Open Access Short Research Article

Effect of Different ‘N’ Dosages on the Bio-chemical Indices in Swietenia macrophylla (King.) & Swietenia mahogany (L.) Jacq.

R. Duraibabu, S. Manivasakan, K. Sivakumar, S. Radhakrishnan, A. Balasubramanian, M. Tilak

International Journal of Plant & Soil Science, Page 1-9
DOI: 10.9734/ijpss/2019/v27i330077

The research experiment was carried out to evaluate the effects of various nitrogen sources combination on biochemical indices in Swietenia macrophylla and Swietenia mahogany at Forest College and Research Institute, Tamil Nadu Agricultural University, Mettupalayam. The study consists of ten different types of nitrogen fertiliser combinations (Organic and inorganic sources) includes control (without any fertilisers application) to compare the treatment effect in two tree crops. Research experiment was laid out in Randomized Block Design (RBD) with three replications. Swietenia macrophylla T2 (Urea + sheep manure) combined application shows statistically significant differences in bio chemical indices (Chlorophyll a and b) after the fertiliser application during the research experiment. In Swietenia mahogany T2 (Urea alone) shows the statistically significant difference in biochemical indices (Chlorophyll a and b) during the experimental research period. In both tree, crops did not explain any statistically significant differences in Carotenoids content due to fertiliser application at the time of research experiment.

Open Access Original Research Article

Evaluation of Carbon Stock across Different Forest Physiognomy in a Tropical Rainforest Ecosystem at Obafemi Awolowo University Ile-Ife, Nigeria

Onome O. Arubasa, Anthony I. Odiwe

International Journal of Plant & Soil Science, Page 1-10
DOI: 10.9734/ijpss/2019/v27i330075

This study investigated carbon stock in above-ground biomass across different physiognomies in Obafemi Awolowo University tropical rainforest ecosystem. This was with a view of increasing the understanding of carbon cycle in tropical rainforest in Nigeria.

Two 20 m x 20 m plots were marked out in the secondary forest, Tectona grandis and Riparian vegetations. Total enumeration was carried out for the living tree, the Diameter at Breast Height (DBH) of trees ≥10 cm were measured at 1.3 m above the ground and height was also determined using a ranging pole and Haga altimeter.

Aboveground carbon stocks in standing trees ranged from 218.24 to 318.92 C t ha-1 with the highest value in Tectona grandis plantation. Trees with DBH size class 11-20 cm contributed more to Carbon stock in secondary forest and Tectona grandis plantation, while size class ≥60 cm contributed more in the riparian vegetation. Tectona grandis plantation proved to be better in mitigating carbon in our environment and this result will enhance better estimates of local and regional carbon stock which is crucial to addressing the problems of climate change.

Open Access Original Research Article

Effects of Fallowing and Nitrogen Application on Striga Infestation, Soil Fertility and Maize Performance

M. S. Bassey, M. K. A. Adeboye, M. G. M. Kolo

International Journal of Plant & Soil Science, Page 1-10
DOI: 10.9734/ijpss/2019/v27i330076

Striga possesses an ominous obstacle to the African continent that is struggling with food security as it affects the livelihood of more than 300 million people. The control of Striga has proved exceptionally difficult. Two fallows, namely natural fallow (NF) and A. histrix fallow (AF) were maintained in 2012, such that the field was divided into two parts and each part was further divided into three replicates. Each part was separated from one another by a strip of 2 m width and the fallow factor was randomly assigned to each part which constituted the main plot. In 2013, the inorganic N fertilizer levels (0, 60, 90 and 120 kg ha-1) were applied to the fallow plots and assigned to the sub-plot. These treatments were laid out in a split plot arrangement fitted to a randomized complete block design with three replicates. The two fallows significantly (P < 0.05) reduced Striga infestation similar to application of N at 60 – 120 kg N ha-1. The two fallows significantly (P< 0.05) increased SOC. Only natural fallow significantly (P<0.05) increased the STN by 36 %. Maize grain yield after natural fallow (1527 kg ha-1) was not significantly (P>0.05) different from that after A. histrix (1943 kg ha-1). Inorganic N application had highly significant (P<0.05) effect on grain yield. Lowest grain yield of 1253 kg ha-1 was obtained without inorganic N application, which was significantly different from those fertilized with inorganic N. Inorganic N fertilizer rate of 60 kg ha-1 seems to be optimum for maize. The Nitrogen Fertilizer Replacement Value of A. histrix was low, 13 kg N ha-1. The effect of both fallows on grain yield was due mainly to increased SOC content.

