The Effectiveness of Different Net-coverings on Production Yield of Chinese mustard (Brassica juncea) at Royal University of Agriculture

抄録

Cambodia, among other nations in South East Asia, is a developing country that relies on its agricultural sector. More than 70% of the population farms rice is a staple crop and vegetables as a secondary crop for domestic demand and consumption. In 2013, Cambodia produced only 40-50% of the domestic demand for vegetables and the shortage was filled by imported vegetables from neighboring countries including Vietnam and Thailand. The shortage is caused by a number of factors including that vegetables are cultivated in small quantities and farmers lack funds to support improvements in crop cultivation that are necessary to address climate change, poor irrigation systems, disease outbreaks, and particularly crop destruction by pests. For instance, in 2016 crops in some provinces of Cambodia were damaged by Spodpter spp. Other insects also cause crop destruction which prompts farmers to change chemical pesticides to control additional pests. Using chemical methods to control the variety of pests that destroy Cambodian crops is not a viable long-term solution because it affects the health of both producers and consumers, the environment, and the microorganisms that are useful for cultivating high quality crops. The net-house is an installation structure using high quality mosquito netting that tolerates weather. It is suitable for growing vegetables and other crops because it creates a barrier between pests and crops to prevent damage. Using a net-house is an effective way to reduce pesticide use in vegetable production. It is also reported that net-houses have other benefits such as preventing weeds, reducing soil moisture loss, depleting sunlight, increasing yields and providing safe food. This research study has two aims (1) to assess the effects of different shapes of net-houses on growth and yield of Chinese mustard, and (2) to study the economic efficiency of growing Chinese mustard in differently designed net-houses. Experiments were conducted in triplicate using Randomized Complete Block Design. Treatments included standard net-house, covered-ridge net-house and open field as a control. Analysis revealed that using net houses increased the yield and economic efficiency of growing Chinese mustard and that the degree of benefit was affected by the design of the net house. Based on the results, recommendations are made about the most suitable method for growing high quality, pesticide-free Chinese mustard.