Sweet Sorghum [Sorghum bicolor (L.) Moench] Biomass Production for Biofuel and the Effects of Soil Types and Nitrogen Fertilization

This research aimed to determine the optimum nitrogen fertilization rate on three soils for producing biomass sweet sorghum (Sorghum bicolor cultivar M81E) and corn (Zea mays cultivar P33N58) grain yield and to compare their responses. The research was conducted in Missouri in rotations with soybean, cotton, and corn. Seven rates of nitrogen (N) were applied. Sweet sorghum dry biomass varied between 11 and 27.5 Mg ha^?1) depending on year, soil type, and N rate. Nitrogen fertilization on the silt and sandy loam soils had no effect (P > 0.05) on sweet sorghum yield grown after cotton and soybean. However, yield increased in the clay soil. Corn grain yielded from 1.3 to 12.9 Mg ha^?1, and 179 to 224 kg N ha^?1 was required for maximum yield. Increasing biomass yield required N application on clay but not on silt loam and sandy loam in rotations with soybean or cotton.     

不同种植方式及肥密因素下饲用甜高粱的产量表现

探讨了不同肥密因素下分期青刈、麦茬复种与常规种植饲用杂交甜高梁的产量变化.结果表明,常规种植饲用杂交甜高粱,在25种肥密组合中4个组合效果较好者,产量可达59.6 t/hm2以上;相同肥密条件下分期青刈效果优于常规一次性收获,表现产量高,植株鲜嫩.麦茬复种饲用杂交甜高粱在地处寒地的黑龙江是可行的,其最佳肥密组合产量可以达到31.3样t/hm2,日产鲜草量高于常规种植及分期青刈的最高产量组合,达9.3%和8.3%.黑龙江省小麦种植面积近2.00×105hm2,若进行麦茬复种每年可生产优质鲜饲料达6.00×105t,这即能充分利用寒地有限的光温资源,又可减少水土流失,更利于促进畜牧业的发展.     

Sensitivities of Stress Indicators for Available Soil Water and Its Salinity and for Sorghum Leaf Water Potential under Drip Irrigation

Abstract

The impact of two input amounts, two frequencies, and three salinity levels on the temporal sensitivity of the stress indicators, available soil water (K _W ), its salinity (K _S ), and leaf water potential of sorghum [Sorghum bicolor (L.)] grown in dune sand in a plastic greenhouse were investigated. The K _W for the irrigation input amount equivalent to one‐half of an open pan on a daily basis (EP0.50‐1) ranged from 0.32 to 0.51 compared with 0.51 to 0.98 for the 100% of open‐pan irrigation input on daily basis. The corresponding K _S ranges were 0.50 to 0.98 (EP1.00‐1) and 80 to 0.98 for K _s . The K _W for the three increasing salinity levels (S‐1, S‐2, and S‐3) ranged from 0.68 to 0.96 for S‐1, 0.58 to 0.90 for S‐2, and 0.43 to 0.89 for S‐3, respectively, and from 0.85 to 1.00 for the control. The corresponding K _S ranges were 0.89 to 0.98, 0.70 to 0.96, 0.49 to 0.70, and 1.00 to 1.00, respectively. The LWP ranges for the three salinity levels were ?1.70 to ?0.70 for S‐1, ?2.50 to ?1.20 for S‐2, ?2.90 to ?1.60 for S‐3, and ?0.70 to ?0.20 MPa for the control. The time series statistical parameters mean, median, coefficient of variation (CV), and the 20th percentile values (PC20), assessed to discriminate the temporal sensitivity of the stress indicators indicated that CV and PC20 are equally better than median, which in turn is better than mean. Sorghum grain yield depended on irrigation input amount and schedules, leaf water potential (LWP), and the interaction involving K _W and K _S (R² _adj 0.71 to 0.85). The temporal sensitivity of the stress indicators K _W , K _S , and LWP indicated that EP1.00‐1 provided the least‐risk irrigation option with regard to water and salinity stress in relation to sorghum grain yield.     

