Open Access Original Research Article

Sowing Depths and Nut Sizes Effects on Seedling Emergence and Growth of Cashew (Anacardium occidentale L.)

E. A. Adeyemi, H. Tijani-Eniola, O. S. Ibiremo

International Journal of Plant & Soil Science, Page 1-8
DOI: 10.9734/IJPSS/2017/10436

Damage on aerial cotyledons from emerging cashew (Anacardium occidentale L.) by rodents severely affects seedling establishment in the field. The objective of this study was to evaluate sowing depth of cashew as a possible means of reducing pest attack and damage to seedlings during establishment via in-situ sowing. The study was conducted under shade of Gliricidia sepium trees at the Cocoa Research Institute of Nigeria (CRIN) central nursery, using two nut sizes: jumbo ( ≥ 16 g) and medium (6 - 8 g) and five sowing depths: 5.0, 7.5, 10.0, 12.5 and 15.0 cm in 2005; 2.5, 5.0, 7.5, 10.0 and 12.5 in 2006. The treatments were arranged in a randomized complete block design (RCBD) with four replications. Data were collected on days to emergence, percentage emergence, position of cotyledons (above or below soil level), plant height, stem diameter and analyzed using ANOVA. Means were separated using least significant difference (LSD). Jumbo and medium nuts emerged at similar periods (22 and 21days respectively). Depth of sowing enhanced both the rate and total emergence. Nuts sown at 2.5 cm emerged 12 days earlier and 22% higher in emergence than those sown at 12.5 cm depth. The difference was significant (P =.05). Similarly, seedling emergence was earlier for cashew nut sown at 5.0 cm compared to those sown at 12.5 and 15.0 cm depths with significant (P = .05)  difference. Seedling emergence, growth and cotyledon concealment were in the order of 7.5 > 10.0 > 12.5 cm for the two nut sizes. The cashew seedling height and stem diameter were higher in jumbo-size nut seedlings than in medium-size with significant (P =.05) difference. Sowing at 7.5 cm soil depth gave the best performance in terms of seedling protection and growth. Jumbo nut size may be preferred by farmers to medium size in terms of initial seedling growth performance.

Open Access Original Research Article

Impact of Arsenic Stress on Leaflets and Stipes (Frond Petiole) Anatomy of Pteris vittata Linn. and P. ensiformis Burm.

F. Gbenga Akomolafe, A. Fatai Oloyede, K. C. Onwusiri

International Journal of Plant & Soil Science, Page 1-9
DOI: 10.9734/IJPSS/2017/26129

Heavy metals particularly Arsenic has been reported to alter the internal structures of plants in various ways due to higher levels of toxicity. The impacts of varying concentrations (0 mg/Kg, 30 mg/Kg, 90 mg/Kg and 150 mg/Kg) of Arsenic contamination on leaflet and stipe anatomy of Pteris vittata and P. ensiformis were investigated. The aim was to assess how Arsenic contaminations influence the anatomical properties of these plants. One fernlet was transplanted into each pot containing 5 Kg of soil treated with different concentrations of arsenic. After 12 weeks of planting, the transverse sections of the leaflets and stipes in all the treatments were made, stained and mounted for microscopic observation. The result showed slight changes in the shape and reduction in thicknesses of epidermal and mesophyll cells of P. vittata unlike P. ensiformis in which the anatomical properties changed and reduced drastically as the Arsenic concentration increases. The lethal impact was observed in the 150 mg/Kg treatment of P. ensiformis on the fourth week as the plants died. Also, the effect of Arsenic was minimal on the stipe of P. vittata unlike P. ensiformis. Therefore, this result further affirmed that Arsenic has low negative impact on the internal structures of P. vittata compared to P. ensiformis.

