African Journal of Crop Science

African Journal of Crop Science ISSN 2375-1231 Vol. 7 (5), pp. 001-006, May, 2019. © International Scholars Journals

Full Length Research Paper

Evaluation of slow-release nitrogen and potassium fertilizers for cotton production

Derrick M. Oosterhuis¹* and Donald D. Howard²

¹Department of Crop, Soil and Environmental Sciences, University of Arkansas, 1366 W Altheimer Drive, Fayetteville, AR 72704, U.S.A.

²Plant and Soil Sciences, West Tennessee Experiment Station, 605 Airways Blvd, Jackson, TN 38301, U.S.A.

Accepted 16 March, 2019

Abstract

Current nitrogen (N) and potassium (K) fertilization involves the use of conventional fertilizer materials with little information on the use of slow release materials. The objectives of this research were to evaluate new programmed slow -release N and K fertilizers for cotton production. Field experiments were conducted in 1997 and 1998 in Tennessee and Arkansas in the USA. The applied nutrient rates were a percentage of the total recommended rates for each state. In 1997, the applied percentages were 100, 80, and 60%; an additional 40% rate was evaluated in 1998. The recommended rate of either N or K was applied as conventional fertilizers controls. These varying rates of programmed-release materials were applied in direct contact with the seed at planting while the conventional fertilizers were broadcast before planting. Cotton yields were not reduced when the N rate was reduced to 60% recommended rate and applied as Meister programmed slow- release N. Yields were reduced when N applications were further reduced to 40% the recommended rate in 1998. Similarly, in-furrow applications of the slow-release K at 60% of the recommended rate did not affect yields for both states. Our results indicate that programmed-release; soil-applied fertilizers can potentially provide a one-time fertilizer application at planting with no detrimental effect on seedling germination, growth or yield. Furthermore, nutrient efficiency for applying the slow-release materials was increased by maintaining high yields at reduced fertilizer rates.

Key words: cotton, nitrogen, potassium, Meister programmed release fertilizer, slow-release fertilizer, lint yield.

African Journal of Crop Science ISSN 2375-1231 Vol. 7 (3), pp. 001-004, March, 2019. © International Scholars Journals

Full Length Research Paper

Studies on the chemical composition and storage parameters of sun-dried Kola nuts

Samuel Tetteh Lowor

Cocoa Research Institute of Ghana, P.O. Box 8, Akim-Tafo, Ghana. E-mail: [email protected].

Accepted 10 October, 2018

Abstract

Kola nuts (Cola nitida) were sun dried to determine their storage and suitability parameters for possible export. Moisture content of nuts could be reduced to 7 - 9% by sun-drying in wooden trays with raffia mat bases. Milled nuts stored for 12 months in sealed polybags at room temperature (25 - 27°C) did not significantly (P 0.05) absorb moisture over the period of storage. The chemical composition of most of the non-volatile components (protein, fibre, ash, non-soluble sugars, caffeine, lipids, potassium and total nitrogen) in the sun-dried nuts did not significantly differ from that of the fresh and cured nuts. There were, however, significant differences in soluble sugars and total polyphenols. Other differences observed were in the volatile profile of the nuts taken through various treatments. The implications of the result are discussed.

African Journal of Crop Science ISSN 2375-1231 Vol. 7 (1), pp. 001-004, January, 2019. © International Scholars Journals

Full Length Research Paper

Effect of sorghum cultivars on population growth and grain damages by the rice weevil, Sitophilus oryzae L. (Coleoptera: Curculionidae)

Ladang Y. D¹*, Ngamo L. T. S¹, Ngassoum M. B¹, Mapongmestsem P. M.¹ and Hance T²

¹University of Ngaoundéré, Faculty of Sciences, PO Box 454, Cameroon.

²Laboratory of Ecology and Biogeography, Biodiversity Research Centre, 4-5 Place Croix du Sud, 1348, Louvain-la-Neuve, Belgium.

Accepted 03 January 2018

Abstract

In northern Cameroon, the rice weevil, Sitophilus oryzae L. (Coleptera: Curculionidae) is a major pest of Sorghum bicolor (Poaceae) during storage. This staple crop is currently damaged by many insects and others pests during storage. To reduce the post-harvest losses due to S. oryzae, many control strategies are performed. An important step to achieve successful control is to isolate and characterize the noxious activity of rice weevil present on the sorghum variety currently stored. The present study shows that the two main ecotypes of S. bicolor, the “djiigari” ecotype is very susceptible to the 7 weevils strains isolated in the region. In a period of 100 days a single female of one of the most prolific strains produces 24 adults and more than 57% of grains are attacked. In the “safraari” ecotype, the level of attack is very low. This suggests that efforts should be made to advice the farmers to prefer “safraari” ecotype in order to avoid post harvest losses due to S. oryzae.

Key words: Sorghum bicolor, stored products, Sitophilus oryzae, Cameroon.

African Journal of Crop Science ISSN 2375-1231 Vol. 7 (1), pp. 001-003, January, 2019. © International Scholars Journals

Short Communication

Adaptation of oilseed mustard under Kenyan conditions

M. J. Mahasi, P. Mbehero and J.W. Kamundia

Kenya Agricultural Research Institute (KARI)P. O. Njoro, Kenya.

Accepted 08 November, 2018

Abstract

There is great potential for producing oilseed mustard as a cash crop and alternative crop for Kenya since its very early maturing (80 days) and highly adaptable. Oilseed mustard offers promise for semi-arid areas where Canola is not adapted. Its early maturity makes it an ideal break crop. The largest wheat and maize producing districts are experiencing excessive soil acidity, disease and pest problems due to continuous cropping. To alleviate this, a cheap and environmentally safe alternative crop has to be sought. During the 4 months fallow period after harvest, mustard can be seeded and ploughed in as green manure to increase the organic matter in the soil or the seed can be harvested and sold to the processors. The performance trials were conducted in two years ( 2002 and 2003) and comprised of 10 cultivars of oilseed mustards. These were planted at Njoro, Lanet and Naivasha in a Completely Randomized Block Design (RCBD) with 4 replicates. The seed rate was 10 kg/ha. The source of nitrogen and phosphorus was DAP mixed with the seed at 100 kg/ha during planting. Recommended agronomic practices were followed and data collected on various agronomic parameters but only the seed yield was subjected to Analysis of Variance (ANOVA). The genotypes were significantly different (P< 0.05) in Njoro and Lanet in 2002 and at all sites in 2003. However seed yields at Lanet were generally low compared to the other 2 sites. Five lines in Njoro (Kenmd 02, Kenmd 03, Kenmd 08, Kenmd 09, Kenmd10) ranged between 1273 and 1302 kg/ha. Kenmd 09 and Kenmd 10 yielded highest in Naivasha (1226 kg/ha) with the lowest yielder in Njoro (Kenmd 01) being outstanding in Naivasha (1389 kg/ha). Kenmd 02 and Kenmd 05 were superior in Njoro and Naivasha in 2003. The superior mustard lines have been recommended for commercial production.

Key words: Adaptation, break/exhaust crops biofumigation, isothiocynates, agroenviroments, glucosinolates.