Open Access Short Research Article

Times of Potassium Application in Topdressing on the Soybean Crop

E. V. Zambiazzi, A. T. Bruzi, I. O. Soares, G. Felisberto, A. M. Zuffo, G. L. D. Vilela, P. M. de Rezende

Journal of Experimental Agriculture International, Page 1-6
DOI: 10.9734/AJEA/2015/19435

Potassium is exported in large amounts through grain harvest and this, together with the low availability of potassium in Brazilian soils, leads to an evident need for restoration of this nutrient. When the application rates of potassium are greater than 50 kg.ha-1, the most effective manner of utilizing the potassium is through topdressed fertilization after sowing. As such, the aim of this study was to establish the best time for topdressed application of potassium after sowing, as well as to study the effect of this nutrient on grain yield, on agronomic traits, and on potassium content in the grain. The experiment was carried out in the municipality of Lavras in the 2012/13 crop season. A randomized block design in an 8 x 4 factorial arrangement was used, composed of eight cultivars and four different periods of topdressed potassium application (20, 30, 40, and 50 days after sowing) for a total of 32 treatments with three replications. Potassium chloride at the rate of 120 Kg.ha-1 of potassium was used as a source. The results show that there was no effect of the time of topdressed application of potassium on the soybean crop for grain yield, for agronomic traits, and for potassium content in the grain

Open Access Original Research Article

Variability of Wheat Grain Image and Content of Phenolic Compounds and Carotenoids under the Impact of Selected Novel Plant Protection Treatments

Alicja Wasilewska, Iwona Konopka, Małgorzata Tańska, Urszula Wachowska

Journal of Experimental Agriculture International, Page 1-9
DOI: 10.9734/AJEA/2015/18819

Aims: Variability of wheat kernel size and color as well as the content of selected phytochemicals in wheat grain under the impact of selected biological and fungicide crop protection agents was investigated.

Study Design: A randomized block method in quadruplicate. Plants sprayed with Sphingomonas sp. bacteria in a tillering phase and during the period of winter wheat heading stage.

Place and Duration of Study: Field experiments: Department of Ento and Phytopathology, Tomaszkowo, Poland during vegetation seasons of 2009-10 and 2010-11.

Analytical Part: Chair of Food Plant Chemistry and Processing, Olsztyn, Poland

Methodology: Wheat plants were protected using Sphingomonas bacteria or Aureobasidium pullulans yeast preparations, or using chemical fungicides and the impact of plant growth promoters was also measured. Image features of kernels were measured using digital image analysis, total contents of grain phenolic compounds, phlobaphenes, flavonoids, proanthocyanidins and carotenoids using spectrophotometric assays, and phenolic acids using high-performance liquid chromatography.

Results: Length was the most constant dimension of grain, independent of the type of crop protection, with the coefficient of variation (CV) 0.98%. In contrast, the width varied with CV = 3.13% and thicknesses with CV = 3.53%. The average kernel surface hue (26.44° +/- 0.75) and saturation (27.37% +/- 0.92) values were higher and the intensity of color (61.80% +/- 0.81) was lower than these of cross-section (23.85° +/- 2.12 and 19.06% +/- 1.27, 70.48% +/- 1.64, respectively). Total Folin-Ciocalteu reactive compounds occured in the largest quantities (1045 to 1507 μg g-1). The least variable was content of phenolic acids (CV = 1.13%) and among this group – content of ferulic acid (CV = 0.73%).

Conclusion: It was found that the type of crop protection only slightly affected the variability of kernel dimensions and color. Kernels from control (unprotected) wheat plots were smaller and lighter, had less saturated color and were characterized by lower hue values as well as higher total phenolic compounds, and proanthocyanidins content. There were only minor differences between the biological and fungicide crop protection agents used.

