CO-INOCULATION OF SOYBEAN (GLYCINE MAX) WITH ACTINOMYCETES AND BRADYRHIZOBIUM JAPONICUM ENHANCES PLANT GROWTH,NITROGENASE ACTIVITY AND PLANT NUTRITION

The aim of this study was to determine the potential of the endophytic actinomycetes that produce plant growth promoters used as co-inoculants with Bradyrhizobium japonicum to promote the growth of soybean. These endophytes exhibited the potential to enhance plant growth, nitrogenase activity of root nodules and plant nutrient uptake. Co-inoculum of B. japonicum with Nocardia alba conferred the maximum yield of root and shoot dry weight. All single-inoculated actinomycetes strains had the ability to enhance plant growth. Noc. alba and Nonomuraea rubra increased total plant dry weight up to 2.14-fold and 2.11-fold, respectively, when compared to the uninoculated controls. Co-inoculations of B. japonicum with each of Noc. alba, Non. Rubra, and Actinomadura glauciflava increased acetylene reduction activity up to 1.7 to 2.7-fold. For plant mineral composition, all of co-inoculation treatments significantly increased the nutrient levels of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe) and zinc (Zn) within a soybean plant.     

EFFECT OF PLANTING DATE,NITROGEN RATE,AND HYBRID ON SUNFLOWER

Sunflower is a potential crop for the southeastern United States for production of cooking oil or biodiesel. In 2007, we evaluated the effect of planting date (PD, 20 April, 20 May, and 20 June), nitrogen (N) application rate (0, 67, 134, and 202 kg ha^?1), and hybrid (‘DKF3875’, ‘DKF2990’, ‘DKF3510’, and ‘DKF3901’) on sunflower productivity and oil profile in four Mississippi locations, Newton, Starkville, and two sites in Verona. There was a trend of increased oleic acid concentration with earlier planting dates, especially in hybrids with lower oleic acid concentration. Earlier planting dates of ‘DKF3901’ and ‘DKF2990’ (the hybrid with the lowest oleic acid) actually had 200 to 300 g kg^?1 higher concentration of oleic acid when grown in Mississippi vs. the original seed of the same hybrids used for planting and produced at a more northern latitude. This and a recent study in Mississippi suggest that modern hybrids could provide ample yields even when the N fertilization is relatively low.     

DETERMINATION OF OLIVE MILL WASTEWATER TOXIC EFFECTS ON THREE MINT SPECIES GROWN IN HYDROPONIC CULTURE

The effects of two olive mill wastewater (OMW) dilutions upon physiological function and metabolic components of three mint species grown in hydroponic culture were studied. Visible symptoms, chlorosis and stunted growth, were pronounced in peppermint and spearmint; toxicity symptoms in menthe douce were few. Peppermint and spearmint displayed loss of calcium (Ca), magnesium (Mg), and potassium (K); menthe douce revealed accumulation of Ca, sodium (Na), and iron (Fe), under OMW. The loss of Ca negatively affected the development and stability of cell wall and membrane; the Mg deficiency negatively affected the photosynthetic apparatus and carbon fixation. Fv′/ Fm′ was slightly affected under OMW, whereas, Φ_PSII, q _P and Rfd displayed significant reductions. No clear effect of OMW on phenols and carbohydrates among the species were found. Ascorbic acid content in peppermint dropped dramatically; the reduction was lower for spearmint and menthe douce. The OMW resistant species, menthe douce, developed a mechanism to control the physiological and the biochemical status.     

四数花九里香精油化学成分研究

本文报道了采用GC-MS方法对广西德保产的四数花九里香(Murraya tetramera Huang)精油进行了定性、定量分析,共鉴定出12个化学成分,占精油总量的97.62％。主要成分为薄荷酮和异薄荷酮,含量高达71.06％,是一种新发现的富含薄荷酮的香料植物资源。     

利用改善液培养牛卵母细胞和早期胚胎的研究

在基础液 M199配制的培养液中,加入牛卵泡内的颗料细胞,置39℃、5%的 CO_2培养箱中培养72 h 后回收过滤液(简称改善液)。用这种不同浓度和保存时间的改善液,在体外成熟培养牛卵母细胞和胚胎时分别代替培养液和培养液加颗粒细胞制作的单层细胞培养体系。结果表明:(1)在基础液 M199中分别加入0%、25%、50%、75%、100%改善液和对照纽,其分裂率(78.7%～83.0%)组间均无差异(P>0.05);受精卵在体外培养至囊胚率,其中0%改善液组为30.4%,与对照组46.5%有显著差异(P<0.01);囊胚孵化率0%和25%改善液组分别为57.1%和57.9%,与对照组76.6%有显著差异(P<0.01)。(2)改善液保存时间为0 d,-4℃ 5～7 d,-20℃180 d 和对照组,分裂率(80.5%～86.3%)组间均无差异(P>0.05);受精卵在体外培养至囊胚率和囊胚孵化率,其中-20℃保存180 d 组分别为31.1%和54.5%,与对照组46.1%和72.0%有差异(P<0.05)。     

