Open Access Original Research Article

Effects of Nitrogen and Phosphorus Application Rates on Growth and Yield of Two Sorghum Cultivars in Semi-Arid Eastern Kenya Case Study of Machakos County

Emily Bosire, Fredrick Karanja

International Journal of Plant & Soil Science, Page 1-15
DOI: 10.9734/IJPSS/2018/46983

Declining soil fertility is a main constraint toward attaining improved crop yields across the Africa continent. The soils within the area of study are generally poor in fertility, thus the importance of using chemical fertilizer to increase crop productivity. Experimental data from two sorghum cultivars (Gadam and Seredo) grown under four levels of nitrogen (N) and three levels of phosphorus (P) in the year 2014 and 2015 long and short rainfall seasons at Katumani Research Center in Machakos County, Kenya, were used to assess the effect of nitrogen and phosphorus on phenological parameters, harvested biomass and grain yield.

Analysis of variance depicted a statistically insignificant effect of N and P on phenological parameters in majority of the experiments. The two sorghum cultivars were significantly different from each other with Gadam taking approximately twelve (12) and seven days (7) less when compared to Seredo in flowering and maturity.  Only Experiment 2 showed statistically significant effect of N and P on harvested biomass.  Seredo produced higher average biomass (27.3%) than gadam in all the four experiments. N application significantly increased biomass accumulation in seredo by 10.9 and 25.3% with application of 50 Nkgha-1, 10.9 and 6.5% at 75 Nkgha-1 over the control for Experiments 1 and 4, respectively. Statistically significant response of Seredo among the different rates of fertilizer was present in Experiment 2. Seredo grain yield in Experiments 1, 2 and 4 responded positively to application of nitrogen with yields increase of 28.8%, 13.9% and 14.9%, respectively over the control (N1P1).

The sorghum plants responded more to N inorganic fertilizer. Existence of elevated amounts of soil P in the soil restricted the efficient utilization of P inorganic fertilizer by the sorghum plants.

Open Access Original Research Article

Morphological Description and Culm Anatomy in the Identification of Kyllinga Rottb. (Cyperaceae) from Some Parts of Nigeria

Ekeke, Chimezie, Ogazie, Chinedum Alozie

International Journal of Plant & Soil Science, Page 1-15
DOI: 10.9734/ijpss/2018/v26i430049

Comparative culm anatomical and morphological descriptions of 12 taxa of Kyllinga collected from different parts of Nigeria were carried out to enhance the identification of the taxa. The number of flower-head vary from 1 – 6 while the sizes vary from the flower-head in K. erecta, K. erecta var. erecta, K. erecta var. polyphylla and K. peruviana is one, K. odorata, K. nemoralis, and K. pumila 1-4, K. erecta var. africana 4, K. tenuifolia 3-4 and K. brevifolia 1-3. K. erecta var. erecta has 2-3 bracts, K. erecta 3-4, K. erecta var. polyphylla 5-6, K. odorata 3-6, K. nemoralis 4-6, K. pumila 1-5, K. bulbosa 5 and K. peruviana 3. The leaf sheaths are partly wrapped to the culm in K. nemoralis, K. odorata, and K. pumila; completely wrapped with overlap in K. erecta var. erecta and K. peruviana and completely wrapped without overlap in other species. K. pumila, K. tenuifolia, and K. erecta var. africana rhizomes are partly erect. K. nemoralis trails on the soil surface while the remaining trail beneath the ground. The culm anatomy in transverse view is triangular (K. erecta, K. erecta var. erecta, K. erecta var. polyphylla and K. bulbosa), triangular-hexagonal (K. nemoralis, K. erecta var. africana, K. odorata and K. tenuifolia), triangular-polygonal (K. brevifolia) or oval-circular (K. pumila and K. peruviana) with aggregation of vascular bundles on the peripheral and inner portions of the culm. K. erecta has 2-layers of vascular bundles, K. peruviana 4-layers of vascular bundles while others have 3-layers of vascular bundles. The number of flower-head, sizes, bract number, and culm anatomy were observed to be diagnostic among these species.

Open Access Original Research Article

Performance of Cucurbita moschata on Soil and Soilless Media

K. Okonwu, M. I. Onyejanochie, I. G. Ugiomoh

International Journal of Plant & Soil Science, Page 1-8
DOI: 10.9734/ijpss/2018/v26i430050