Open Access Original Research Article

Performance of Mungbeans (Vigna radiata (L) Willczek) in Soil Amended with Oil Palm Bunch Ash and Poultry Manure in Humid Tropical Environment of South Eastern Nigeria

Aniefiok Effiong Uko, Emmanuel Bassey Effa, Isong Abraham Isong

International Journal of Plant & Soil Science, Page 1-11
DOI: 10.9734/ijpss/2019/v27i330078

Aim: A study was conducted to evaluate supplementary effects of oil palm bunch ash (OPBA) and poultry manure (PM) on the growth and yield performance of mungbeans.

Study Design:  The study used a 3 x 3 factorial experiment laid out in randomized complete block design with three replications.

Place and Duration of Study: The experiment was carried out at the University of Calabar Teaching and Research farm, Calabar, Nigeria during the 2014 and 2015 cropping seasons respectively

Methodology: Mung bean variety NM 92 was planted in a well prepared field to evaluate its response to PM and OPBA applications. The treatments included three levels of OPBA (0, 5 and 10 t ha-1) and three levels of PM (0, 5 and 10 t ha-1. PM was cured and applied two weeks before planting while the OPBA was applied at planting.  Plant growth data including plant height, number of leaves, number of branches and leaf area were measured at 2,4, 6 weeks after planting whereas the yield data including days to fifty percent  flowering, number of pods, pod length , pod  and seed yield were recorded

Results: The highest agronomic parameters as well as yield attributing characters and yield were obtained when 10 t ha-1 OPBA or 10 t ha-1 of PM were applied. Each of the levels of applications significantly decreased the number of days to 50% flowering. The highest seed yields of 0.77 t ha-1 in 2014 and 0.82 t ha-1 in 2015 were obtained with the applications of 5 t ha-1 OPBA + 10 t ha-1 PM and 10 t ha-1 OPBA + 10 t ha-1 PM, respectively.

Conclusion: The best agronomic, yield attributing characters and yield of mungbeans were obtained when 10 t ha-1 OPBA or 10 t ha-1 of PM were applied. Also the combined application of 5 t ha-1 OPBA + 10 t ha-1 PM or 10 t ha-1 OPBA + 10 t ha-1 PM gave significantly higher increment in yield. Hence, from our study, it was found that both organic matter sources may be used to obtain higher yields in mungbeans.

Open Access Original Research Article

Response of Okra to Incorporating Humic Acid-Derived Active Molecules into NPK Fertilizer and Lime on Coastal Plain Sand in Calabar, Nigeria

S. M. Afu, E. A. Akpa

International Journal of Plant & Soil Science, Page 1-9
DOI: 10.9734/ijpss/2019/v27i330079

This study evaluated the response of okra to NPK fertilizer with humic acid and lime at the University of Calabar, Teaching and Research Farm between October 2015 and January 2016 cropping season. The experiment was laid out in a randomized complete block design (RCBD) with four replications. The experiment consisted of NPK with humic acid and liming materials as treatments. The test crop was okra. The result of initial analysis of the chemical properties of the soil before the experiment showed that the soil was acidic and was low in exchangeable bases, organic matter (1.13%), total nitrogen (0.14%) and ECEC but high in available phosphorus (26.63 mg/kg) and base saturation. After application of treatment, the result showed that 6.2 g of lime and 4.6 g of NPK with humic acid increase the soil pH from 5.6 units in the control to 5.8 in NPK with Humic Acid, 6.0 in NPK with Humic Acid and lime and 6.4 in lime. Organic carbon content, total nitrogen and available phosphorus also increase in like manner. The results for the growth parameters showed that okra height, number of leaves, and pod yield were significantly (p≤0.05) different from the control. Based on the result of this study further research is recommended in other locations to fully ascertain the effects of this treatment using a different combination.