无机盐离子对早期牛胚胎在体外发育的影响

本研究系统的探索了培养液中的主要无机盐离子对早期牛胚胎在体外发育的影响。结果表明：培养液中的Ｎａ＋／Ｋ＋比显著影响牛胚胎在体外的发育，提高Ｋ＋浓度有降低囊胚率的作用，最适的Ｎａ＋／Ｋ＋比为１１４／３．２；Ｃａ２＋和Ｍｇ２＋同样为胚胎发育所必需，其最适浓度分别为２ｍｍｏｌ／Ｌ和０．５ｍｍｏｌ／Ｌ；培养液中添加２．８８ｍｇ／Ｌ的Ｚｎ２＋，其囊胚发育率显著高于空白对照组；培养液中添加０．０２５ｍｇ／Ｌ或０．２５ｍｇ／Ｌ的Ｃｕ２＋完全抑制囊胚发育。这表明Ｚｎ２＋对早期牛胚胎在体外发育有显著的促进作用，Ｃｕ２＋对早期牛胚胎在体外发育有强烈的抑制作用。     

THE EFFECT OF NITROGEN SOURCES ON YIELD AND QUALITY OF SALAD ROCKET GROWN IN DIFFERENT MONTHS OF THE YEAR

The effects of months of the year and nitrogen (N) sources on salad rocket (Eruca sativa Mill.) yield, quality, and nitrate accumulation was investigated during the years 2002 and 2003. In both years, seeds were sown on the first day of April, May, June, July, August and September. Three different nitrogen sources were used: farmyard (cattle) manure (100 tonnes·ha^?1), calcium nitrate [Ca(NO₃)₂]-15.5% N (150 kg N·ha^?1) and ammonium sulfate [(NH₄)₂SO₄)]-21% N (150 kg N·ha^?1). Yield, leaf color, dry matter, vitamin C and total glucosinolate content and nitrate accumulation was assessed. Growing months affected all the assessed parameters significantly both years, with the exception of hue angle in 2003, whereas nitrogen source only influenced yield and nitrate accumulation in 2003. In both years the highest yield was obtained in April, but vitamin C and total glucosinolate contents were higher during summer months, and leaves were slightly darker colored. Chemical fertilizers increased the yield compared to farmyard manure; however, they also increased nitrate accumulation slightly, without any significant difference between them. Nitrate accumulation never exceeded 300 mg kg^?1 fresh weight (FW), which is well below the acceptable daily intake of 3.7 mg nitrate per kg^?1 bodyweight set by European Commission's Scientific Committee on Food.     

EFFECT OF APPLIED LIME AND BORON ON THE AVAILABILITY OF NUTRIENTS IN AN ACID SOIL

Productivity of resources on acid soils occupying one fourth of the total area in India is abysmally low. Lime is applied to such soils with the primary objective of increasing the productivity of crops by enhancing the availability of native and applied plant nutrients. Greenhouse pot experiments and laboratory experiments were conducted to evaluate the effects of lime and boron (B) on the availability of nutrients in soils and their uptake by plants. The application of lime enhanced the available nitrogen (N,), phosphorus (P), calcium (Ca), magnesium (Mg), sulfur (S), and zinc (Zn) content in soils, which was reflected in their uptake by sunflower (Helianthus annus). On the contrary, availability of copper (Cu), iron (Fe), and manganese (Mn) in soil was reduced due to liming. Sunflower responded very well in terms of dry matter yield to B application to the extent of 175% and 188% under 1 and 2 mg kg^?1 applied levels of B, respectively. Dry matter yield of sunflower was reduced to the tune of 29.2 and 42.7% under 2/3 and 1 lime requirement (LR), respectively, over control. Lime application at 1/3 LR with 2 mg kg^?1 of applied B emerged as an optimum combination in acid soils.     