Leaf Mineral Composition of Olive Varieties and Their Relation to Yield and Adaptation Ability

The amount of yield and adaptation of a cultivar to a new environment is strongly related to nutrient uptake ability. The aim of this study was to compare nutrient uptake ability of 21 local and/or standard olive varieties grown under Mediterranean climatic conditions. Elemental compositions of olive leaves were determined for two consecutive years. The highest yields were obtained from ‘Gemlik’, ‘Manzanilla’, ‘Memecik’, and ‘Hojiblanca’ varieties. Nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg), and manganese (Mn) content of leaves were comparatively higher in the high-yielding year (2004) whereas iron (Fe) and copper (Cu) contents were lower. Nutrient uptake ability and usage efficiency of olive varieties were different. Mineral composition of leaves was variety dependent and different groups of varieties showed higher leaf concentration for each element. Therefore, it can be concluded that the variation in the nutrient uptake ability may be used as a criterion for adaptation of a variety to a new ecological environment.     

Optimizing Nitrogen Fertilization for Production of White and Orange-Fleshed Sweet Potato in Southeast Nigeria

ABSTRACT

Two field experiments were used in 2005–2006 to study the effects of nitrogen (N) on light interception, weed biomass, and yield of white and orange-fleshed sweet potato varieties in southeastern Nigeria. Treatments comprised four N levels (0, 40, 80, 120 kg N ha^?1) and four varieties of sweet potato (White-fleshed TIS 87/0087 and TIS 8164, orange-fleshed Ex-Igbariam and CIP Tanzania), arranged in randomized complete block design with three replications. Nitrogen application up to 120 kg N ha^?1 increased light interception, leaf area index and shoot dry matter. Regardless of rate, N application reduced weed growth at 12 weeks after planting. On average, the storage root yield increased with N application up to 80 kg N ha^?1 when the background soil N was 0.056% in 2005, but not beyond the rate of 40 kg N ha^?1 when the background N was 0.104% in 2006. The white-fleshed TIS 87/0087 followed by orange-fleshed Ex-Igbariam out-yielded other varieties and intercepted over 70% of the incident radiation.     

不同土壤肥力水平下施氮对甘薯产量与氮肥利用率的影响

为探明不同土壤肥力条件下施用氮肥对甘薯产量和氮肥利用率的影响,选取鲜食型甘薯品种烟薯25号为试验材料,采用大田试验,研究了施氮对不同土壤肥力下甘薯产量及产量构成因素、干物质积累规律和氮肥利用率的影响。结果表明:不施氮条件下,甘薯蔓数、最大蔓长度、叶面积指数和产量均表现为高肥力中肥力低肥力(P0.05)。3种土壤肥力条件下,增施氮肥均能显著增加甘薯蔓数、最大蔓长度和叶面积指数(P0.05),但对最大蔓节间数影响不显著。高肥力、中肥力和低肥力地块分别在施氮量为50,100,150kg/hm~2时获得最高产量,分别较不施氮处理(N0)增产16.06%,29.63%和33.33%。与地力条件无关,增施氮肥均能提高甘薯地上部干物质累积量。中、低土壤肥力条件下,甘薯氮累积量随施氮量增加逐渐增加,而高土壤肥力条件下呈先增加后降低的趋势;高肥力地块氮肥利用率随施氮量增加而逐渐降低,中肥力地块先增加后逐渐降低,在100kg/hm~2时氮肥利用率最高,低肥力地块逐渐增加。综合产量和氮肥利用率,可知高肥力、中肥力和低肥力地块甘薯适宜施氮量分别为50,100,150kg/hm~2。     

减量控释氮肥对大棚甜椒产量及土壤硝态氮、铵态氮分布的影响

采用田间试验方法研究不同控释氮肥施用量对大棚甜椒生长及硝态氮、铵态氮含量分布的影响。结果表明,控释氮肥处理对大棚甜椒的产量、肥料利用率、氮肥农学效率、氮肥偏生产力较常规施肥有不同程度的提高,以RF30处理最佳。各施肥处理均显著增加了土壤全氮、甜椒Vc、可溶性糖、硝酸盐的含量,降低了可滴定酸的含量。施肥处理显著增加了0-60cm土层硝态氮含量,满足了甜椒在不同时期对氮素的需求。控释氮肥处理0-60cm土层铵态氮含量差异不大,常规施肥铵态氮含量明显下降。综合考虑在农民习惯性施肥基础上施用70%控释氮肥可以保证较高的产量和较好的果实品质。     

