COMPARATIVE RELATIVE GROWTH RATE OF SEEDLINGS OF MANGIFERA INDICA L. VAR. 'HADEN' AND 'MANILA': PRELIMINARY DATA

Abstract

There are not many relative growth rate studies in mango, in this study the aim is to contribute to a better knowledge of Mangifera indica seedlings growth and development during the first 12 weeks after epicotyl emergence. To obtain seedlings, mango fruits of ‘Haden’ and ‘Manila’ varieties were collected in Sinaloa, Mexico during years 2003 and 2004. Seed germination occurs in 16 days. After epicotyl emergence, seedlings were transplanted in plastic bags containing 2.5 kg of soil at 25 ± 2°C with photoperiod 12/12h. Seedlings weight was recorded before they were transplanted. For ‘Manila’ all seedlings of the same seed were transplanted together. The growth analysis takes in account: the increase of biomass per unit mass per day (relative growth rate) [RGR]. RGR is affecting by three factors: the leaf area per unit leaf dry mass or specific leaf area (SLA); the allocation of mass to leaves (light capture per unit plant mass) [LMF]; the increase in biomass per unit leaf per day (unit leaf rate) [URL]. These parameters were determined in 119 days to ‘Haden’ and 124 to ‘Manila’ seedlings.