EFFECTS OF PLANT GROWTH PROMOTING BACTERIA ON YIELD,GROWTH, LEAF WATER CONTENT,MEMBRANE PERMEABILITY,AND IONIC COMPOSITION OF STRAWBERRY UNDER SALINE CONDITIONS

Plant growth promoting effects of Bacillus subtilis EY2, Bacillus atrophaeus EY6, Bacillus spharicus GC subgroup B EY30, Staphylococcus kloosii EY37 and Kocuria erythromyxa EY43 were tested on strawberry cv. ‘Fern’ in terms of fruit yield, growth, chlorophyll reading value, leaf relative water content (LRWC), membrane permeability and ionic composition of leaves and roots under saline conditions. Compared with 0 mM sodium chloride (NaCl) treatment, the average decrease of yield and LRWC were 51.6% and 21.0%, respectively, when 35 mM NaCl was applied. However, EY30, EY37, and EY43 treatments under saline condition (35 mM NaCl) significantly increased fruit yield (54.4%, 51.7% and 94.9%) compared with 35 mM NaCl treatment without plant growth promoting bacteria (PGPB). The LRWC increased from 72.0% in 35 mM NaCl treatment to 88.4%, 86.6%, 84.2%, 83.5%, and 86.2% by EY2, EY6, EY30, EY37, and EY43 applications, respectively. The lowest membrane permeability among the bacterial strains was obtained from EY37 treatment (37) while it was 33 and 58 in 0 mM NaCl and 35 mM NaCl treatments, respectively. The concentration of all plant tissue nutrients investigated [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg)] with the exception of root phosphorus (P) and Mg concentration significantly decreased with 35 mM salt treatment. Nitrogen content of leaves varied between 3.04 and 3.14% in bacterial treatments under saline conditions while it was 2.71% in 35 mM NaCl treatment. In contrast sodium (Na) and chloride (Cl) of leaves and Cl content of roots were significantly decreased by root inoculation with all bacterial treatments in comparison to 35 mM NaCl treatment with no inoculation. Treatment with Bacillus EY30, Staphylococcus EY37 and Kocuria EY43 to strawberry plants can ameliorative the deleterious effect of salt stress on fruit yield, growth and nutrition. These results demonstrate that PGPB treatment could be offer an economic and simple means to increased plant resistance for salinity stress.     

PLANT GROWTH PROMOTING RHIZOBACTERIA INCREASE GROWTH,YIELD AND NITROGEN FIXATION IN PHASEOLUS VULGARIS

Nitrogen (N) fixation by legume-Rhizobium symbiosis is important to agricultural productivity and is therefore of great economic interest. Growing evidence indicates that soil beneficial bacteria can positively affect symbiotic performance of rhizobia. The effect of co-inoculation with plant growth-promoting rhizobacteria (PGPR) and Rhizobium, on nodulation, nitrogen fixation, and yield of common bean (Phaseolus vulgaris L.) cultivars was investigated in two consecutive years under field conditions. The PGPR strains Pseudomonas fluorescens P-93 and Azospirillum lipoferum S-21 as well as two highly effective Rhizobium strains were used in this study. Common bean seeds of three cultivars were inoculated with Rhizobium singly or in a combination with PGPR to evaluate their effect on nodulation and nitrogen fixation. A significant variation of plant growth in response to inoculation with Rhizobium strains was observed. Treatment with PGPR significantly increased nodule number and dry weight, shoot dry weight, amount of nitrogen fixed as well as seed yield and protein content. Co-inoculation with Rhizobium and PGPR demonstrated a significant increase in the proportion of nitrogen derived from atmosphere. These results indicate that PGPR strains have potential to enhance the symbiotic potential of rhizobia.     

