ranged between 65–85 and 61–94% for cyclic use in potato and sunflower, respectively. However, the values ranged between 66–83 and 71–81% for blended waters. Considerable deterioration in produce quality was observed in terms of potato grade and weight loss on storage as well as the smaller seeds along and lower oil content in the case of sunflower. The overall deterioration in soil properties under different modes was related to the proportions of AW applied. Computations further indicated that with a similar proportion of CW and AW, cyclic application CW during the initial stages would minimise the adverse effects of alkali water.     

Effects of salinity and fertigation practice on cotton yield and N recovery

The purpose of optimal water and nutrient management is to maximize water and fertilizer use efficiency and crop production, and to minimize groundwater pollution. In this study, field experiments were conducted to investigate the effect of soil salinity and N fertigation strategy on plant growth, N uptake, as well as plant and soil ¹⁵N recovery. The experimental design was a 3 × 3 factorial with three soil salinity levels (2.5, 6.3, and 10.8 dS m⁻¹) and three N fertigation strategies (N applied at the beginning, end, and in the middle of an irrigation cycle). Seed cotton yield, dry matter, N uptake, and plant ¹⁵N recovery significantly increased as soil salinity level increased from 2.5 to 6.3 dS m⁻¹, but they decreased markedly at higher soil salinity of 10.8 dS m⁻¹. Soil ¹⁵N recovery was higher under soil salinity of 10.8 dS m⁻¹ than those under soil salinity of 6.3 dS m⁻¹, but was not significantly different from that under soil salinity of 2.5 dS m⁻¹. The fertigation strategy that nitrogen applied at the beginning of an irrigation cycle had the highest seed cotton yield and plant ¹⁵N recovery, but showed higher potential loss of fertilizer N from the root zone. While the fertigation strategy of applying N at the end of an irrigation cycle tended to avoid potential N loss from the root zone, it had the lowest cotton yield and nitrogen use efficiency. Total ¹⁵N recovery was not significantly affected by soil salinity, fertigation strategy, and their interaction. These results suggest that applying nitrogen at the beginning of an irrigation cycle has an advantage on promoting yield and fertilizer use efficiency, therefore, is an agronomically efficient way to provide cotton with fertilizer N under the given production conditions.