North East India’s orange cucumber a storehouse of vitamin A, reveals study

By Dr Aditi Jain

New Delhi: A team of agricultural scientists has found that orange-fleshed cucumber varieties from north-eastern region of the country are four to five times richer in carotenoid content (pro-vitamin A) than white flesh varieties grown widely in other parts of the country.

Orange-fleshed cucumbers are found in the tribal areas of north-east. The fruits are consumed as cooked vegetable or as chutney. People call it `Fanghma’ and ‘Hmazil’ in Mizoram and `Thabi’ in Manipur.

The varieties caught the attention of researchers while they were characterizing indigenous germplasm of cucumber deposited at the National Bureau of Plant Genetic Resources (NBPGR). On further inspection, they found that they were collected from Manipur and Mizoram. Anticipating that orange color of the plants may correspond to high carotenoid content, they decided to study their characteristics and nutrient content in detail.

                            Orange flesh and white flesh cucumber

“A lot of fruits are available which may provide recommended daily intake of beta carotene/carotenoids. However, they may be beyond the reach of the poor in developing countries. Cucumber is available at an affordable cost throughout India. Identification and utilization of carotenoid rich landraces will definitely make a difference in our efforts in the area of nutritional security,” explained Dr Pragya Ranjan, a scientist at NBPGR and a member of the study team.

For this study, scientists grew three varieties (IC420405, IC420422, and AZMC-1) from Mizoram and one (KP-1291) from Manipur in their Delhi Campus along with Pusa Uday, a white flesh variety commonly grown in north India. The orange fleshed varieties showed similar content of total sugars and slightly higher content of ascorbic acid as the normal ones. However, the carotenoid content varied with the stage of cucumber.  At a stage when it is eaten as salad, the carotenoid content in orange fleshed varieties was 2-4 times greater than normal variety. On further maturity, however, orange cucumber may have 10-50 times more carotenoid content than the white variety.

Next, researchers evaluated the plants for acceptability of taste by asking 41 individuals to taste and score them. All the participants appreciated the unique aroma and taste of these cucumbers and accepted that it could be eaten as salad or in raita.

“The accessions with high carotenoid content may be utilized directly or as a parent in cucumber improvement programs,” said Dr. Ranjan while discussing her future plans.

The research team included Anjula Pandey, Rakesh Bhardwaj, K. K. Gangopadhyay, Pavan Kumar Malav, Chithra Devi Pandey, K. Pradheep, Ashok Kumar (ICAR-NBPGR, New Delhi); A. D. Munshi and B. S. Tomar (ICAR-Indian Agriculture Research Institute). The study results have been published in the journal Genetic Resources and Crop Evolution.

(India Science Wire)