RESPONSE OF WHEAT TO INOCULATION WITH MYCORRHIZAE ALONE AND COMBINED WITH SELECTED RHIZOBACTERIA INCLUDING FLAVOBACTERIUM SP. AS A POTENTIAL BIOINOCULANT

A pot experiment was conducted to evaluate different arbuscular mycorrhiza sps. (AM) for their effect on plant growth, yield and nutrient uptake by wheat. All the AM fungal sps. significantly enhanced all the plant parameters and nutrient uptake by the plant. A positive correlation was observed between percent root colonization by AM fungi and most of the plant parameters studied. Glomus macrocarpum giving best results was selected for studying interactive effect with Azotobacter, Azospirillum (well-known PGPRs), and Flavobacterium and Proteus vulgaris (less studied PGPRs). All the PGPRs significantly increased most of the plant parameters studied and their combination with AMF had a synergistic effect. Amongst PGPRs, Flavobacterium gave best response both singly and in combination with AMF and thus, is a potential new bioinoculant for wheat. Application of 120 kg nitrogen (N) ha^?1was the best treatment. Inoculation with most of the PGPRs gave better response than 60 kg N ha^?1.     

GROWTH,YIELD, AND ION RELATIONS OF STRAWBERRY IN RESPONSE TO IRRIGATION WITH CHLORIDE-DOMINATED WATERS

Strawberry is listed as the most salt sensitive fruit crop in comprehensive salt tolerance data bases. Recently, concerns have arisen regarding declining quality of irrigation waters available to coastal strawberry growers in southern and central California. Over time, the waters have become more saline, with increasing sodium (Na⁺) and chloride (Cl^?). Due to the apparent extreme Cl^? sensitivity of strawberry, the rising Cl^? levels in the irrigation waters are of particular importance. In order to establish the specific ion causing yield reduction in strawberry, cultivars ‘Ventana’ and ‘Camarosa’ were grown in twenty-four outdoor sand tanks at the ARS-USDA U. S. Salinity Laboratory in Riverside, CA and irrigated with waters containing a complete nutrient solution plus Cl^? salts of calcium (Ca²⁺), magnesium (Mg²⁺), Na⁺, and potassium (K⁺). Six salinity treatments were imposed with electric conductivities (EC) = 0.835, 1.05, 1.28, 1.48, 1.71, and 2.24 dS m^?1, and were replicated four times. Fresh and dry weights of ‘Camarosa’ shoots and roots were significantly higher than those of ‘Ventana’ at all salinity levels. Marketable yield of ‘Camarosa’ fruit decreased from 770 to 360 g/plant as salinity increased and was lower at all salinity levels than the yield from the less vigorous ‘Ventana’ plants. ‘Ventana’ berry yield decreased from 925 to 705 g/plant as salinity increased from 0.835 to 2.24 dS m^?1. Relative yield of ‘Camarosa’ decreased 43% for each unit increase in salinity once irrigation water salinity exceeded 0.80 dS m^?1. Relative ‘Ventana’ yield was unaffected by irrigation water salinity up to 1.71 dS m^?1, and thereafter, for each additional unit increase in salinity, yield was reduced 61%. Both cultivars appeared to possess an exclusion mechanism whereby Na⁺ was sequestered in the roots, and Na⁺ transport to blade, petiole and fruit tissues was limited. Chloride content of the plant organs increased as salinity increased to 2.24 dS m^?1 and substrate Cl increased from 0.1 to13 mmol_cL^?1. Chloride was highest in the roots, followed by the leaves, petioles and fruit. Based on plant ion relations and relative fruit yield, we determined that, over the range of salinity levels studied, specific ion toxicity exists with respect to Cl^?, rather than to Na⁺ ions, and, further, that the salt tolerance threshold is lower for ‘Camarosa’ than for ‘Ventana’.     

