Improving Crop Productions Under Arid And Semiarid Conditions Essay

Forty percent of the earth’s land cover is classified as either arid or semi-arid environment (Clark Davis & Kay 1983), in which, billions of people mainly from developing countries, live and work. Many of the arid zone environment is classified as to dry to grow crops (Creswell & Martin 1998). Still, crops like sorghum, millets (CONSORTIUM 2011) and cashes (Creswell & Martin 1998) are grown with reasonable success, as the plants or farmers have been able to adapt to the dry environment (Creswell & Martin 1998).

Mayan civilization underwent massive developments in agriculture and within their society. According to historian Sylvanus Griswold Morley, Maya Maize agricultural practices have remained the same as they were over three thousand years ago. (Morley 128) A uncomplicated process of felling the forest, burning dried trees and bushes, planting, and switching up the spots of the cornfields every few years. This system is known as the milpa agriculture, pulled from the Aztec word for cornfield. Agricultural tools were fire-hardened, the Maya xul, a pointed planting stick, the baat, a stone axe, chim, a fiber bag for carrying the seed corn. At first, they used sticks to punch holes into the ground, but progressively obtained more advanced farming techniques. Their main crops they grew were maize (corn), beans, squash, avocados, chili peppers, pineapples, papayas, and cocoa, which was used for

Today’s world is facing many challenges given the growing concerns and current repercussions of environmental climate change and demands of a growing global population. Not only is climate change effecting the worlds ecosystems, human health and fresh water resources, it is drastically effecting the worlds agriculture. Unpredictable weather such, as rising temperatures, colder temperatures, excessive flooding, and droughts are just a few of the increasing weather instabilities, which are challenging and threatening today’s agriculture growth and production. As such, crop yields continue to decline and present a risk to future food security. As a world, we are facing an adaptation deficit leaving us very vulnerable and thus, we must seek to

In the face of climate change Sub-Saharan Africa is confronted by two main challenges of food security and water availability for human and agricultural use. These challenges are projected to increase in the coming years compounded by extreme droughts and extreme flooding in some areas. Rain-fed agriculture is the main livelihood for a majority of small scale farmers in SSA. Their main farming systems focus on the “ major crops”(maize, wheat, rice and beans) However, strategies to cultivate these crops in the region are no longer sustainable due to reliability on finite resources, high input load and vulnerability to climate change. A key alternative strategy to adapt to a changing climate is the development and promotion of Orphan crop species

in a desert climate have some mechanism that allows them to cope with water stress. Some plants

5. We observed that corn plants and pea plants (Pisum sativum) grown under the same conditions grew differently: under conditions that were often dry, the corn managed to maintain a larger percentage of green leaf area relative to brown/dry leaf area. Investigate the photosynthetic systems used by corn vs. that used by peas. Compare and contrast these two photosynthetic systems, especially with respect to water availability and usage.

It is widely recognized that desertification is a serious peril to dryland and semi-dryland environments, which cover approximately 40% of the global land surface and populate millions of humans. The global drylands face an innumerable amount of problems that present tough and perplexing research, management and policy challenges. Desertification is the degradation of grasslands, savannas, and woodlands to a more desert-like condition, with resulting decrease in plant production and the land's ability to support livestock grazing or other human uses. (United Nations et al. 2006) The focus of this paper is to identify the causes and effects of desertification and assess how we can use plants to reduce desertification and to provide a

The anthropogenic emission of carbon dioxide and other greenhouse gasses trap heat within the atmosphere, this results in Global Warming, an increase in the planet’s temperature (Vitousek, 1994). Of the potential issues arising due to increased global temperatures, the threat to agriculture is one of the most essential (Cline, 2008). Temperature is crucial to the survivability of plant species, it has been proven to be the key environmental variable in regulation of the dormancy state and germination of seeds (Vleeshouwers, Bouwmeester and Karssen, 1995).

Drought is a form of a natural abiotic stress in plants that affects plant growth and is characterized as one of the most widespread environmental stresses occurring globally (Ekmekci, Y., & Kalefetoglu T., 2005). It occurs when there is an absence of rainfall for a particular period of time. This happens when atmospheric conditions such as climate change causes extensive loss of water in soil content that damage and injure plant structure and disruption in physiology (Jaleel, C., P. Manivannan, A. Wahid, M. Farooq, R. Somasundaram and R. Panneerselvam, 2009). Drought can be considered as water deficit and desiccation (Ekmekci, Y., & Kalefetoglu T., 2005). Water deficit occur when loss of water is moderate and the stomata of the plants’ closes resulting to a limitation of gas exchange (Jaleel, C., et.al., 2009). Desiccation occur when there is an extensive loss of water that results to a disruption in the plant’s metabolism, cell structure and eventually to the termination of enzyme catalyzed reactions (Ekmekci, Y., & Kalefetoglu T., 2005). Some effects of drought in plants are as follows; decreased in cell enlargement and growth which reduces the height of plants, decline in the water content of leaves, turgor loss, altered cholorophyll (a & b) pigment concentrations and carotenoids which reduces tissue concentrations of a plant and disturbs or disrupts biochemical processes such as photosynthesis, respiration, ion uptake, translocation and nutrient metabolism (Jaleel,

