Fibrous Root Distribution in Blood Red Sweet Orange Trees under Semi- arid Irrigated Ecosystem

Fibrous root distribution pattern of mature trees of sweet orange cultivar Blood Red budded on rough lemon with her cleoptera and troyer citrange rootstocks were studied by root excavation method. The roots excavated from four radial distances i.e.0–75,75–150, 150–225 and 225–300 cm from the tree trunk and three depths i.e.0–15, 15–30 and 30–60 cm from the ground level indicated that fibrous root dry weight density and proportion of dry weight differed significantly at various depths and radial distances. Cleoptera has more feeder roots as compared to rough lemon and troyer. Feeder root dry weight density and dry weight proportion was almost the same between 0–15 & 15–30 cm depth and at deeper horizon there was significant decrease in all the root stocks. Approximately 70% of the total feeder roots in all rootstocks were within 0–30 cm depth i.e. intensive vertical development. The highest feeder root dry weight density was recorded at 0-75cm radial distance after that there was a sharp decrease. Troyer citrange, cleoptera and rough lemon contain about 65, 61 and 50% feeder roots up to 150 cm radial distance from the trunk. Hence, feeder roots, in troyer citrange and cleoptera may be exemplified as intensive lateral development. Rough lemon bears extensive lateral development as it has substantial amount of feeder roots at 150-225cm radial distance.