RESPONSE OF SALT STRESSED STRAWBERRY PLANTS TO FOLIAR SALICYLIC ACID PRE-TREATMENTS

Salinity has deleterious effects on plant growth and development through membrane stability, photosynthetic activity, protein content, and ionic composition; however, salicylic acid (SA) could restore these properties in plants. The objective of this study was to determine the ameliorative effects of SA as foliar pre-treatments on membrane permeability, proline and protein contents, chlorophyll a, b and total chlorophyll and ionic composition of strawberry cv. ‘Camarosa’ under saline conditions. Membrane permeability and proline content significantly increased and protein and chlorophyll contents significantly decreased by 6 mS cm^?1 application without SA treatment compared with the control (2 mS cm^?1) treatment. Membrane permeability decreased from 6.9 in 0 mM SA treatment to 5.2 by application of 1.0 mM SA under saline conditions and same to the control (5.2). Compared with 0 mM SA treatment, the average increases of proline and protein contents were 66.7% in 0.25 mM SA treatment and 62.2% in 0.1 mM SA treatment in 6 mS cm^?1 level, respectively. Chlorophyll b and total chlorophyll significantly increased by 0.25 mM SA treatments under saline conditions. The lowest and the highest chlorophyll b and total chlorophyll were obtained from 0 mM SA treatment (19.6 and 44.5 mg L^?1) and 0.25 mM SA treatment (28.6 and 52.9 mg L^?1) in 6 mS cm^?1 salinity level. Ionic compositions of leaves were significantly affected by salinity and SA treatments. Nitrogen in 1.0 mM SA treatment and P contents of leaves in 0.1 mM SA treatment significantly increased but Na and Cl contents of leaves significantly decreased by SA treatments in 6 mS cm^?1 salinity level. The results of this study were clearly indicated that the SA application on strawberry plants could ameliorate the deleterious effect of salt stress on membrane permeability, proline, protein, and chlorophyll contents. Therefore, SA treatment could offer an economic and simple application to salinity stress.     

影响根癌农杆菌介导的丰香草莓遗传转化因素分析

将构建的携带NPTⅡ和AP-D基因的植物表达载体pBI121导入根癌农杆菌EH105中后,用其对草莓主栽品种丰香叶盘进行遗传转化,探讨了卡那霉素(Kan)的浓度、菌液浓度、侵染时间、预培养时间、共培养时间和筛选方式等因素对转化率的影响。结果表明:丰香草莓适宜的转化条件是Kan筛选浓度为20 mg/L,预培养时间为2~3 d,菌液浓度OD6000.3~0.5,侵染时间10~20 min;共培养2~3 d后将外植体接到含有5 mg/L Kan和500 mg/L Carb的诱导培养基上进行培养,以后每次继代逐步提高Kan选择压力至终浓度20 mg/L(每次增加5 mg/L);或共培养2~3 d后将外植体接到含有500 mg/L Carb的诱导培养基上,培养2周后继代到含20 mg/L Kan和400 mg/L Carb的培养基上进行选择培养。根据PCR检测结果,抗性愈伤组织转化率高达18.5%。抗性愈伤组织经进一步诱导,最后获得了17株抗性植株。本文探讨了影响丰香草莓转化的多个因素,以期建立高效的遗传转化体系,为草莓属植物种质的遗传转化奠定基础。     

RESPONSE OF MAIZE GROWN IN AN ALFISOL OF SRI LANKA TO INOCULANTS OF PLANT GROWTH PROMOTING RHIZOBACTERIA

Field experiments were conducted to assess the ability of rhizobacterial inoculants to enhance growth and yield of maize. Performances of two phosphorus (P)-solubilizing bacteria in combination with a fertilizer mixture containing rock phosphate and triple super phosphate (PFM), and five diazotrophs combining either with 150 kg or 100 kg nitrogen (N) ha^?1 supplied as urea were compared with non-inoculated-fertilized controls. Shoot P and N and soil available P and N contents were assessed and shoot biomass and ear weights were recorded at harvest. Pseudomonas cepacia resulted in significantly higher available P (51 mg P kg^?1 soil), P accumulation (3.6 g kg^?1 dry matter) and 13% increase in shoot biomass over control. Azospirillum sp. and dual inoculant comprising Enterobacter agglomerans + Agrobacterium radiobacter led to significantly higher available N (74–94 mg kg^?1 soil) and 19 to 26% increase in shoot biomass over the control. However, inoculants did not increase the yield significantly.     