In this experiment it was found that the higher the salt concentration in a solution, the lower the mass of the Beetroot. As water travels out of the extracellular environment by Osmosis, the Cell began to dehydrate and signs of cell Lysis occurred. Though Colorimeter reading results were recorded, they did not align with the mass of the Beetroot data and were classified inaccurate. Reviewing the results there was no consistent trend in the data (eg. as the salt content increased by 1% the mass loss decreased by 0.5g). It could only be stated that as the salt concentration was increased the mass of the Beetroot decreased. This experiment is related to the Salinity issues currently occurring in Australia. It has been established that the rising levels of salt in soil affects a number of things like; Agricultural production, Water quality, Ecological health of streams, Terrestrial biodiversity, Soil erosion, Flood risk, Infrastructure and fixtures, irrigation. https://www.qld.gov.au/environment/land/soil/salinity/impacts/

These populations were selected from different regions of the country; therefore some degrees of infraspecific variations were expected. These types of variations are seen in different genus as well as families. Lukovic et al. (2009) stated that plants respond to environmental variations, particularly to water availability through morphological, anatomical and biochemical adjustments that help them cope with such variations. for example, Pereira et al.

Conventional wisdom dictates that improving agricultural productivity, either through irrigation projects or the introduction of genetically modified crops, is the key step in ending rural poverty in sub-Saharan poverty. Our research overturns this assumption. By using a global poverty map and standard soil productivity measures, we find that the regions in sub-Saharan Africa with better soil quality actually experience higher rates of poverty.

The expectations of every farmer is to have high productivity of high quality when it comes to their crops. However, due to bad weather conditions this has just been a mere dream for many small holders’ farmers. Biotechnology has developed some seedlings such as the “WEMA”that are water efficiency and can resist drought since they do not require a lot of water to grow (AATF-Africa. 2015). In addition, this kind of seedlings have been made with gene compositions that are from tough environment to make them possible to withstand and climatic conditions. The purpose of a such a move is to provide hope to the farmers from the dry regions where the normal maize seedlings are not able to give high output of products (Varshney et al. 2011).

Plant water stress is a major factor affecting crop yield. With the ever-increasing human population, there is a constant stress exerted on water resources (McGwire et al., 2000). So irrigation to avoid or relieve this stress must be done judiciously, not only to avoid environmental problems such as groundwater pollution and runoff, but also to keep the cost down on a limited and expensive resource. Soil moisture sensors are often used for precision irrigation control purposes. However, soil moisture sensors can only assess the degree of water deficit stress that is imposed to the plants, but not necessarily the level of water deficit stress that is actually experienced by the plants (Sinclair and Ludlow, 1985). An assessment of leaf water content, on the other hand, may yield more detailed insight into the plant’s actual physiological response to a certain degree of low soil moisture content, and how water deficit stress is in fact experienced by the plant. Leaf water content is a key indicator of plant health, vigor and photosynthetic efficiency (Harry, 2006). Accurate retrieval of plant water content plays a crucial role in assessing drought risk (Bauer et al., 1986), select genotypes in breeding for water stress (Munjal and Dhanda, 2005), predicting wildfire and monitoring the physiological condition of vegetation (Peñuelas and Filella, 1998) and biomass (Cho et al., 2007; Mutanga et al., 2005; Ullah et al., 2012c), while in the agriculture domain it helps in scheduling

Tropical Crops Agricultural Science and Resource Management in the Tropics and Subtropics ARTS FIELD AND VEGETABLE CROPS PTS 130 Participants Prof. Dr Marc Janssens Prof. Dr. Jürgen Pohlan Abrefa Danquah Jones Alfonso Cabrera Keshav Prasad Dahal Dilys Sekafor Kpongor Alex Pacheco Bastas Eduardo Molina Gayosso Alexander R. Mendonza Marina Piatto Said Wali Dadshani Nazli Burcu Ökten Wintersemester 2002/03 Bonn . Germany 2 Summary Author/Subject Page Table 4 1. Citrullus lanatus, Abrefa Danquah Jones 5 2.