International Journal of Applied Sciences and Biotechnology

227-234

Authors: Sameer Pokhrel, Swikriti Pandey, Ashish Ghimire, Savyata Kandel

Huanglongbing (HLB), also known as citrus greening, is a devastating disease of citrus that has decimated several citrus orchards throughout the world. The disease is associated with three species of unculturable and phloem-limited bacteriae, Candidatus Liberibacter asiaticus, Candidatus Liberibacter africanus and Candidatus Liberibacter americanus. The most common species of bacteria found in Nepal is Candidatus Liberibacter asiaticus which is transmitted by an insect vector, Asian citrus psyllid (Diaphorina citri). This disease has been detected in several economically important citrus production areas of Nepal, which resulted in heavy yield loss. No cure for the disease has been discovered yet and it is essential to practice proper management strategies to maintain citrus health and sustain citrus production under HLB pressure. Several disease management approaches such as pathogen-free nursery establishment, use of disease tolerant rootstock cultivars, proper irrigation and nutrient supply, removal of HLB affected trees, and control of psyllid with frequent insecticide application are widely practiced throughout the world. This review article highlights the characteristics of the citrus greening disease and its insect vector and gives insights into their management techniques. Several technologically advanced options available to minimize the HLB infection might not be feasible currently in Nepal due to economic and topographic constraints. This article also aims to bring into focus the cost-effective methods that growers in Nepal can practice to mitigate the impact of HLB disease in their citrus orchards.

242-249

Authors: Gapili Naoura, Doyam Nodjasse Amos, Djinodji Reoungal, Djenaissem Alfred

The phytoparasite, Striga spp., is a major biotic constraint to cereals production in sub-Saharan Africa. This study was carried out at station of Bébédjia of Chadian Institute of Agronomic Research for the Development in Sudanian agricultural zone of Chad, on traditional methods of controlling Striga spp. This study helped to find out several methods of controlling Striga among which the most important is the agronomic method including organic and or mineral fertilization, associated crops, crop rotation and the use of false hosts and trap crops. Some farmers cultivated resistant varieties and early maturing varieties to control pest attack and some others used shea flour and herbicide treatment to reduce the effect of Striga on the farm. Most of these methods were applied by farmers from generation to generation, without a thorough study to understand their mechanism. Thus, the listed methods will be analysed by research in station to find out scientific explanations for each applied method. Then experiments will be carried out to evaluate the effectiveness of some methods previously identified by extension rural services in farmers’ area after improvement.

256-260

Authors: Tirtha Narayan Shah, Amar Kumar Sinha, Krishna Kumar Jha, Ram Jiban Prasad

Serum vitamin D is one of the fat-soluble vitamin which has the role in maintenance of calcium and phosphorus levels and ultimately proper bone health and various physiological processes. Although many studies prevail hypovitaminosis D, we focused to find out the pattern of elevated or decreased serum vitamin D level as its deficiency and surplus have adverse effects to our health.. For this, a retrospective study was done from the records present in a hospital laboratory of Devdaha Medical College and Research Institute (DMCRI), Rupandehi, Nepal from January 2018 to December 2020 where 201 participants with 70.1% male and 29.9% female with different age groups were present. From total participants, 14.9% had deficient, 42.8% had insufficient, 35.3% had sufficient and 7% had high level of serum vitamin D. Male had 2.9% deficient and 14,9% insufficient vitamin D whereas female had 11.9% deficient, 27.8% insufficient and 7.0% surplus vitamin D. The greater prevalence of hypovitaminosis D in the females than the males could be overcome by the necessary strategies in the form of further studies and judicious supplementation vitamin D in the target population by monitoring the level of serum vitamin D.