INOCULATION EFFECTS OF PANTOEA AGGLOMERANS STRAINS ON GROWTH AND CHEMICAL COMPOSITION OF PLUM

In this study, five non-pathogenic Pantoea agglomerans strains were utilized. The objective of this study was to test for biochemical characteristics of these strains, and to evaluate their inoculation effects on fruit set rate, fruit pomological traits, fruit chemical compositions and some vegetative parameters of plum cultivar ‘Stanley’. The results showed that some of the tested strains had beneficial effects on the fruit set rate, fruit pomological traits, fruit chemical composition and/or some vegetative growth parameters of plum in comparison to the control. In conclusion, tested Pantoea agglomerans strains (especially RK-85) are the suitable inoculants for plum cultivation in cold areas such as Erzurum, and these strains may be considered as biofertilizer and protector sensitive plants against frost damage by applying in suitable timing and dose.     

EFFECT OF PLANT GROWTH-PROMOTING RHIZOBACTERIA STRAIN ON FREEZING INJURY AND ANTIOXIDANT ENZYME ACTIVITY OF WHEAT AND BARLEY

In 2009 a greenhouse experiment was conducted to determine the effects of boron (B) and plant growth-promoting rhizobacteria (PGPR) on wheat (Triticum aestivum spp. vulgare cv ‘Bezostiya’) and barley (Hordeum vulgare cv ‘Tokak’) on plant growth, freezing injury, and antioxidant enzyme capacity. Results showed that boron (0, 1, 3, 6, 9 kg B ha^?1) and PGPR application (Bacillus megaterium M3, Bacillus subtilis OSU142, Azospirillum brasilense Sp245 and Raoultella terrigena) at which 50% of leaves were injured (LT₅₀) values and ice nucleation activities in both plants were found statistically significant. Boron application with all PGPR strains decreased LT₅₀ values in wheat and barley plants under noncold stress (NCS) and cold stress conditions (CS). There were statistically significant differences between bacterial inoculation and B fertilizer in terms of root and shoot dry weight under NCS and CS conditions. Reactive oxidative oxygen species (ROS) and antioxidant enzyme activities (SOD, POD, CAT) were negatively affected CS conditions and decreased with reduced temperatures of media, but B and PGPR applications alleviated the low-temperature deleterious effects in both plants species tested. The lowest ROS and antioxidant enzyme (SOD, POD, CAT) of wheat and barley were observed with 6 kg B ha^?1 with R. terrigena.     

多功能保水剂对黄瓜生长及产量的影响

本文研究新型多功能保水剂对黄瓜生长,产量,品质及水分利用率的影响。试验结果表明,这种新型多功能保水剂可以提高土壤绝对含水量,有效的促进黄瓜营养生长,黄瓜产量、结果数、单果重和水分利用率,分别提高了13.12%、10.34%、2.52%、13.12%,但对品质影响不大。     

RESPONSE OF MAIZE GENOTYPES TO SEVERAL MYCORRHIZAL INOCULUMS IN TERMS OF PLANT GROWTH,NUTRIENT UPTAKE AND SPORE PRODUCTION

A greenhouse experiment was conducted at the University of Çukurova, Rhisosphere Lab, Adana, Turkey, on a growth medium to assess the impact of several selected mycorrhiza including indigenous AMF-maize hybrid combinations on spore production, plant growth and nutrient uptake. In the experiment, six maize (Zea mays L.) (Luce, Vero, Darva, Pegasso, P.3394, and P.32K61) genotypes were used. Control, Glomus mossea, G. caledonium, G. etunicatum, G. clarium, G. macrocarpum, G. fasciculatum, G. intraradices, Dr. Kinkon (Japanese species), indigenous mycorrhizae (Balcal? series) and cocktail mycorrhizae species spores were used. The growth of maize genotypes was found to depend on the mycorrhizal species. For shoot and root dry weight production G. intraradices is one of the most efficient mycorrhiza species on average on all maize genotypes. Genotypes P.3394 and P.32K61 produced the highest shoot and root dry weight as well. Pagasso and Darva genotypes compared to the other genotypes have high root colonization percentages. On average G. clarium inoculated plants also have high percentages of root colonization. It has been found that the P.32K61 genotype has a high phosphorus (P)% content and Pagasso genotypes have higher zinc (Zn) content uptake than other genotypes. G. clarium inoculated maize genotype plant tissues have high P% and Zn content. G. intraradices is also efficient for P and Zn uptake. Mycorrhizal dependent maize genotypes showed variability in P efficiency from inefficient to efficient genotypes.     