不同施氮量对高粱产量及植株养分积累的影响

利用控制性的大田试验栽培技术,连续2a采用氮的添加试验,研究了不同施氮量(CK、低氮LN、中氮MN、高氮HN)对高粱(Sorghum bicolor)产量及植株养分积累的影响。结果表明:施氮处理下高粱植株株高、根长、叶面积指数、茎粗、地上和地下生物量均高于对照,随着氮浓度的增加,高粱植株生长各指标以中水平施氮(MN)处理下达到最大,说明施氮能够促进高粱的生长,但氮肥在高用量时可能会产生轻微抑制作用;施氮对高粱植株叶绿素、可溶性蛋白和可溶性糖含量均有明显的促进作用,不同施氮处理下高粱叶绿素a和b、可溶性糖和可溶性蛋白含量呈先增加后减小的趋势,说明施氮能够促进高粱叶片叶绿素合成;高粱植株不同部位的碳、氮、磷和钾积累量表现出较大的差异,穗部的碳、氮、磷和钾积累量最高,其次是叶片,根部碳、氮、磷和钾积累量最低,其中不同部位的碳、氮、磷和钾积累量均表现为MNHNLNCK,由此表明了施氮能够增加高粱碳、氮、磷和钾的积累量;施氮对高粱植株养分的影响表现为一定程度的增加效应,随施氮量的增加高粱植株养分呈先增加后降低的趋势,表明了高粱植株在一定程度上对养分的累积作用,其增幅随施氮量的增加而增加。Pearson相关性分析表明,施氮量与株高、茎粗、单株叶面积、单株干重、籽粒产量、穗数和千粒重呈现出显著性相关关系,由此表明,施氮量与高粱主要性状以及养分吸收息息相关,在高粱高产高效栽培中起着重要的作用。     

Yield Comparison of Nonstructural Carbohydrates in Sweet Sorghum and Legume-Based Cropping Systems

Field experiments were conducted during dry (2009/10) and wet (2010) seasons to evaluate sweet sorghum–legume-based cropping systems for soluble sugars and starch production. Treatments were composed of two types of legumes (mung bean, soybean), two planting patterns (alternate single rows, alternate double rows), and two times of seeding (simultaneous, staggered) together with three monocrop treatments of sweet sorghum, mung bean, and soybean in randomized complete block design. Key observations indicated that the average yields of soluble sugars and starch were significantly reduced in intercropping systems in both seasons, due to partial or interactive influence of treatments considered. Yields of soluble sugars and starch were increased by 6 and 11% in the dry season and by 5 and 19% in the wet season in sweet sorghum–soybean and sweet sorghum–mung bean associations, respectively, when established with staggered seeding compared to those in simultaneously seeded combination or in monocropping of sweet sorghum.     

Sugar beet yield response to different levels of saline irrigation water and leaching in an arid region

The main objective of this work was to evaluate the effects of saline irrigation water and leaching on the sugar beet yield components. In a field experiment in Rudasht region (Isfahan, Iran), three irrigation water salinity levels (1.6, 8.1, and 12.3 dS m^?1) and with/without leaching were applied. The experimental units comprised of a completely randomized block design, with split plot in four replications. The results indicated that the white sugar yield and alkalinity decreased by increasing the water salinity. Salts leaching significantly increased the root yield, white sugar yield, and white sugar concentration. With higher levels of water salinity molasses sugar, leaf weight, and the concentrations of Na, K, and α- amino-N in sugar beet significantly increased. Consequently, it appears that the use of drainage water in combination with fresh water could be recommended as a strategic management way to grow sugar beet in the investigated arid region.     

Effects of Tea Plant Compost and Mineral Nitrogen Levels on Yield and Quality of Sugar Beet Crop

A field experiment was carried out during two successive seasons of 2009–2010 and 2010–2011 at Sakha Agriculture Reseach Station, Egypt, to study the effects of different applications of compost tea (C) under three mineral nitrogen (N) levels and their interaction effects on sugar yield and juice quality characteristics of sugar beet (Beta vulgaris L.), and soil available nutrients. Results indicated that the sugar yield and juice quality characteristics of sugar beet were significantly increased with compost tea treatments, especially in the plots treated with compost tea foliar application in three batches. A quality percentage of sugar beet was increased about 8.0% in the plots treated with compost tea or interaction between N mineral N and compost tea treatments above the control treatment. The interaction between mineral N and compost tea treatments had a significant effect on sugar yield, sugar percentage, purity, and quality of sugar beet and soil fertility.     

