Which of the following terms best describes a collection of many techniques currently used to genetically improve plants?

The term that best describes a collection of many techniques currently used to genetically improve plants is agricultural biotechnology. This field encompasses a wide range of technologies, including genetic engineering, tissue culture, and molecular markers, among others. Agricultural biotechnology aims to enhance crop traits such as yield, resistance to pests and diseases, and tolerance to environmental stresses, thereby improving food security and sustainability in agriculture.

While genetic engineering specifically refers to techniques that allow for the direct manipulation of an organism's DNA, agricultural biotechnology embraces a broader spectrum of methods, including both advanced techniques and traditional breeding practices enhanced by modern science. Thus, agricultural biotechnology captures the entirety of practices available for genetic improvement of plants.

Micro-propagation and conventional genetics are more focused approaches or subsets within the broader agricultural biotechnology framework. Micro-propagation, for example, is a technique for rapidly multiplying plants from a small number of initial specimens, and conventional genetics refers to breeding methods used before modern biotechnology advancements. These terms do not represent the entire range of techniques used for plant genetic improvement like agricultural biotechnology does.