Open Access Original Research Article

Vesicular Arbuscular Mycorrhizae and Trichoderma harzianum as Biological Control Agents against Panama Disease of ‘Cavendish’ Banana Caused by Fusarium oxysporum F. Sp. Cubense Tropical Race 4

Leslie T. Ubaub, Jermely D. Requina

Asian Research Journal of Agriculture, Page 1-11
DOI: 10.9734/ARJA/2016/28386

The study was conducted to evaluate the effect of Vesicular Arbuscular Mycorrhizae (VAM) and Trichoderma harzianum against Fusarium oxysporum f. sp. cubenseTR4 on ‘Cavendish’ banana plantlets and to determine the growth performance of ‘Cavendish’ banana plantlets applied with Vesicular Arbuscular Mycorrhizae and T. harzianum.

The experiment was laid-out in Completely Randomized Design (CRD) with seven treatments and replicated three times with five samples per replication. The treatments were as follows: T1- Negative control (w/out Foc), T2- Positive control (with FocTR4), T3- 5 g of VAM alone + Foc TR4, T4- 50 g of T.  harzianumalone + Foc TR4, T5- 3 g of VAM + 50 g of T. harzianum+ Foc TR4, T6- 5 g of VAM + 50 g of T. harzianum+ Foc TR4, T7- 7 g of VAM + 50 g of T. harzianum+ Foc TR4.

Based on the result of the study, the different rates of VAM + T. harzianum delayed the symptoms appearance and reduced incidence and severity of Panama disease. Plantlets treated with 7 g of VAM + 50 g of T. harzianumreduced Foc TR4 development in terms of disease symptom appearance, has been delayed for seven (7) days; disease incidence which had a difference of 53.33%; disease severity had 36.67% compared with the Positive check.

On the effect of the agronomic characteristics, result showed significant differences from the data on the average plant height (cm) of ‘Cavendish’ banana plantlets at 60 and 90 DAT as well as the diameter of the pseudostem as influenced by VAM and T. harzianum.

Open Access Original Research Article

Common Fungi Contamination Affecting Tissue-cultured Abaca (Musa textiles Nee) during Initial Stage of Micropropagation

Jojine S. Cobrado, Alminda M. Fernandez

Asian Research Journal of Agriculture, Page 1-7
DOI: 10.9734/ARJA/2016/28353

Philippines is the world’s largest producer of abaca fiber, accounting for about 85% share of the global production in 2013. Plant tissue culture technology is being widely used for a large scale plant multiplication. Even though it is possible to produce a large number of plants by micro popagation, the greatest problem in this technique is contamination. A wide range of microorganisms (filamentous fungi, yeast, bacteria, viruses and viroids) and micro-arthropods (mites and thrips) have been identified as contaminants in plant tissue cultures. Contaminants may be introduced with the explant, during manipulation in laboratory, by micro-arthropods vectors.

The study was conducted at the Tissue culture laboratory and Research laboratory of the University of Southeastern Philippines, Mabini Unit, Pindasan, Mabini, Compostela Valley Province, Philippines to identify and characterize the fungal contaminants of abaca in vitro cultures. The plant tissue culture used MS medium sterilized using pressure cooker at 15 psi for 20 minutes. The explants were excised and surfaced sterilized with Sodium hypochlorite (Sigma-Aldrich Chenire) for three minutes. The excised explants were aseptically transferred to the culture medium in 20 culture bottles, labeled and incubated at 24°C for three weeks at the growth room. Fungi contaminants were immediately transferred and pure cultured unto PDA (Potato Dextrose Agar) at 28°C for three to seven days. Microscopic fungi were identified using diagnostic keys. For identification purposes, slide cultures were prepared on malt extract agar and stained with lactophenol-blue.

Two species of fungi were identified as fungal contaminants of the tissue-cultured abaca in the initial stage of micropropagation. Of these genera, Chrysosporium sp. like fungus occurred most frequently (10%), followed by Aspergillus sp. (5%). These fungal species were found to cause death of the culture material by some probable sources of contaminations such as handling of plant materials, culture vessels and the laboratory.