陇东山旱地夏播复种饲用甜高粱品种筛选

陇东山旱地区为陇东肉羊肉牛产业的重要生产区,其长期饲草供应不足,困扰产业发展。为探明山旱地夏播复种饲用甜高粱的干草生产力状况,增加饲草生产能力,引进了4个饲用甜高粱品种在陇东山旱地开展试验。结果表明,甜高粱2180收割高度最高,为169.53 cm;其次是陇甜粱1号,为160.87 cm。茎粗以海牛最高,为11.20 mm;陇甜粱1号、甜高粱2180较高,分别为10.20、10.00 mm。鲜草产量、干物质产量均以甜高粱2180最高,分别为35 073.68、14 985.53 kg/hm2;其次是陇甜粱1号,分别为30 797.60、12 385.86 kg/hm2。陇甜粱1号的可溶性糖含量(268.3 g/kg)、干物质采食量(2.24%)、相对饲用价值(110.20)和可消化营养物(57.84)均为最高,其次是甜高粱2180。综合分析,陇甜粱1号和甜高粱2180产草量高,营养价值较高,可在陇东地区山旱地种植。     

Soil Fertility,Mineral Nitrogen,and Microbial Biomass in Upland Soils of the Central Amazon under Different Plant Covers

Amazon is the largest state in Brazil and majority of the state is covered by the largest tropical rainforest of the world. Most soils of the Amazon region soils are acidic and infertile. When the Amazon forest land is cleared for agricultural use by burning the vegetation, the efficient nutrient recycling mechanisms are disrupted. However, nutrient contents in the deforested burn land increased temporarily. The objective of this study was to evaluate the soil fertility, mineral nitrogen (N), and microbial activity of carbon (C), N, and phosphorus (P) resulting from the replacement of the primary forest with pasture (Brachiaria brizantha) and commercial plantations of rubber (Hevea spp.), cupuaçu (Theobroma grandiflorum), and citrus trees (Citrus sinensis) cultivated in Xanthic Ferralsol and secondary forest under Acrisols Dystric Nitosols. The results showed that ammonium-N predominates in the 0- to 10-cm soil depth in both primary forest and areas with secondary forest, citrus plantation, and pasture. There was no increase in soil fertility with management of the cultivated areas under the secondary forest, but in the pasture there was a significant increase in the stock of organic C and total N and high C/N ratios, the inverse of what occurred with the C of the microbial biomass. The primary forest had the greatest values of C and P of the microbial biomass and the lowest metabolic quotient. Of the successions studied, the rubber trees were the plant cover with the smallest changes in terms of quality of the organic matter in the soil.     

Interactive Influences of Salinity Stress and Leaf Thinning on the Growth,Yield, Water use Efficiency,and Fruit Quality of Cherry Tomatoes

This research has experimentally investigated the interactive influences of salinity stress and leaf thinning on the growth, yield, water use efficiency, and fruit quality of cherry tomatoes cultivated under soilless conditions. The experiment was conducted in a plastic house (width of 5 m and length of 11 m) located in Gifu University. The seedlings were transplanted in a randomized complete block design with six plants per treatment, and a total of 36 plants in 18 pots (two plants per pot). The experiment received salinity treatment (no-salinity and salinity with electrical conductivity (EC) of 0.8 dS m^?1 and 3.0 dS m^?1, respectively) and leaf thinning treatment (no leaf thinning, basal leaf thinning and intersegment leaf thinning except the closest two). The experimental results showed that salinity stress negatively affected the growth, yield, marketable yield and water use efficiency of cherry tomatoes, but positively affected the fruit quality. Basal leaf removal significantly decreased the biomass, chlorophyll, and yield but significantly improved the fruit quality; that basal leaf removal coupled with salinity stress showed no influence on plant growth, but reduced the yield and greatly improved the fruit quality. Besides, tender leaves around truss removal significantly decreased the biomass, chlorophyll, yield, and water consumption, but improved the fruit quality; that tender leaves around truss removal coupled with salinity stress greatly decreased the biomass, chlorophyll, yield, and water consumption, but significantly improved the fruit quality.     

