Open Access Original Research Article

Mycelia Growth and Sporulation of Phytophthora colocasiae Isolates under Selected Conditions

G. A. Mbong, C. N. Fokunang, E. B. Manju, A. P. Njukeng, E. A. Tembe -Fokunang, Rachid Hanna

Journal of Experimental Agriculture International, Page 193-201
DOI: 10.9734/AJEA/2015/14814

This work was carried out at the International Institute of Tropical Agriculture (IITA), Yaoundé Nkol bisson. Ten improved and four local cultivars of taro were used to carry out a pathogenicity test of Phytophthora colocasiae isolates from which one virulent isolate from both improved cultivar BL/SM123, and BL/SM120, were selected and subsequently used in determining the effect of media, temperature, pH, and light on growth parameters- mycelia growth and spores density. There was a significant difference (P ≤ 0.05) on the growth media for the optimal fungal growth parameters. The most appropriate media for mycelia growth and spores production were V6 and V8 juice agar. The optimum temperature for mycelia growth and spore density was 24°C and also optimum pH value for spores production was 6. The selection of the best growth medium was important to screen the fungal pathogen for virulence and potential field pathogenicity testing.
Incubation in both light and dark was best for mycelia growth and sporulation.

Open Access Original Research Article

Chemical Attributes and Carbon Stratification Rates at Intercropping Corn and Palisade Grasses in No Tillage Systems

Valdinei Tadeu Paulino, João Batista de Andrade, Erika Maria Celegato Teixeira, Keila Maria Roncato Duarte, Márcia Atauri Cardelli de Lucena

Journal of Experimental Agriculture International, Page 202-215
DOI: 10.9734/AJEA/2015/17306

In integrated crop-livestock systems (ICLS), grain crop and pasture development may affect the soil organic carbon stocks and chemical soil fertility and help to renew degraded pastures, increasing land use efficiency and endeavor income. Our objectives were to evaluate changes in the soil chemical properties, carbon stock in soil and carbon stratification rates of a typical Acrudox soil, with or without ICLS, liming and fertilization. The systems studied integrated with maize were: (i) Urochloa brizantha cv. Marandu (ICLS-Ub-Mar), (ii) U. brizantha cv. Piatã (ICLS-Ub-Pia) and (iii) U. ruziziensis ICLS-Ur) and (iv) U. brizantha cv. Marandu (untreated control-UC) single without maize intercropped. Experiment was performed at the Institute of Animal Science in the municipality of Nova Odessa, São Paulo State (Brazil) using a randomized blocks experimental design. ICLS increased the C stocks and CSR that are good quality indicators of the sustainability of an agricultural system. Higher values of CSR 1.7 were found in the integrated crop-livestock systems with maize and ICLS-Ur. On the other hand, without integrated-crop-livestock and no liming, no fertilization pasture of Marandu palisade grass showed the lowest and above critical CSR=0.7. It is interesting to highlight that the liming and fertilization in crops can influence the soil chemical properties and improve the soil fertility (reduce high acidity, aluminium saturation, increase exchangeable bases and C stocks) and it promotes the higher forage accumulation and maize grains or silage.

Open Access Original Research Article

Evaluation of Guinea White Yam (Dioscorea rotundata Poir.) for Yield and Yield Components in Nigeria

E. E. Bassey, U. S. Akpan

Journal of Experimental Agriculture International, Page 216-223
DOI: 10.9734/AJEA/2015/16496

A study was conducted at the Experimental Farm of the Cross River Basin Development Authority, Oku-Iboku, Itu in Akwa Ibom State in 2012 and 2013 cropping seasons. The aim was to evaluate seven genotypes of guinea white yam (Dioscorea rotundata Poir.) accessions at the last stage of uniform yield trial (UYT) for yield and yield components. The plant characters studied were vine length, number of branches, number of leaves, length of tubers, circumference of tubers, number of tubers per plant, fresh weight of tubers and tubers yield (t/ha). The result indentified UYT 89/02602 with highest performance in six characters: number of branches, number of leaves, length of tubers, circumference of tubers, fresh weight of tubers and tuber yield (t/ha), followed by the local cultivar, Akpedu as check. Similarly, UYT 89/02677 gave superior performance for vine length and number of tubers per plant. The three genotypes could be selected for and incorporated into breeding programmes for development of hybrid varieties for Itu, Akwa Ibom State, Nigeria. Also, UYT 89/02602 and UYT 89/02677 are suitable candidates for advancement to pre-release trial and eventual varietal release.