Cucurbita moschata is widely grown in both tropical and temperate region due to its structural adaptability. The study was carried out to assess the performance of C. moschata on soil (humus) and soilless media (NPK 15:15:15 and NPK 20:10:15 growth media). These treatments are designated as TC, TA and TB, respectively. Standard procedures were followed in the assessment of mineral elements, nutritional composition, pigment compositions, and morphological characters (vein length, leaf area and number of leaves) of C. moschata in the three treatments. Among the treatments, C. moschata had the highest vein length, leaf area and number of leaves in TA, while TC recorded the least. Nutritional compositions of C. moschata were: moisture content (80.10%, 87.10% and 69.50%), carbohydrate (5.34%, 3.80% and 15.00%), ash content (3.61%, 1.20% and 4.10%), crude lipid (0.60%, 0.80% and 0.60%), crude protein (8.75%, 6.56% and 8.75%) and crude fiber (1.60%, 0.34% and 2.05%) for the treatments (TA, TB and TC). The mineral composition of C. moschata grown in TA, TB and TC growth media respectively were Mg (138.15 mg/kg, 43.90 mg/kg and 109.15 mg/kg), Mn (73.35 mg/kg, 0.25 mg/kg and 123.30 mg/kg), K (2,892.30 mg/kg, 3,338.80 mg/kg and 1,950.80 mg/kg), Zn (47.60 mg/kg, 10.55 mg/kg, 34.00 mg/kg), Ca (2,731.50 mg/kg, 337.95 mg/kg and 426.30 mg/kg), Na (89.65 mg/kg, 108.15 mg/kg and 66.60 mg/kg) and Fe (211.25 mg/kg, 0.00 mg/kg and 137.55 mg/kg) while copper was not detected. The pigment contents indicated the presence of chlorophyll a (0.32 mg/g, 0.39 mg/g and 0.24 mg/g), chlorophyll b (0.46 mg/g, 0.64 mg/g and 0.40 mg/g), carotenoid (0.33 mg/g, 0.42 mg/g and 0.30 mg/g), and xanthophyll (0.05 mg/g, 0.10 mg/g and 0.00 mg/g) for the three treatments, respectively. The study recommends the use of NPK 15:15:15 solution in a soilless condition and the inclusion of NPK 15:15:15 to the soil to improve the performance of Cucurbita moschata.

Open Access Original Research Article

Impacts of Restoration Projects on a Sahelian Woody Vegetation after 21 Years: The Simiri Plateaus (Niger) Case Study

Laouali Abdou, Boubacar Moussa Mamoudou, Habou Rabiou, Ali Mahamane, Josiane Seghieri

International Journal of Plant & Soil Science, Page 1-12
DOI: 10.9734/ijpss/2018/v26i430051

To face the soil and vegetation degradation in Niger, anti-erosion structures, such as scarification of the surface of the ground, half-moons, benches, trenches, stony cordons, were built in 1989 on three Simiri plateaus. Native and introduced woody species were planted and grasses were sown within the structures. This study aims at evaluating what has become the restoration of the woody vegetation cover compared to an un-restored woody cover located on a nearby similar site. Dendrometric parameters and alpha and beta diversities of the four woody stands in 36 sampled plots were analyzed and compared. The following dendrometric values were found significantly lower in the control than in the restored stands: 3.9% against 12.4-16.8% for the recovery rate, 4.3 against 6.3-10.2 cm for the largest stem diameter, 0.2 against 0.8-1.2 m²/ha for the basal area, and 1.6 against 2.0-2.5 m for the tree height. However, the number of stems per trees was found significantly greater in the un-restored stand (6.6) than in the restored ones (1.8-2.7). The values of dendrometric parameters remained low, as well as the alpha and beta diversities whatever the stand. Nevertheless, population perceptions on the restoration impacts that were collected through focus groups indicated positive impacts on downstream crop yields.

Open Access Review Article

Reflections on Efforts Geared toward Improved Soil Fertility and Crop Yields in Kenya

Arusey Chebet, Ruth Njoroge, Wilson Ng’etich

International Journal of Plant & Soil Science, Page 1-8
DOI: 10.9734/ijpss/2018/v26i430048

A successful strategy aimed at enhancing crop productivity relies on its ability to be implemented practically in the field (farmers’ field). Many research-based activities and promising soil fertility technologies are largely not adopted. This paper examines the impact of the agricultural research conducted at the University of Eldoret, agricultural institutes and the government of Kenya projects at a farm level on crop yields. Precisely, this paper narrows down to research done with an aim of exploring system approaches that address soil phosphorus and its effect on increasing crop yields in Western Kenya. Strategies like the collaboration of scientists and non scientists (transdisciplinary process) produced successful results. A qualified soil test with differentiated soil testing recommendations increases the yield by about 1.5 t dry maize ha-1. Participating in a transdisciplinary process provides an additional surplus of about 1 t dry maize ha-1 yield. Economically, this is a highly attractive result; given that soil testing costs around 20 USD, a surplus of 1 t dry maize returns approximately 330 USD. Although literature registers success stories of many research work, there is slow and limited adoption rate of the output by farmers. We          suggest the development and expansion of transdisciplinary research and creation of Farmer Research Network to seek a one-size-fits-all solution for farmers to adopt technologies with proven success.