Open Access Original Research Article

Secondary Traits and Selection Environment for Drought Tolerance at Flowering in Maize (Zea mays L.) Inbreds and Their F1 Diallel Crosses

A. M. M. Al-Naggar, M. M. M. Atta, M. A. Ahmed, A. S. M. Younis

Asian Research Journal of Agriculture, Page 1-15
DOI: 10.9734/ARJA/2016/28552

The objectives of this investigation were to identify secondary trait(s) for selection of high maize grain yield under drought stress conditions and to identify whether the best selection environment is the optimum or stressed one. Diallel crosses among diverse inbreds in tolerance to drought were evaluated in the field in two seasons under two contrasting environments; well watered (WW) and water stressed (WS) at flowering using  RCBD in 3 replications. Results across seasons revealed significant differences among inbreds and among hybrids for most studied characters. Strong favorable and significant genetic correlations (> 0.91) were detected between grain yield/plant (GYPP) or drought tolerance index and each of yield components for inbreds and hybrids and days to anthesis (DTA), plant height (PH), ear height (EH), barren stalks (BS) and leaf angle (LANG) for hybrids. The traits DTA, LANG, kernels/row (KPR), kernels/plant (KPP), 100- kernel weight (100 KW) under both WW and WS environments and anthesis silking interval (ASI) under WS had high narrow sense heritability (h2n). Thus, low DTA and LANG and high rows/ear (RPE), 100KW, KPR and KPP could be considered secondary traits to drought tolerance. Selection for low PH and high KPP was more efficient in improving grain yield than selection for yield itself with a relative efficiency (RE) of -160.6 and 240.1%, respectively. Results concluded that choosing the optimum selection environment to achieve maximum gain is affected by the genotype and the trait of interest. With respect of GYPP of hybrids, the direct selection is the best, i.e. the optimum selection environment is the target environment, while for inbreds, the indirect selection is the best, i.e. the optimum selection environment for high yield under WS is the optimum environment (WW).

Open Access Original Research Article

Effects of Nitrogen Limitation on Antioxidant Enzymes, Chlorophyll Content and Grain Yield of Rice Genotypes

T. V. Kiran, P. Vijayalakshmi, Y. V. Rao, K. N. Swamy, R. Kondamudi, B. Srikanth, I. Subhakar Rao, M. Suchandranath Babu, V. Jaldhani, D. Prema Latha, C. N. Neeraja, K. Surekha, P. R. Rao, D. Subrahmanyam, L. V. Subbarao, S. R. Voleti

Asian Research Journal of Agriculture, Page 1-10
DOI: 10.9734//ARJA/2016/28503

Nitrogen is one of the important elements for rice production. Nitrogen utilization was rapidly increased from the time of green revolution, which resulted in environmental hazards. Increasing rice yield with optimized usage of fertilizers has become important for sustainable agriculture. A field study was conducted to study the effects of nitrogen limitation on antioxidant enzymes, chlorophyll content and yield of four rice genotypes. Nitrogen limitation has increased the antioxidant activity and membrane lipid peroxidation of the studied genotypes and reduced leaf chlorophyll, yield components and nitrogen uptake. Grain yield and total dry matter were positively associated with plant nitrogen uptake under both the nitrogen levels. Among the studied genotypes, narendradhan 359 showed relatively higher antioxidant activities, leaf thickness, higher grain yield, while pooja showed low yields under due to limited N conditions with lower grain yields efficiency. Among the studied genotypes narendradhan 359 could be chosen for further yield increment under limited nitrogen conditions.   

Open Access Original Research Article

Economics of Broiler Production among Rural Women in Ahiazu Mbaise L.G.A of Imo State, Nigeria

Ume Smiles Ifeanyichukwu, Jiwuba Peter – Damian Chukwunonso, Obi Justus I., Dauda Elisha

Asian Research Journal of Agriculture, Page 1-8
DOI: 10.9734/ARJA/2016/27428

This study was carried out in Ahiazu Mbaise Local Government Area of Imo state, Nigeria. This was necessitated by the need to estimate economics of broiler production, since broiler production is widely gaining prominence in recent time in the state. 200 rural women broiler farmers were selected using purposive and multi stage random sampling techniques, from which data were collected using structured questionnaire and oral interview. Percentage response and gross margin analysis were used to address the objectives. The result showed that age bracket of 42-62 constituted the majority (39%) of the broiler farmers studied, while (15%) constituted the least with a age bracket of 63-82 years. 79% of the respondents were married while 21% were single. 61% of the farmers had no extension contact while 39% had contact. 86% of the respondents were educated, while 14% had no formal of education. 39% had greater majority of farming experience, 85% of sampled farmers were landlord, while 15% were tenants, 39% of the respondents had the highest household size, and 84% were into commercial broiler production while 16% were private. The costs and return analysis showed that the gross margin for broiler production was N212,875, the total variable cost was N712,125, the total revenue generated was N925,000 ,while the benefit cost ratio was N1:1.2. Major constraints to broiler production and their percentage contributions in the study were; poor marketing price, high cost of labour, poor access to credit and disease and pest (25%). The study recommended that extension agents should be adequately motivated to enhance their efficiency and effectiveness for high production and productivity of the broiler farm. Farmers were advised to form cooperatives which would assist them in getting government grants and loans from bank without collateral. Finally, the need for farmers to be tutored broiler feed formulation in order to reduce cost of feed in broiler production are very important.