Open Access Original Research Article

Application of Different Reclamation Methods on Salt Affected Soils for Crop Production

P. I. Ezeaku, J. Ene, Joshua A. Shehu

Journal of Experimental Agriculture International, Page 1-11
DOI: 10.9734/AJEA/2015/17187

Effects of salic conditions on soil properties under a given land use type and the methods for reclamation has not received the desired research attention in Nigeria. Understanding of how soil properties and crop yield respond to the influence of salic conditions is needed for employment of location-specific management strategies for the economic agricultural production. This study was conducted on salt affected soils during 2011/2012 and 2012/2013 crop years to investigate the soil physico-chemical properties and their effects on two maize cultivar growth and yield. Three approaches were employed to reclaim the salt affected soils in order to increase their efficiency and reduce the time of reclamation. Soils were sampled at two depth intervals: surface (0-15 cm depth) and subsurface (15-30 cm) for physical and chemical analysis. The experimental design was randomized complete block design (RCBD). The treatments were arranged in RCBD and replicated thrice. The treatment applications were 100% gypsum (CaS04) Gypsum requirement (GR); 25 Mg ha-1gypsum + farm yard manure (FYM) and chiseling. Leaching with irrigation water was done over a period of 2-4 hours per week. During the two cropping seasons, rice and millet crops were grown. Data collected were analysed statistically following ANOVA technique and treatment differences were evaluated using LSD test. Pre-cultivation soil analysis revealed a mean soil bulk density value of 2.37 g cm-3 and a value of 17.46 for total porosity. Soil pH showed alkalinity (>Pp7 pH 7.5) with high values of exchangeable bases and base saturation. Post-cultivation results show that highest yields of rice and millet were obtained from application of 100% gypsum. Yields obtained from gypsum + FYM treatments were, however, statistically similar. Yields from control treatment were consistently low. First millet post-harvest (2011/2012 crop year) soil test showed a reduction in electrical conductivity (ECe) value in all treatment plots except in control. The values of soil pH and sodium adsorption ratio (SAR) reduced after second millet harvest in 2012/2013 cropping season. The study found that soil chemical properties in control treatment did not improve, while combined use of gypsum + FYM + Chiseling appeared most effective in improving the soil conditions for land use sustainability

Open Access Original Research Article

Growth Response of Maize (Zea mays L.) to Different Rates of Nitrogen, Phosphorus and Farm Yard Manure in Morogoro Urban District, Tanzania

U. K. Adamu, Jerome P. Mrema, J. J. Msaky

Journal of Experimental Agriculture International, Page 1-8
DOI: 10.9734/AJEA/2015/19164

Pot experiments were carried out in the Teaching and Research Farm and in the green house of Soil Science Department, Faculty of Agriculture, Sokoine University of Agriculture, Morogoro Tanzania in 2014 and 2015 wet seasons to determine the effects of different levels of organic and inorganic fertilizers on maize. The experiments were conducted in completely randomized (CRD) with three replications. The treatments used consist of three levels of nitrogen (0, 75 and 150 kg Nha-1), three levels of phosphorus (0, 40 and 80 kg Pha-1) and three levels of Farm Yard Manure (0, 5 and 10 t FYM ha-1). Parameters determined includes plant height, number of leaves and stem girth. Results obtained showed that maximum plant height (66.75 and 131.7 cm), number of leaves (10.50) and stem girth (4.90 and 5.85 cm) were achieved with application of 150 kg Nha-1 + 80 kg Pha-1 + 10 t FYMha-1. The effects of treatments on parameters determined were significant (P≤0.05) in both years. However, application of fertilizers had no significant effect on number of leaves at first and second weeks after sowing. Results obtained in 2015 were better than 2014, which could be due to seasonal variation in the weather conditions and soils nutrient contents. The study suggests that, the study soils should be amended with rates of combined organic and inorganic fertilizers for superior maize growth performance

Open Access Original Research Article

Gene Pyramiding Improved Resistance to Angular Leaf Spot in Common Bean

G. Ddamulira, C. Mukankusi, M. Ochwo-Ssemakula, R. Edema, P. Sseruwagi, P. Gepts

Journal of Experimental Agriculture International, Page 1-12
DOI: 10.9734/AJEA/2015/17833

Aims: The study was conducted to determine the effectiveness of pyramided genes in improving angular leaf spot (ALS) resistance in susceptible common bean cultivars.

Study Design: The experiment was set in randomized block design with three replications. 

Place and Duration of Study: The experiment was conducted at International Centre for Tropical Agriculture (CIAT) at Kawanda, Uganda in 2010-2014.

Methodology: Crosses among three Pseudocercospora griseola resistant lines of common bean (Phaseolus vulgaris) were developed. The crosses involved five inbred lines, AND277, Mexico 54, G5686 and two susceptible cultivars, K132 and Kanyebwa. The resistant lines were crossed in cascading pyramiding scheme to develop triple crosses (TC). The TC F1 and each of the resistant parents were crossed with each of the two susceptible cultivars to generate four parent crosses (FPC) and single crosses (SC), respectively. All the population developed was inoculated with 61:63 P. griseola isolate under screenhouse conditions and their reaction was elucidated. 