Open Access Original Research Article

The Effect of the Foliar Application of Potassium, Calcium, Boron and Humic Acid on Vegetative Growth, Fruit Set, Leaf Mineral, Yield and Fruit Quality of 'Anna' Apple Trees

Walid Fediala Abd El- Gleel Mosa, Nagwa A. Abd EL-Megeed, Lidia Sas Paszt

Journal of Experimental Agriculture International, Page 224-234
DOI: 10.9734/AJEA/2015/16716

This experiment was carried out during 2012 and 2013 seasons on seven years old "Anna" apple trees (Malus domestica L.). Trees were planted at 5Χ5 meters on sandy loam soil under drip irrigation system in a private orchard at El-Nubaria, Behera Governorate, Egypt. The experiment involved ten foliage spraying treatments as follows: control, sprayed with water, K at 2% as potassium sulphate, Ca at 0.2% as calcium chloride, B at 0.2% as boric acid, H.A. at 5% as humic acid, potassium sulphate+ humic acid, calcium chloride+ humic acid, boric acid+ humic acid, potassium sulphate+ calcium chloride+ boric acid and potassium sulphate+ calcium chloride+ boric acid+ humic acid. The obtained results showed that potassium sulphate+ calcium chloride+ boric acid+ humic acid combination was the best treatment. This combination had the highest positive effect to improve the percentages of yield, fruit set, reducing sugar and total soluble solids. Also, it increased Ca, P, K, N, B, Zn, Mn and Fe in the leaves in the two seasons, as compared to the control. Moreover, this combination improved significantly anthocyanin concentration, TSS/acid ratio, shoot diameter, shoot length, leaf area, fruit diameter, fruit length, average fruit weight and fruit firmness. It decreased the percentages of fruit drop and acidity in the two seasons as compared to the control and the other treatments.

Open Access Original Research Article

Biodiversity and Morphological Characterization of Mushrooms at the Tropical Moist Deciduous Forest Region of Bangladesh

M. I. Rumainul, F. M. Aminuzzaman, M. S. M. Chowdhury

Journal of Experimental Agriculture International, Page 235-252
DOI: 10.9734/AJEA/2015/17301

Mushroom flora is an important component of the ecosystem and their biodiversity study has been largely neglected and not documented for the tropical moist deciduous forest regions of Bangladesh. This investigation was conducted in seven different areas of tropical moist deciduous forest region of Bangladesh namely Dhaka, Gazipur, Bogra, Rajshahi, Pabna, Jaipurhat and Dinajpur. Mushroom flora associated with these forest regions were collected, photographed and preserved. A total of fifty samples were collected and identified to fourteen genera and twenty four species. The predominant genera were Ganoderma sp. Lepiota sp. Marasmius sp. and Collybia sp. The entire mushroom flora and its morphological characteristics have been described and illustrated. This is the first investigation on mushroom flora associated with tropical moist deciduous forest region of Bangladesh.

