Open Access Original Research Article

Sulphur and Zinc Fertilization Effects on Growth and Yield Response of Rice

A. M. Kalala, N. A. Amuri, J. M. R. Semoka

International Journal of Plant & Soil Science, Page 1-12
DOI: 10.9734/IJPSS/2016/25567

Information on critical concentration and optimum rates of fertilizers is very important in the correction of sulphur (S) and zinc (Zn) deficiencies. A study was carried in the screen house experiments to establish optimum rates and critical concentrations of sulphur and zinc in both soil and rice shoots using soils of Kilombero district, Tanzania. Two experiments were conducted, one with varied levels of S and the other with varied levels of Zn. The treatments were absolute control for both experiments, three levels of S namely 0, 20 and 40 mg kg-1 soil and three levels of Zn namely 0, 5 and 10 mg kg-1 soil. Rice (variety SARO-5) was grown in pots arranged in a randomized complete block design with three replications. The results indicated that soil critical concentration of S was 10.0 mg kg-1 and the S critical range in rice shoots was 0.18 to 0.25%. Established critical level of soil Zn was 1.4 mg kg-1 while the Zn shoots critical concentration was 22 mg kg-1. Grain yield was significantly increased for plants grown in eight and three out of ten soils tested due to an application of S and Zn, respectively. Rates of 20 mg S and 5 mg Zn kg-1 soil were optimum rates for soils with low S and Zn, respectively. The results indicated that 17 and 6 out of 19 studied soils of Kilombero had S and Zn concentration below the critical level, respectively. It was concluded that sulphur deficiency was widely spread and its application and management is crucial, while Zn deficiency was an emerging problem in the paddy soils of Kilombero valley.


Open Access Original Research Article

Incidence of Jelly Seed Disorder in ‘Tommy Atkins’ and ‘Van Dyke’ Mangoes as Affected by Agro-Ecological Conditions in Kenya

Joseph Njuguna, Jane Ambuko, Margaret Hutchinson, Willis Owino

International Journal of Plant & Soil Science, Page 1-9
DOI: 10.9734/IJPSS/2016/26447

Jelly seed disorder is one of the major problems in mango production in Kenya as well as other mango producing countries in the world. This problem manifests itself through breakdown of tissues around the seed of the  affected fruits resulting in unmarketable fruits. Although the exact cause of jelly seed in mango is unknown, some reports indicate that the condition could be due to imbalance related to Ca, Mg, N and K supply to the fruit. To establish the extent of this problem in Kenya, a study was conducted in 2013 in three major mango producing counties located in different agro-ecological zones namely Embu, Murang’a and Meru. Three farms with homogenous trees of “Tommy Atkins” and “Van Dyke” mangoes were randomly selected per county. Soil and mango leaf analysis were carried out to determine the nutrient status. Rainfall and temperature data were also recorded during the study period. At harvest time, 50 tree-ripe fruits of each variety were randomly sampled from 25 trees per site and sliced along the endocarp to expose the seed then visually examined and scored for the incidence of jelly seed using Galan Sauco scale. Soil analysis showed that, Meru vertisol and lithosols soils had higher Ca, Mg, K content compared to Murang’a eutric Nitisol soils and Embu ferralic arenosal soils. Similarly, mango leaves and fruits sampled from Meru county had higher Ca, Mg and K contents than those from Murang’a and Embu. Fruits (both varieties) from Embu county showed higher incidents of jelly seed that those from Murang’a and Meru county. Significantly higher jelly seed incidents were reported in ‘Van Dyke’ compared to ‘Tommy Atkins’ mangoes. It can therefore be concluded that incidences of jelly seed depend on the variety as well as  agro-ecological zone where the mangoes are produced.


Open Access Original Research Article

The Effect of Water and Vegetation Vigor on Citrus Production in Egypt Using Remotely Sensed Data and Techniques

Mohammed A. El-Shirbeny, A. M. Ali, M. H. Edriss, G. A. Baghdady, A. S. Dawood

International Journal of Plant & Soil Science, Page 1-11
DOI: 10.9734/IJPSS/2016/24420

The vigor of vegetation and water availability are major components in agricultural production which are affecting on crop yield quantity and quality. Crop water stress occurs continuously over the total growing period or during any one of the individual growth periods of the crop. This study aims at quantifying the Vegetation and water stress effect on Valencia orange yield through remotely sensed data and techniques to predict the yield. Landsat OLI satellite imageries provide Red (R) and Near-Infra-Red (NIR) measurements which used to calculate the Normalized Difference Vegetation Index (NDVI). Land Surface Temperature (LST) was calculated from the thermal spectral region (band 10) and integrated with air temperature measurements to estimate Crop Water Stress Index (CWSI). Three Valencia orange farms were studied and 27 samples were collected (9 samples/farm). Two cultivation seasons data sets were investigated (2013/2014 and 2014/2015). Many regression models were produced. NDVI and CWSI were modeled with yield through a regression model analysis. The first season multi-regression model was the best model where Rwas high as 0.852 and regression validation was very good. The predicted yield map showed the spatial distribution of Valencia orange yield in the field, which ranged from 6.9 (ton/fed) to 29.2 (ton/fed).