EFFECTS OF PHOSPHORUS SUPPLY ON GROWTH,YIELD, AND YIELD COMPONENTS OF SAFFLOWER AND SUNFLOWER

This study comparatively evaluates the phosphorus (P) requirement of safflower (Carthamus tinctorius L.) and sunflower (Helianthus annuus L.) in view of identifying low input oil crops. Both species responded strongly to increasing P supply with respect to plant growth and yield. Yield component analysis revealed that oil yield in safflower was affected by P deficiency mainly via the number of capitula per plant followed, in consecutive order, by the number of achenes per capitulum and the single achene mass (SAM). The major yield component influencing oil yield of sunflower was the number of achenes per plant, followed by the SAM. Contribution of the seed oil concentration to overall yield variation was insignificant for both species. Path coefficient analyses indicate that in sunflower total nitrogen (N) accumulated was found to be most important, while in safflower this holds true for both the total P and N accumulated. It was concluded that safflower cannot be considered a low-input oil crop in terms of its P requirement.     

MAIZE RESPONSE TO YIELD AND YIELD TRAITS WITH DIFFERENT NITROGEN AND DENSITY UNDER CLIMATE VARIABILITY

To study yield and yield traits of maize, two experiments were conducted in 2006 as spring and summer crops and repeated in 2007. Three plant populations (43, 53, and 67 thousands ha^-1) and three nitrogen (N) rates (90, 120 and 150 kg N ha^-1) were compared in a completely randomized block design with split plot arrangement. The treatments plant population was assigned to the main and N to sub plots in three replications. Sowing of spring crop was done in March and harvested in July and likewise the summer crop in July and harvested in November. Each experimental unit comprised of 5 × 6 m area having eight rows spaced 0.75 m. Experimental results revealed that grain yield (GY) of summer was higher than spring season. Higher GY was associated with increases in the plant population and nitrogen rate. The treatment plant population of 53,000 and 67,000 ha^-1 did not differ. However, each increase in the N rate significantly increased GY. This increase in the GY by increasing N was due to increases in the ear length (EL), ear diameter (ED), grain number (GN) and thousand grain weight (TGW). Increasing plant population of maize did not show any remarkable changes in the yield traits. The study revealed that differences in GY due to seasonal climate cannot be rewarded with increase in either plant population or nitrogen rates. Moreover, spring and summer season maize crops can economically be planted with 150 and 120 kg N ha^?1 at 53,000 and 67,000 ha^?1 populations, respectively, to save environment and production cost.     

