Answer to Question #248584 in Genetics for Johannes Steven

Question

The desert plant Welwitschia mirabilis (Figure 1) is an extraordinary plant, that can survive in the hot, desert where other plants can't survive. On the other hand, food crops have little to no drought resistance or tolerance. The majority of food crops are annuals. In nature, such plants grow only in the rainy seasons, when temperatures are appropriate for vegetative growth; in agriculture, it's called the "growing season”. The Minister of Agriculture, Water, and Forestry has hypothesized that putting Welwitschia mirabilis plant’s survival skills into maize will make it drought tolerant and expand cultivation of maize to marginal arid areas of Namibia.

Imagine, you have been engaged by the Minister of Agriculture, Water, and Forestry as a scientist to make use of the Welwitschia mirabilis surviving skills to develop a maize variety that is drought tolerant, kindly detail all the steps to the Minister on how you would intend to come up with such a maize variety.

Answer 1

The seeds are 36 x 25 mm and have a large papery wing and are dispersed by wind, in spring, when the female cone disintegrates. In their natural habitat, many seeds are lost to fungal infection and to small desert animals that feed on them. The seeds remain viable for a number of years. They germinate only if fairly heavy rain is spread over a period of several days. As these conditions rarely occur, it often happens that many plants in some colonies are the same age, as they all germinated in the same good year. The seedlings, once established, depend on the fog for survival until the next rains occur.

There are more remarkable features that make Welwitschia so difficult to categorise: Unlike any other plant, the apical growth point of the stem stops growing from an early stage. This causes the stem to grow upwards and outwards, away from the original apex (which remains dead), resulting in the characteristic obconical shape. In older specimens, continued growth results in the undulating of the stem margin.