Open Access Original Research Article

Anatomical Relationships among Three Species of Curcubitaceae

J. K. Ebigwai, A. Aniema, A. A. Egbe

International Journal of Plant & Soil Science, Page 1-9
DOI: 10.9734/IJPSS/2017/33496

Anatomical relationship among Citrullus lanatus (Thunb.) Matsum. & Nakai, Cucumeropsis mannii Naudin and Lagenaria siceraria (Molina) Standl planted in controlled conditions in the Botanical garden of the University of Calabar were determined. Standards anatomical (transverse) sections of the leaves were prepared and photo micro graphed. Generalized transverse sections of the leaf, stomata and trichome were studied. The result showed a single layer of epidermal cells, a thick cuticle on both leaf surfaces, presence of hairs and the occurrence of collenchymatous tissues along the median line of the upper surface of each leaf midrib. The palisade parenchyma consists of 2 to 3 layers of elongated, cylindrical cells which are closely packed together in all the species while the spongy parenchyma are loosely arrange with numerous intercellular spaces and are irregular in shape in all species. The vascular bundles in all the species are bicollateral but are differentially arranged depending on species. Anatomy of the leaf section reveals the presence of anomocytic stomata in all three species. The stoma was observed as completely surrounded by four to six variable shapes and sizes of subsidiary cells. The cells surrounding the stoma are quite alike to the remaining epidermal cells except among the subsidiary cells surrounding the stoma. The subsidiary cells are four (4) in L. siceraria, five (5) in C. mannii and variable (4-6) in C. lanatus. The trichome of all three species is multicellular and unbranched (uniseriate). However the shape is conical in L. siceraria and C. mannii but clavate in C.lanatus. The number of cells in the trichome varies from 2-3 in C. lanatus and 3-4 in L. siceraria and C. C. mannii. While there are ridges on the trichome of L. siceraria the terminal cell in all three species tapers. When these data were converted to numerical taxonomy using Euclidean distance, L. siceraria was observed as the out group with C. mannii and C.lanatus exhibiting about 83.3% and 66.3% shared apomorphies. The differences proved statistically significant at 0.05 confidence limit. Thus the use of anatomical evidence disagrees on the lumping of these species into one genus.

Open Access Original Research Article

Evaluation of Seed Transmission of Rhizoctonia solani and Seed Mycoflora of Ajwain

Babu Lal Fagodia, B. L. Mali, J. P. Tetarwal, R. K. Fagodiya

International Journal of Plant & Soil Science, Page 1-5
DOI: 10.9734/IJPSS/2017/35037

In vitro study was conducted Department of Plant Pathology, Rajasthan College of Agriculture, Udaipur (Rajasthan) and evaluated the seed transmission of R. solani from the seeds of eight popular cultivars of ajwain viz., Ajmer Ajwain-1, Ajmer Ajwain-2, Ajmer Ajwain-93, Pratap Ajwain, Lam selection-1, Gujarat Ajwain-1, Azad Ajwain and local cultivar. It was found that maximum recovery of the pathogens was from local cultivar and Ajmer Ajwain-93 exhibited lowest recovery of pathogens. It was also found in this study that there some differential results in recovery of R. solani from seeds of cv. Gujarat Ajwain-1 and cv. Azad Ajwain. Seed samples were collected and results revealed that in all seed mycoflora were detected in both blotter and agar plate test methods from almost all the seed samples and these fungi were Aspergillus niger, Aspergillus flavus, Aspergillus ochraceeous, Alternaria alternata, Rhizopus oryzae, Rhizoctonia solani, Dreschslera australiensis and Fusarium sporotrichioides.

Open Access Review Article

Prevalence of Viruses Infecting Sorghum in Nigeria-A Review

B. Muhammad, M. D. Alegbejo, B. D. Kashina, O. O. Banwo

International Journal of Plant & Soil Science, Page 1-11
DOI: 10.9734/IJPSS/2017/33722

Viruses infecting sorghum are widely distributed in Asia and Africa and are of economic importance. In recent years, apparent virus disease incidence has increased, probably due to changes in agricultural practices associated with the introduction of hybrids and new varieties that are being developed and released continuously. The first virus disease described on sorghum in the world was Sugarcane mosaic virus (SCMV). Nigeria is one of the leading sorghum producing countries in the world and most of its populace in the northern part depend on sorghum as their primary staple food and so far, seven viruses have been identified on sorghum in Nigeria: Maize mosaic virus (MMV), Maize stripe virus (MSpV), Maize streak virus (MSV), Sugarcane mosaic virus (SCMV), Guinea grass mosaic virus (GGMV), Sorghum mosaic virus (SrMV) and Maize dwarf mosaic virus (MDMV). This calls for proper molecular characterization and deployment of management strategies of the diseases the viruses incite. Future research needs are discussed.