RELATIVE RESPONSE OF FORAGE AND SEED YIELD OF ALFALFA TO SULFUR,PHOSPHORUS, AND POTASSIUM FERTILIZATION

A field experiment was conducted from 2000 to 2007 on three-year old alfalfa stand near Star City in northeastern Saskatchewan to determine the influence of balanced application of sulfur (S), phosphorus (P), or potassium (K) fertilizers on forage dry matter yield (DMY) and seed yield, protein concentration (PC) in forage, concentration and uptake of total nitrogen (N), P, K, S, and boron (B) in forage and seed, and residual soil extractable P, exchangeable K and sulfate-S. Appropriate application of S, P, or K fertilizer nutrients was required to obtain optimum yield, PC, and nutrient concentration and uptake, especially when alfalfa was grown for hay production. Yield response to fertilization was much more frequent and much higher when alfalfa was managed as hay compared to when managed for seed production. The results suggest the importance of proper fertilization in increasing longevity of alfalfa stands. Under both hay and seed plots, there was only a small increase in residual sulfate-S from S fertilization, but significant accumulation of extractable P mainly in the 0–15 soil layer from P application. There was relatively higher concentration of exchangeable K in soil in the seed plots than in hay plots. In hay plots, concentrations of residual exchangeable K in soil were negatively related to DMY, especially in 2007. The findings suggest that when a soil is testing low (or deficient) in a nutrient and alfalfa growth is reduced, then alfalfa producers should consider applying fertilizers to supply adequate amounts of nutrients that are lacking in the soil, especially for optimum forage production. However, it is still difficult to predict accurately if a profitable alfalfa seed yield response to fertilization would occur, particularly when soils are testing marginal in some nutrient levels and yields are negatively affected by abnormal weather conditions (drought soil moisture conditions reducing plant growth, wet, cloudy and cool weather conditions decreasing pollination activity and late summer and/or early autumn frost damage to seed formation) that often occur in the growing season in this region.     

灌水和生长调节剂对有色小麦产量和品质的影响

以有色小麦皖麦38、绿麦1号和kz6061为材料,在大田条件下,研究灌水和生长调节剂对有色小麦产量和品质的影响。结果表明,灌水处理对有色小麦千粒重、容重、籽粒产量和蛋白质产量影响不显著,灌3水较灌2水处理显著提高有色小麦醇溶蛋白含量,而显著降低干、湿面筋含量。不同粒色小麦的籽粒产量和蛋白质产量差异显著,kz6061的籽粒产量和蛋白质产量均显著高于皖麦38和绿麦1号。蛋白质及其组分含量、沉降值、面筋含量和面筋指数在不同粒色小麦中差异显著,沉降值和面筋指数以皖麦38最高,干、湿面筋含量以kz6061最高。生长调节剂处理对皖麦38的清蛋白和球蛋白,绿麦1号的球蛋白,kz6061的清蛋白、球蛋白、醇溶蛋白和谷蛋白含量均有一定影响,对有色小麦面筋指数亦有显著影响。     

RESPONSE OF ALFALFA SEED YIELD AND YIELD COMPONENTS TO PHOSPHORUS FERTILIZING SYSTEMS AND SEEDING RATE AT SEMI-SALINE SOIL CONDITIONS

To study the effects of phosphorus (P) fertilizer (cow manure, phosphorus solublizing bacteria) and sowing density on seed production of alfalfa, an experiment was laid out in a three-replicated split-split plot design with four phosphorus fertilizer rates (0, 30, 60 and 90 kg ha^?1) in main plots, three phosphorus-solublizing bacteria (9, 41strains, and no bacteria) in sub-plots and three sowing densities (2, 6 and 10 kg ha^?1) in sub-sub plots. The highest seed yield resulted from 60 and 90 kg P ha^?1. Application of bacteria strain 41 was more efficient than bacteria strain 9 in seed yield and 1000-seed weight. Seed yield at 6 seed kg ha^?1 treatment was higher than 10 kg ha^?1, although there was no significant difference between them. Based on the results of this experiment the triple application of P60, B41 and SD6 could be recommended as the best treatment for seed production of alfalfa (Cultivar ‘Nikshahri’) under the semi-saline condition.     

DYNAMICS OF FABA BEAN GROWTH AND NUTRIENT UPTAKE AND THEIR CORRELATION WITH GRAIN YIELD

Growth parameters and nutrient uptake of faba bean with 12 different genotypes were studied at the end of four subsequent growth periods, viz. first vegetative (V1), second vegetative (V2), first reproductive (R1) and second reproductive (R2) periods for two years and correlated with final grain yield. All parameters including plant height, leaf number, leaf area index (LAI), above ground plant dry matter (DM) and root DM, nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) uptake and concentration of N, P, K, Ca, and Mg showed different patterns with advancement of the growth period. All the mentioned parameters were fitted in either quadratic or linear equations. Significant correlations were found among nutrients, growth parameters and grain yield during different growth stages. On the basis of these experiments it was clear that nutrient uptake was directly related to biomass. In V2 and R1 biomass production was greatest resulting in high nutrient uptake. Among the growth parameters, biomass and LAI showed the highest significant correlation with grain yield. The findings especially models derived from two year data across twelve genotypes can be used for better fertilizer management of faba bean.     

