Genetic Analysis of Cucumber Collections Made in India in 1992

Abstract

Genetic variation in cucumber (Cucumis sativus L.) accessions from India was assessed by examining variation at 21 polymorphic isozyme loci. Forty-six accessions acquired by the U.S. National Plant Germplasm System (NPGS) before 1972 were compared with 146 accessions collected during a 1992 U.S.–India expedition to the states of Rajasthan, Madhya Pradesh, and Uttar Pradesh, India. Two distinct groups (Group 1 and Group 2) were identified within accessions collected in 1992 (0.025 < P < 0.01). Variation at Ak-2, Fdp-2, Gr, Mdh-2, Mpi-1, Per, Pgm, and Skdh was important in the detection of this difference. Group 1 contained 37 (27 Madhya Pradesh + 10 Uttar Pradesh) accessions and Group 2 contains 102 (84 Rajasthan + 18 Madhya Pradesh) accessions. Seven accessions (5 Madhya Pradesh + 2 Rajasthan) were not associated with either group. Isozymic variation in U.S. NPGS accessions acquired before 1972 differed significantly (P < 0.005) from those collected during 1992. When Indian accessions taken collectively (collected before 1972 and in 1992) were compared with an array of 707 C. sativus U.S. NPGS accessions examined previously, relationships differed between accessions grouped by country or subcontinent.