User:Nedavall/sandbox

Assignment 3

The genetic diversity of Digitaria exilis varies from region to region in Africa. For example, not much genetic diversity was detected among the domesticated Digitaria exilis landraces from Mali. In contrast, large levels of genetic diversity were detected among the domesticated Digitaria exilis landraces of the Upper Niger River Basin of West Africa.

Assignment 5 (500 words)

Digitaria exilis holds high nutritional value to humans. It contains methionine and cysteine, two amino acids that are important to human survival. These two amino acids, however, are lacking in wheat, rice, maize, and other cereal crops. Moving from the amino acid level to the macromolecule level, sorghum, millet, maize, wheat, rice, and Digitaria exilis vary in their respective protein, carbohydrate, and fiber content. Digitaria exilis has more protein and fiber content than rice. Additionally, Digitaria exilis has more carbohydrate content than millet, sorghum, and maize. Therefore, the nutritional benefit from Digitaria exilis outweighs the nutritional benefits from other similar cereal crops.

There are several factors that can alter this pre-existing high nutritional content. One method that distorts the nutritional composition of Digitaria exilis is the extensive processing required to bring it to an edible state. During milling, the outer layers of its grains are removed, and these layers are where the nutrients are primarily located. Therefore, with the loss of the outer layers of the grains, there is a loss in the nutrient content. As a result, the iron, zinc, and phytate concentrations present in the edible form of Digitaria exilis are reduced in abundance relative to the their respective concentrations before processing.

Additionally, the nutrient content and yield of Digitaria exilis can be affected by the soil nutrition present in the varying climatic conditions of West Africa. Through experimentation, it was seen that the nitrogen concentration in the soil has the greatest affect on the nutrition and productivity of Digitaria exilis. When nitrogen was added to the soil in limited quantities with an excess of potassium and phosphorus, productivity of Digitaria exilis increased by 22%. Such significant results were not observed, however, when either potassium or phosphorous was added to the soil with excess nitrogen and phosphorus, or with excess nitrogen and potassium, respectively. On the contrary, when nitrogen, phosphorus, and potassium were added to the soil in equal and moderate quantities, the greatest amount of yield and nutrition was seen. This overall trend is seen as a result of the low rainfall and poor soil conditions that Digitaria exilis naturally grows.

Additionally, farmers evaluated Digitaria exilis landraces on key agricultural characteristics. These included ease of processing, productivity, grain size, and facility of harvesting among many others. Based on the evaluations given by these farmers, it can be seen that the agronomic traits of Digitaria exilis would be having a big and long stem, having a long panicle with lots of grains, and having a large grain size.

From an evolutionary biology standpoint, information about the nutritional content of Digitaria exilis, factors that modify its nutritional content, and its agronomically important traits can be of importance under artificial selection of Digitaria exilis. The Digitaria exilis landraces that exhibit the greatest amount of nutrition and display the agriculturally important qualities can be further cultivated under improvement. As a result, Digitaria exilis can serve as a perennial crop to provide the human species with food security in the future.

Assignment 7: Revised Wikipedia Assignment 12/5/15

Digitaria exilis holds high nutritional value to humans. It contains methionine and cysteine, two amino acids that are important to human survival. These two amino acids, however, are lacking in wheat, rice, maize, and other cereal crops. Moving from the amino acid level to the macromolecule level, D. exilis, compared to other cereal crops, has greater protein, carbohydrate, and fiber content. Digitaria exilis has more protein and fiber content than rice. Additionally, D. exilis has more carbohydrate content than millet, sorghum, and maize. Therefore, the nutritional benefit from D. exilis outweighs the nutritional benefits from other similar cereal crops.

There are several factors that can alter this pre-existing high nutritional content. One method that distorts the nutritional composition of D. exilis is the extensive processing required to bring it to an edible state. During milling, the outer layers of its grains are removed, and these layers are where the nutrients are primarily located. Therefore, with the loss of the outer layers of the grains, there is a loss in the nutrient content. As a result, the iron, zinc, and phytate concentrations present in the edible form of D. exilis are reduced in abundance relative to the their respective concentrations before processing.

Additionally, the nutrient content and yield of D. exilis can be affected by the soil nutrition present in the varying climatic conditions of West Africa, which is where D. exilis primarily grows. Through experimentation, it was seen that the nitrogen concentration in the soil has the greatest affect on the nutrition and productivity of D. exilis. When nitrogen was added to the soil in limited quantities with an excess of potassium and phosphorus, productivity of D. exilis increased by 22%. Such significant results were not observed, however, when either potassium or phosphorous was added to the soil with excess nitrogen and phosphorus, or with excess nitrogen and potassium, respectively. On the contrary, when nitrogen, phosphorus, and potassium were added to the soil in equal and moderate quantities, the greatest amount of yield and nutrition was seen. This overall trend is seen as a result of the low rainfall and poor soil conditions that D. exilis naturally grows in.

Additionally, farmers evaluated D. exilis landraces on key agricultural characteristics. These included ease of processing, productivity, grain size, and facility of harvesting among many others. Based on the evaluations given by these farmers, it can be seen that the agronomic traits (traits that allow for a greater ease of growing to farmers) of D. exilis would be having a big and long stem, having a long panicle with lots of grains, and having a large grain size. These traits allow for easier growing and harvesting by farmers.

From an evolutionary biology standpoint, information about the nutritional content of D. exilis, factors that modify its nutritional content, and its agronomically important traits can be of importance under artificial selection of D. exilis. The Digitaria exilis landraces that exhibit the greatest amount of nutrition and display the agriculturally important qualities can be further cultivated under improvement. As a result, Digitaria exilis can serve as a perennial crop to provide the human species with food security in the future.

Digitaria exilis is where I will be posting this.