Description of the difficulties and solutions we are developing.
	Problem #1: Alfalfa chromosomes are very small, ranging from 2 - 3 µ in length in root tip cells
	The large Vicia faba chromosomes are on the left and diploid alfalfa chromosomes on the right.
	Solution: Develop and utilize a computerized image enhancement system to increase the resolution of the chromosomes. (See Bauchan and Campbell, 1994)
	The computerized image analysis system consists of a black and white video camera mounted on a research microscope which is attached to a computer. Chromosome images are projected through the microscope and the images are digitized and stored in the computer. Once the images are stored they can be color enhanced and ENLARGED.
	Problem #2: Cultivated alfalfa has 32 chromosomes which is a relatively high number of chromosomes.
	Solution: Diploid progenitor species which contain 16 chromosomes can be studied.(See Small and Bauchan, 1984)
	Problem #3: The chromosomes are morphologically very similar.
	Solution A: Utilize a computerized image analysis system to critically measure and analyze the chromosomes and develop a karyotype. (See Bauchan and Campbell, 1994.)
		Drs. Gary Bauchan and Azhar Hossain.
	Solution B: Develop a Giemsa C-banding technique which can be used to identify individual chromosomes of alfalfa. (See Bauchan and Hossain, 1997)
	C-banded chromosomes of diploid Medicago sativa ssp. falcata. Note there are only bands at the centromeres.
	C-banded chromosomes of diploid Medicago sativa ssp. caerulea. Note the multiple bands.
	C-banded chromosomes of a hybrid between ssp. falcata and ssp. caerulea. The numbered arrows are ssp. caerulea chromosomes.
	Solution C: Develop a Giemsa N-banding technique which can be used to identify individual chromosomes of alfalfa. (See Bauchan and Hossain, 1997)
	N-banded chromosomes of diploid Medicago sativa ssp. caerulea. Note the multiple bands and compare to C-banding pattern. (See Bauchan and Hossain, 1998)
	Problem #4: Where are important agronomic genes located on the chromosome?
	Solution: Develop in situ hybridization techniques to label specific genes on the chromosomes. Note: Yellow spots on the chromosomes are the location of the ß-tubulin gene which is required for cell division. (See Schaff, Koehler, Matthews, and Bauchan, 1990)
	Additional studies are being conducted to solve the mystery of alfalfa cytogenetics at the tetraploid level.
	Annual Medicago species are closely related to perennial alfalfa, however, they contain species which are diploid with mostly 16 chromosomes. However there are 5 species which have 14 chromosomes they are: M. constricta , M. murex , M. polymorpha , M. praecox , and M. rigidula . Dr. Bauchan in 1984 discovered that there are two tetraploid species M. scutellata and M. rugosa which have 30 chromosomes. (See Bauchan and Elgin, 1984).
	Medicago scutellata root tip chromosomes. Note the 4 satellited chromosomes.	Medicago scutellata pollen mother cell which has 15 bivalents at metaphase I.

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