Results: The SC exhibited resistance segregation ratios of 15:1 and 61:3 while TC best fitted for 249:7 and 247:9 ratios. This suggested that two or three genes were present in SC and four genes in the TC. The resistance present in the three sources to ALS race 61:63 is complex; with epistatic mode of inheritance. The four genes in FPC provided more effective resistance against isolate 61:63 than two or three genes in SC.  

Conclusion: The FPC lines with combined resistance were more effective than the individual sources for transferring resistance to susceptible cultivars. Future studies needs to be conducted to determine how broad and effective combined resistances in these newly developed lines have against the variability of the ALS pathogen sampled in Uganda.

Open Access Original Research Article

Genotype x Environment and Stability Analysis of Oil Content in Sesame (Sesamum indicum L.) Evaluated Across Diverse Agro-ecologies of the Awash Valleys in Ethiopia

Mohammed Abate, Firew Mekbib, Amsalu Ayana, Mandefro Nigussie

Journal of Experimental Agriculture International, Page 1-12
DOI: 10.9734/AJEA/2015/18482

Aim: To estimate the nature and magnitude of GEI interaction for oil content in sesame varieties and to identify stable and promising varieties for general and specific adaptations across the areas of the Awash valleys in Ethiopia.

Study Design: Entries were planted in a randomized complete block design (RCBD) replicated thrice in each location and year.

Place and Duration of Study: The study was conducted at Assaita, Melkassa and Werer representing the Lower, Upper and Middle Awash valleys of Ethiopia respectively, during the 2010/11 main cropping season and 2011/12 off season.

Methodology: Morphological data taken from each environment were analyzed for combined analysis of variance, Additive Main Effects and Multiplicative Interaction (AMMI), Biplot analysis, AMMI Stability Value (ASV), and regression analysis. Finally, ranking of genotypes was done based on the overall results of all stability indices.

Results: Combined analysis of variance showed highly significant (P<0.01) difference between the varieties, environments and GEI, suggesting differential response of varieties across testing environments and the need for stability analysis. Proportion of variance captured by environments was 1.43%, genotypes 91.5% and GEI 7.1% of the total variation, indicating less effect of environments on oil content as compared to the effect of genotypes. Stability analysis by AMMI and Joint-regression model were used to further shed light on the GEI of oil content. Two IPCA of AMMI were significant (P<0.01) and captured the largest portion of variation of the total GEI, which indicated that the AMMI model was the best for the data set. The Joint regression analysis indicated that the linear regression (bi) did not deviate from unity for all varieties, suggesting that performance of the cultivars could not be predicted in a linear manner.

Conclusion: The influence of environment is less prominent in the manifestation of oil content along the areas of Awash valleys. Season two is the best environment for growing the present set of genotypes for oil content. Variety Adi was identified as the most stable variety across environments for oil content. This variety can be recommended for varied environments of the Awash valleys to exploit its yield potential. The rest high yielder varieties, Serkamo, Tate and Argene can be adapted only under favorable environmental conditions

Open Access Original Research Article

Use of Vigor Tests in Cucurbit Rootstock Cultivars

Sitki Ermis, Eren Ozden, Ibrahim Demir

Journal of Experimental Agriculture International, Page 1-6
DOI: 10.9734/AJEA/2015/19553

Late and non-uniform emergence of rootstock seeds affect grafting efficiency in cucurbit species. As seeds age, (vigor decreases) they emerge later and the time to get graftable stage becomes longer. Therefore determination of emergence potential of a seed lot before sowing is crucially important.

This study was conducted to test accelerated ageing (AA), controlled deterioration (CD), cold tests (CT), electrical conductivity (EC) and mean germination (MGT) tests for the discriminating vigor of cucurbit rootstock seeds. AA (41°C, 72 h, 100% RH), CD (45°C, 24% seed m.c, 24, 48,72 h) tests were found to be successful for the ranking of 13 different cucurbit rootstock cultivar seeds, 12 of which were interspecific (Cucurbita maxima X Cucurbita moschata) hybrids. Cold test (CT), mean germination time (MGT) and electrical conductivity (EC) were found to be unsuccessful for the ranking of the lots. The most vigorous lots were Neffiac, Nun 9075 and Shintosa; while 90-44 and Zorba were the lowest vigorous cultivars according to the ageing tests.