Open Access Original Research Article

Performance of Growing Grasscutters Fed a Concentrate Diet without Supplementation with Forage

G. S. I. Wogar, T. E. Ayara

Journal of Experimental Agriculture International, Page 253-260
DOI: 10.9734/AJEA/2015/17264

Aim: To determine the effect of feeding growing grasscutters a concentrate diet without forage.
Study Design: The experiment involved three treatments with three replicates per treatment in a Completely Randomized Design.
Place and Duration of Study: The study was carried out in the Research Farm of the University of Calabar, Nigeria, between November, 2013 and March, 2014.
Methodology: Eighteen 10-weeks old male grasscutters of equal weight (850 g) were allocated randomly to three treatments (T1, T2, T3), with six grasscutters per treatment and two grasscutters per replicate. The grasscutters were fed a concentrate diet containing 23.00% crude protein, 7.00% crude fibre, and 2300.00kcalME/kg with elephant grass (Pennisetum purpureum) as forage. This study involved three feeding regimes, in which all animals were fed a concentrate diet ad libitum. Varying levels of forage, including 24, 12 and nil hours access to forage, were allowed animals in treatment 1, 2, and 3 respectively. Water was supplied ad libitum. Weights of animals were taken at the beginning of the study and every week thereafter. Records of feed intake were taken daily.
Results: Findings show that forage intake (239.90 g) was significantly (P=0.05) higher in grass cutters fed concentrate with ad libitum supply of forage, while concentrate intake (49.50 g) and total feed intake (69.40 g) were significantly (P=0.05) higher in grasscutters fed concentrate with restricted supply of forage. Average daily weight gain (11.20 g) was significantly (P=0.05) higher, while the best feed conversion ratio (4.22) and cost to gain ratio (0.40) were obtained, in grasscutters fed concentrate without forage.
Conclusion: It is concluded that the performance of growing grasscutters fed a concentrate diet without forage is superior to the performance of growing grasscutters fed a concentrate diet with forage. The indication is that commercial feeds containing the right amounts of nutrients, including fibre, and offering a low cost to gain ratio, can be packaged for the convenience of grasscutter farmers.

Open Access Original Research Article

Molecular Characterization of Selected Mutant Lines of Onion (Allium cepa L.) against Purple Leaf Blotch Disease Using SSR Markers

M. Chakraborty, T. Quddus, S. Rahman, M. A. K. Azad, M. R. Hossain, A. Hoque, M. K. Saha, M. A. Haque

Journal of Experimental Agriculture International, Page 261-267
DOI: 10.9734/AJEA/2015/17504

Aims: The purple leaf blotch (PLB) disease, for which there is no released resistant variety in Bangladesh, causes loss in production of onion in every year. The mutants of a released variety, BARI Piaz-2 has shown to possess resistance against PLB which is yet to be characterized at molecular level. An easy and simple molecular detection technique of the gene responsible for this disease will be of great use in future. The present study was thus carried out to molecularly characterize four mutant lines of onion using Simple Sequence Repeat (SSR) marker to detect the presence or absence of PLB gene conferring resistance against purple blotch disease in onion.
Place and Duration of Study: The research was carried out during the period from March, 2013 to April, 2014 in the Biotechnology Laboratory of Bangladesh Institute of Nuclear Agriculture (BINA) in Mymensingh, Bangladesh.
Methodology: DNA was extracted from the vigorously growing fresh leaf samples of 25 days old seedlings of four mutant lines namely, BP2-75/2, BP2 -100/1, BP2-100/2 and BP2-100/12 of onion using CTAB method. The molecular characterization was done using two sets of SSR markers, namely MatK-1RKIM-f/MatK-3FKIM-r and rbcLa-F/rbcLa-R.
Results: All the four mutant lines showed clear band for the primer MatK-1RKIM-f/MatK-3FKIM-r which indicates the presence of PLB gene inferring resistance against purple blotch. Clear band was also observed with the marker rbcLa-F/rbcLa-R in all mutant lines except BP2-100/12 indicating absence of PLB gene in BP2 -100/12 which inferred susceptibility against purple blotch of onion. An unknown allele was also detected in this experiment which may be either linked with the PLB gene or a candidate gene which triggers the PLB gene responsible for purple blotch of onion.
Conclusion: Both the primers seemed to be effective in detecting the presence or absence of PLB gene in the studied mutant lines of onion variety BP2. However, more number of primers should be tested for effective screening of diverse germplams that will be helpful in designing any future breeding programs.