INFLUENCE OF ELEVATED PHOSPHORUS LEVELS IN NUTRIENT SOLUTION ON MICRONUTRIENT UPTAKE AND DEFICIENCY SYMPTOM DEVELOPMENT IN STRAWBERRY CULTURED WITH FERTIGATION SYSTEM

The relationship between the total amount of micronutrients absorbed by the above-ground plant tissue and the occurrence of visible micronutrient deficiency symptoms in two strawberry cultivars as influenced by elevated phosphorus (P) levels in fertigation solution was investigated. The plants were cultured with a fertilizer solution containing 0, 0.5, 1, 2, 4, or 6 mM P and tissue nutrient content were determined at 120 days after transplanting. Young leaves of the plants grown with nutrient solution P levels higher than 4 mM and 2 mM, respectively, in ‘Keumhyang’ and ‘Seonhong’, developed interveinal chlorosis. Tissue concentrations (mg·kg^?1 dry weight) of metallic micronutrients [iron (Fe), copper (Cu), manganese (Mn), and zinc (Zn)] in both cultivars did not decrease, but the total amount absorbed by the aboveground plant tissue decreased in the treatments in which nutrient deficiencies were observed. These results indicate that total amount of micronutrients is a better indicator of P-induced micronutrient deficiency.     

GROWTH AND YIELD RESPONSES OF PLANTAIN GENOTYPES AS INFLUENCED BY ORGANIC AND INORGANIC FERTILIZERS

A field experiment was conducted for two cropping cycles to evaluate the growth and yield responses of four plantain genotypes (29525, 30456-3, PITA 14 and Agbagba) to fertilizer source (inorganic, organic fertilizer and no fertilizer) in a 4 × 3 factorial in a complete randomized block design. Genotype 29525 flowered and matured earliest, produced heaviest bunches and highest number of hands and fruits per bunch. Agbagba produced the tallest plants, longest, widest and heaviest fruits. Bunch weight was heavier with the application of inorganic or organic fertilizers. There were genotype and fertilizer interactions for bunch and fruit weights and length in the plant crop with genotype 29525 having the heaviest bunches whereas the heaviest and longest fruits were produced by Agbagba when no fertilizer was applied. Bunch yield per hectare increased with organic fertilizer application.     

YIELD AND YIELD COMPONENTS OF UPLAND RICE AS INFLUENCED BY NITROGEN SOURCES

Ammonium sulfate and urea are main sources of nitrogen (N) for annual crop production in developing countries. Two greenhouse experiments were conducted using ammonium sulfate and urea as N sources for upland rice grown on a Brazilian Oxisol. The N rates used were 0, 50, 100, 150, 3000, and 400 kg N kg^?1 of soil. Yield and yield components were significantly increased in a quadratic fashion with increasing N rate. Ammonium sulfate X urea interaction was significant for grain yield, shoot dry matter yield, panicle number, plant height and root dry weight, indicating a different response magnitude of these plant parameters to two sources of N. Based on regression equation, maximum grain yield was achieved with the application of 380 mg N kg^?1 by ammonium sulfate and 271 mg N kg^?1 by urea. Grain yield and yield components were reduced at higher rates of urea (>300 mg kg N) but these plant parameters’ responses to ammonium sulfate at higher rates was constant. In the intermediate N rate range (125 to 275 mg kg^?1), urea was slightly better compared to ammonium sulfate for grain yield. Grain yield was significantly related with plant height, shoot dry weight, panicle number, grain harvest index and root dry weight. Hence, improving these plant characteristics by using appropriate soil and plant management practices can improve upland rice yield.