水稻叶色突变对虫害发生影响的研究初报

为明确叶色标记水稻在生产中可能引起的虫害发生变化,本试验在使用和不使用农药防治的情况下,以常规品种嘉禾218为对照,对龙特甫B及其2个叶色突变系黄玉B、翠玉B田间虫害情况进行了调查.龙特甫B为正常绿叶籼稻品种,黄玉B、翠玉B全生育期分别表现黄色和翠绿色,在苗期、分蘖期和抽穗期,黄玉B较龙特甫B的叶绿素含量分别下降58.O%,48.4%和40.8%,翠玉B则分别下降39.5%,36.0%和29.5%.结果表明,秧田期2个叶色突变体上的稻蓟马虫量显著高于其亲本龙特甫B;本田期灰飞虱和褐飞虱的虫口数在不同材料间或差异不显著,或存在显著差异,但没有一定的规律性.但是,2个突变体受稻纵卷叶螟的危害显著轻于龙特甫B,表现为盛发期突变体受稻纵卷叶螟危害产生的虫苞数显著少于龙特甫B,而龙特甫B与嘉禾218之间没有显著差异;相反,2个突变体植株上白背飞虱的虫量显著大于龙特甫B,龙特甫B也显著大于嘉禾218.根据植株的农艺性状和叶绿素含量,以及虫害发生动态变化,笔者推测,造成叶色标记水稻稻纵卷叶螟危害变轻的原因可能与植株叶绿素含量下降,影响幼虫生长发育有关,但引起白背飞虱虫口增加的原因尚需进一步研究.本试验为首次对叶色标记水稻虫害发生情况进行研究,所得结果不但对完善叶色标记水稻生产体系具有指导意义,同时对研究害虫与水稻叶色之间的关系也具有理论价值.     

EFFECT OF SOIL BUNDS ON RUNOFF,SOIL AND NUTRIENT LOSSES,AND CROP YIELD IN THE CENTRAL HIGHLANDS OF ETHIOPIA

The effects of soil bunds on runoff, losses of soil and nutrients, and crop yield are rarely documented in the Central Highlands of Ethiopia. A field experiment was set up consisting of three treatments: (i) barley‐cultivated land protected with graded soil bunds (Sb); (ii) fallow land (F); and (iii) barley‐cultivated land without soil bund (Bc). For 3 years (2007–2009), the effect of soil bunds on runoff, losses of soil and nutrients, and crop productivity was studied. Daily runoff and soil and nutrient losses were measured for each treatment using standard procedures while barley yield was recorded from the cultivated plots. The results showed that Sb brought about significant reduction in runoff and soil losses. Plots with Sb reduced the average annual runoff by 28 per cent and the average annual soil loss by 47 per cent. Consequently, Sb reduced losses of soil nutrients and organic carbon. However, the absolute losses were still high. This implies the need for supplementing Sb with biological and agronomic land management measures to further control soil erosion. Despite these positive impacts on soil quality, Sb do not increase crop yield. Calculated on a per‐hectare basis, Sb even reduce crop yield by about 7 per cent as compared with control plots, which is entirely explained by the reduction of the cultivable area by 8·6 per cent due to the soil bunds. Suitable measures are needed to compensate the yield losses caused by the construction of soil bunds, which would convince farmers to construct these land management measures that have long‐term beneficial effects on erosion control. Copyright © 2012 John Wiley & Sons, Ltd.     

INFLUENCE OF SALINITY AND AMMONIUM: NITRATE RATIO ON GROWTH,PHOTOSYNTHESIS, FATTY ACID AND THE ACTIVITY OF ANTIOXIDATIVE ENZYMES IN CANOLA

The effects of sodium chloride (NaCl) salinity (0 and 200 mM) and ammonium (NH₄):nitrate (NO₃) ratios (100:0, 25:75, 50:50, and 75:25) on growth, photosynthesis, fatty acids and the activity of antioxidative enzymes were investigated in canola plants. Leaf area and fresh and dry weights of leaves were significantly reduced by the salinity. The reduction in vegetative characteristics varied in both salinized and unsalinized plants according to the NH₄:NO₃ ratios so that the lowest reduction was observed with the 50:50 (NH₄:NO₃) ratio. Increased NH₄ up to 50 percent (50:50) of total N, promotes the yield at both salinized and unsalinized plants. In both salinized and unsalinized plants, the increased NH₄ and NO₃ ratio in the nutrient solution reduced the photosynthetic (Pn) rate and stomatal conductance; however, the reduction in Pn rate was severely impaired at a higher ratio of NH₄ in the nutrient solution. In both salinized and unsalinized plants, the 75:25 ratio had the lowest potassium (K) and sodium (Na) content; however, the K/Na ratio was the highest in 50:50 ratio. An increase of NH₄ in the solution led to a significant increase in NH₄ content in both salinized and unsalinized plants. Salinity increased NH₄ content so that the salinized plant had nearly twice as high NH₄ content in the leaves. The activity of nitrate reductase was increased by increasing NH₄ from 0 to 50% and then reduced at a higher ratio of NH₄ in the solution. The activities of antioxidative enzymes increased in salinized plants regardless of the NH₄:NO₃ ratios. In salinized plants, the activities of superoxide dismutase and catalase enzymes were increased by 44.4 % and 97.5%, respectively. Within salinized and unsalinized treatments, the highest activities of all antioxidant were observed in 75:25 ratio, while they remained unchanged for all NH₄:NO₃ ratios. The increased NH₄ content in the solution increased the oil content and the maximum oil content in both salinized and unsalinized plant was obtained in both 50:50 and 75:25 ratios. The percentage of oleic acid was affected by both salinity and NH₄:NO₃ ratios. The ratios of NH₄:NO₃ had no effect on the protein content; however, salinity reduced the protein content by 20%.     

