Effect of Cultivar and Planting Time on Resistant Starch Accumulation in Pigeonpea Grown in Virginia

Abstract

Recent recognition of indigestible starch component named as “Resistant Starch” in the human small intestine raised our interest to execute the current study to identify the best cultivar to produce high-quality pigeonpea seed to incorporate in ongoing pigeonpea breeding program. Though pigeonpea was identified as one of the food legumes with high RS, there were no published reports for pigeonpea resistant starch accumulation as influenced by planting time. The experiment was conducted twice in replicated block design with four varieties and two planting times. The resistant and non resistant (hydrolysable) starch components of ground seed powder of four pigeonpea varieties were analyzed to identify the best planting time and best cultivar for high-resistance starch accumulation. Planting time and varieties showed significant influence on resistant starch (RS), total starch (TS), and hydrolysable starch (HS) accumulation. The pigeonpea variety W1 was significantly superior from other three varieties and has highest RS value (21.4 g/100 g) with 70 per cent RS out of its total starch (28 g/100 g). The planting time 2 (June 11) produced seed with highest values for RS (18.7 g/100 g), HS (6.5 g/100 g), and TS (25.2 g/100 g). The cultivar W1 is the better one followed by GA1 for use in further crop improvement.