Exogenous Application of Carbohydrate Sources Positively Regulate Growth and Carbohydrate Accumulation in Spearmint (Mentha spicata)

The experiment to study the effects of exogenous application of carbohydrates sources on growth and carbohydrate accumulation of spearmint (mentha spicata) was carried out at Institute of Biological Sciences, Gomal University, D.I. Khan, Pakistan. Spearmint was grown in Completely Randomized Design (CRD) with three biological replicates of the control and treatments. Plants were treated with different carbohydrate additives (sugar and starch) along with a control group (no treatment). The additives were sprayed on the plants on daily basis for 1-2 weeks. Plant length (cm), total carbohydrate accumulation (mg/100mg) and total chlorophyll content were measured using the standard tools. Results showed that treatments and control samples showed significant variations (P < 0.05) for Plant length, total carbohydrate accumulation and total chlorophyll content. The plants of the control group were small in length (mean length: 19.65 cm) while the plants of the sugar applied samples were larger in length (mean length: 23.95 cm). The plants of the starch applied samples were the largest among all (mean length: 26.3 cm). Similarly, the plants of the control group possessed the lowest amount of carbohydrate (0.84 mg/100g) while the sugar samples possessed a high amount of carbohydrate (1.66 mg/100g) which was statistically similar to the carbohydrate content of starch samples (1.68 mg/100g). The plants of the control group showed the highest amount of chlorophyll (13.62) while the plants of the starch sample showed less amount of chlorophyll (9.76). The sugar treated samples showed the lowest amount of chlorophyll (2.32). Based on the above results, it is concluded that the external application of carbohydrates on spearmint significantly affect the total carbohydrate content and growth rate of plants.