INTERACTIVE EFFECT OF SULFUR AND NITROGEN ON GROWTH AND YIELD ATTRIBUTES OF OILSEED CROPS (BRASSICA CAMPESTRIS L. AND ERUCA SATIVA MILL.) DIFFERING IN YIELD POTENTIAL

Field experiments were conducted to determine the interactive effect of sulfur (S) and nitrogen (N) on growth and yield attributes of oilseed crops [Brassica campestris L. (V₁) and Eruca sativa Mill. (V₂)] differing in yield potential. Two combinations of S and N (in kg ha^?1): 0S + 100N (?S+N;T₁) and 40S + 100N (+S+N;T₂) were used. Biomass accumulation, leaf area index (LAI), leaf area duration (LAD), and photosynthetic rate in the leaves were determined at various phenological stages. The results showed that the combined application of S and N (+S+N) significantly (P<0.05) improved the growth and yield attributes of both the genotypes compared with N applied alone (?S+N). Genetic variability was observed between the two genotypes in response to combined application of S and N (T₂). Genotype V₁ had higher biomass accumulation, photosynthetic rate, seed yield, oil yield, biological yield, and harvest index when compared with genotype V₂. Treatment T₂ resulted in 142, 95, 56, and 349% enhancement in biomass accumulation, leaf-area index (LAI), leaf-area duration (LAD) and photosynthetic rate, respectively in comparison with treatment T₁ in genotype V₁. Seed yield, oil yield, biological yield, and harvest index were improved by 141, 171, 85, and 30%, respectively, by treatment T₂ in comparison with T₁. In the case of genotype V₂, increase in biomass accumulation, LAI, LAD, and photosynthetic rate due to application of treatment T₂ were 156, 137, 125 and 467%, respectively, over the results of T₁. Seed yield, oil yield, biological yield and harvest index improved by 193, 251, 98, and 48%, respectively, with this treatment. On the basis of results obtained in this study, it can be concluded that sulfur must be included in the nutrient management package for optimum growth and yield attributes of oilseed crops. Furthermore, the yield potential of oilseed crops with low seed and oil yield can be improved using this treatment as achieved in our study in case of taramira (Eruca sativa Mill.), a genotype with low seed and oil yield.     

EFFECT OF BORON-DOPED GOETHITE ON SOIL ACIDITY,DIFFERENT FORMS OF MANGANESE IN RED SOIL AND THE GROWTH OF RAPE (BRASSICA NAPUS L.) SEEDLINGS

Rape (Brassica napus L.) seedling pot experiments were performed with a red soil treated with goethite which had boron (B) either adsorbed (ad-B-goethite) or occluded (oc-B-goethite). Soil acidity, different forms of manganese in the soils and different elements content of the rape seedlings were determined. It was found that the addition of boron-containing goethite to the soils resulted in increased rape growth, elevated soil pH and decreased exchangeable acidity. Compared with the control, boron-containing goethite elevated the content of exchangeable manganese (Mn) (EXC-Mn), organic matter bound Mn (OM-Mn), reducible oxide Mn (RO-Mn) and residual Mn (RES-Mn) which were difficult to use for plant. Low labile organic matter was significantly correlated with easily reducible oxide Mn (ERO-Mn) (P < 0.01) and RO-Mn (P < 0.05). Middle organic matter and soil pH was significantly (P < 0.05) correlated with RES-Mn. Stepwise regression was used to select the combination of variables that best estimates shoot and root dry weight of rape seedling. Among them, soil pH, EXC-Mn, OM-Mn, RO-Mn and RES-Mn significantly influenced the dry weight of rape seedlings. The addition of boron-containing goethite improved the uptake of iron (Fe), calcium (Ca), magnesium (Mg), and copper (Cu) element and decreased the uptake of Mn and zinc (Zn) element in rape seedling. The results suggested that boron-containing goethite could provide a better soil acidity environment for plant growth; it was also an important agent increasing a part of manganese difficult to use for plant and reducing the activity of soil manganese, which was beneficial to altering rape seedling growth.     