Sugar beet and Barley Yields in Relation to Bacillus polymyxa and Bacillus megaterium var. phosphaticum Inoculation

Microbiological fertilizers are an important part of environment friendly sustainable agricultural practices. A study was conducted in order to investigate seed inoculation of sugar beet (cv. Sonja) and barley (cv. Tokak), with nitrogen fixing (Bacillus polymyxa) and phosphate dissolving (Bacillus megaterium var. phosphaticum) bacteria in comparison to control and mineral fertilizer application in the green house and in the field at two sites in 1996 and 1997 in Erzurum (29^o 55' N and 41^o 16' E with an altitude of 1950 m), Turkey. In the green house trial bacterial inoculation of seeds increased sugar beet root and barley seed yields compared with control. B. polymyxa was more effective, but dual inoculations gave increases of 19.0 and 25.9% respectively. In the field as an average of sites and years sugar beet root yields were increased by 12.0%, 7.5% and 16.5% while barley seed yields were increased by 15.0%, 8.4% and 18.2% respectively with B. polymyxa, B. megaterium var. phosphaticum and dual applications over control treatment. Other yield and yield components were also enhanced especially by dual applications. However, increases in yield and yield components were lower than or comparable to mineral fertilizer application. The beneficial effect of bacterial inoculation was higher in well irrigated pot trials and at the site of rich clayey soils. In conclusion, microbial inoculation of seeds with Bacillus polymyxa and B. megaterium var. phosphaticum, alone or in dual combinations, may substitute costly NP fertilizers in sugar beet and barley production even in cold highland areas such as in Erzurum.     

Effect of Salinity and Nitrogen Application on Growth,Chemical Composition and Some Biochemical Indices of Pistachio Seedlings (Pistacia Vera L.)

To study the effect of nitrogen and salinity on growth and chemical composition of pistachio seedlings (cv. ‘Badami’), a greenhouse experiment was conducted. Treatments consisted of four salinity levels [0, 800, 1600, and 2400 mg sodium chloride (NaCl) kg^?1 soil], and four nitrogen (N) levels (0, 60, 120, and 180 mg kg^?1 soil as urea). Treatments were arranged in a factorial manner in a completely randomized design with three replications. The highest level of nitrogen and salinity decreased leaf and root dry weights. Nitrogen application significantly increased the concentration of shoot N and salinity suppressed shoot N concentration. Salinity and nitrogen fertilization increased shoot and root sodium (Na), calcium (Ca), and magnesium (Mg) concentrations. Nitrogen application increased proline concentration and reducing sugar content. Although salinity levels increased proline concentration a specific trend on reducing sugars content was not observed.     

Influence of Salinity on Chlorophyll,Leaf Water Potential,Total Soluble Sugars,and Mineral Nutrients in Two Young Olive Cultivars

The effect of salinity (NaCl) on chlorophyll, leaf water potential, total soluble sugars, and mineral nutrients in two young Iranian commercial olive cultivars (‘Zard’ and ‘Roghani’) was studied. One-year-old trees of these cultivars were planted in 10-L plastic pots containing equal ratio of sand-perlite mixture (1:1). Sodium chloride at concentrations of 0, 40, 80, 120, or 160 mM plus Hoagland's solution were applied to these pots for 150 days. The results showed that chlorophylls (a), (b), and (a+b) reduced with increasing of salinity up to 40 mM. There was no difference between cultivars for chlorophylls (b) and (a+b) while ‘Roghani’ showed more decreased in content of chlorophyll (a) than did ‘Zard’. Total soluble sugars in leaves increased with an increase in salinity up to 80 mM but decreased with additional increase in salinity. Salinity stress reduced water potential equally in both cultivars. The concentrations of sodium (Na) and chloride (Cl) and Na/potassium (K) ratio were increased and K decreased with increasing of salinity up to 80 mM in leaves and roots. Concentrations of K, magnesium (Mg), calcium (Ca), phosphorus (P), and nitrogen (N) reduced significantly in leaves, shoots and roots with increasing salinity.     