Open Access Original Research Article

Evaluation of Household Soil Conservation Technologies in Arid and Semi-Arid Lands (ASALs) (The Case of Kitui Central, Mulala and Wote Divisions in Kenya)

Matheaus K. Kauti, Titus Ikusya Kanui, Wambua Raphael, Mwobobia Royford Murangiri

International Journal of Plant & Soil Science, Page 1-7
DOI: 10.9734/IJPSS/2016/25992

The study aimed at establishing the status of soil conservation technologies in arid and semi-arid lands (ASALs) in Kitui Central, Mulala and Wote divisions in Kenya. The survey was carried out between July and August 2010. To allow for comparison, purposive sampling that considered diversity in terms of agro-ecological setting, population trends and infrastructural facilities was done to select the locations for the study in the three divisions. Simple random sampling was used to select 503 households from six locations in the three divisions for interview. Questionnaires, Focus Group Discussions (FGD) and field observations were used to collect qualitative data. Results indicate main soil types as sandy (31.7%), loam (50.1%) and clay (18.2%). Soil fertility maintenance was by adding organic manure (51%) and inorganic fertilizers (22.8%). Main conservation structures of soil in crop fields included terraces (53.9%), planted trees (28%) and planted nappier grass (7.8%) while main agricultural water sources were public tap, stream and pond dam water. Soil conservation was done by less than 50% of households despite the importance towards crop growth, yield and ultimately food security.


Open Access Original Research Article

Varied Responses and Tolerant Mechanisms towards Salinity Stress in Plants

Arvinder Singh

International Journal of Plant & Soil Science, Page 1-13
DOI: 10.9734/IJPSS/2016/24703

Among several abiotic stresses, which retard crop production on at least 1/5th of irrigated land worldwide, high saline conditions seems to be the most severe environmental stress. The plant can reveal the effects of salinity at any of its life cycle stage viz. germination, seedling, vegetative or maturity. However, the response can vary for different plants on a given salt concentration and consists of numerous morphological, physiological, biochemical and molecular changes which function in a well coordinated way to alleviate toxicity.

The reduction in growth and yield of crop plant may be attributed to the production of Reactive Oxygen Species (ROS), nutrient ion and osmotic imbalance, ion toxicity which is due to the accumulation of Na+ and Cl- ions under continuous exposure of plant to saline conditions. Moreover, varied biochemical phenomenon viz. change in proteins, enzymes expression level, chlorophyll and amino acids content etc. can also be observed in these crops. However, the plants may evade themselves with three different mechanisms i.e. osmotic stress tolerance, Naor Cl- exclusion, and by means of tissue tolerance to sodium and chloride ions. Under high salinity stress, products of enhanced activities of multiple genes encode osmolytes, ion channels, receptors, components of calcium signaling, and some other regulatory signaling factors or enzymes which enable the plant then to tolerate high salinity stress.

Open Access Original Research Article

Sustainable Mining Practices in Nigeria: A Case Study of Maiganga Coal Mining in Gombe State

E. D. Oruonye, M. Iliya, Y. M. Ahmed

International Journal of Plant & Soil Science, Page 1-9
DOI: 10.9734/IJPSS/2016/26441

The impact of mining activity on the environment has been well documented. Government efforts at achieving reclamation and rehabilitation of mine land and abandoned mines have been constrained by numerous challenges. Many studies have been carried out on coal mining activities in Maiganga area but little attention or none has been paid to the reclamation strategy of the coal mining company. This study appraises the sustainable practices in coal mining activities in Maiganga community of Akko Local Government Area (LGA) of Gombe state Nigeria. Data were collected through fieldwork and use of questionnaire, interview with key informants and focus group discussion. The findings of the study shows that (79%) of the approved mine land has not been mined, while 13% of the mine land is under active mining at the moment and 8% of the mine land has already been mined and is presently under reclamation and revegetation. The study findings revealed that 6,100 seedlings have been successfully planted on the reclaimed land. Mangifera indica constitute the highest (20%), Azadirachta indica and Tectona grandis had 16%, Anacardium occidentale 15%, Eucalyptus camaldulensis 13%, Acacia senegal 12% and Jatropher curcas 8%. The study shows that about 50,000 m2 has been reclaimed and planted with these economic trees, while another 40,000 m2 of the area has been reclaimed and will be planted with trees any moment. The present revegetation exercise of the Maiganga coal mine demonstrated that reclamation of mined pits and rehabilitation of the ecosystem is not an operation which should be considered only at, or just before mine closure but integrated into the mine operation through all phases, from exploration to construction, operation, and mine closure. This study recommends the need to sustain the present revegetation effort throughout the life cycle of coal mining activity in the area. The study also recommends the replication of this exercise in other mining areas within the country and future study on the effectiveness of the present revegetation exercise on the mined land.