SILICON ACCUMULATION AND ITS INFLUENCE ON SOME OF THE LEAF CHARACTERISTICS,MEMBRANE STABILITY AND YIELD IN RICE HYBRIDS AND VARIETIES GROWN UNDER AEROBIC CONDITIONS

Efforts to minimize water use in rice cultivation and stress tolerance are important in the present climate change scenario. Silica solubilizers might help in understanding the tolerance of plants to water deficit conditions or aerobic conditions. Rice cultivation in combination with silica was applied in the form of fertilizers (sodium silicate) and solubilizers (Imidazole and glycine) was studied in experimental farm and also in farmer's field. The varieties used were ‘KrishnaHamsa' (KH), ‘Rasi', ‘Jaya', hybrids ‘PA-6201' and ‘PHB-71' under aerobic conditions both in wet (Kharif) and dry (rabi) seasons. Transmission electron microscopy in this study provided evidence that silicon was deposited in the epidermal cell wall and the intercellular space of the silicon-treated rice leaves. The epidermal cell wall accumulation was absent in the control plants. Genotypic variation and treatment influences were observed for relative water content and cell membrane stability. Among the different rice cultivars ‘Rasi' followed by ‘PHB-71' and PA- 6201, were able to maintain cell membrane stability and chlorophyll content. Leaf rolling, chlorophyll, relative water contents, and dark adapted chlorophyll fluorescence were superior under aerobic conditions with application of solubilizers. However, significant differences in stomatal conductance were seen between seasons and genotypes. The silicon treated plants were able to maintain similar yields under aerobic conditions also as that of irrigated controls.     

EFFECT OF THE ECTOMYCORRHIZAL FUNGUS PAXILLUS INVOLUTUS ON GROWTH AND CATION (POTASSIUM,CALCIUM, AND MAGNESIUM) NUTRITION OF PINUS SYLVESTRIS L. IN SEMI-HYDROPONIC CULTURE

A semi-hydroponic culture was used to compare growth and cation nutrition of mycorrhizal (Paxillus involutus) and non-mycorrhizal Scots pine seedlings. When roots and hyphae grew together, concentrations and contents of macronutrients in needles and roots were not significantly different between mycorrhizal and non-mycorrhizal plants. When grown in two separate compartments, root potassium (K) concentrations, concentrations and contents of calcium (Ca) in needles and roots, needle nitrogen (N) concentrations, total N content and contents of root K and Mg were significantly reduced in mycorrhizal plants. Whereas ¹⁵N abundance increased in roots of mycorrhizal plants. The results indicated that the extraradical mycelium of the fungus strain used was able to transport N to the plant but did not contribute to long-term cation uptake and growth of host plants. An insufficient supply of macro-elements [N, phosphorus (P)] may account for the reduced growth of mycorrhizal plants and the differences in cation uptake between mycorrhizal and non-mycorrhizal plants.     

EFFECT OF DIFFERENT PHOSPHORUS SOURCES ON THE GROWTH,YIELD, ENERGY CONTENT AND PHOSPHORUS UTILIZATION EFFICIENCY IN MAIZE AT RAWALAKOT AZAD JAMMU AND KASHMIR,PAKISTAN

Effect of poultry manure (PM) and four inorganic phosphorus (P) fertilizers sources, i.e., diammonium phosphate (DAP), single super phosphate (SSP), nitrophos (NP) and triple super phosphate (TSP) on crop production and P utilization efficiency (PUE) of maize was studied. Both inorganic P fertilizers and PM applied alone or combined in 50:50 proportions at equivalent rate of 90 kg P₂O₅ ha^?1. Results indicated that inorganic P sources with PM significantly increased plant height, leaf area and chlorophyll content. Average values showed that combined application of inorganic P with PM increased grain yield by 19 and 41% over inorganic P and PM alone, respectively. Similarly, increase in P-uptake due to the combined application of inorganic P + PM was 17% compared to sole inorganic P. Phosphorus utilization efficiency of inorganic P was increased with PM and the highest PUE was recorded in DAP + PM. Generally, combination of DAP + PM proved superior over the remaining P fertilizers.