Distribution of K, Na and Cl in Root and Leaf Cells of Soybean and Cucumber Plants Grown under Salinity Conditions

The element contents in the compartments of root and leaf cells of soybean and cucumber plants grown for 8 d in a nutrient solution containing 50 mM NaCl, 25 mM CaCl₂ or 50 mM NaCl+4.75 mM CaSO₄ were examined by X-ray microanalysis of freeze-substituted dry sections. Sodium accumulated in the vacuoles rather than in the cytoplasm and apoplastic space in the root cells of the soybean plants, leading to the difficulty in the transport of Na to leaves in soybean. Salt injury of soybean is considered to be caused by the accumulation of Cl at high concentrations in all the compartments of root and leaf cells. In contrast, the accumulation of Na in the cytoplasm of the root and leaf cells might disturb the metabolism and lead to the occurrence of salt toxicity in cucumber plants, which are tolerant to Cl due to the stimulation of Cl accumulation in vacuoles when the Ca concentration was high in nutrient media.     

有机无机不同用量配施对煤矿复垦土壤氮素利用及矿质氮含量的影响

采煤塌陷新复垦土壤有效氮含量低而有机无机培肥过程中氮有效性变化尚不明确,依托定位培肥试验基地(山西省孝义市水峪煤矿采煤塌陷复垦土壤),设置8个不同处理包括3个有机无机不同用量配施处理(鸡粪与化肥1∶1氮量在100,150,200 kg/hm~2配施,表示为MF100、MF150、MF200),与单施不同用量化肥氮(0,100,150,200 kg/hm~2,表示为IF0、IF100、IF150、IF200)相比较,以不施肥为对照(CK)。通过测定玉米产量、植株吸氮量、氮肥利用率及作物收获后土壤剖面矿质氮含量,确定适合该矿区复垦土壤施肥处理和最佳氮肥用量,从而为高产高效培肥矿区复垦土壤提供科学理论依据。结果表明:(1)施氮量为150 kg/hm~2的等养分条件下,MF150比IF150玉米籽粒产量提高了12.45%,差异显著(P0.05);同时MF150处理与IF200、MF200处理间差异均不显著(P0.05)。(2)玉米地上部吸氮量随施氮量的增加而增加,且等氮量条件下,鸡粪和化肥配施能显著提高玉米吸氮量(P0.05),增幅为39.45%～41.46%。(3)等氮量条件下,鸡粪和化肥配施较单施化肥处理能显著提高氮肥回收率;不同施肥模式的氮肥偏生产力均随施氮量的增加呈现下降趋势;IF100处理氮肥农学利用率最高为24.08 kg/kg,并且该处理与MF150无显著差异,而等氮量下MF150较IF150处理的氮肥农学效率显著增加(提高了49.56%)。(4)作物收获后0—40 cm土壤剖面矿质氮含量随土层深度而增加,但是等氮量各施肥处理间无显著差异,40—60 cm剖面中单施化肥氮各处理矿质氮残留量较配施各处理提高了约18%。总之,MF150施肥处理不仅提高作物产量、吸氮量和氮肥利用率,而且土壤剖面矿质氮残留较少,可作为培肥该矿区复垦土壤或与本试验土壤类型相似的低产农田的推荐施肥量。     

Distribution of K,Na and Cl in Root and Leaf Cells of Soybean and Cucumber Plants Grown under Salinity Conditions

The element contents in the compartments of root and leaf cells of soybean and cucumber plants grown for 8 d in a nutrient solution containing 50 mM NaCl, 25 mM CaCl₂ or 50 mM NaCl+4.75 mM CaSO₄ were examined by X-ray microanalysis of freeze-substituted dry sections. Sodium accumulated in the vacuoles rather than in the cytoplasm and apoplastic space in the root cells of the soybean plants, leading to the difficulty in the transport of Na to leaves in soybean. Salt injury of soybean is considered to be caused by the accumulation of Cl at high concentrations in all the compartments of root and leaf cells. In contrast, the accumulation of Na in the cytoplasm of the root and leaf cells might disturb the metabolism and lead to the occurrence of salt toxicity in cucumber plants, which are tolerant to Cl due to the stimulation of Cl accumulation in vacuoles when the Ca concentration was high in nutrient media.